This is just one of some 80 files about machining and metalworking and useful workshop subjects that can be read at: http://www.janellestudio.com/metal/index.html ------------------------------------------------------------------ This file is primarily concerned with drilling procedures and tips for making accurate holes in metal. Related operations may also crop up in these conversations. Before beginning this web site, I was already gathering information on subjects like "Drilling Tips" and "Boring" and "Reaming" and "Lapping". They once had separate files on my computer, and originally had their own separate files here. It has become painfully obvious that while lapping is a very useful process, you folks rarely talk about it. And when you do talk about it, you often throw some lapping info into a conversation that started as boring or reaming, etc. Consequently the messages from the separate "Lapping" and "Reaming" files have been combined into the "Lapping and Reaming" text file on this site. There is still some other lapping and/or reaming info mixed in with the messages in the "Boring" text file on this site, or in this "Drilling Tips" text file you are now reading. Consequently, you should really read the last three files to find good solutions that may involve multiple processes. The "Finish and Polish" file may also be useful for your particular need, as lapping is related to some polishing techniques. And when drilling brass, you will also find tips in the "Turning Brass" file here. Let's just clarify a few terms so that we are all on track here. These are my very simple definitions. "Drilling" most commonly is the act of using a drill bit to make a "round" hole of a specific diameter. The resulting hole is often rough, and rarely of the same diameter as the drill bit, and often not even round, and can end up quite crooked in direction from the path intended. "Boring" is the act of using a boring tool to widen an existing (drilled) hole to a larger diameter. By slowly increasing the diameter of the boring tool's cutting arc in several stages (so as not to bend the tool sideways), the resultant hole is round, and straight (even if the original drill bit had wandered), and fairly smooth. "Reaming" is the act of passing a precision reaming cutter through an existing hole; the reamer is only a small amount larger in diameter than the existing hole. The reamer brings the hole to a perfectly round shape and size appropriate to the size of the reamer. The walls of the reamed hole will be smoother than a drilled or bored hole. If the original hole was straight, the reamed hole will be too. But a reamer will follow a crooked hole if that is what you started with. "Lapping" (a hole's wall) is the act of passing a lap repeatedly through the hole until the wall is smooth and free from minor defects or tool marks. The lap, usually a metal cylinder, is the perfect matching shape for the inside of the hole and is just smaller enough in diameter to allow for a lapping compound's particles to fit between the lap and the wall. The lap itself must be softer than the hole's wall material so that particles of the lapping compound might bed into the lap, but not into the wall. Depending on the smoothness required, lapping may be done with successively finer grit lapping compounds until the desired result is achieved. Lapping, properly done, does not significantly increase the diameter of the hole. Where the hole is now a very slight "interference fit" (an object to be inserted needs force or heating-of-the-hole-part/ cooling-of-the-insert-part), lapping may change that to a precision sliding fit. Bigger hole-size changes are best done with a reamer or careful boring operation first. If you got to this file directly from my HOME PAGE, return there by using your browser's back button. BUT if you came to this file as the result of a web search engine, see many additional files on my home page Machining and Metalworking at Home http://www.janellestudio.com/metal/index.html SAFETY WARNING BEWARE: DO NOT ASSUME that any subject matter or procedure or process is safe or correct or appropriate just because it was mentioned in a news/user group or was included in these files or on this site or on any other web site or was published in a magazine or book or video. Working with metals and machinery and chemicals and electrical equipment is inherently dangerous. Wear safety devices and clothing as appropriate. Remove watches, rings, and jewellery -- and secure or remove loose clothing -- before operating any machine. Read, understand and follow the latest operating procedures and safety instructions provided by the manufacturer of your machine or tool or product. If you do not have those most recent official instructions, acquire a copy through the manufacturer before operating or using their product. Where the company no longer exists, use the appropriate news or user group to locate an official copy. Be careful -- original instructions may not meet current safety standards. Updated safety information and operating instructions may also be available through a local club, a local professional in the trade, a local business, or an appropriate government agency. In every case, use your common sense before beginning or taking the next step; and do not proceed if you have any questions or doubts about any procedure, or the safety of any procedure. Follow all laws and codes, and employ certified or licenced professionals as required by those laws or codes. Hazardous tasks beyond your competence or expertise should also be contracted to professionals. Let's be really careful out there. (c) Copyright 2003 - 2016 Machining and Metalworking at Home The form of the collected work in this text file (including editing, additions, and notes) is copyrighted and this file is not to be reproduced by any means, including electronic, without written permission except for strictly personal use. ========================================================================= Date: Wed, 10 Jan 2001 17:10:35 -0000 From: "Jack Gartner" Subject: Problem drilling into cast iron I've a problem that I hope someone can help me with and/or explain. I'm trying to drill some small (#72 drill) holes in a piece of cast iron. Drilled two holes without problem, then on the third the drill bit just wouldn't work. Replaced the bit with a new sharp one, and same problem. I took a look at the part and found that where I was trying to drill, the cast iron was very shiny as if it was a different kind of metal. The majority of the part is gray except for the corner where it is a shiny silver color and seems very hard. Can anyone tell me what's going on? Can this be annealed so I can drill it? Thanks, Jack ------- Date: Wed, 10 Jan 2001 13:49:44 -0500 From: "Rich D." Subject: Re: Problem drilling into cast iron Jack: What you have is a casting with chilled spots (white iron). These happen when the casting is allowed to cool too quickly or just plain poor quality. White iron is extremely hard, almost like carbide tools. If you can find a carbide drill in that size, you might succeed in finishing the hole. Annealing requires heating for many hours in an oven to some high temp. I am not familiar with the details. Rich D. ------- Date: Mon, 22 Jan 2001 17:22:13 -0500 From: "Paul & Charlene Wilson" Subject: Re: QC Tool Post ?? I had an honest to goodness machinist show me this trick for finding the center of a piece in the lathe, and just last night it dawned on me to use the same trick to find the top of a round piece - for example, drilling a hole in a shaft for a set screw. I just laid my 6" scale on the shaft in the vise, ran the drill down till the bit pinned the scale, and moved it back and forth until the scale was horizontal. Afterwards, I wondered why I had struggled so long with this job - I'm getting slower as I get older, I guess. On the other hand, I am getting more stuff in my bag of tricks... Paul ------- Date: Fri, 02 Mar 2001 09:59:29 -0500 From: ron ginger Subject: Screw machine drills It was mentioned here a while back that screw machine size drills are very handy. They are only about half the length of normal drills, and in Sherline size machines often make it opossible to get in over work and drill where a regular drill wont fit. They are much stiffer, so often you can start a hole without a center drill. And they save a lot of cranking up and down on the Z axis. I just got the March 2001 sale flyer from MSC, and they have 2 ads for them. On page 13 there are both fractional set, split point sets and number size set, starting at $41.70 On page 9 there are more, a different brand, with several sets and styles. You don't often see these sets on sale. ron ginger ------- Date: Tue, 06 Mar 2001 05:07:45 -0000 From: ballendox~xxyahoo.com Subject: Re: How much money to spend on a drill set? John, DON'T try to "save money" here! If you're using sherline equipment, I'd suggest as FULL a set as you can afford of "split-point" stub- length drills in HSS at least 1/16 to 1/2 ,by 64ths. Split point bits are hard to re-sharpen (without expertise, or a good *darex, shameless plug for a good tool company, but NOT their "drill doctor" line!!!* drill sharpener, but they are SOOOO nice to use; and the stub length just makes 'em better. I did buy one of the cheap 115 pc. sets, and it is being filled bit by bit(pun intended) with GOOD drill bits. I'm not saying this was/is a bad thing. The 115's ARE a quick/cheap way to have ALL the sizes AVAILABLE, even though you will replace/hand grind those you use often, out of need or frustration with the poor cutting (which is okay for a once-in-awhile" cut, but not for general metal use, IMO. Hope this helps. Ballendo P.S. It can be worthwhile to have a separate set for aluminum, and you will find that the "black bits" are designed for ferrous metals, and the "shiny bits" are for aluminum (again, talking the cheap bit sets) P.P.S. I've heard other swear by the cobalt bits, but I haven't used them (in the cheap sets, that is; Good cobalt bits are as nice as they are expensive) P.P.P.S. Recently I saw a suggestion of dipping bits used in aluminum in lye to clean. It makes sense, since Lye(sodium Hydroxide: DRANO) is used to "etch" aluminum prior to painting; but I haven't tested the idea yet. ------- Date: Thu, 08 Mar 2001 17:57:32 -0500 From: ron ginger Subject: Re: Re: How much money to spend on a drill set? jbeansx~xxpacbell.net wrote: > Thanks. Do you use one of those sharpening machines to sharpen your > bits? Any affordable suggestions? This can be a long topic. There are old-timers that claim they can do a fine job by hand. I think they are a bit optimistic, or not really fussy about the drill. I have certainly never been able to freehand a drill worth a damn. There is a drill grinding jig sold by General and was sold by Sears. This is an angle mount gadget you bolt alongside your bench grinder. It sharpens one flute at a time, and you sweep the drill through an angle to get the proper relief. These sell for about US$30 last time I looked. They work OK, but the problem is you must remove the drill and turn it over to grind the second flute. There are parts of the jig to hold it, but its hard to get exactly right, particularly on the smaller drills. A recent article in HSM showed mounting one, and the most recent article has a letter to the editor noting the first article was bad in that it removed the small angle of the mount that is what causes the relief. The Darex Company make a lot of special drill sharpeners, up to multi-thousand $$$. They sell a home shop gadget called the Drill Doctor for under $200. This tool gets a LOT of controversy on rec.crafts.metalworking. Some guys really knock it, some like it. There were a couple 'recalls' when it first came out, and a number of complaints on its plastic construction. I would say the general feeling is its just barely OK. Most of the high end machines have very fancy (expensive) collets to hold the drills, and complicated cams and beveled surfaces to cause the proper relief. There is one grinder, called the SRD Drill grinder that is a very elegant and simple machine. I lucked into a used one at NAMES one year. It has a patented chuck and sharpens on the INSIDE of a cup wheel so it gets the relief by the sweep of the wheel. A very nice gadget, but hard to find used, and about $1000 new. A friend of mine that runs a machine shop for his living, makes a very convincing argument for just throwing out dull drills and buying a new one. A few humdered $ spent on a machine to sharpen under $1 drills and spening a few minutes to do it is hard to justify. My argument is that if I screw up a dril on a Sunday afternoon I can sharpen it and keep working. (But I also like collecting neat tools and machines ;-) ron ginger ------- Date: Fri, 9 Mar 2001 08:25:04 -0800 From: "Marcus & Eva" Subject: Drill grinding Hi guys: Regarding the subject of drill grinding, here's my two cents worth. We hand ground all our drills for 15 years or more in the toolroom where I worked. The hardest drills to grind are the really small ones, (less than 0.040" dia) and the really large ones. (bigger than 3/4") I've always ground split points on all my hand-ground drills. That way the radial relief is just a flat tipped at the correct angles, rather than the complex compound motion required for true helical relief, which is what the factory grinds on. Split point drills are weaker, but they cut more freely. Since the grinding motion is so much easier, its relatively simple to grind a good drill. Dress the grinding wheel nice and flat, and put a teeny radius on the right side corner. Eyeball your primary relief and grind it on. Immediately spin the drill 180 deg. and grind the second flat. Now check them both for acceptable radial relief. The point angle and consistency of relief will be easy to control because you only made one motion to grind the second flute (you spun the drill 180 deg.) Point concentricity can be adjusted now because you have a guide to work from. Once you are happy with the shape of the primary relief, you can relieve the heels of each flute with a second flat, until you are left with a skinny land. That's it! All there is to it. For big drills, chuck them up in the lathe and dress the point with a toolpost grinder. That gives you a nice reference for grinding the lips evenly. Cheers Marcus PS: Oh yeah, and like Ballendo says: practice lots!! Budget yourself 30 sec to grind a 1/4 " drill. That way you will learn not to piss around on it, and you will actually grind better drills. ------- Date: Thu, 22 Mar 2001 12:12:15 -0000 From: ballendox~xxyahoo.com Subject: re:Re: wandering drill Hello, Coupla' thoughts... Center drills must be used such that the "follow-up" drill diameter is WITHIN the cone shape made by the center drill! Otherwise, the center drill cannot do its' job! So if you are using just a "dimple" at the tip, and following it up with a 1/4 inch bit, then yes, this is incorrect procedure... The whole point (pun intended) of using a centerr drill is to have the twist drill be guided in the cut by its' OUTER diameter, NOT its point. The short length of the center drill is to eliminate deflection while drilling this initial "locating cone". Also that it has a cutting geometry designed to "try to find" the center of a spinning workpiece. Which brings us to the second point... The center drill "should" try to move to the center of the spinning stock. Of course, if you are TOO far off, it can't. So, maybe locking the lever feed and loosening the tailstock on the ways (slightly) will give better results. You can start the cut this way (even using your "muscle" to "guide" (by deflecting the tailstock with hand pressure) the center drill to the correct center as you 'slide' the tailstock on the ways to make the cone. or you could get the center dimple close enough by these means, and then tighten the tailstock, loosen the lever and finish the cut. Hope this helps. Ballendo ------- Date: Mon, 23 Apr 2001 20:04:58 -0000 From: "Gavin Eyre" Subject: Finding a Center All, I am trying to drill a small hole in the center of the end of a piece of 3/16" rod using my mill. I've tried clamping the piece in a 3/16 collet in the mill and then lowering it down into the vice which is loose on the mill table. I next close the jaws and clamp the vice down to the table. When I release the collet the piece should be centered. Well in theory - in practice I'm a few thou off. I need to be as close as possible and would appreciate any help/sug- gestions. Unfortunately I don't own a lathe, although this may change at Wyandotte this weekend! Gavin Eyre ------- Date: Mon, 23 Apr 2001 16:17:12 -0400 From: "Carol & Jerry Jankura" Subject: RE: Finding a Center I would try clamping the tube in the vise, and then use an edge finder to find the edge of the rod at two pieces. One other thing - how certain are you that the rod is actually round? When I've measured commercial tubing, it wasn't exactly round. This could account for some of your error. A few thousanths is not all that large an error. Carol & Jerry Jankura Strongsville, Ohio So many toys, so little time ------- Date: Mon, 23 Apr 2001 16:59:43 -0400 From: John Kowalchuk Subject: Re: Finding a Center At 08:04 PM 4/23/01 -0000, Gavin Eyre wrote: >I am trying to drill a small hole in the center of the end of a piece I now have a lathe so there is a different solution than I've used in the past. Think of your mill like a vertical lathe. Centre things as well as you can and mount the dril in the vise. The drill will find the centre of the spinning workpiece better than a spinning drill and fixed workpiece. John Kowalchuk maker of mutes/horns/canoes/paddles/bikes/harps Oshawa, Ontario http://home.istar.ca/~johnk Canadians don't surf the net, we paddle it. ------- From: kdolanx~xxe... Date: Mon Jul 9, 2001 3:41 pm Subject: Re: Cheap Bronze (motor speed question) In atlas_craftsmanx~xxy..., David Jenkins wrote: > On the subject of slow speeds. I have an old Dayton Drill press, but > I feel that even at the slowest pulley configuration it turns too fast > to drill steel. Is there an electronic speed control that can be > adapted to a drill motor? Thanx Dj If you have an A/C capacitor start or capacitor run motor, probably not. FWIW, here is what I've done: Needing a new motor for an Atlas 10" I acquired, I found a 3-Phase 1HP motor and an electronic Variable Frequency converter for about $300 together from an outfit in Brooklyn NY (I think it was www.dealerselectric.com). This control takes 220V single phase and converts it to 220V 3-phase of variable frequency thus variable speed for the 3-phase motor with pretty much full torque over the full range of speed 0 to the base speed of the motor. Now you can't run two motors at the same time on this control so I put the control in a convenient place and then ran 220V power from my Dryer location to the control, then 4-wire 3-phase to behind my lathe and behind my Drill Press, with recepticles in those locations. I found a surplu 3/4HP 3-phase motor pretty cheap locally which I put on my drill press. Now when I want to use the Lathe or the Drill Press I simply unplug one and plug in the other and have variable speed for either. I havn't run across an instance where this has been inconvenient, I'm the only guy out there in the garage and I can't run both machines at the same time anyway. One of these days I'm also goung to put in some wiring to alow switching of the speed control potentiometer from one location to the other as well but so far having to take a few steps to adjust the speed hasn't been a problem. All a bit more expensive rhan I originally had planned for but it is nice to have speed control for both machines. Another option, but probably more difficult conversion-wise would be to get a surplus 90VDC motor and control and adapt it to your Drill Press. Hope this is helpful. Kirk ------- From: S1 Date: Mon Jul 9, 2001 10:03 pm Subject: Re: [atlas_craftsman] Cheap Bronze You have to replace the motor with a Variable speed DC setup to reduce the speed on your drill press. As far as I know, there is no way to make a single phase AC motor variable speed. Another option, if possible is buy/ make pulleys that would get you the desired speed range. If you put a smaller pulley on the motor, or a larger one of the shaft belt-driven by the motor you can achieve speed reduction that way also. The way you calculate speed is simple. Motor RPM x diameter of motor pulley. Divided this answer by the diameter of the pulley being driven. You will get the RPM of the motor driven shaft. Gabe ------- Date: Wed, 22 Aug 2001 22:42:34 EDT From: sleykinx~xxaol.com Subject: Re: Centering on a 4 jaw chuck In a message dated 08/22/2001, lnicex~xxattglobal.net writes: > I am having problems getting a bore centered when I use a drill in the tail stock as well. I thought it was just me. I am using a #2 taper chuck with standard length drills. Usually, I use a center drill to predrill the center of the work before I use the chuck and drill. Should I be using a shorter drill or what? Iceman < Of course it depends on what you call "centered". If it is a good quality drill bit and properly sharpened it should start in your pilot hole and track fairly true. If it really has to be DNO then drill undersize and bore to within a thou or so and ream to final size. Caution! If it has to be a really close tollerance let it cool down before you finish it. You will end up undersized and if you slip the parts together while the freshly machined part is still hot, they will stick when it cools down. ------- Date: Wed, 22 Aug 2001 22:15:13 -0500 From: jmark.vanscoterx~xxamd.com Subject: RE: Centering on a 4 jaw chuck The real solution is to drill it undersize and then bore the hole with a boring bit. Drills are hardly ever right-sized or go in straight. Mark V.S. in Austin, TX ------- Date: Wed, 22 Aug 2001 22:42:34 EDT From: sleykinx~xxaol.com Subject: Re: Centering on a 4 jaw chuck Of course it depends on what you call "centered". If it is a good quality drill bit and properly sharpened it should start in your pilot hole and track fairly true. If it really has to be DNO then drill undersize and bore to within a thou or so and ream to final size. Caution! If it has to be a really close tollerance let it cool down before you finish it. You will end up undersized and if you slip the parts together while the freshly machined part is still hot, they will stick when it cools down. ------- Date: Thu, 23 Aug 2001 00:59:49 EDT From: catboat15x~xxaol.com Subject: Re: Centering on a 4 jaw chuck > You will end up undersized and if you slip the parts together while the > freshly machined part is still hot, they will stick when it cools down. And how they will stick. I made a drill pad for my tailstock with what I thought would be a press fit between the morse center with a spigot turned on and the pad with a bored hole. They would not press with the means at hand, so put the morse with the spigot in the freezer, the pad in the oven and they started on nicely, Got called away and used that partally done drill pad for years, never could get the thing assembled further on or remove it. John Meacham High Desert of California, Palmdale, Littlerock. ------- Date: Thu, 23 Aug 2001 09:05:25 -0400 From: Richard Parker Subject: Re: Re: center drill > > Mark, I tried that and it works for larger size bores. What do you > > recommend for smaller bores? Iceman >The usual method is to drill undersize and then use a reamer. The rule of thumb for finish-reamed holes it to drill 1/32" u/s, then step up to 1/64" u/s, then finish-ream at the appropriate speed and feed. Rich Parker ------- Date: Thu, 23 Aug 2001 12:55:29 -0500 (CDT) From: dswrx~xxwebtv.net Subject: centering... This is most likely "old hat" to most of you, but here is how I establish the center on round work... for instance, I want to make a threaded clevis for the end of a valve rod. Select stock that is a bit larger than the major diameter of the clevis... Chuck it into the 3-jaw chuck... Mount a center into the tail stock... (make sure the ways are cleaned and oiled) Turn on the lathe, and while stock is rotating, push the center into the work. This will establish the exact center of the stock... Replace the center with a center drill in a tail-stock chuck. Drill a shallow hole in the stock... Use progressive sizes of drills to bring the hole to the tap size and depth needed... Mount a shaft in the tail stock that will fit into the guide hole on the rear of the tap holder (all tap holders do not have this hole)... Use this set up to guide the tap, as you tap the hole. (don't turn on the lathe!).... Now, turn the stock to the appropriate diameter and shape. Leo (was once a beginner, now just an amateur) 8-) ------- Date: Thu, 23 Aug 2001 17:21:54 -0000 From: ptolemyx~xxbellsouth.net Subject: Countersinking #2 Nut Hi- I need to countersink a #2 hex nut into a piece of aluminum. I want the countersink hole to exactly fit the hex shape of the nut (the part is too small to countersink any clearance for a hex socket driver). The part is also too delicate to punch the entire countersink in one shot. The best way I can think of is to countersink the inside diameter of the hexagon and then carefully hand punch the corners. Is there some easier or faster method? Ideally, it would also be useable in brass with #0 nuts. I'm building an armature that will be repeatedly loosened and tightened. The main issues are that a nut has to be used because the material is too soft to take the stress in a tapped hole, but the nut has to fit flush with the surface (the straightened armature joints should fit cleanly through the diameter of the armature). A hex-shaped countersink would make it easy to adjust the armature by slightly loosening the screw. Neil ------- Date: Thu, 23 Aug 2001 02:05:41 -0400 From: "Rich D." Subject: Re: Countersinking #2 Nut Neil, there is no need to create a pocket that captures 100% of the nut. Only the corners are needed. Grind a good condition Allen hex wrench to a sharp square end and tap this into the hole. Try a #11 (0.191") hole. Clean out the burrs and tap in again. RichD ------- Date: Fri, 24 Aug 2001 20:47:23 -0000 From: ptolemyx~xxbellsouth.net Subject: Re: Countersinking #2 Nut Thanks RichD, Nick & Felice -- that gave me enough to get started. The method I'm working from now is to use a 2-56 nut filed sharp. I thread this on a 2-56 screw and pass it through the hole in the part so that the head end feeds through the hole in a jeweler's anvil. This holds the nut square in my undersized countersink while I tap it in with a ball peen hammer (periodically removing the burrs). The slight reaming of the hole by the machine screw is not a problem since I need clearance in that hole anyway. Neil ------- Date: Tue, 04 Sep 2001 00:39:50 -0000 From: ballendox~xxyahoo.com Subject: Re: Newbie Question of the Day --- In sherlinex, buchnerbx~xxy... wrote: > Todays question is do I need to center punch for a center drill? Also > what size center drill do I use? Should it be smaller than the drill > or larger? Bruce Buchner The center drill is designed to be rigid enough not to deflect, so NO, you don't NEED to center punch before using it. HOWEVER... The center punch is used to locate the precise position of the hole location (often using a wiggler or the "pointy-end" of an edge- finder). So, you "may" need to use the center punch to DETERMINE WHERE to use the center drill... As a side note: If you are, as you say, a newbie; I'd suggest using a center punch on all holes until you gain some experience. I have seen more than a few parts messed up by someone who feels they can just "trust" the handwheels and count turns (no dro or cnc is assumed here). Being human will getcha, IMO. There is a comfort of seeing the center punch come into position exactly below the spindle tool as you "dial to" the correct location... And also a comfort when you have "dialed to" the "correct" location and it ISN'T... Which is when that "extra effort" of center punching the layout earns its keep... The center drill depression must be LARGER than the diameter of the drill to work as designed. The idea behind the center drill is to guide the "real" drill by its outer flutes (which are what makes the hole) rather than the drillbit geometry at the center of the drill. Obviously, to do this the "cone" hole left by the center drill must be larger than the subsequent drill bit. Having said this, the use of split-point, stubby (also called screw machine length) drill bits will often eliminate the need for center punching ALL holes. But walk before ya run, okay? Hope this helps. Ballendo ------- Date: Tue, 04 Sep 2001 01:00:53 -0000 From: ballendox~xxyahoo.com Subject: Re: Newbie Question of the Day In sherlinex~xxy..., ptolemyx~xxb... wrote: > Also along these lines, I always have trouble drilling holes > crosswise through small, round stock such as 1/8" brass. The tiny > bit of wander where the bit hits the curved stock gets multiplied as > hole progresses. -Neil Neil, Please read my previous response. A few additional points: 1) Be SURE you are EXACTLY centered over the material to be drilled. 2) Use a guide block postioned above the rod. This way , you can be sure that the hole is in the correct position BEFORE it enters your part. also, the flat top of the guide block will allow you to use the techniques of my previous post, and being flat, will reduce wander. this techinique will also allow drilling holes off-cneter through round stock. To make the guide block, simply drill (or bore; depends on accuracy needed) tha MATERIAL size through TWO similarly sized blocks (of similar or harder material, if the hole is off center). Now slot with a hacksaw or slitting saw, BENEATH the material hole. The slot allows the guide block to compress aound the material to be drilled; holding it well, and the use of two blocks makes it easier to set up in the mill. 3)You may want to look at what type of tooling you are using. Trying to drill through round stock with a standard hss twist drill bit can be trying... And you are not the first to deal with this frustration! A "standard" twist drill is NOT designed for this type of work! So learn from others. Clockmakers and other trades have designed specific tool geometries for this type of drilling (spade bit, for example) Carbide is generally stiffer than HSS. 4) Don't use a "drill" at all! "Drill" with a center cutting endmill. Before you say, "But the holes I am drilling are too small to get endmills for" be sure to check COMMERCIAL tool distributors. In other words, go beyond the standard mail order distributors, who do not carry everything. Again, you are NOT the first to experience this problem! 5) You mention the unsightly nature of a "flattened" area around the hole. Try "spotting" with an endmill, then drilling on the circular flat area produced. Carefully done, this can look very nice, indeed. Be sure your structural needs are not compromised by the sharp corners remaining with this technique. Hope this helps. Ballendo ------- Date: Tue, 04 Sep 2001 22:22:15 -0000 From: gartner1x~xxhome.com Subject: Re: Newbie Question of the Day Here's a technique that I kind of stumbled across: 1) First, I scribe the location of the hole on the material; then mount it in the vice under the mill (used as a drill press). 2) Put a small center drill in the chuck and lower the drill to just above the material (not quite touching). 3) Using a small magnifying glass or loupe, I move the X and Y axis, until the drill is centered on the scribe marks as closely as possible. 4) Lower the drill until it just touches the material and give the motor pulley a turn or two by hand, just enough to make a mark in the material. 5) Lift the drill, and check to see where the mark from the drill is, then adjust the X and Y accordingly and repeat step 4 as necessary (I've noticed that if a small enough mark is made in step 4, any repositioning will eliminate the slightly off previous mark). ------- Date: Wed, 19 Dec 2001 12:39:19 -0600 From: "R and J Sport" Subject: Re: deep hole drilling From: > Jim, I agree that more barrel wall thickness is better. My problem > is I have no way to determine how deep the pitting is without boring > it out. Any ideas on that problem, what do you think of my proposed > drill? Thanks for your time. SteveB Steve: I started making muzzleloaders in 1969 and learned form the old timers. Some of my tooling came from Bill Large and V M Starr and I got a lot of tooling from the old Green River Rifle works in Utah. Greg Roberts is a friend of mine and I have worked for him. I am a cranky old fart when it comes to muzzleloaders as I build HISTORICAL REPRODUCTIONS and don't have much use for some of the plastic junk that is foisted off on the public as a muzzleloader. That said we will start on your problem. In the old days and right up till today there are still people that can make a barrel and rifle it without fancy tools. You can drill and ream a shotgun barrel with just hand tools if you are willing to spend the time. First will the gun make a good shotgun or do you just want something to go bang. If you throw the gun to your shoulder and can look straight down the top of the barrel and everything is well centered you stand a chance. If you can't you are going to have to modify the stock to be able to hit anything. A shotgun has to look where you do or it is just a club. In addition a shotgun for black powder should have at least a 26-28 " bbl to burn black powder well. Too short a tube and you end up blowing unburned powder out the muzzle. In a shotgun you don't have a lot of pressure and some of the early barrels were pretty thin, but I like to have some good meat over the breech and will not do one with less than 1 " across the flats at the rear. I don't think there is anyone who will bore and ream a tube on the cheap as this takes time to do right. I do this regularly in restoring antique guns and in re choking, but it runs about $100 a barrel and I have all the work I can stand. (I am a Chief of Police full time and do restoration and repair part time.) As for Re cutting I will tack on a note I sent to another fellow at the end. I have made old style reamers myself and I have a full selection of reamers here in the shop. I just use a series of drills to take the barrel down to smooth, but I have a couple of big lathes to do it on. You can do this by hand but you need to go slow and just take out about 1/64th. at a time if you are doing it by hand. This means a couple or three different drill sizes at least and I like to work from breech to muzzle. Reaming can be done with a hand made square reamer and then finished with various grades of emery cloth in a home made lap. Expect that this job will take a couple of days and you can do it. IF you want to stick this kind of labor into this kind of gun. If you send me your snail mail address I will send you copies of some of my notes and books on re rifling and reaming. Jim at R and J To recut a bbl in the old days they used a method that re cut one groove or land at a time. I learned this from V M Starr in South Dakota many years ago. Basically you take a hickory rod and cut a square section on one end and put this about 1 1/2 " into the damaged or worn bore. You cast a lead or pewter section around the rod and this is your guide. Then you cut out one groove and replace it with a cutter blade made from an old file. The remaining cast grooves serve as a guide and the one cutter is shimmed and pulled through each groove in turn to re cut the grooves. You must do this with the same # of shims in each groove as you want to cut them all the same. Next you do the same thing with the lands taking off only enough to get rid of the pits. It takes about a day to do a barrel but a barrel re cut or FRESHED this way will shoot like new. Mostly you are only taking a few thou. out, just enough to renew your rifling. It works and the cost is minimal but it will not work with the modern swaged rifling, only cut rifling. The swaging button work hardens the barrel. I was told the proper name for this tool is a slick. I have diagrams of some of these tools and I have a note from Bill Large showing how to sharpen the cutters I have done this and it works. If you are careful a barrel so done will shoot as good or better than new. None of my notes or diagrams are in a format that will go in an E mail but if you are interested send me your snail mail address and I will send you some stuff. ------- Date: Sat, 29 Dec 2001 09:37:13 -0800 From: "Carol & Jerry Jankura" Subject: RE: drilling round bar stock George: Did you use a center drill to provide a starting location for the drill? From your description, I'm guessing that you simply tried to push the drill into the steel. One procedure would be: 1. Mount round stock in 3-jaw chuck, 4-jaw chuck, or collet. 2. With Right Hand cutting tool, face off the end surface. 3. Attach chuck to tailstock; mount center-drill; drill center hole 4. Demount center-drill, mount 1/8 inch drill; drill hole; or 4. Demount center-drill, mount 3/32 inch drill; drill hole; 5. Demount 3/32 inch drill; mount 1/8 inch reamer; ream hole to final size. In general, a drill will give you neither a round hole, nor a hole exactly the drill size. So, if you simply need clearance, you'd use a drill to make the final hole. If you need precision, you'd drill the hole slightly undersize and then use a reamer to enlarge it to final size. In any case, be sure to use sufficient lubricant to keep the bits and reamer cool. If you allow the tools to become too hot, the cutting edge will dull faster than it should and you'll have difficulty keeping a sharp edge afterwards. Carol & Jerry Jankura ------- Date: Sat, 29 Dec 2001 10:44:36 -0800 From: "Nicholas Carter and Felice Luftschein" Subject: Re: drilling round bar stock Excellent post Jerry! One other tip: If you don't have a combined drill/countersink or center drill yet, and are waiting for MSC to deliver one, you can make a lathe boring tool which will cut the center hole, and allow drilling to continue. Basically it is a 1 flute drill, with a 60 deg. angle. A tool like this allows you to clean up off-center holes as well. See our web pages http://www.cartertools.com/nfhome.html ------- Date: Sat, 29 Dec 2001 11:05:26 -0800 From: Dave Martindale Subject: Re: drilling round bar stock Jerry's instructions are good. However, it's probably worth pointing out that a drill simply doesn't make precision holes. You can use a center drill to start the hole, which will start you out on the center axis of the headstock, but a drill may still wander off slightly while cutting. In addition, the tailstock is never perfectly aligned with the headstock, so the hole may be slightly tapered, and the edges of a drilled hole are always somewhat rough. If you follow the drill with a reamer, you'll get an accurately round hole with smooth sides, but the reamer will follow the drilled hole and also be slightly off-center and tapered, particularly if you hold the reamer in the tailstock chuck. If you really need a hole to be accurately centered and parallel to the headstock bearings, you need to add a boring stage, using a single-point boring tool. It always cuts a hole that's concentric with the headstock bearings, and the hole will be parallel as long as the headstock is aligned with the ways. I found this out the hard way while trying to make a collet for a router, where the hole must be accurately concentric with the outside of the collet. To get the accurate hole I needed, I center drilled, then drilled about 1/16 inch undersize, then bored about 0.010" undersize, then reamed. (It took me 3 tries to figure this out - I'm new at this too). Dave ------- From: Alan Marconett KM6VV Date: Thu Jan 17, 2002 6:06 pm Subject: Re: Screw Machine Drills jeastwoodlm wrote: > I bought a set of #1-#60 from Travers, part #01-071-901 for $28.10. > They are just what right size; I too have been continually frustrated > by drills that are "too long" for the Sherline mill. > I've even cut a couple of my standard length drills down with a hack > saw, but that's a quick way to use up a blade. > --- In sherlinex~xxy..., "buchnerb" wrote: > > A recent post mentioned using screw machine drills since they are > > shorter. Does anyone know of a socurce of sets for these drill. I > > have only seen them sold individually or in multiples all of one > > size. I would really like to get a set of them with a case so I can > > keep track of them. Bruce Buchner Hi Bruce, list, I have been using the tailstock chuck from my EMCO C5 lathe as a drill chuck in the mill for many years. Used all the bits I wanted from my 1-60 numbered set. Never thought much about it. It doesn't have a drawbar. Works OK. It's now back out on the lathe (downstairs). I recently bought two of Sherline's drill chucks, the 1/4" and the smaller one. They both have nice drawbars. then I noticed that the drill bits don't go in very far! NO WAY I'm going to cut off drill bits from the (Sears) set. I do also have some packs of jobber's bits, when I remember to use them! Better idea, as they are shorter, and easier to replace! I'm still trying to get a few replacements for the drill bit set (well, it IS 35 years old). Alan KM6VV ------- From: "Craig Libuse" Date: Fri Jan 18, 2002 12:00 pm Subject: Re: [sherline] Re: Screw Machine Drills > The taper mount #0 Jacobs are another story (got to ask Craig > if I can buy a 0MT-0JT arbor seperately). Marshall We don't list the 0JT adapters in the replacement parts price list because we sell them already pressed into the 0JT 5/32" chucks; however, they can be purchased separately. The 0MT to 0JT adapter is P/N 10160 ($5.50) and the 1MT to 0JT adapter is P/N 10170 (8.75). They are both in stock. Out of curiousity, what would be your projected use for a #1 Morse to #0 Morse adapter? I assume that is a male #1 to a female #0? Craig Libuse Sherline Products Inc. ------- From: "Marshall Pharoah" Date: Fri Jan 18, 2002 10:56 pm Subject: Re: [sherline] Re: Screw Machine Drills I have several #0 tapers I made to hold center drills, deburring tools, and such. It would be nice to use them in the spindle of the mill. I could just make up another set with a #1 taper, or I could probably make up the adapter myself. I've been considering making up several more #0 tapers while the compound is set up. These I would use for mounting drills into, giving me a little more room since I have the short bed lathe. Thanks, Marshall ------- From: ron ginger Date: Fri Jan 18, 2002 10:04 pm Subject: Re: Screw Machine Drills There was a discussion here several months ago about these, and I found a sale at one of the suppliers and got both the fractional and number sets. They have become my favored drill for all machines, even the larger ones where length is not a problem. They are considerably stiffer because they are shorter, and often I can drill holes without a center drill first. Every Sherline owner should get a set of screw machine drills, but watch for a sale, don't pay the $109 for a set. They do go on sale, just not very often. ron ------- Date: Sat, 02 Feb 2002 17:34:29 -0000 From: "stevenhkb" Subject: Re: Oval Holes If its an oval hole in thin plate or sheet, clamp a piece of suitable material to the plate top and bottom so you have a face at right angles to the drill bit. Mount at a suitable angle (a trig problem I don't want to get into) and drill with round bit. The resulting hole drilled thru the plate will show as a elipse. It the plate is thick, you will have angled sides, which may or may not be a problem solvable by a small round file. What is the exact problem, is the hole a true elipse or to suit some piece of metal? Steve [HUNLEY REPLY ] BTW. To those who replied to the oval hole inquiry. The oval hole is actually an elongated hole that is needed for a gimbal to pivot back and forth a bit, a shaft that passes thru changes the angle of attachment. It's the top part of an elevation devise used to aim a BP cannon. I'll be happy to send a PIC to anyone that request one. I'm going to reengineer the device using a 'ball' due to a space problem. Thanks in advance. Hank, Street, Maryland HUNLEY31x~xxaol.com... wrote: >> I've searched the Atlas/Craftsman website and can't find what I need. I'm not sure It's working right. Anyway, I think a couple of weeks ago someone posted directions for drilling oval holes. Never in my life I thought thatI'd need this information, but here I am with a need. Does anyone remember the post and can point me in the right direction? ------- Date: Mon, 11 Mar 2002 09:14:50 -0700 From: "Ron Shaw" Subject: Drilling problem I have been attempting to drill and later internally thread the end of a 1mt-2mt adapter so that I can use it with a 3/8-16 drawbar. I cut the tang off the adapter, mounted it in a three-jaw, indicated to run true within plus/minus .001, put a steady on the end to be drilled, faced it flat, spot drilled, and started drilling with drill bits held in a drill chuck mounted on the tailstock. Drill bits are cheapo imports, but new. Started drilling with a 1/8", which made it all the way through, about 3/8", with some difficulty. As I have been creeping up on the 5/16 tap size, I have run into increasing difficulty drilling, and chewed up about 3 bits in the attempt. It is as though the adapter material has become super hard about half way through, and the drills will not touch it. Screams like a banshee, and no cut, even with a brand new bit. Cutting lubes don't seem to have any effect on it, neither does speed/feed. What's up with that? Work hardened material? Crappy drill bits? Have I forgotten something elementary in the setup? Any suggestions? Ron Shaw ------- Date: Mon, 11 Mar 2002 10:48:58 -0600 From: Guy Fuller Subject: Re: Drilling problem I would say that it is case hardened. As a last resort you could heat it to a cherry red with a torch, if you dont have access to a furnace or a forge, and set it aside to slowly air cool. That will soften the metal so it can be drilled. When you have finished machining it, to harden it again heat to a cherry and quench in cool water. This rapid cooling will harden the metal again. Hope this helps. Guy F. ------- Date: Mon, 11 Mar 2002 11:57:52 -0500 From: "Ebower" Subject: Re: Drilling problem Ron, I have tried to use sleeves as well. What you have is a "hardened thru-out" Sleeve. These are the most common sleeve that is offered. You can get "Soft" sleeves but there is only one or two suppliers. Also, your drills are cheapo style. I have been using cobalt drills to do most of my drilling. You will have problems when it comes to tapping. You have not work hardened it. You should have cut the sleeve off above the knock out slot. You would then be up high enough to tap it. How are you going to use them? The drawbar should go into the taper end that you will be using, (e.g. the # 2). Earl bower machine ------- Date: Mon, 11 Mar 2002 18:30:36 +0100 From: "jcgerb" Subject: Re: Drilling problem Not forgetting that hardening will slightly change the dimensions and/or the shape of the taper. Normally they are grinded after the thermal treatment. Jean-Claude, Switzerland www.homestead.com/turnandmill ------- Date: Mon, 11 Mar 2002 12:12:19 -0600 From: jmark.vanscoterx~xxamd.com Subject: RE: Drilling problem There have been times in the past when I ran into problems like this. For metal that was too hard (and a pocketbook that was too small), I used masonry bits to enlarge the hole. The bits have a piece of carbide at the end and I have cut through a hardened leaf spring with them. Mark V.S. in Austin, TX ------- Date: Mon, 11 Mar 2002 14:32:57 EST From: Skaw5x~xxaol.com Subject: Re: Drilling problem If it is an old mt sometimes the steel when it was heat treated for hardness, wasn't heat treated properly, I would suggest running a carbide drill at low rpms. Try using pledge (that's right furniture polish) as a lubricant. I know of tool grinders that cut out high speed taps with carbide drill & pledge as a lubricant. If you are having trouble drilling it, you are going to have trouble tapping it also. You might want to go a little bigger on the tap drill. Another good lubricant that we used to use to cut rough titanium billets was Crisco lard. The scale on a billet was really hard, but once under the scale it cut allright. Scooter ------- Date: Sun, 17 Mar 2002 20:19:30 -0000 From: "toddfoh" Subject: Re: Making a "D" hole In taigtoolsx~xxy..., Bill Brady wrote: > Help! I need to make some handwheels that will go on an existing shaft > which has a flat on it. So I need to make D shaped holes. Three possibilities: 1) Make a round hole and use a setscrew on the flat of the shaft. 2) Make a round hole and make a second D shaped piece to fit in the void. Glue everything with epoxy. 3) Make the handwheels clamp to the shaft with a second straight clamp piece that clamps across the flat of the shaft. Todd F. ------- Date: Sun, 17 Mar 2002 21:46:14 -0500 From: Stan Stocker Subject: Re: Making a "D" hole Hi Bill; A couple of things come to mind. Unless the shaft is very large, cutting the D opening is probably not going to give a really good fit. You could mill a piece of rod the same diameter as the shaft down to make a D shaped filler piece, and clamp this with a set screw. This will give a nice no shake fit and allow the handwheel to run true to the shaft. The D shaped filler piece could be secured to the handwheel bore with bearing retainer compound or epoxy alternatively, using a setscrew opposite of the filler piece on the handwheel. If you do this, you might want to drill a small hole or two through the handwheel and into the filler piece, and secure with pins retained with Loctite, or at a minimum give a little more holding area for the epoxy or bearing retainer. This would help keep things from shifting. This is probably overkill, a simple dimple to take the tip of the setscrew is probably enough to keep things in place. Another option is to make a duplicate of the shaft, wither of nicely polished aluminum or better yet delrin or nylon. Coat with release compound and fill the void in the degreased handwheel with JB Weld or a steel or titanium filled epoxy, using the duplicate shaft piece as a form. Quick and dirty option would be to use 2 setscrews in the handwheel, one bearing on the flat, and one at 90 degrees to the flat. I'd see if the quick and dirty option was acceptable for the application, if not I'd go with the filler piece in the handwheel bore in preference to the epoxy fill approach. If you go with an epoxy, don't use one of the hobby epoxies for model building, they tend to creep in shear. Great for model airplanes and boats where the weight is allowable, wrong stuff for this sort of application. Either a metal filled epoxy or JB Weld would work well. These set very hard. If you are not familiar with JB Weld, it can be filed, milled, and take threads. Useful stuff to have around. Most auto parts and hardware stores have it. Take care, Stan ------- Date: Mon, 18 Mar 2002 13:00:35 -0000 From: "toddfoh" Subject: Re: Making a "D" hole Well, there are a few answers to that question. It really depends on the application. 1) If you are making parts in volume, you can cast or mold the parts. Most knobs or handwheels with a D-hole are made this way. 2) On a sheet metal part, you could punch it. 3) If it is a through hole, you could either wire EDM the hole (leaves a small radius in the corners) or make it with a custom broach. 4) In a blind hole, you can CNC machine it with a tiny diameter end mill. You might have to hand scrape or file the corners to get them really sharp. Or you could electrode EDM it. This is where you make a graphite electrode in the shape of the hole you want and plunge it very slowly into the metal. The metal is vaporized and you are left with the D-hole you want. As a designer, if I absolutely had to have a blind D-hole to mount a handwheel to a shaft, I'd probably design an insert with the hole wire EDM'd into it. Then I'd press it (or clamp it) in a round blind hole in the handwheel. Todd F. ------- Date: Mon, 18 Mar 2002 18:45:39 EST From: tadici283x~xxcs.com Subject: Re: sensitive drilling attachment In a message dated 3/17/2002, benedictx~xxaustin.rr.com writes: > > Has anyone made a sensitive drilling attachment for the Taig. > > Sherline has one, but it appears that it will not fit the Taig. I > > have a lot of very small holes to drill and something like this looks > > good. I do not want to drill out the headstock bore to fit the > > Sherline. Any suggestions? I have built a micro feed tailstock, go to Nick Carters web site to read about it, I have mentioned this before, but what I did is mill out the center section of the standard Taig tailstock and place in Taigs crosslide in between so that you have both crank feed and ram style feed and it effectively increased the total tailstock movement to greater than 3 inches, this was needed because I could not get "gentle" enough feed for my watch making and repairing projects, my headstock is able to move to the tailstock rather than move the tailstock up to the chuck or collets this gave me room for my big hands to clear the end of the lathe bed. I have to say that getting the new tailstock aligned with the headstock was more than a pain, watch making requires super close tolerances, and even to my surprise the Taig performs at near watch maker lathe tolerances. My motor is mounted on the Taig headstock just like the mill but is mounted to the rear behind the lathe so new brackets were needed to be made, I have tested this system, there is not a problem with the motor deflecting the headstock with the motor's weight or dynamic stress, Taig builds a generous overkill machine. Chris DiCintio of Bradenton FLA ------- Date: Tue, 29 Oct 2002 14:43:52 -0800 From: Alan Marconett KM6VV Subject: Drilling angled holes Hi to the list, I'm working on the cylinder for the Stuart steam engine, and I have some angled holes to drill. The first one is on a simple angled surface, looks like about 77 degrees (near perpendicular). I will of course set up on the adjustable angle plate, but I'm wondering whether to use a center drill to start the hole, or to first use an endmill to get a flat. The second one is about 55 degrees, but it goes into a corner! Small hole in the case of the corner, about .098". The first one gets a 1/4"-32 thread. Both these holes must "break out" into other machined passages. I'm working in aluminum FIRST, until I'm satisfied my setup is OK! And to boot, I'll get parts for a second engine! Alan KM6VV May the Swarf be with you! ------- Date: Wed, 30 Oct 2002 01:47:14 -0000 From: "n2562001" Subject: Re: Drilling angled holes Alan I have always had the best luck when first spotting with a center cutting end mill. I then use a center drill or a spade drill for spotting before drilling. Jerry Kieffer ------- Date: Wed, 06 Nov 2002 17:53:44 -0000 From: "n2562001" Subject: Re: drilling on lathe [SHERLINE GROUP] > I need to drill a hole in a 7" X 1" X 1" piece of aluminum. I do > not have enough room on my mill to do this so the lathe is the > next choice, but what is the best way to do this? There will > be two holes, both off center. I have only +/- .001 error on this part. > Thanks, Devin Devin: It sounds like you are trying to drill holes in the end of a one inch square piece of stock. If so your best chance at proper hole positioning will be with the mill. Turn your head in the horizontal position and put a three inch high piece of whatever under your vice and reclamp to the mill table. You can then hold the stock in the vice and easily position your holes. I just drilled in the end of something three feet long and it worked great. Jerry Kieffer ------- Date: Wed, 6 Nov 2002 13:29:49 EST From: Holyelvisx~xxaol.com Subject: Re: drilling on lathe This is a good idea but, not enough room for this one. The stock is 7", vise 2", 3-jaw 1.5. I believe the room on the 5400 mill is 8". Thanks, Devin ------- Date: Wed, 06 Nov 2002 12:46:39 -0800 From: Alan Marconett KM6VV Subject: Re: drilling on lathe Hi Devin, 7" x 1" x 1"? and you can't do it on the Sherline mill? I'll assume you're drilling into the side(s) of the stock, not trying to drill the ends? I'm thinking your drill bits are too long? It it IS into the ends, then you can probably rotate the spindle to a horizontal position, and clamp the stock on 321 blocks to get them up off the table. Standard "drill index" sets have drills about 5" or so max length, which I routinely use in my Sherline mill. How big are the holes? The boring tool will take you up past something like a 3/8" dia hole, If I recall correctly. I have bought "jobber" bits which are shorter, or cut off/ and turned down the shanks of drill bits to fit my mill/lathe. You can turn the ends of the drill down with HSS in the lathe (just don't let them heat up and harden). IF you need to do it in the lathe anyway (guess you have an 8"+ lathe), then mark the holes, center find them with the part in a 4-jaw chuck or faceplate, and a drill bit in the tailstock. Recent posts on this list on drilling off-center holes in the lathe suggested using toolmaker's buttons. Or indicating in from known edges of the stock to be drilled. Next time this comes up for me, I'm going to locate and drill/tap holes at my locations in the mill, and then used buttons that I've turned and threaded true. Then I can thread them in at the required hole locations, and use a dial indicator to "clock" them in on the lathe. Tell us a little more, I might have missed something in your question! Alan KM6VV ------- Date: Wed, 06 Nov 2002 21:43:14 -0000 From: "lan_brooks" Subject: Re: drilling on lathe A couple more suggestions for using your mill 1) Screw machine drills, also called stub drills are shorter and could provide more clearence and are readily available from MSC and others. 2) If the hole size is under 1/4 in, use the sherline MT1 milling collet to hold the drill. A temporary reducer could be made with a piece of 1/4 inch round bar stock with the right size hole in it for the drill and then slit on one side so it can close when the collet closes. If the hole is over 1/4 inch still use the collet and get a 1/4 in shank drill shortened and sharpened as necessary. 3) If you are drilling in the end and want to use the lathe, make the part a 1/4 longer, chuck in a 4 jaw chuck center as accuratelly as possible. and using a REAL SLOW SPEED so the part does not stand a chance of going anywhere if it does come out, center drill the end. Then using a live center in the tailstock turn a 1/4 in wide round shoulder on the square stock. Use a steady rest to hold the material on round shoulder and drill your hole. Remove the round shoulder with a saw and square up the end. I used the same basic procedure on a piece of rough round stock that was going to be drilled and turned. You are not going very deep with the center drill and if the speed is kept low, the stock will not go anywhere. ------- Date: Wed, 6 Nov 2002 17:00:21 EST From: Holyelvisx~xxaol.com Subject: Re: drilling on lathe Alan, I am drilling the stachions for the overhead cams for a V8 engine. I think turning the head horizontal and putting the vise on some sort of riser block would be the perfect solution.(I am not comfortable chucking up square stock for such close tolerances esp. when the stock is so long.) Devin ------- Date: Sun, 08 Dec 2002 19:14:44 -0000 From: "iamstarvin " Subject: "chatterless" countersink Has anyone found a really chatterless 82 deg. countersink that will countersink a no.6-32 screw. All I have tried chatter at the very end of the job. Any help would be appreciated Steve Livermore Ca. ------- Date: Sun, 8 Dec 2002 14:30:58 -0500 From: "Dan Statman" Subject: Re: "chatterless" countersink The obvious solution is turn down your spindle speed so that the chattering stops. Any bit will chatter at the wrong speed. The art is finding the speed that it still cuts at, and does not chatter. Experiment with it, and I bet in 5 minutes you will be an expert. Daniel J. Statman, Statman Designs www.statmandesigns.com ------- Date: Mon, 09 Dec 2002 01:54:20 -0000 From: "Donald Clement " Subject: Re: "chatterless" countersink I find that M A Ford makes a single flute countersink that doesn't chatter. http://www.maford.com/taf/catalog.taf?category=a11 Don Clement Running Springs, California Owner: Clement Focuser ------- Date: Mon, 9 Dec 2002 22:01:02 -0000 From: "Ted Walls" Subject: Re: "chatterless" countersink I have a number of countersinks. Some home made, some single flute, some with 3, and some with 5 flutes. I don't find any problems with chatter using any of them. The secret is to keep your speed down -- the slower the better, and use some lubricant. I find Rocol RTD paste is about the best for countersinking operations. A small amount applied with a brush to the cutting edges of the tool works wonders. If it smokes you are going at it too hard (using too much pressure) or your revolutions are too high. hope this helps. ------- Date: Thu, 12 Dec 2002 21:54:30 -0800 From: "Orrin B. Iseminger" Subject: Re: Drilling At 08:40 PM 12/12/2002 -0800, you wrote: > Question, I was doing some drilling on the lathe and when I was finished > and took the part out for inspection I noticed the starting point of the > drilling was perfectly centered, but the back of the part that I was > I read the > book and made sure the part had support from both the chuck and steady > I also center drilled the start of the hole so the drill would have > a clean place to start.... > I drilled for a total distance of 3.5 inches > I also made sure to stop ever quarter to half an inch to > I used a dial indicator on the part to make sure it was > I used the drill chuck to > Any help would be great as I try to think of were I went wrong. Welcome to the real world. You probably didn't do anything wrong. Drilling a deep hole, straight, is a challenge for even the best of machinists. There have been numerous threads on the topic on the Home Machinist forum: http://www.chaski.com/cgi-bin/machine_index.cgi Generally speaking, if you need to have a hole straight down the center, do this: 1. Drill the hole first. 2. Mount the piece between centers. 3. Turn the OD. That way, the hole and OD will be fairly concentric. You're not guaranteed of having a straight hole, however. Drilling is a crude process, one of the more inexact machining operations. Orrin Orrin B. Iseminger Colton, Washington, USA So many projects, so little time. http://users.moscow.com/oiseming/lc_ant_p/index.htm ------- Date: Fri, 13 Dec 2002 04:59:00 -0800 From: "Orrin B. Iseminger" Subject: Re: Drilling Make your own dog for large diameter stock. Mine is rather crude, but I just used the materials on hand. Seeing as how it works well, there doesn't seem much need to improve upon it. Cut two lengths of key stock and mill a vee-notch in the side of each, off center. The vee-notches will engage the cylindrical shape of your work piece. Then, drill and tap them with two holes, one on each side of the vee-notch. The holes must be far enough apart to straddle your work piece. Use long screws to clamp your keystock dog onto your work. The reason the notches are off center is to have a leg sticking out to the side. You can drill and tap one of the legs for a long screw that acts as a dog to engage the faceplate; or, drill and tap the faceplate for a long screw that will engage a leg that sticks out. Obviously, some of the holes in the key stock will be tapped for the clamp screws and some will be drilled oversize to allow the screws to slide through the hole. I made my dog with a long leg sticking out on each side. That way it is balanced and will not cause vibration at high RPMs. Orrin ------- Date: Sun, 19 Jan 2003 16:09:19 -0800 From: "Scott A. Stephens" Subject: Re: Re: How can I make a 1" dia hole, 5" deep? At 08:32 PM 1/19/2003 +0000, you wrote: >Scott, I would like to see your pictures. Ideas come from a lot of different sources, and although you probably don't realize it you've already given me something to think about. If you have the time, would you describe your "line-boring" setup in more detail? I'm interested in the details of your between centers boring bar. Did you buy or build, what kind of cutters you use, stuff like that. I haven't had need for that kind of setup as yet but I can see it coming, and would like to put something in place in advance of that day. Thanks, JBK < I got the idea from Jose's video's. Since I had not done it before and only saw pictures of Jose do it, I started with material I had on hand. First the cutter, I used a broken 1/8 drill bit. Believe it was made of HSS. I ground this to a point with a slight hook to break the chips. Next I had some 3/8 rod. I drilled a hole 1/8th hole for the cutter to go through and then drilled a hole for the set screw. Once done I put it on the lathe and center drilled the ends. Problems encountered. Chips, originally I had a problem with chips staying in the hole after they had been cut. I used compressed air to blow them out. That was a mistake since they went everywhere. Also I sprayed in WD-40 to help with the cutting and chatter I had a problem with. But once I found the right speed the feed chatter went away. But I would still spray in WD-40 before each in-stroke and out-stroke. I would run the cutter through twice, an in and then an out stroke before I would advance it. Also I always touched the HSS up with a stone to keep it sharp and cutting. I only used this setup till I had the hole opened up to about .66. Then I switched over to the 1/2 inch bar with 1/4th cutter to bring it out to 1 inch. The half inch with 1/4th cutter was more ridged and seemed to cut better. I still had problems with chips staying in the hole while it was small. When I do it over again I plan to use a vacuum to remove the chips instead of compressed air. ------- Date: Sun, 19 Jan 2003 18:27:24 -0800 From: "Scott A. Stephens" Subject: Re: Re: How can I make a 1" dia hole, 5" deep? At 02:00 AM 1/20/2003 +0000, you wrote: >Thanks, Scott. I'm going to make a couple of different sized bars >along these lines and have them ready for a "real" project when the >time comes. How did you attach the bars to the headstock? Did you >chuck them or use the dead center/dog approach? It probably doesn't >make any difference, but I'd be interesting in knowing what worked >for you. Also, how long did you make your bars? JBK You can do either. I used the dog. Since I had just gotten the tail stock to .001 and was setup for that. My bar was about 14 inches. I can go measure it to give you a precise number. ------- Date: Mon, 17 Mar 2003 14:33:03 +0100 From: Roger Jonsson LINE AUDIO Subject: Re: PCB's >In a message dated 3/16/2003 10:24:34 AM Pacific Standard Time, >frazzxrx~xxyahoo.com writes: >> Has anyone used a CNC to make PC Boards? What tool do you use, a >> regular (but very small diameter) endmill or are there other tools to >> use in the end that would be better? Hi, You should use Tungsten Carbide highspeed drills. (Steel drills will lose sharpness very fast and make bad cuts.) These are available from most suppliers of electronic components. They are usually 1/8" shank and are available in size from 1/50" to 1/8" (0.5-3 mm). These drills require high speed, at least 10000 RPM. Don't try to fasten them them with a chuck, use a milling collet or they might break! If you want to mill tracks or larger holes in PCBs, special Tungsten Carbide mills are also available from some suppliers. I only buy these in Sweden, but it shouldn't be hard for you to find if you look and ask around among the electronic component suppliers. www.maplin.co.uk carries tungsten carbide drills suitable for PCB, in the UK and ship worldwide, but as I said these shouldn't be hard to find anywhere. ------- Date: Mon, 17 Mar 2003 15:08:57 -0000 From: "lan_brooks" Subject: Re: PCB's Carbide router bits are used for the profiling and carbide drills are used for making the holes. The reason for this is that the fiberglass material used for PCBs is very abrasive. Both routers and drills for PCBs can be purchased from MSC . Look for PCB Routers and PCB Drills. Have fun, Lan ------- Date: Thu, 27 Mar 2003 01:01:43 -0500 From: "Ned Carey" Subject: Re: micro size drills and Jacobs chuck runout OK guys, what would be considered acceptable for a Jacobs chuck on the mill? I have some friends that say you should expect the runout to be less than 001". That surprised me, I thought runout would be more in the .003" range, although I can't remember how I came to that conclusion. Does anyone have an Albrecht chuck and have an idea of the runout? This came up on another list in regard to drilling holes in the .004-.008" range so minimal runout is crucial. Jerry Kieffer said the only accurate way to drill micro holes is with a collet. However this precludes using a sensitive type drill attachment. Does the lack of "feel" while drilling with the handwheel cause problems? Thanks, Ned ------- Date: Thu, 27 Mar 2003 18:57:29 -0000 From: "n2562001" Subject: Re: micro size drills and Jacobs chuck runout Ned: I am going to limit my comments to drilling holes under #80 (0.013"). You can get a lot of opinions on this but in the end you will have to develope your own procedures that work for you. There are three reasons I do not use a sensitive drill att. First I have never had a chance to work with one that has less than 0.001" to 0.002" runout when installed on a machine. I am sure there must be one out there someplace, but I just haven`t ran across it yet. 0.002" runout on a 0.006" drill means instant broken drill. The second reason is feed rate control. On a 0.006" or 0.008" drill you're not going to feel much until it's too late. I have found I can slowly nudge the hand wheel 0.001" to 0.002" at a time and eliminate most drill breakage from over feeding the drills. The third reason is the the time and hassle it takes to go back and forth from drill att. to end mills etc. As I said this is what works for me. There is really no wrong way as long as you get the job done. Jerry Kieffer ------- Date: Thu, 27 Mar 2003 21:43:27 -0000 From: "n2562001" Subject: Re: micro size drills and Jacobs chuck runout > Jerry, With drills this size, do you use a "pecking" method, or a > constant pressure? How often do you clear the drill? Do you do any deep > hole drilling (say 10 times the dia. of the drill deep?) Thanks, Wm Wm. There is of course very expensive equipment built specifically to drill holes in the .005" range and down that provides constant pressure on the drill. I prefer to use The Sherline Mill and Lathe to do this work because most small work pieces are machined in this equipment and I don`t like to remove them from the tooling for drilling. The Sherline Equipment may or may not have been designed for this work but has done an excellent job using the procedure I have described. For most holes under five times the diameter of the drill I use HSS spade drills. For deep hole`s I generally use Guhring micro drills (looks like a twist drill but shorter). Depending on the drill size I generally clear the hole every .010" or so. Jerry Kieffer ------- Date: Thu, 27 Mar 2003 19:36:00 -0500 From: "John Thompson" Subject: small drills Wm, We use dremels to drill small vacuum holes (mostly #76 with some #80). We use a fast peck drilling, about the speed of what most people knock on doors, is the best speed I can describe...tap-tap-tap with plenty of lube. This is in Aluminum. I haven't tried it on any kind of press, mill, or lathe, with such small bits. I imagine it would be hard to get the feel of such an operation. Jerry might be able to tell you more John ------- Date: Wed, 2 Apr 2003 15:21:52 -0700 From: "D.W." Subject: rake angle anyone? Just got started on a small pump project (PM Research). The plans state that the rake angle on drill bits should be ground to 0 degrees for drilling brass. I'd be happy to do this if I could just figure out what the heck it means. Thanks in advance, Dave ------- Date: Wed, 02 Apr 2003 19:51:42 -0800 From: Keith Green Subject: Re: rake angle anyone? Hold your drill bit up in front of you so that one cutting edge is facing you and the other is facing away. The one facing you is the one on the left. Looking at this edge, turn the drill counterclockwise 90 degrees and view the edge from the periphery in to the center. You can see that the helix of the drill causes an angle to form there down from the cutting edge. To drill brass or bronze, you want to grind a small flat there on that edge to take away the angle. When you look in from the periphery to the center the area there below the cutting edge should be parallel with the centerline of the drill instead of curving away with the helix. You'll find the drill doesn't grab at all and the chips are fine slivers(sp?). Use solvent for lube. Keith ------- Date: Wed, 02 Apr 2003 23:00:23 -0500 From: RichD Subject: Re: rake angle anyone? Hi Dave, Holding the drill vertically, point up, rotate the drill such that the eye can look **along** a cutting edge. Now you see the flute is a helix ending at the cutting edge. The angle the flute makes with the top of the cutting edge is the RAKE angle. If you now imagine that the edge is a small vertical flat along the edge, this is zero rake angle and is in fact in line with the axis of the drill. The normal rake angle of a standard new drill is suited for drilling steel and other tough material that needs more of a knife edge to get under the surface. Brass and brittle plastics will drill ok this way, but way too agressively. This is evidenced as the drill edges begin to break through the far side. Grinding a narrow flat on the face of each cutting edge now makes the edges scrape as a cutting action. Brass and plastic machine very well this way and produce clean edges on break through. This called dubbing a drill. The clearance angle is the angle from the edges on top to prevent the edges from dragging and allowing proper cutting action. Here are some references: http://www.tpub.com/steelworker2/121.htm http://www.desktopcnc.com/march02.htm http://www.huntfamily.com/metz/hotips6.htm http://www.newmantools.com/machines/drillpoint.html RichD ------- Date: Thu, 3 Apr 2003 00:20:30 EST From: catboat15x~xxaol.com Subject: Re: rake angle anyone? That is to keep the drill from grabbing the brass. I have found that a light stroke with a hone will do the job and stll leave enough of a cutting edge to use the drill on other materials. As to what it means look at the end of a twist drill and you will see there is an angle where the cutting edge meets the groove in the drill. That defines the rake angle, hard to describe, but turn the drill in your hand looking end on to the cutting edges. That is the part you want to stone or grind a small flat to keep the drill from trying to pull itself into the work. If you have a good drill press and the work well secured, it is usually not needed. But don't try drilling brass with the work held in your hand as the drill will grab and you will have to count your fingers to see how many you left in the swarf bucket. ------- Date: Fri, 30 May 2003 19:19:27 -0000 From: "n2562001" Subject: Re: Quality of Sherline products? [NOTE THE DRILLING TIP FOR SMALL HOLES] I do not work for Sherline and never have. However I have been asked to help out at there booth at the NAMES show in the Detroit area the last few years. For the most part I have been asked to demonstrate the machines and get asked your question about every two minutes. To demonstrate the lathe I generally rip down a 3/4" steel bar to about a .010" pivot .200" long in six or seven passes. After that is complete I drill a .006" in the end of the pivot. this whole process takes about 90 seconds if I am not talking as usual. The .006" drills are spade drills that are ground and sharpened from 1mm HSS blanks using the Sherline rotary table and mill. I have been doing this type of work on my current machines two to three hours a day for the last ten or twelve years with no repairs or down time. I hope will give you some idea as to what the machines are capable of. Jerry Kieffer ------- Date: Wed, 06 Aug 2003 13:39:24 -0000 From: "tnance0913" Subject: Drill point Angle When looking thru machine tool catalogs I see drills bits listed as having a drill point angle of (usually) either 118 degrees or 135 degrees. Having just fallen off the turnip truck, I generally do not pay attention to this property and just buy according to price and manufacturer. Could someone please tell me what difference the angle makes in drilling and which flavor is better for what type of operation? I generally work in aluminum, brass and the softer steels, and sometimes, after an appropriate bit of loin girding, I work with stainless. I drill almost exclusively with the Shereline mill. Is one bit types better suited for my work than the other? Thanks in advance, Tom Nance Corpus Christi, TX ------- Date: Wed, 6 Aug 2003 09:05:29 -0500 From: "Ron Thompson" Subject: Re: Drill point Angle Drill point angle has to do with the material being worked. Generally the harder the material, the higher the angle number, with 118° being considered general purpose. The 135° points are for harder material and will drill slower. Ron Thompson On the Beautiful Mississippi Gulf Coast USA http://www.plansandprojects.com ------- Date: Thu, 23 Dec 2004 10:03:46 -0600 From: Ralph Ferone Subject: Re: understanding drill bits >What is the difference between the 118° and the 135° sharpening angle? > Which angle should I use? From a faq found through Google: The 118° standard (non-split) general-purpose high-speed drills are used for drilling soft or mild materials such as cold rolled steel, aluminum, and wood. A 118° drill point provides good results, but may cause "walking" at the drill point. Commonly, a pilot hole is drilled before using a standard drill bit. The 135° split-point, heavy-duty, high-speed steel drills feature a heavy web construction for extra rigidity. Use this angle with hard steels, stainless steel, titanium and other hard materials. The 135° split-point eliminates "walking" and reduces thrust. It also produces smaller chips that won't clog up the hole. Ideal for hand and portable drills where bushings can't be used. There is no need to pre-drill a pilot hole with the use of a 135° split-point drill bit. Ralph ------- Date: Wed, 24 Sep 2003 02:12:44 -0000 From: "bsswy" Subject: run out on drill press I have a 5/8" drillpress with a #3 Jacobs taper. When I put an indicator on the chuck body I get about .005" runout. When I chuck a piece of rod I know to be true, I get about .015" runout close to the jaws. Obviously it gets worse the farther you go away from the chuck. Is there anyway to true up the jaws? Is .005" runout normal for a cheap imported drill press? How do I remove the chuck if I need to replace it? I have had the drill press for about 20 years and had I known anything when I bought it, I probably would have taken it right back for a refund. I have been putting up with it all these years mainly because I would use it woodworking and it didn't really cause that many problems. Now that I got my Taig lathe and want to start machining the performance is totally unacceptable. ------- Date: Tue, 23 Sep 2003 22:42:46 -0400 From: Stan Stocker Subject: Re: run out on drill press If the chuck is on an arbor that presses up into the spindle you can upgrade the chuck. Most drill presses this size have a MT2 socket in the spindle. If the socket is off center you're out of luck though. Might remove the chuck on it's arbor (use a wedge through the slot in the side of the spindle to knock it out) and clock the bore just to verify it is concentric, and that the problem isn't a poorly fitted spindle. An Albrecht chuck on a loose spindled machine won't do anything other than put a hole in your wallet :-( In some cases, simply cleaning the arbor and socket very well and trying a few positions allows you to tune the runout to a more acceptable amount. Try a few different diameters and see if the runout is fairly constant, if it's all over the place it's almost surely the chuck. If it's fairly constant checking the bore is worth the time. Cheers, Stan ------- Date: Tue, 23 Sep 2003 16:47:57 -1000 (HST) From: Tom Benedict Subject: Re: run out on drill press Mmmmm... Yes, there's some stuff you can do. You can get these tapered forks for removing drill chucks. I've seen them in Enco and MSC. Others likely have them. They fit between the spindle and the chuck, and basically act as a wedge. If you're in a hurry, you can probably make some yourself using some flat stock, a hacksaw, and a file. The shape isn't that intricate (or that critical, as far as I've heard.) Try measuring runout on the spindle itself. If there's enough poking out from behind the chuck, indicate off of that. If not, you may need to remove the chuck first. If the spindle comes out ok, try cleaning the tapered arbor and the tapered socket in the chuck. Re-install the chuck and see how the runout is now. If that fixed it, it was likely contamination where the chuck seats onto the arbor. Next check the action of the chuck. If it's still smooth, the chuck is probably fine. If not, you can replace it or rebuild it. Guy Lautard has an excellent section on rebuilding Albrecht style chucks and Jacobs style chucks in one of his Machinist's Bedside Reader books. (I've been itching to rebuild mine!) If the chuck is ok, the spindle is ok, and the taper is ok, try cleaning out the inside of the chuck jaws. Gunk or swarf up there can throw things off. Once clean, repeat the runout test on a length of drill rod. If it's still off, the jaws may need to be reground. Here's where I start getting fuzzy. I've never done this part, so understand I'm fishing here. Hopefully someone else will have better advice: In order to grind the jaws, you'll need to close the jaws on something that still lets you get up inside the chuck with the grinder. I haven't done this. Ideally you'd like the chuck spinning and the grinder spinning. This makes for a very concentric grind, and takes out a lot of alignment errors. An alternative that probably works well for resurfacing jaws, but I would guess wouldn't do as much on alignment, was also from The Machinists's Bedside Reader: You know those ceramic rods people use for sharpening knives? This one guy mounted one in a four jaw, indicated it true, and verrrrry gently closed down the jaws of the chuck on his tailstock until they contacted the rod. After lots and lots of careful work, he basically ground the chuck true. Again, I haven't tried this so I can't say how well it works. Just on the off chance that you need to true up a chuck that goes on a threaded arbor (like the drill chucks on the Taig lathe), here's a way to make improvements without grinding any jaws: Mount some 1/2" or 3/8" rod in a collet or in the four jaw and indicated it in as true as you can. Leave about 3/4" sticking out. Mount the drill chuck in question on this, and clamp down good and hard. Use a facing tool to skim just enough material from the back of the chuck to true up the flat surface. Re-mount the chuck and check runout. I was able to get my 3/8" Jacobs chuck from 0.005" TIR down to 0.001" that way. (My 1/4" industrial Jacobs chuck has been too good for me to want to try this.) Tom ------- Date: Wed, 24 Sep 2003 12:28:20 -0000 From: "davideggy2" Subject: Re: run out on drill press Disclaimer: I don't recommend this. Having said that, I did try it once. An old timer told me to chuck a piece of 5/8" rod and give it a whack with a hammer on the high side. It worked for me, came to within a few thou. You decide, but all that other stuff sounds like a lot of work on a drill press that's been just fine so far. Dave ------- Date: Wed, 24 Sep 2003 15:27:00 -0000 From: "Joules" Subject: Re: run out on drill press That wedge thing people keep refering too is called a drift key. That should remove the chuck and taper. Inspect the taper on the chuck arbor, is it scratched,gualed or rusty. Use a small mirror and light, check the drill spindle. If that is likewise, you could try gently reaming the spindle (note:- to clean, not to re-form). This will remove the crud and level the scratches. If the arbor on the chuck is in this state, bin it, and buy a new one... If possible use a blank 3mt (I believe that is the taper in your drill) to test the spindle. The blank may need to be trued or checked for accuracy in another lathe first. Joules ------- Date: Wed, 24 Sep 2003 09:46:15 -0700 From: "Nicholas Carter and Felice Luftschein" Subject: Re: Re: run out on drill press As others have said, remove the chuck from either the arbor or the spindle if it is integral. Check the chuck mounting taper for runout, and if it shows more than .001 remove the spindle and retrue on a lathe. A Jacobs brand chuck or similar will go a long way towards eliminating runout. Finally check to make sure there is not much play in the spindle - worn bearings or the hole the quill travels in will give poor performance as well. I am a big fan of old used US made drill presses (I love my Buffalo the best, but the old Delta's are great as well) most have provision for snugging up the quill. See our web pages http://www.cartertools.com/nfhome.html ------- Date: Wed, 29 Oct 2003 19:59:00 -0000 From: "texas_hoppy" Subject: New Sherline User [HOW TO DRILL WITH A LATHE] I want to drill a 9/32 hole in a 5/8 aluminum rod using my Sherline lathe. I have the 3 jaw head and a drill chuck. Both came from Sherline along with the lathe in a kit. I have not used either one yet. I make pens on this lathe and it works great. It looks like I need to mount the drill chuck in the tail post. How do I do this and then more the bit into the aluminum rod? Do I push it by hand? This doesn't seem right to me, but... Or do I mount it some how on the tool holder? Thanks for any help, Larry Reese Kenney, TX ------- Date: Wed, 29 Oct 2003 15:14:42 -0500 From: "Statman Designs, LLC" Subject: Re: New Sherline User You should have a #0 morse taper that fits on your drill chuck, it may have come attached from the factory. This taper slides into the tailstock and is held by friction. The handwheel on the tailstock will feed the drill bit into the workpiece. If it won't feed far enough you can drill the hole as far as possible then move the tailstock by hand and then start feeding it again. Be sure to clear the chips periodically from the drill flutes and the hole. To remove the drill chuck from the tailstock you just back the handwheel all of the way out and it will pop out of the tapered hole. Depending on the length of the rod, it may need to be supported with a steady rest in order to keep it from moving off-center. You also want to center drill the piece before drilling. Daniel J. Statman, Statman Designs www.statmandesigns.com dan.statmanx~xxrennlist.com ------- Date: Wed, 29 Oct 2003 21:55:41 -0000 From: "jeastwoodlm" Subject: Re: New Sherline User I agree with all that Mr. Statman said. In addition: Since you don't seem to have a lot of experience drilling with a Sherline, let me recommend that you practice a bit. It takes a while to get a feel for how to do this well. Some specifics: 1) After chucking your piece and checking it for runout with a dial indicator, chuck a center drill (#0 or #1) in the drill chuck. Move the tailstock close to the workpiece, clamp it, and advance the handwheel until the center drill makes contact. Apply a bit more pressure with the handwheel while rotating the chuck holding the workpiece by hand. This gives the drill a "start". 2) Apply power and slowly advance the center drill, withdrawing frequently and brushing away the chips. 3) Step drill with drills of increasing size to reach your final hole diameter. For a 9/32" hole, I'd start with a 1/8" drill, then a 3/16, then 1/4, then 9/32. 4) Watch for the drill chuck turning in it's socket. This friction fit doesn't work too well on such a small area; once it spins in the socket, it mars the tapers and gets more likely to not hold well next time. Make sure you've twisted the drill chuck into the taper snugly (in the same direction the work turns) before beginning. 5) The speed matters; too fast tends to draw the chuck out of the taper. Start at about 1/3 speed and increase it a bit as you can. 6) Use lubricant; regular cutting oil on steel, aluminum cutting fluid on aluminum. Good luck. ------- Date: Thu, 30 Oct 2003 10:31:28 -0500 From: "JERRY G" Subject: Re: Re: New Sherline User 3. good. Choosing step drills that remove the material that would contact the "web" reduce the drilling force required. 4. A sharp tap with a small hammer or mallet to seat the taper is very effective, but don't hit the drill chuck jaws. Retract them first. Point of Information (Pun Intended) A drill is not a finishing tool for holes. Reamers are to some extent. The most accurate hole finishing is to use a single point boring tool. This will not follow the previous hole but will correct the geometry and can be used to achieve any size. Regards, Jerry G (Glickstein) ------- Date: Thu, 30 Oct 2003 15:23:16 -0000 From: "w1vt" Subject: Re: New Sherline User I had a similar drilling problem--I wanted to make a 0.55 inch hole in a 1.20 inch outer diameter balsa dowel, 2 inches long. Ideally, it fits snugly over a 0.54 inch paper tube. I put a 1/2" brad point drill bit in a 3/8" tool holder. I was going to use a Forstner drill, but the 5/32" shaft was too big for the Sherline drill chuck. I mounted the tool holder on the cross-slide and aligned it visually with the center of a 1.5" square balsa block--then drilled the hole. It popped out of the 4 jaw chuck twice, but I managed to drill a pretty good hole, almost 4 inches long. I then offset the cross- slide about 20 mils to enlarge the hole. I managed to enlarge about an inch of the hole. To complete the hole, I used a rubber mallet to drive a 0.55 OD arbor I machined out of aluminum down the hole. Remember, this is balsa, not steel. I then mounted the arbor in a 3 jaw chuck and turned the 1.20" OD. Not the most elegant machining job, but I got exactly the part I wanted :-). Zack Lau W1VT ------- Date: Thu, 30 Oct 2003 15:53:04 -0000 From: "Glen Reeser" Subject: Re: New Sherline User Sometimes even when you have done all of this right, the drill bit will still wander. If you put the tool post up against the bit near where it enters the hole you are drilling, it will minimize this. You may want to do this with a tool instead of the post itself to keep from scratching the post. I found a 3/8" Jacobs type chuck that screwed onto my 0 morse taper tailstock mount. This lets you chuck large bits with a reduced shank. Glen Reeser ------- Date: Thu, 30 Oct 2003 16:00:52 -0000 From: "texas_hoppy" Subject: Drilling Problem Help I have been thinking about this problem since I posted my help message yesterday. All of your answers helped put it together in my mind. I will try it this weekend. What would some of us do without groups like this or the internet? Thanks Again, Larry Reese Kenney, TX www.shadygrovefarm.com ------- Date: Mon, 17 Nov 2003 15:08:32 -0600 From: "Nance, Tom" Subject: RE: Need help on picking out drill bit set [SHORTER SET FOR SMALL MACHINES LIKE SHERLINE/TAIG] Hi Rick: Short length drill bits are called either "Screw Machine Length" or "Stub-Length" drill bits. MSC has a large selection of Screw machine length drills. Their set of 1/16 to 3/8" by 1/64" bits (from Cleveland Twist Drills) is part # 08372385 and costs $58.48. That may work for you. On the other hand, buying the 13 bits (1/16 to 1/4" Cleveland bits) separately from MSC costs about $20.00. Go figure. You can also buy the 13 bits as an import for about $8.00. Don't know about ENCO. I like Cleveland and Precision Twist Drill as manufacturers. I like Hanson and Greenfield for taps and dies. Tom Nance Corpus Cristi, TX ------- Date: Fri, 28 Nov 2003 03:58:30 -0000 From: "mc_n_g" Subject: Re: Cobalt USA-Made screw machine drills - worth it? "Jason Spangle" wrote: > I'm getting ready to dive into some tool & die work on a very small > scale, and was wanting to know if going with a cobalt material for > screw machine length drill bits would be a good idea? > I can get a 1-60 set for $60.00 new in the USA from Enco, I don't > think the price is bad.135 degree split point is how they are designed. > anyone use these? > I feel the shorter length will help with accuracy, less flexing. My father-in-law has a shop I work in on the side(I have a regular fulltime job). We have always used whatever we could get a good deal on. Sometimes it was definitely not worth it. When it comes to drill bits, depending upon what your use, how often, and what you are cutting, I would recommend bright finish or black and bronze finish for drilling. I regularly work with aluminum (7075, 2024, 6061) and steel (tool, O1, cold rolled, hot rolled, etc.) for plastic injection dies and rubber compression dies. There is a definite difference between good quality HSS drills and bargains. Drill bits is where for the most part you get what you pay for. I do not want to sound preachy on this. A lot depends upon your use and cutting fluids (a must). You may want to try a few bits first to try them out before buying a set. Just buy some regular sizes you use and try them before getting the whole set. I have USA made and imports. The USA made last longer and maintain edge longer. They also cost a fortune. Budgets are sometimes tight and you go with what you can get. Get a set and augment it with packs of 10 for drilling tap holes, critical holes, etc. Hope this helps. mc_n_g ------- Date: Fri, 28 Nov 2003 05:14:36 -0000 From: "Silicon Knight" Subject: Re: Cobalt USA-Made screw machine drills - worth it? A while ago I decided to bite the bullet and invest in good drill bits. I'm using TiN coated screw machine (ie, production length) bits that I buy locally from an industrial supply store. I only buy the sizes that I need when a project calls for it, and for standard sizes I stock up on 3 or 4. Not only is the shorter bit easy to handle on a limited sized mill (I own a Taig personally in my garage, my lab uses a Sherline), but it cuts down on chattering and cuts easier too. On a big machine you can just increase pressure to cut with a slightly dull bit, but the RPM range of the DC motor where drilling occurs (ie, lower RPMs) isn't very torquey and a cheap import bit just isn't worth the grief. Yes, I am paying $2.50 -> $4.00 per drill bit, but I havn't dulled one out so far after a year of playing in the shop. Terence ------- Date: Sun, 14 Dec 2003 21:36:50 -0800 From: "Dave Hylands" Subject: RE: Re: Square holes > Many years ago my dad brought home from his shop an ingenious, yet > simple device they used for drilling square holes. Check out these links for more information on square holes: http://upper.us.edu/faculty/smith/reuleaux.htm http://mathworld.wolfram.com/ReuleauxTriangle.html The second one has a small animation to show you how it works. Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ ------- Date: Mon, 15 Dec 2003 13:47:08 -0700 From: lynn.chidesterx~xxxtp.varian.com Subject: Re: So. Cal New Member and Lathe Owner I want to use the lathe to mill ends of (up to 1") max tubing so I can flush mount them in a "t" like fashion, for building frames. I heard its called "fishmouthing" or "Tube Notching." If this is all you want to do, I'd suggest using a tool called an "Ol' Joint-Jigger". I think Harbor Freight sells a copy. The tool holds the tubing at the desired angle, and a hole saw cuts through the tubing. You just need a drill press, and the correct size hole saw. While the tooling makes the job easier, old time aircraft mechanics did the same thing with hacksaws and files. Lynn C. (in SLC, UT) ------- Date: Fri, 2 Jan 2004 16:20:56 -0800 From: "Patrick Lee Rooney" Subject: Drilling holes Is there a standard procedure for the incremental changes when drilling out a large hole with twist bits? I tend to just jump up a few sizes at a time until the desired diameter is reached. Not very efficient with my time, and I spend way too much time grinding bits. If there is some established procedure, I would sure like to be educated. P.S. If your punch press is rated at a certain capacity, and you try and punch holes in thicker than rated stock, you will break your machine! ------- Date: Fri, 2 Jan 2004 19:25:55 -0500 From: " Rigrac" Subject: Re: Drilling holes Patrick: A little more info req'd. Hole finishing size, and what type of equipment you are performing this function on would be good to start. Ron ------- Date: Fri, 2 Jan 2004 17:17:14 -0800 From: "Patrick Lee Rooney" Subject: RE: Drilling holes Hey Ron....we are building racks and shelving for the new shop. I got a quote from a guy that specializes in shelving and pallet racks, and the cost was really out of sight. I keep thinking I am immune to "sticker shock" at this point, but I never am. Thus, building shelving and racks out of 1/8" and 1/4" angle, 3" channel beams, and 3/4" plywood. I have an "older" punch press rated with the die set for 1/8" max. Punched holes every 6" in the 1/8" uprights with no problems. Then tried punching the 1/4" angle and broke the press. I now have a bunch (100's) of 1/2" holes to drill in 1/4" angle with a single Rockwell drill press. I have spent all day grinding bits, and I just want to be as efficient as possible. I am tempted to weld the beams to the uprights, but know I will regret it down the road when I need to adjust the spacing of the shelves. How would you pro's do it? Thanks for the quick reply. Patrick. ------- Date: Fri, 2 Jan 2004 20:33:37 -0500 From: " Rigrac" Subject: Re: Drilling holes Patrick: Unless Rockwell Drill is of the very small bench top variety you should be able to go 1/2 " with one drill no problem. If that is too much for machine and I think you are finding successive drills "grab" and you lose your edge then try to grind a small relief along "land of drill". By "land" I mean look at point of drill from straight on where you can see included angle of drill grind straight in front of you and can see one flute full at the top and disappearing as it goes down away from you. By small I would say 1/64 to a max of 1/32 flat ground along that edge from center out to edge of drill. This will stop drill from grabbing although it might "chatter" a bit. This chatter will not affect drill hole size although is does feel a little uncomfortable on hands. This process is also what you would do to a drill when drilling brass which will grab VERY easily with a regularly ground drillbit. Try it out and let me know how it works. First try 1/2 hole in one shot though. Not too much speed. Ron ------- Date: Fri, 2 Jan 2004 17:45:57 -0800 From: "Steve B." Subject: Re: Drilling holes > Not too much speed. less than 300rpm and use some sort of coolant....cutting oil at least. ------- Date: Fri, 2 Jan 2004 18:16:22 -0800 From: "Patrick Lee Rooney" Subject: RE: Drilling holes Ron. Do you mean 1/2" in one shot without ANY pilot hole? And yes, successive drills "grab" no matter how much I flood with coolant. I thought I was jumping up in bit size too quickly. The drill press is a large industrial floor model, and can be slowed down to a crawl. I think we were pushing the speed also. I will try the "one shot" approach first thing in the morning (with a fresh attitude). Pat ------- Date: Fri, 2 Jan 2004 21:28:59 -0500 From: "piggy" Subject: Re: Drilling holes put in a 1/2 inch drill and crank it up to about 800 rpm and drill the hole. i drilled 400 holes yesterday with a 13/16 bit and no pilot hole, i use a lagun vert mill and drill holes all day every day...... i run a 1 1/4 bit at 400 rpm ,,,,,,,,, a 1/2 at 1000 or so and i only cool with a squirt bottle with coolant and water in it . this is a production shop i work at part time Don T. EVO Power & Machine www.accessatc.net/~piggy www.snartracing.com ------- Date: Fri, 2 Jan 2004 21:56:10 -0500 From: " Rigrac" Subject: Re: Drilling holes Patrick: That right! I drill 1/2" one shot with a little bench mounted drill press. If you have a center drill (like what you would use on a lathe) you might want to center first. Ron ------- Date: Fri, 02 Jan 2004 23:18:20 -0600 From: Jon Elson Subject: Re: Drilling holes If you have a LOT of holes to drill, and this sounds like you do, get several cobalt drills with split points. These cost only a few cents more than plain HSS, but will WHIZZ through moderately tough material. The cobalt HSS tools are as easy to sharpen as HSS, but can withstand heavy cutting MUCH better than plain HSS. Don't bother with TiN coating, as it will not be there after a regrind. Jon ------- Date: Sat, 3 Jan 2004 04:52:27 -0500 From: Charles Gallo Subject: Re: Drilling holes > Don't bother with TiN coating, as it will not be there after a > regrind. Jon Jon, Actually, the IMPORTANT place for the TiN coating to be is NOT at the point (which, as you say, goes away after regrind), but on the flute, just in BACK of the cutting edge, and that IS still there "post regrind" - sort of. You see, the chips will have been wearing at it, so it's now thinner than it was from the factor, so you will NOT get as MUCH service from the bit until the NEXT grind. At least this is how it was explained to me by the guys from Ghuring Drills. BTW Most of the "inexpensive" TiN coated bits sets you see are JUNK that has been TiN coated to make them pretty. TiN coated JUNK, is well, JUNK. Stick with name brand drills. For some reason, I like C/L and Ghuring. Although NOT appropriate for the shelf job, for deep holes, I've come to really like a parabolic flute. Makes the bit a little weaker in side loads, but then again, you're NOT supposed to be side loading your bits, right? Charlie ------- Date: Sat, 3 Jan 2004 00:07:53 -0600 From: "jerdal" Subject: Re: Drilling holes > Is there a standard procedure for the incremental changes when drilling out a large hole with twist bits? I tend to just jump up a few sizes at a time until the desired diameter is reached. Not very efficient with my time, and I spend way too much time grinding bits. If there is some established procedure, I would sure like to be educated. < Yes there is. If you need a pilot hole, you make it the size of the 'web" in the center of the final drill. Then drill your pilots, and go right to final size. You can do two steps if you make each the size of the web of the next. Nice in production to drill pilots precisely and then just burn thru on another DP with final size. If you have to change drills it's a pain. If you can get away with direct final size, go for it. works best with power down feed, but will work. Problem is the excessive force due to the point scraping and not cutting at the web area. that's the good thing about pilot holes. But split points help fix that. Still takes feed pressure, which is why power feed is nice. If you try to increment up, you chip drills as you start the hole with the next size, and it takes way too long anyway. Speed? Faster. Clamp the work and speed up. A 1/2 inch drill has 1.5 inches hole circumference. So each 8 RPM is a foot per minute. Thus, with a 1/2 inch drill, for a very minimal cutting speed of 40 FPM, you need to go at 320 RPM. Since 80 FPM is more reasonable for HSS and mild steel, 640 RPM is still reasonable for a 1/2 inch drill. Smaller go faster. And in production, wear out drills but get it done faster. Drills are usually cheaper than time, and they can be sharpened. Jerrold ------- Date: Sat, 03 Jan 2004 09:14:13 -0600 From: xlch58x~xxswbell.net Subject: Re: Drilling holes Agree Cobalt will do an exceptional job, but have to disagree with the remarks on TiN coating. The TiN coating is still on the cutting edge after a regrind if you are grinding your drills correctly. The front face of the Flute is what is cutting, what you are grinding is the face of the tip, or the clearance angle. Regarding the original posters question about stepping up in drill sizes, only two drill are really needed and one if you use a splitpoint drill as Jon has suggested. The reason for stepping up in drills other than accuracy (not an issue in this case) is to account for the small area of a standard drill that doesn't cut. If you look at the tip of a standard ground drill bit, you will see that the cutting edges do not meet at the point, instead, there is a small pointed area. During drilling, this area just wears its way through the metal and creates heat. You need to select a pilot drill that is larger in diameter than the width of this non cutting area on you final drill. The pilot drill should be as small as possible so that the non cutting area on it is as small as possible. 135 degree split point drill solves the problem by making the cutting edges meet in the middle. Nifty solution, but they will not track a punch mark as well. Charles ------- Date: Tue, 17 Feb 2004 23:29:20 -0600 From: "jwalters" Subject: Re: Drill Bit Recommendations? Brass. Aluminum and Steel each work best with a different type of drill bit. Brass cuts best with a drill with a modified cutting edge, a small neutral angle flat ground on the cutting edge. Most grades of brass do not cut good with a sharp edge, a sharp edge causes the drill to bite into the material creating chatter. Black oxide bits work best on steel and shiny bits are best for aluminum. Cobalt bits are generally high quality and expensive and are intended for harder grades of steel, with a TIN coating cobalt bits are good for most materials. Hard brass still works best with a neutral flat on the cutting edge. Cast Iron cuts best with a black oxide bit or expensive carbide grades. In a production environment, solid carbide or carbide inserted drills with grades optimized for an application are used. In reality a home shop machinist can drill most materials with whatever drill is available. Just to through in an additional style, parabolic flute drills are best for drilling deep holes. Letter drills are frequently needed to optimize tap drill hole size to optimize thread fit. I hope this helps. John Walters ------- Date: Wed, 03 Mar 2004 12:47:14 -0500 From: RichD Subject: Re: Spotting drills? A good spotting drill (some are just very short drills) has no pilot tip like a center drill has and comes to a very small point. That is, the chisel tip as found on drills is extremly small. This is the correct type of tool to use for "spotting holes" for accurate part layout used in conjunction with x - y movement and a DRO or CNC. The basis for its use is to provide a rigid accurate starting point to help control the starting of the following drill procedure. A center drill will also "spot holes" but takes considerably longer and there is the habit of the tip breaking off in the work. Use these tools with cutting oil. The pilot tip of a center drill can be used for a spot drill and works well for a lot of cases, but the chisel point is the same as a normal drill. For small holes to drill, a very small center drill would have to be used or you find the drill wandering on the flat bottom left by the center drill tip. For larger drills, it's better to drill deeper to "spot" with the 60 deg cone part of the center drill. That takes more time and a lot of material has to be removed burying the pilot tip and if not careful, choking it, resulting in a broken tip buried in the work. Be careful, retract often. Spot drills have the same included angle as a drill point with very small tip geometry. A much better matched depression is left for the drill to follow and you can chose a depth you need to suit the drill diameter. I use a 1/4" spot drill exclusively for all sizes down to #60 drill. The center drill tip is to give clearance for the actual lathe center tip. It's not a good idea to have a lathe center bearing on its very tip. Down the shank a bit spreads the load out giving a larger bearing area. Yep, some lube in the hole will help as well. RichD ------- Date: Fri, 19 Mar 2004 22:21:41 -0000 From: "tsterling2000" Subject: Short, stiff small diameter drill bits My wife makes small art baskets and uses my Sherline equipment to make rims and bases for them. We've recently run into problems drilling small diameter holes (in wood) without the bits wandering. Does anyone know of a source for short, stiff small diameter (under 1/8 inch) bits in graduated sizes? Regular (as in hardware store) bits aren't stiff enough and easily wander half a diameter off in very short distances. Who would have thought it was harder to drill good holes in black walnut than in steel? If you'd like to see what I'm talking about, visit our web site at http://www2.whidbey.net/netsuke/ and click on the Containers for the Soul Art Baskets link. Thanks in advance. Tom Sterling ------- Date: Fri, 19 Mar 2004 17:42:02 -0500 From: RichD Subject: Re: Short, stiff small diameter drill bits I would suggest PCB carbide drills, but you will have to see if the typical short flute lengths will do. The shanks are all 1/8" dia. Also, in small sizes, anything tending to defect them will snap them off. OTOH, I use a No. 38 to drill down the side (partially into) of alum. heatsink fins by the 100's with no problems. CNC controlled. RichD ------- Date: Fri, 19 Mar 2004 18:01:05 -0500 From: "Jerry Glickstein" Subject: Re: Short, stiff small diameter drill bits Go to MSC Direct, (Google) and the items you want are "screw machine length twist drills". There are many manufacturers. Always centerdrill first to start the hole where you want it. #00 have .025" pilot drill diameter with a .125" shank. I have also reduced the pilot diameter by grinding the OD. Regards, Jerry G (Glickstein) ------- Date: Fri, 19 Mar 2004 23:52:37 -0000 From: "n2562001" Subject: Re: Short, stiff small diameter drill bits I have had this problem for years. Drills tend to follow the grain of most woods. The best solution I have found is a center cutting end mill at high speed if they are the right size and long enough. The second best is a sharp standard twist drill held in a WW collet with only the depth of the hole exposed at the highest possible speed. Jerry Kieffer ------- Date: Fri, 19 Mar 2004 17:13:34 -0800 (PST) From: Henry Flymo Subject: Re: Short, stiff small diameter drill bits Something you could do is grind a simple spade drill. Use drill rod that is what ever size hole you want and grinde it flat 1/2" up on both sides evenly to the thickness of the end of a screw driver. In fact it will look like a screw driver. Next grind it the other way to make it into a centered point 80 to100 degrees included angle. And last put 5 degrees relief angle on each flute and make sure angle is leaving leading edge for right hand revolutions. ------- Date: Fri, 19 Mar 2004 19:19:06 -0800 From: "David" Subject: Re: Short, stiff small diameter drill bits Is there a good reason that you're not prick-punching and center-drilling before you drill? Dave Wood ------- Date: Fri, 19 Mar 2004 22:50:43 -0500 From: "Jerry Glickstein" Subject: Re: Short, stiff small diameter drill bits Dave, offhand, I would avoid prick punching in wood. Violent and upsets the fibers..... Regards, Jerry G ------- Date: Sat, 20 Mar 2004 04:50:56 -0000 From: "n2562001" Subject: Re: Short, stiff small diameter drill bits Jerry, I don`t think center drilling wood will resolve Tom`s problem. At least it has never stopped small drills from following the grain when I have center drilled first. Jerry Kieffer ------- Date: Fri, 19 Mar 2004 19:26:27 -0800 From: "Marcus and Eva" Subject: Re: Re: Short, stiff small diameter drill bits One of the best ways to keep a drill from wandering in wood, is to modify the point to a brad point with a peripheral scoring chisel on each flute. Look at woodworking bits like Forstner bits to get an idea of the desired geometry. This shape can be a bit of a challenge to produce in a tiny drill, but with a clever setup in the mill or the lathe it can be done. The problem with wood is that it has both hard and soft grain strata that lie adjacent to each other. So even if the drill is sharp and started correctly in a center drilled hole it will wander as soon as it hits a hard stratum only on one side. Putting the Forstner bit geometry on the tip, alleviates this somewhat by removing the wedging effect produced by a cone pointed twist drill. It will be self guiding because of the two scoring chisels on the periphery, and the flat bottom tends to minimise side forces caused by uneven hardness of the wood. In fact, the principle is similar to that which Jerry Kieffer exploits when he uses an endmill. The flat bottom minimizes wander (as does the stubby length). Cheers Marcus ------- Date: Fri, 19 Mar 2004 22:48:42 -0500 From: "Jerry Glickstein" Subject: Re: Re: Short, stiff small diameter drill bits Marcus, you have put your finger on the problem. The material to be drilled is part of the system. However, another solution occurs to me depending on the application. It is a cheat, of sorts, but it will work. Centerdrill, drill and bore for larger plugs that are drilled out in the lathe, and then pressed and/or glued in place. Single point boring (for the plug) is the really accurate way to prevent wander, bad geometry, etc. There is ALWAYS another way. :) The tip modification (chisel points)is almost impossible in really small drills. Regards, Jerry G (Glickstein) ------- Date: Sat, 20 Mar 2004 15:10:51 -0000 From: "n2562001" Subject: Re: Short, stiff small diameter drill bits Jerry, what I am referring to is drilling with both the mill and lathe. I always center drill but only to position the tip of the drill as you would do in metal. Small drills will almost always follow the grain unless held very short and ran at very high speed. My big headache machining small handles for scale tools and then trying to drill a hole down the center for mounting. I no longer even try since it is faster to drill a hole in oversize stock and put it on a mandrel for turning. If you put a piece of hard wood in your lathe and try to drill a small hole through it, it won`t take you long to figure out what I am referring to. (Unless you get really lucky) Jerry Kieffer ------- Date: Sat, 20 Mar 2004 07:47:57 -0800 From: "Marcus and Eva" Subject: Re: Re: Short, stiff small diameter drill bits Hi Jerry: Have you ever tried brad point drills? Not perfect, but quite a bit better than conventional metalworking twist drills. I grind the points on the tool and cutter grinder on the rare occasions where I need one, but I'm sure a stoning jig with roller followers (bit like a filing jig for the lathe) could easily be made up for tiny drills, and those with no cutter grinder handy. Cheers Marcus ------- Date: Sat, 20 Mar 2004 16:27:17 -0000 From: "n2562001" Subject: Re: Short, stiff small diameter drill bits Marcus, I think I have tried just about every kind of point including various spade drill modifications. While some points work quite well with larger drills, nothing seems to work with drills under about .100". It seems that the hole will be no straighter than the grain of the wood. Jerry Kieffer ------- Date: Sat, 20 Mar 2004 09:59:34 -0800 (PST) From: Scott Meyer Subject: Re: Short, stiff small diameter drill bits Interesting. I have worked in a few tool rooms, die shops etc. I have never done both prick punch and center drill. If I prick punch, I'll put a small drill in the chuck on the drill press and move the vise until the drill doesnt flex into the punch crater. Change drill to the proper size and drill. If I need an accurately located hole, I'll put it on the mill and use an edge finder (usually) to locate the hole, and then center drill it. One thing that I was taught, is that prick punching isn't very accurate. The width of the scribed line, the parallax error from being unable to look straight down where the punch is pointing, the relatively broad point of the punch, etc. Just seems to me the more operations you do to drill a hole, the more inaccurate you are. Tolerance stacking - ie error in layout, added to error in punching, added to error in centerdrilling, added to error in drilling, makes a pretty big margin for error. I try to centerdrill everything. If I use a transfer punch or something, I'll use a pointer to locate the hole if I need any accuracy. A center drill is stiff, and doesn't flex like a drill will. Just a comment about the included angle of the points involved (the punch and drills, not the discussion points). A typical drill has a 135 deg point. I don't know what a typical prick punch angle is, but it only lasts until someone sharpens the point on a grinder. I have never ever heard of anyone setting up a cutter grinder or something to maintain the angle on the prick punch. They take it to a pedestal grinder and offhand make it pointy again. The centerdrill has 2 angles, a 135 deg point, and a 60 deg. When I centerdrill, I only use the 135 point, which matches the drill point. If I drilled into the 60 deg, I would only be locating off a small ring, and not a larger surface. Has always worked for me, not saying other ways don't work. Scott ------- Date: Sat, 20 Mar 2004 13:14:12 -0500 From: Stephen Brown Subject: Re: Short, stiff small diameter drill bits I prefer brad point bits for accurate hole drilling in wood. Lee Valley sells good HSS bits down to 5/64". You can get stub length ("screw machine") twist drill bits from any good tool supplier (e.g. MSC, McMaster-Carr, Enco, &c.) but I think you'll still have trouble drilling straight holes, I think. You need a point geometry that doesn't get deflected by the wood grain. Lee Valley re-grinds their brad point bits from regular jobbers length twist drills, so they're regular length, but you could always cut down the shank or bury most of it in a collet or custom holder. But I think you'll find good brad points bits will do what you want. Steve Brown ------- Date: Sun, 21 Mar 2004 23:17:01 -0800 From: "Marcus and Eva" Subject: Re: Re: Short, stiff small diameter drill bits > The largest we've used sop far is about 3/32 inches, and we go > considerably smaller than that. 3/32 isn't too bad about wandering, > but smaller sizes are. We've had some luck with a few odd looking > carbide bits I came across in a one time surplus sale. Tom Sterling The carbide drills you found were probably circuit board drills. They are intrinsically stiff, being made of carbide, but some brands have such deep flutes ground in them that they become quite flimsy and will break very easily. Most of the major tool suppliers stock them; I've bought them from KBC in the past. You may be better off with carbide spotting drills; I'm not sure though, whether you can get them easily in small sizes. The brad point style is still superior for woodworking if you can find or make them. The faster you can spin them the better too. You'll need to peck drill; don't try to go all the way through in one shot, unless your hole is no deeper than 1 1/2 times the hole diameter. If you're doing this on a Sherline mill, you should get the 10,000 RPM pulley, and the sensitive drilling attachment; it will make your life MUCH easier. If you're well off financially, it would be very worthwhile to purchase the Sherline CNC rotary table too, or join the CAD CAM EDM DRO list and learn how to make your own from the existing turntable you already are using. It's not difficult, and it's much less expensive than buying the Sherline version, but the Sherline is a good unit for this application and has some nice features. If you're doing this a lot, and your work is commercial (and can justify the expense), you might need to invest in the means to be able to repoint your own drills too...it's not difficult once you have the tools, and have learned how to do it. A diamond cup wheel and a moderately ingenious fixture will set you up nicely to do it on the mill. Cheers Marcus ------- Date: Tue, 30 Mar 2004 15:01:57 EST From: toolroomtrusteex~xxaol.com Subject: Hole saws for drilling [Metal_Shapers] dreilanderecht wrote: //Are you onto the technique of using hole saws? The decent HSS ones, not the cheapies from the hardware store. These can be used to make a hole, they can usually go in about 1.5 inches, so going from each end you can get a hole through a three inch thickness of metal, and you get a potentially useful round piece from inside. You can also use them the other way around, eg put it in from the end and then a parting tool from the side to take a ring off. You naturally need to put a boring tool through afterwards when you are making a hole, but it can save a lot of time.// John: That's a great idea! I assume you'd still have a hole in the center of the hole sawed out plug from the pilot drill but that wouldn't necessarily be a problem. Larry ------- Date: Tue, 30 Mar 2004 14:27:19 -0600 From: "Brian Alley" Subject: Re: Hole saws for drilling When I do this i do not use the pilot drill. Either run the hole saw in the tailstock or mill head and I find it sturdy enough to do the job. brian. ------- Date: Wed, 31 Mar 2004 02:24:20 -0000 From: "dreilanderecht" Subject: Re: Hole saws for drilling As Brian says, you don't always need the pilot drill...I tend to leave it in if I have no specific use planned for the slug from the centre, but with a rigid setup like a lathe or mill it is not needed. regards John ------- NOTE TO FILE: This next message veered off the original thread topic in the sherline group and has been arbitrarily placed here to also help readers using other machines. Date: Sun, 8 Aug 2004 10:42:33 -0700 From: "Marcus and Eva" Subject: Re: Re: Tail Stock Original Message ----- From: "Jerry Glickstein" To: Sent: Sunday, August 08, 2004 3:23 AM Subject: Re: [sherline] Re: Tail Stock > Scott, As you should know working in a machine shop, > drilling is a roughing operation. Reaming is a semi- > finishing operation. The only really accurate way to make > a hole or bore is with a single point tool such as is > done in boring. And then, the tailstock doesn't even > have to be on the lathe. Lapping and honing can refine > the finish of a hole, but the geometry is the key. Hi Jerry: Thank you for pointing that out. Many, many people who should know better, fail to make that distinction and are disappointed when their projects don't work quite as well as they envisioned. I've seen countless articles by so-called "experts" who pretend they've achieved a precision hole in an accurate location, by centerpunching to scribed lines, drilling and reaming. I've also seen a terriffic amount of nonsense about setting up to prick punch marks with a wiggler, pounding in a drill, and then claiming that the hole needed to be very accurate, and "look at all the stops and clamps and whatnot" that insured I'd have a predictable outcome. For the record, my thumbnail rules are as follows: -A drilled hole will be oversize always...how badly depends on a lot of things, but a poorly ground drill makes the biggest contribution. -A step drilled hole will be better if the last step removes no more than 5% of the final diameter. (that's about 0.010" for a 1/4" hole) -Reaming can get you pretty good for size and roundness, but only if you pay close attention to lots of conditions. -Good finish is difficult to achieve with a reamer in many materials. -Poor initial location is not improved by reaming. -Boring can readily improve hole location, as well as hole roundness and straightness. -Size control is difficult to achieve routinely during boring if you need to split thousandths. -Boring and lapping gives best size and location control in the average home shop. -Center punching to scribed lines will get you within 0.010" routinely if you're very careful, and within 0.025" if you're even just a bit sloppier. -A drill press is good for making the mounting holes to bolt the bumper onto your car. -Edge finding and center drilling will get you within 0.002". -Toolmaker's buttons & boring in a turret mill can get you within 0.0005" -An accurate jig grinder and in-process gauging can get you within 0.0002" -Wire EDM can get you within 0.0001", but very few machinists can measure that close without lots of expensive gear and a climate controlled inspection room. -Placing the hole first, lapping to size and then finishing the block to the hole can get you within 0.00005" -Luck can get you closer. -Bullshit can get you to pretend that you're closer. Please feel free to add to the list, or edit it to reflect your own experience. I think it might make a good reference chart for guys to keep around when they're reading articles or project plans. Maybe we can do one for "rules of milling" too. Cheers Marcus ------- Date: Sun, 8 Aug 2004 17:26:43 -0700 From: "Marcus and Eva" Subject: Re: Re: Tail Stock Original Message ----- From: "George & Cathy Dunham" To: >>>I have a mill. Maybe I've not made myself clear enough. I use the T.S for drilling the end of clock arbors to receive new pivots. (.055" and smaller) The over-size I speak of is more accurately described as cone shaped with the outer edge not exactly round. This results in poor support for the new pivot making it difficult to press it in solid and keeping it in truth. My results are far more consistent since I've made the adjustments. I understand I may be missing something, so I'll ask: How would you "bore" a blind accurate .050" hole .35" deep, dead center in a .110" mild steel arbor. (Wheel and pinion still attached.) Mill or lathe either one. I'm always eager to improve my skills with these tools. Thanks! Regards George Dunham <<< Hi George: Boring tiny holes is very dependent on your ability to make and set up small cutting tools. As you've experienced, judging from your posts, the devil is in the details on small work in quite different ways than it is on larger work. A useful way to make judgements about depth of cut and amount of clearance etc, is to look at them from the point of view of percentage of feature size. To bring this into perspective from your question regarding boring a hole 0.050" diameter and 0.350 deep, consider the following: If the hole were scaled up 10 times, it would be a half inch hole, 3 1/2 inches deep. To make the big hole, you'd drill to say 7/16" and bore the first inch out to 0.490", using a bar about 0.375" diameter, set to center within 0.010". You might take passes of 0.010" and a final kiss pass of 0.002". Once you're at 0.490" for the first inch, you'd take a 0.490" reamer that has had the cutting edges reground so they're not chamfered, but look like the flutes on a milling cutter. You'd use the 0.490 bored hole as your pilot to straighten the remaining 2.5" of the hole depth. Now you could bore the first inch to 0.4995 or 0.4997, and then run a normal 0.5" reamer down the hole. If you needed better than you could produce with a reamer, you'd bore and ream to 0.498 or 0.4985 and lap or hone to size. Using this admittedly elaborate protocol, you'd have good size control, good roundness, good concentricity and good hole straightness...if you honed, you'd have better size, roundness, parallelism and finish, but not better concentricity. You'd also have a bit at the bottom of the hole you couldn't hone, and this bit would remain undersize. Translate all this to your proposed hole by dividing everything by 10. Note that this means you're boring a hole 0.100" deep with a 0.038" diameter bar, and your ROUGHING pass is 0.001"!!! Your tool point needs to be in position within 0.001". Implied also, is that a 0.001" error on the flute geometry of a 0.050" drill is "equivalent" to a 0.010" error on a half inch drill Where, in the name of all the Machinist's Gods, do you get a 0.038" boring bar??? The answer is; you make one, and you make a 0.049" reamer too! This is part of the fun and the challenge of machining, and once you understand the principles involved, it's not difficult to do. Now granted, there are other ways of approaching this problem, and the basic physics involved is somewhat sensitive to scale, so you couldn't realistically do this for a 0.005" hole. But the mental process is a useful one, and can help to point you in a direction that will be successful. The principle of getting the first part of the hole straight by single point boring , and then using this as a quick and dirty "drill bushing" is a very useful one when you need to care a lot about the position and geometry of the hole. So is the principle of reducing the tendency of a reamer to follow an existing hole by knocking off the chamfer and re-shaping the cutting edges to mimic a milling cutter. Of paramount importance, though, is recognizing that a 0.001" error in runout of a 0.005" drill is vastly different in consequences than a 0.001" runout error in a 0.050" drill or in a 0.500" drill, and it's helpful (at least to me) to think in terms of percentages. So the 0.001" runout is a 20% error in the small drill, and only a 2% error in the 0.050" drill. That's not strictly true, but it's useful nonetheless. Cheers Marcus ------- Date: Mon, 09 Aug 2004 02:26:43 -0000 From: "n2562001" Subject: Re: Tail Stock George, if I understand this, you are drilling a hole and inserting the exact size pivot needed in that hole. If so I have personally found this to be very difficlt to do. First clock arbors tend to have hard and soft spots as well as just plain poor quality steel in some cases. For that reason it is difficult to drill a hole that will be perfectly centered no matter what the equipment or tools used. Of course you can bore the hole but this is very time consuming for a proper friction fit. For pivots that are under 1/16" I first center drill with a #1 center drill. From that point I drill a .055" hole at least .375" deep or whatever the arbor will allow and then ream to .061". Next I put a piece of 1/16" A1 drill rod in the tailstock drill chuck with the tailstock left un-tightened to the bed. Next with the arbor turning very slow in the headstock chuck I slide the tailstock with the drill rod up to the hole and push it into the hole with light pressure. The rotating of the arbor will suck the drill rod into the hole and make a very nice accurate friction fit. You can feel when it seats at the bottom of the hole and turn the lathe off. From that point the drill rod is trimmed for length and machined down to the size needed and polished. This will give a straight round accurately centered pivot. By using A1 drill rod the pivot can be flame hardened if desired or needed. I have demonstrated this method at several Regional watch and clock shows over the years without any reported problems. Jerry Kieffer ------- Date: Wed, 17 Nov 2004 18:33:40 -0000 From: "n2562001" Subject: Re: Circuit Board Drills > These are carbide drills, sometimes very small (below #60) with short > cut lengths (<1/2") and oversize shanks (e.g.1/8"). They are made to > turn at very high speeds (40-100K rpm) and are highly intollerant of > flexture. Has anyone had any success (or abysmal failure) using them > with a Sherline mill, say with the sensitive drilling attachment and > at the highest speed? Mike Mike, drilling small holes down to .002" and sometimes under has been a long hard row to hoe for me over the years. Opinions have been abundant however demonstrations have been almost non existent. Sometimes you just need to jump in and develop your own methods. I have used carbide circuit board drills over the years with very little problem in most materials. The first thing you will learn is that they must run true. For this reason I only mount them in WW collets. Next they will break if the feed rate is not controlled. Personally I have found that I get better control with the standard hand wheel than with a sensitive drill attachment. To manufacture a sensitive drill attachment that is accurate and sensitive enough for drills under .010" would probably cost several hundred dollars. Or more time than I want to spend building my own when it is not needed. The most important thing when drilling small holes is to be able to see how the drill is reacting to the material you are drilling. When I mounted my Ziess stereo microscope to the mill and lathe several years ago, 95% of my small hole drilling problems as well as many others disappeared. Under QUALITY optics of 6x-8x drilling a .002" hole is like drilling a 1/2" hole without magnification. #60 carbide drills should be no problem in the Sherline mill at high speed as long as they run true. If you have a problem watch the drill through a eye loupe while drilling and you will find the problem. Jerry Kieffer ------- Date: Thu, 18 Nov 2004 21:12:15 -0000 From: "n2562001" Subject: Re: Circuit Board Drills Bill and Mike: Unfortunately I do not have a digital camera to take pictures of the microscope mounting. Craig at Sherline has also asked and I plan on having some taken that will be put on Sherline's workshop tip site in the near future. For those interested in Microscopes I can offer a couple of comments. First poor quality Optics are worse than no Optics at all. They will distort the work piece size, shape and tool position as well as damage your eyes in some extreme cases if used on a regular basis. To be blunt I am talking about inexpensive Optics from China, India, etc. For these reasons I no longer use anything other than German Mft. Zeiss or Leitz Optics. I fully understand that most people will not pay the price for this type of quality. For those who are looking for something usable at a reasonable price I recently purchased a used current Mft. Russian Stereo microscope at a price I could not pass up. It came with three sets of eye pieces with total powers of 3.3x to 14x typically used for machining. I see that they are being sold on the internet under the name Lomo model Sf-100 for about $500.00. I have been very impressed with the optical quality of this unit. The image is as sharp and clear and seems to have less distortion than current production Nikon, Meiji etc. costing upwards of $2500.00. For anyone on a budget this would be a good unit to check out. I would strongly suggest looking through any microscope before purchasing it. Always pay attention to the working distance (minimum 90mm) you will need and the availability of a protective objective lens. Most of the time a clear camera filter lens can be adapted for this purpose if not offered. Also make sure the field of view will cover your work area and that the image is sharp out to the edge. Jerry Kieffer ------- Date: Thu, 18 Nov 2004 15:59:56 -0600 From: "Gordon Couger" Subject: Re: Re: Circuit Board Drills Jerry, I know a dealer that has AO Spencer Cycloptic that have been cleaned the prism all redone with modern cement with a one year warrantee for about $200. These are old scopes but are built like tanks and are brighter than any but the most expensive Zoom scopes. I have 2 and like them better than anything but he top Zeiss and Nikon scopes that cost over $800 on ebay with no service, cleaning or guarantee. Well over $1.000 from a dealer. The Cycloptic is all metal and will last for another 50 years if the prisms are attached with modern cement. They are the best buy I know of. You can buy them on ebay for $40 to $100. See: http://www.microscopyu.com/articles/stereomicroscopy/stereointro.html I got the last one from Arthur Rosenfelder at http://www.roseoptics.com/ Gordon Couger I collect links on information related to light microscopes. http://www.couger.com/microscope/links/gclinks.html Please forward any links or information you think might be useful to others. Microscope Manuals at www.science-info.org ------- Date: Thu, 18 Nov 2004 23:18:52 -0000 From: "n2562001" Subject: Re: Circuit Board Drills Gordon, I will agree with you 100% that there are many great deals on used stereo Microscopes in the market place for those familar with Optic`s. There is a local Microscope repair place here that regularly has used serviced Nikons for $250.00-$450.00 as well as many others. (I am not a Nikon fan.) The problem is to find a unit that has all of the needed parameters for machining and mounting. I personally prefer the boom type mount for flexability when mounting to a machine. As I mentioned there are other considerations such as low power settings, field of view, working distance etc. None of this is a problem for those familar with microscopes. However for someone who is not all of this can be a nightmare. If you don`t have the time or desire to become familar with optics the unit I suggested looking at covers all of the considerations needed for machining. It is available and a place for a beginner to start looking and compare with other available units. Jerry Kieffer ------- Date: Thu, 18 Nov 2004 23:16:20 -0600 From: "Gordon Couger" Subject: Re: Re: Circuit Board Drills Jerry, in general I do think a lot of Nikon microscopes because the good ones came along after everyone started using plastics in their scopes and the scopes in the price range that amateurs can afford have problems with the plastic gears. The newer Nikon scopes are competitive with everyone else in quality. Nikon did make a very good stereo microscope and the optics are equal to anyone's. To put on a lathe or any other tool I like the older scopes with out zoom optics because they have a brighter image and are more tolerate of the environment for shop work than the more expensive zoom scopes. Most scopes will need a 1/2 x auxiliary lens to get the magnification down to 3.5x to 15x as well as the standard 7x to 30 x for more flexibility. All the brand name scopes can be found with a choice of ways to mount them. I agree that a boom stand is best for all around work in the shop. I will be glad to work with anyone off list about working there way through the maze of options and choices. I don't have any connections with commercial sales of microscopes so I am not trying to sell them. They are the preset I am most interested in and only have a lathe and mill to make parts for them and projects for them. Gordon ------- Date: Fri, 19 Nov 2004 16:34:11 -0000 From: "n2562001" Subject: Re: Circuit Board Drills Gordon, it sounds like you're into Microscopes and quite knowledgeable about the subject. In fact all of the local Microscope people agree with what you are saying. They hate to see me come and only speak when they need something machined (as cheaply as possible of course). My only interest in the scopes is for machining with a power range of about 3X to 10X. On the lathe they are mounted on the cross slide and on the mill they are mounted on the head. The reason for this is so the scope will track the cutting tool. From time to time I also use a lens scale and this movement allows measurement while cutting. I prefer a scope with multiple power settings or a zoom scope so that I can maintain a constant working distance and change powers as needed while machining. Most scopes I have seen when installing or removing a .5 or other supplemental lens will change the working distance. Since I change powers like I change spindle speeds it is important to have constant working distance over the power range that I use. A constant working distance also simpilfies mounting. I have an older Zeiss with no model marking and a newer Zeiss Stemi-2000. I judge all scopes by the performance of these scopes because I have not personally looked through anything better. The local Microscope people always tell me that the Nikons and others are just as good but since I have not been able to see it, my eyes must be screwed up. For this reason I have always suggested looking through any microscope before purchase. I really like the Stemi-2000 because it is light weight, easy to clean and is sealed better than the older scopes. The only problem is of course the price. If you need a microscope I think you would agree, take your time and buy the highest quality you can afford. Jerry Kieffer ------- Date: Tue, 30 Nov 2004 18:52:23 EST From: wanlikerx~xxaol.com Subject: Screw Machine drills I find that the screw machine drill sets are extremely handy with my smaller lathe, and mill, and would recommend them to all. I have had no success in finding a Metric set in screw machine length. Anyone have a SPECIFIC SOURCE, for such a set? I have searched most online catalogs and no happiness, so would like a specific URL if anyone has one. Thanks, bill ------- Date: Wed, 01 Dec 2004 00:17:04 -0000 From: "Jim Knighton" Subject: Re: Screw Machine drills These might not be what you are looking for since they aren't screw machine drills. These are smaller. These drills are solid carbide and perform best when run faster than a normal twist drill. I've had best results at about 2000-2500 rpm in both mild steel and non ferrous metals. All are 1.5" long and with 1/8" shanks. I have fractional and number sets of these drills and have found them to be of excellent quality. Their small size has much to recommend them on small machines like Taig or Sherline. http://www.store.yahoo.com/drillcity/25milset.html Regards, Jim ------- Date: Wed, 01 Dec 2004 00:43:19 -0000 From: "n2562001" Subject: Re: Screw Machine drills Bill, MSC has screw machine drills in metric from 1.0mm and up as well as proper fitting index cases. ( 800-645-7270 ) Jerry Kieffer ------- Date: Tue, 30 Nov 2004 20:23:34 -0600 From: "Martin Dobbins" Subject: Re: Screw Machine drills Bill, you might try Mc Master Carr, they have metric screw machine bits from 1mm on up. http://www.mcmaster.com/ Martin ------- Date: Sat, 29 Jan 2005 00:46:34 +0000 From: Steve Blackmore Subject: Re: Centre punching/Drilling On Fri, 28 Jan 2005 14:52:42 -0800, you wrote: > Each part needs two 1.3mm holes drilled. It is not practical to >centrepunch the drill spots, but there must be a " usual method " of >doing this with a CNC mill. Is it to touch the surface with a larger >drill that will not deflect, and make a start for the smaller drill? How >do people usually do this? Short drill bit known as a "Stub drill" over this side of the pond. Don't forget to run drill fast - about 4000rpm for steel, fast as you can for Aluminium. Steve Blackmore ------- Date: Fri, 28 Jan 2005 05:57:28 -1000 (HST) From: benedict-listx~xxhawaii.rr.com Subject: Re: Re: Centre punching/Drilling [tagtools group] On Sat, 29 Jan 2005, Chris Ghent wrote: >> Robin wrote >> When running parts with lots of repetitive operations, being able to >> drop an operation or two has a big impact on total cycle time. >> I would go with a split-point stub/screw-machine drill. You may want to >> go with a TiN coating if you have enough holes to justify the cost >> (about 2x). >> I would use a peck cycle, or at least peck the first .01" of depth to >> start. The overall depth was not stated (as far as I can tell) but >> pecking is a good idea to extend cutter life. > thanks for your input, and everyone else also. A couple of followups, > and excuse me if I appear to overdetail this, I am working off a small > knowledge base here, compensating with enthusiasm. Sounds like a good compensation to me! I'd rather be enthusiastic than intimidated ANY day. > A screw-machine drill appears to just be shorter than a "normal" bit. So > there would be advantage in using one because it would not deflect as > much. But why would it need the peck thing first? Once it had started > the problem would be over. Or are you suggesting pecking with a larger > bit as a preliminary? The depth is 2mm, the material brass. If you're drilling through thin stuff, peck drilling doesn't buy you a whole lot. "Thin stuff" in this case means less than a drill diameter or so. (If you're drilling a 6mm hole in 2mm sheet, it's thin stuff. If you're drilling a 0.2mm hole in 2mm sheet, it's bar stock. ;) ) If you're drilling in anything over about 1.5 to 2 drill diameters, peck drilling helps clear chips. To play with this, take a big beefy drill bit, chuck it in a drill press, and just ram it down into some material as hard and as fast as you can. Don't retract to clear chips, just shove as hard as you can. After a while the drill press should start working pretty hard to keep the drill turning. At this point the flutes are clogged, and chances are there's no cutting fluid or coolant at the bottom of the hole. Retract the drill to clear chips and squirt some coolant in. Put the drill back in the hole and keep going. It should be easier going this time. Here's where peck drilling comes in. You can specify how far down to go for the initial peck, how far above the hole to retract, and how far to go for each incremental drilling operation. I know I'm on the paranoid side, but I tend to do 2x drill diameter for the initial peck and 1x drill diameter for each subsequent peck. This does a good job of clearing chips and letting coolant get back down inside a hole. One more extension to this is to peck with dwell. You can specify how long to sit at the bottom of the hole for each peck, in milliseconds, to allow the chip to thin out to nothing. This is a nicety for carbide drills since it reduces the risk of chipping the cutting edges of the drill. There should be a file in the Files area that's a primer on hand-coding G-code. It goes into peck drilling in more depth, as well as how to calculate dwell times. Tom P.S. Another alternative if you're doing through-holes is to "drill" your holes by plunging an end-mill into the material. If you're doing milling and drilling operations, and can arrange things so your mill is the same size as your holes, it means one fewer tool change and one fewer set of operations to go through. I've only had a couple of parts that have really been handy this way, but when it works it can be a real time saver. P.P.S. If you can stand using a smaller mill than the holes you're drilling, you can use G02 and G03 to make a circular pocket larger than your end mill. The surface finish won't always be nice, and a drill or reamer would definitely give a better hole, but that way you can do a bunch of different sized holes using a single mill. You have to balance time wasted running a mill around in little circles versus time wasted swapping tools. It's a trade-off. Tom ------- Date: Sat, 29 Jan 2005 04:32:57 -0000 From: "rpetrick2002" Subject: Re: Centre punching/Drilling --- In taigtoolsx~xxyahoogroups.com, Chris Ghent wrote: > I'm setting out to cut a large number of small identical parts from a > sheet. Each part needs two 1.3mm holes drilled. A 1.3 mm hole is fairly large for a small scale part. I regularly use a 1/32" 2-flute square end mill to 'drill' holes in 12 gage to 24 gage sheet brass, copper, and sterling. The end mill is rigid enough to plunge straight down through the material. But remember that the cut length is only three times the diameter, so for deeper holes you'll need a long fluted cutter. I've also wondered for quite a while about the problem you describe. I need to drill very small holes (#60 - #76) in various materials. The problem is that the small diameter drill bits 'dance' on the surface (until just before they snap!) unless you use a center punch. The question is how to get my Taig mill to perform this operation. My solution has been to hand punch the locations and use my drill press to drill the holes, but I'm looking for the high-tech and more productive CNC answer. Robert ------- Date: Fri, 28 Jan 2005 21:08:18 -0800 (GMT-08:00) From: Larry Richter Subject: Re: Re: Centre punching/Drilling Well, there is always a way, but sometimes the solution would astound the end buyer. Suppose you had the starter holes chemically or electro- chemically dimpled into the surface? A major pain, maybe, but how many ruined parts and broken drills would balance out on the money, at least until your new experience helped you find something better? And then there is the common autohammer center punch, a buck on sale from India, and probably less than a hundred for the absolute best on earth. Possibly this could be chucked up in the mill and brought down repeatedly and successfully to a punch let-off on the work. Or maybe a single stroke, teasing-control air hammer, instead of a self acting center punch. A tiny cutting laser is probably out. Maybe you could top the metal with a sacrificial sheet of something softer, that the bit could penetrate easily and accurately, but which would resist bit drift and be strippable after the holes are done. Or perhaps you could space the parts so they occur in conformance with a predrilled pattern in some common electronic board material, which you could use as a guide. Or, perhaps you could even prepare a piece of conventional tooling, a pierced plate, to guide just this one operation. Or something. Or perhaps the spindle could carry just one guide/support hole in a semi-fixed mount around along with the drill bit. Maybe you could chuck up one of those 400,000 rpm turbocarvers to center punch. They weigh about as much as half an Oreo and cut without appreciable pressure. There has to be something. ------- Date: Sat, 29 Jan 2005 10:54:28 -0000 From: "John Stevenson" Subject: Re: Centre punching/Drilling I do a lot of small hole drilling on CNC's, by small I mean down to 1.8mm and we just use a stub drill usually TiN coated and good quality Gurhing or similar with no problem. We peck at 1.5 times the drill diameter and flood cool, more to wash chips away. In reply to the question about really tiny holes and starting no one has mentioned NC spotting drills. These are short stub drill with different point angles especially made for doing start holes in work. You go round and spot with these then swap tools and drill. If you get the depth correct the dimple caused by these will act as a slight countersink or edge removal for the small hole, looks neat and saves deburring. ------- Date: Sat, 29 Jan 2005 12:15:50 -0000 From: "Robin S." Subject: Re: Centre punching/Drilling John, I agree with you about the spotting drill. I would hope it wouldn't be necessary with a 1.3mm stub drill, however. That extra operation could really kill productivity (especially since the Taig doesn't have an auto tool changer - at least it doesn't come with one stock). We specifically use 90º spotting drills at work because of the chamfer (or countersinking metric countersunk screws). You can almost certainly get 82º spotting drills for countersinking imperial countersunk screws. For the least amount of cutter wear, I believe a 118º spotting drill (or whatever angle your drill happens to be) would be best as the jobber drill will start the cut by cutting along its entire lip length. It will, however, give you a funny chamfer if you want it to create one at all. If you can get a spindle that goes fast enough, you don't actually need any special spotting. You can drill very small holes (like #60-#80) with a simple jobber-length drill and it won't wander. No spotting, punching or anything else. I used a precision drill press at a previous shop for this. I think it went faster than 30kRPM. Very nice. Regards, Robin ------- Date: Sat, 29 Jan 2005 13:54:29 -0000 From: "rpetrick2002" Subject: Re: Centre punching/Drilling Thanks for the info. I have been using my precision drill press for this work. It has a feather-touch feed rate and is controlled by a calibrated Mark II Eyeball, but I'm trying to at least get the pattern and layout work done by the CNC mill. The 90-degree spotting drill sounds promising. Spotting the holes and then changing bits is not too much of a problem, even though the Taig does not have a tool change feature. And even if I have to spot the holes with the Taig and remove the work and re-setup on the drill press, that would still be better than now. All the previous posts about tiny engraving bits got me thinking that maybe they would also work for this. Robert ------- Date: Sat, 29 Jan 2005 06:25:20 -0800 From: Mark Woloszyk Subject: Re: Re: Centre punching/Drilling I dont know if this will be accurate enough (or possible) for your work but I found it very convient when going from endmill to spotting drill to drill. http://www.industrialhobbies.com/howto/tips/Automaticpart1.htm http://www.industrialhobbies.com/howto/tips/Automaticpart2.htm http://www.industrialhobbies.com/howto/tips/Automaticpart3.htm ------- Date: Sat, 29 Jan 2005 17:14:12 -0000 From: "dkp_design" Subject: Re: Centre punching/Drilling In taigtoolsx~xxyahoogroups.com, "John Stevenson" wrote: >> Check out http://store.yahoo.com/drillcity/ I get all my drill's, from .004" to .250: from them. There 1/8" shank, and have a collar stop on them. They seem to last a really long time and don't seem to have any flex that I can notice. They have a really flat point, and drill into Alum nicely. << ------- Date: Tue, 1 Feb 2005 21:34:38 -0500 From: "rigrac" Subject: Re: How to Finish a Backplate [atlas_craftsman group] [NOTE TO FILE: This suggestion comes from a conversation on counter- boring, which can be a drilling operation, to set screw heads below the surface; while they were talking about holes for holding a chuck to a backplate, this tip can be used anywhere appropriate. Counter-bore drill bits are fairly expensive and this method provides an inexensive alternative.] You can drill hole to approximate depth from point of drill and then take the same drill to your bench grinder and make a "Flat Bottom" drill out of it and do the counterbore with it. Just look at the end of an Endmill and grind drillbit like endmill on the bottom. Drill must still have clearance on the flute as does a regular drill for it to work well. Hard to explain in print but I do it all the time for counterbores for Allen Head Capscrews. Ron ------- From: "n2562001" Date: Mon Apr 11, 2005 4:13 pm Subject: Re: Easiest way to line up a mill to drill small holes? Ron OConnor" [sherline group] wrote: > I want to replace existing cast in place boltheads on a plastic kit > with brass bolts. I am thinking of: > 1) using a laser center finder to line up with the bolthead. > 2) replacing the finder with a drill chuck. > 3) drilling a #73 hole. > 4) lastly using a 1/16" end mill to remove the existing bolthead. > 36 times on 4 pieces. Ron: To position the spindle in the center of the bolt head first turn the end of a rod the same diameter as the bolt head. You can then easily center the end of the rod over the bolt head with a good quality magnifier. Jerry Kieffer ------- Ron OConnor" Date: Mon Apr 11, 2005 7:27 pm Subject: Re: Easiest way to line up a mill to drill small holes? And I can hold the rod in the drill chuck so I don't have to change back and forth from the finder to the chuck. :) And I don't get to spend $50.00 on a laser center finder. :( Durn, you fellows that have been doing this for awhile are a clever lot! Thanks! Ron ------- steve boylan Date: Mon Apr 11, 2005 9:56 pm Subject: Re: Easiest way to line up a mill to drill small holes? Ron, Or, depending on just how accurate you want the center to be and if the plastic head is big enough, just grab the existing head in the drill chuck (wiggling it to get it close to center), clamp the part, release the chuck, insert drill, and drill it. That would not yield extreme accuracy, but might get the job done quickly. (If I wanted it accurate, I'd take Jerry's advice - and it wouldn't take much longer to do it his way.) Steve, the lazy ------- Andrew Werby" Date: Tue Apr 12, 2005 3:44 pm Subject: Re: Re: Re: Easiest way to line up a mill to drill small holes? [If you have a lathe, then you can turn a depression into the end of a rod which would just slip over one of those boltheads. With the rod in your chuck, it would be easy enough to see when you were right on it, then to substitute a drill for the rod.] Andrew Werby www.computersculpture.com ------- Jerry G" Date: Tue Apr 12, 2005 8:52 pm Subject: Re: Easiest way to line up a mill to drill small holes? Normally, the center to center of cast in boltheads are nominal dimensions, so, if you measure from one to another with a scale (6" rule). 1" will be one inch, etc. Your real problem is the initial pick up. My suggestion. Put a centerdrill in the drill chuck. Eyeball the position over the first bolthead. Center drill. Drill a small hole. Measure the distance from the hole to each of the flats. Adjust accordingly. Use an endmill to correct the location. Now, just crank off the nominal locations...Center drill and drill. Regards, Jerry G (Glickstein) ------- NOTE TO FILE: PREVENT TAILSTOCK CENTER SLIPPAGE (MORSE TAPER SLIPPAGE) I recall this topic has been dealt with somewhere else in these files but under what subject wording I forget. So here are a few tips. Morse tapers depend on a perfect friction fit. They should be clean and wiped free of oil before plugging them into the tailstock taper (or into the headstock for that matter). Morse tapers, internal or external, need to be free of raised burrs. Carefully remove any with a fine file or stone applied to the burr only. Small holes or scratches or depressions can be ignored. When a chuck is held on a Morse taper in the tailstock, the tool it is holding still (drill bit for example) may grab within the rotating work held on the headstock, and then spin. Not good as it can ruin the workpiece, damage the tailstock internal taper, and spoil your day. More positively stopping the male Morse taper from slipping/spinning in the tailstock might be accomplished in several ways. - Use a Morse taper with a flat tail that locks it from spinning. This option depends on your tailstock design as to whether there are provisions to lock such a tail, or whether you must add a wedge or setscrew to accomplish the locking. Note that all such locks depend on a rather fragile tailstock casting or sleeve, and breaking that would really ruin your day. - It seems more common in UK writings to help the taper hold by wrapping the dry male taper with one thin layer (no overlapping) of writing paper. Should not be necessary, but it is an option you might try. - Similarly, dry chalk may be applied to the tapers. Might help a bit. - You can leave the chuck key in the drill chuck and support its free end firmly on the lathe carriage. Or substitute a metal rod, plugged into the chuck keyhole, and similarly supported on the carriage. It might be wise to use adequate tape to make sure the chuck key or rod does not fall off. - Clamp locking pliers to the drill bit and firmly support the other end on the carriage. Or similarly use a lathe dog. Some of these ideas came from the Web, and some have been suggested by Roy Moungovan in his indispensible book "Shop Savvy". Buy it. Tons of excellent advice on many metalworking and woodworking topics. You will probably have to find a used version; try Web book search sites. ------- Date: Fri, 23 Dec 2005 22:04:12 -0500 From: Henry Boucher Subject: Long holes drilling New to metal turning, but I have a few years in music instruments making. Flutes and bagpipes makers use gun drills, one popular maker is http://www.danjon.com/quality.htm They even made special wood drills, with a cutting angle better for wood work. ------- Drilling hole in clock wheels arbor for new pivot. [sherline] Posted by: "raboomer" roger.alexanderx~xxcomcast.net Date: Wed Aug 2, 2006 9:44 pm (PDT) I'm having a problem finding the center of clock arbors when I try to drill them for re-pivoting. I either use a small drill chuck or three jaw chuck to hold one end; I support the end to be drilled with a steady rest. I put a small center drill in the drill chuck mounted in the tail stock. I then eye ball the positioning of the steady rest. About half of the time I'm off enough that I have to redrill for a larger pivot, then turn the pivot down. How do you pros do it? ------- Re: Drilling hole in clock wheels arbor for new pivot. Posted by: "Jerry G" chieftoolmakerx~xxearthlink.net Date: Thu Aug 3, 2006 3:26 am (PDT) Ask Jerry Kieffer... AFTER he answers you, I will give you my thoughts..... :) Jerry G (Glickstein) ------- Re: Drilling hole in clock wheels arbor for new pivot. Posted by: "n2562001" jlkiefferx~xxcharter.net Date: Thu Aug 3, 2006 9:20 am (PDT) Roger: Just to please my good buddy Jerry G I will answer first. I will assume that you are using the Sherline lathe with the drill chuck as it came from the factory. If so the alignment will probably be a few thousands off in any one direction. This may or may not be corrected by turning the chuck to change the point of impact. I have found the smallest center drill that can typically be used with a sherline lathe from the factory is a number one. Or in other words the smallest one (.046" Tip) that will not leave a little "tit" sticking up in the middle of the drilled center. If there is a little "Tit" sticking up in the middle, it will cause the drill to wander off center in most cases. I would suggest using a number one center drill as it is small enough for almost all clock work. If you wish to correct the alignment (really not needed for clock work) you can do it with the P/N 1202 Chuck centering attachment. The Sherline steady rest as it comes from the factory can be difficult to use with small clock arbors. I would suggest that you modify one end of each of the square brass support rods as follows. Install in a four jaw chuck or a slit sleeve in a three jaw chuck so they are centered for machining. Then machine a round angle similar to sharpening a pencil down to about a 1/8" flat stop on each one. In use this will allow you to work in tight areas as well as hold smaller diameter arbors. For an even better arrangement, small bearings can be installed on the end of each rod. To set up the steady rest, eyeballing the center position will not work. First measure the diameter of the arbor you are going to hold. Then locate the steady rest as close as possible to the chuck or collet you are using to drive the arbor. Next install (if long enough) the arbor or drill shank/pin gage of the same diameter as the arbor in the chuck/collet. Next position the bottom two support rods against the bottom of the arbor/drill shank/pin gage and lock into place. Next relocate the steady rest and setup the arbor in place to be drilled. When that is completed the upper support rod is lowered and locked into place. This should center your arbor for drilling. One additional note. All clock pivots should be installed over size and machined back down to proper size. This will be the only way to assure a straight, round, centered pivot unless you are really really lucky. Jerry Kieffer ------- Re: Drilling hole in clock wheels arbor for new pivot. Posted by: "Roger Alexander" roger.alexanderx~xxcomcast.net Date: Thu Aug 3, 2006 9:23 pm (PDT) Good Evening, Jerry, thanks for the input. I'll turn the tips of the brass rods tomorrow and use your suggestions on aligning them. I am using a Sherline lathe. Are there any photos posted showing the arms with bearings attached? Another question! I'm thinking of buying Sherline's collet adapter. Any suggestions on which collets are most useful with American mantel and shelf clocks? My guess is that whatever I buy it will be the wrong size. Thanks again for the suggestions, Roger ------- Re: Drilling hole in clock wheels arbor for new pivot. Posted by: "n2562001" jlkiefferx~xxcharter.net Date: Fri Aug 4, 2006 11:18 am (PDT) Roger: I don`t have any photo`s of a sherline steady rest bearing conversion. However it is as simple as machining a 3/32"-1/8" wide slot that straddles a bearing and dilling a hole to pin them in place. For holding stock down to .050" inch in diameter you can use SR2-5ZZ bearings. For smaller diameters use SF144ZZ bearings. Buying WW collets is kind of like buying drill bits. No matter how many you have you still never have the right ones. Most all clock work will fall in the range of #16 to #48 but there will always be an occasional need for others. You can always ask Sherline for a break on a reduced set or try your luck on E-Bay. There are several dealers who sell used collets but again it can be a crap shoot and time consuming even if you have return privlege. I would suggest the purchase of a 8MM adaptor if you plan to use brands other than Sherline. Jerry Kieffer ------- Re: Drilling hole in clock wheels arbor for new pivot. Posted by: "Willard E Wheaton Jr" wwheatonjrx~xxverizon.net Date: Sat Aug 5, 2006 7:38 pm (PDT) Roger: Jerry's technique will work, but there is another method used by clockmakers, which employs a graver (similar to a miniature woodworker's lathe tool). You chuck up the arbor as you presently are doing. Dial Indicate it to center in the steady rest, then with the graver supported on a Tee Rest (think wood turning) you can stick the point of the graver against the end of the arbor, and push it in, and towards the center. It will do what you're trying to do with the center drill, but will automatically find dead center. Now with the center found, you can use your drill in the tail stock chuck, or even better, put it in a pin vise, and slowly hand feed it into the arbor. If you use a dead center loosely inserted into the back of the pin vise, and keep moving the dead center gently toward the headstock (while maintaining a loose coupling between the rear of the pin vise and the point of the dead center, you can put the hole on dead center. Remember, the force for drilling is from your hand, not from the tailstock. Willard Wheaton ------- Re: Drilling hole in clock wheels arbor for new pivot. Posted by: "n2562001" jlkiefferx~xxcharter.net Date: Sun Aug 6, 2006 8:37 am (PDT) Willard: We each have our own methods and comfort zones however this is a method that I personally can not endorse for pivot work for the following reasons. This method is generally used by watchmakers who for whatever reason did not purchase a Jewelers lathe with a collet holding tailstock. You are correct that an accurate center can easily be cut with a very sharp graver in the hands of a skilled user. If you do not use a graver on a regular basis, then of course the center drill will do the same job with little or any skill. When drilling a short hole for installation of a pivot, it is highly desirable to have a straight round, centered non tapered hole for a solid strong friction fit of the pivot. Because the hole is short (three to four times pivot diameter) the drill must be held solidly in place and in alignment with the spindle to prevent taper. I don`t think I have ever seen a pin vise that actually held anything really straight, certainly not as straight as a tailstock and chuck/collet holder. When feeding a drill by hand it would take a very highly skilled person to drill a non taper short hole even with the aid of a tailstock center using a pin vise. When I give repivoting classes I normally have someone experienced in this method demonstrate it. The hole is then checked with a pin gage for side to side movement compared to one drilled with the tailstock using the same drill. The results of course have to be seen in person to be appreciated. If you have even the slightest taper in a pivot hole, friction fit pivots have a tendency to work themselves loose as they turn with a load on one side. If they come loose they can also come out and the works will free spin causing untold damage. (I have collected several Photo`s over the years.) If it is a very common kitchen/Mantel clock it's not that big of a deal since works are plentiful and cheap. However if it is a highly collectable Regulator or whatever you are in deep trouble. A tapered pivot hole produced by one`s self or a previous repair person can be corrected by boring with a micro boring bar using any of the typical Arbor/wheel holding methods. Jerry Kieffer ------- Re: Drilling hole in clock wheels arbor for new pivot. Posted by: "Roger Alexander" roger.alexanderx~xxcomcast.net Date: Sun Aug 6, 2006 5:03 pm (PDT) Willard & Jerry: Once the hole is in I have been using Loctite; I have also been told to use a very small of Tix solder. Is solder to be avoided? Roger ------- Re: Drilling hole in clock wheels arbor for new pivot. Posted by: "n2562001" jlkiefferx~xxcharter.net Date: Sun Aug 6, 2006 7:06 pm (PDT) Roger: If a pivot is rotated into position in a proper friction fitted hole, no other method of holding the pivot will be required or desired. If any other holding method is required the mechanical connection between the arbor and pivot is not proper. It is not practical nor desirable to use any type of soft solder anywhere near a clock or watch works, unless it was used by the original manufacturer such as a couple of french spring barrels. It is low-strength with a undesirable appearance and will almost always cause corrosion down the road no matter how well you clean it. Solder of any type is not desirable for Repivot work and will almost always end up as a poor joint without a lot of hassle. First as you heat an arbor with a blind hole and a pivot in it, the air will expand in the hole and prevent the solder from flowing into it. The hotter you heat it, the more it expands. If you doubt this just watch the pivot jump out of the hole as you heat it. You can cross drill a small hole at the bottom of the Arbor hole to allow solder to flow but this decreases stength and is highly undesirable especially near a pinion gear. Unfortunately this type of work is quite common in clock repair. Usually the pinion gear ends up full of solder and they try to remove it with a hack saw blade after they plug up their file. If you encounter this type of work solder can be removed by heating it up until it flows and hit it with a shot of compressed air. If you remove it from pinion gears check each leaf closely for damage and re-polish as needed. Jerry Kieffer ------- NOTE TO FILE: There was an excellent drilling discussion with subject "Drilling small holes with the lathe" in the taigtools group starting on Aug 28, 2006. While some tips relate to the Taig lathe, there are some generic ideas that can be adapted to any lathe. See the file here at Machining and Metalworking at Home called Taig Lathe Tips. ------- Drilling 0.15" and 0.25" dia holes in Brass on the lathe? [sherline] Posted by: "Chuck Johnston" crjx~xxfrii.com Date: Thu Sep 14, 2006 5:36 pm (PDT) Any tips other than "be careful" when drilling some holes in small brass parts on the lathe? I am getting back into Hon3 models instead of building bikes this year and have lost my touch. Just broke a bunch of small drill bits #76-80 and some others in that range.......checked on the web and noticed the talk about dubbing the cutting edge back. How is this done on small bits? I don't have any stones or anything small enough to get in and flatten it off. I am using the Adjustable Chuck in the tailstock and it is centered ok. Just klutzy I guess Center drilling the hole before starting... Cutting fluid? Or would I be better off with flat bits? I am using a high speed on the lathe and feeding slowly. This is better but still not fun yet. Any tips or tricks from the experts? Thanks Chuck Johnston ------- Re: Drilling 0.15" and 0.25" dia holes in Brass on the lathe? Posted by: "Jerry G" chieftoolmakerx~xxearthlink.net Date: Thu Sep 14, 2006 5:48 pm (PDT) Hi Chuck: Try "drilling" by hand (without power... "choke" up on your drill bits, but don't clamp on the flutes...) Or, as an alternate, put your drills in a small collet/chuck in the headstock, rev it up, and slowly feed the tailstock in... Snug up on the lock screw... Or, a make an adapter similar to a floating die stock holder so you can "feel" the resistance of the drill before it breaks... :) Jerry G (Glickstein) ------- Re: Drilling 0.15" and 0.25" dia holes in Brass on the lathe? Posted by: "Marcus" implmexx~xxaxionet.com Date: Thu Sep 14, 2006 7:44 pm (PDT) Hi Chuck: I've found the most reliable way to drill tiny holes is to use a procedure called "peck drilling". What it involves, is a quill stop that can be adjusted in very small increments, so the drill can be advanced into the work by progressively lowering the stop 0.001" or so at a time and then feeding the quill up to the stop, repeating ad nauseum until you're to depth. It sounds (and is) dreadfully tedious, but it is a very reliable way to avoid overloading tiny drills. Unfortunately, stock Sherline equipment does not permit you to do this conveniently...it can be done, but only if you're willing to do some mods to the machine. A second way is to use a sensitive drilling attachment...Sherline makes one for the mill, but there is nothing for the tailstock of the lathe. A way around this is to mount the work upright on the mill table, indicate the workpiece into center and then drill it with the sensitive drilling attachment...this is actually a superior method in many respects to tailstock drilling and was the method of choice for doing accurate holes at the toolroom where I used to work. (I do need to mention though, that the lathe we had was a piece of crap, so everyone stayed away from it as much as possible!!) A third way is, of course, to rig up a sensitive drilling setup for the lathe. This is pretty easy to do; all it takes is a pin vise with a smooth accurate shank, and a block with an accurate mating hole mounted on the carriage and centered perfectly on the spindle axis. With these tiny drills, you can easily hold the pin vise body between your fingers...there is almost no torque on the drill at all, and if you've made your setup with care, you can feel the cutting action of the drill quite well. A fourth method, is to use magnification to observe what the drill is doing, and peck feed in by dial reading with the tailstock quill. This method requires good concentration, but it works very well too. I've used all these methods extensively...my favourite is to mount the part vertically on the Bridgeport table and peck down with the quill. I use this for all really dastardly holes, even though I've got 2 CNC machining centers. I've found there's still nothing like the feel you can get with a quill, and a stop, and your finely tuned senses. HTH. Cheers Marcus ------- Re: Drilling 0.15" and 0.25" dia holes in Brass on the lathe? Posted by: "Jerry G" chieftoolmakerx~xxearthlink.net Date: Thu Sep 14, 2006 9:54 pm (PDT) Ooops! Did I forget to mention that I mounted the modified headstock on the 2000 mill? Sorry about that... JG Original Message --> From: Jerry G To: sherlinex~xxyahoogroups.com Sent: Friday, September 15, 2006 12:48 AM Hi Marcus, Group, I have just uploaded a photo in my Album "Golden Hands", that shows how I drilled some small holes in the Brass Discs that make up part of my Deadeye Drill Jigs , also pictured in the album. The discs are 1.000" diameter by .250" thick. I needed to make a pattern of holes in each one as follows. Three holes in a base circle of .075" equally spaced at 120 degrees. Those holes were # 77 (.018" diameter through the .250"). Three holes in a base circle of .0575" equally spaced at 120 degrees. Those holes were # 78 (.016" diameter through the .250"). I had a headstock that I had bought from Sherline that was modified. The bore was enlarged from the standard .405" to 9/16", which is the largest diameter possible without jeopardizing the bearings. I had needed the extra diameter to make some ship model masts that were bigger than .405"... As it turns out, I should have bored out the headstock myself. Why? because there were tool marks in the bore that indicated it was done in a hurry. Someday, I will "tickle it' and smooth out the finish. :) Anyway, I mounted the headstock on my 4400 lathe and put a 3/8" end mill holder on the spindle threads. I bored out the end mill holder for a .500" push fit for a sensitive drilling attachment I bought. On the 2000 mill, (for the extra Z height), I mounted the Rotary Table and made an aluminum nest for the brass discs. Since the nest was milled in, the concentricity was assured. In the photo, right above the Albrecht chuck, you can see the knurled ring of the SDA which is used to advance the drill. Works great! BTW, Chuck, you mentioned drill bits from # 76-80.... (.020" - .0135") Yet, your subject line says 0.15" and 0.25" holes..... Is that an error? Did you mean to write .015" and .025" holes? Jerry G (Glickstein) ------- Re: Drilling 0.15" and 0.25" dia holes in Brass on the lathe? Posted by: "KM6VV" KM6VVx~xxSBCglobal.net Date: Fri Sep 15, 2006 9:48 am (PDT) Thanks Jerry: It might help if I was looking in the right group... ;>) That's what happens after one has a birthday! I can see a few little holes in the center of the brass disks, how do the jigs register to the stock being drilled? How is the orientation of the holes controlled? It looks like the disk is pinned to the brass angle. I also see two thumbscrews, what are they used for? Perhaps you described them in detail 10 days ago. I couldn't relate them to the "deadeyes" on a ship. But it would be interesting to know how this jig functions, if one were to apply it to one's own work. Alan KM6VV ------- Re: Drilling 0.15" and 0.25" dia holes in Brass on the lathe? Posted by: "Jerry G" chieftoolmakerx~xxearthlink.net Date: Fri Sep 15, 2006 11:32 am (PDT) Well, I just had a birthday and I'm in the right group! :) Here is a brief description of the Deadeye Drill Jigs and how they work. There is a bottom plate that is 1.000" diameter by .250 Thick. The bottom plate for each of the two different size deadeyes and jigs has three holes bored in the periphery at 120 degrees. There is a top plate for each size of deadeye and jig. They are also 1.000" diameter by .250" thick. That carries the pattern of holes to be drilled and functions as a "guide" plate. Both plates have a .09375" diameter reamed hole to "Index" and control the rotation of the plates relative to the desired hole pattern. There is a "Tangent" Shot Pin Frame ( angle) that has two drill bushings pressed in after boring in location. Then there are a pair of Shot Pins. I have also just added an Ejection hole that is not shown on the photos. The Ejection hole is on the center of each bottom plate and allows the user to use the Ejection Pin (not made yet) to easily remove the drilled deadeye blanks....So, one takes a deadeye blank and puts it in the recess of the bottom plate. The depth of the recess provides for .005" clamping when the top plate is screwed to the bottom plate. First, the Shot pin is used to align the two plates (top and bottom) with the index hole. Then, the thumbscrews (made by pressing a commercial "cap" onto a Socket Head Allen Cap Screw) secure the two plates (and the deadeye blank) in position for drilling. Now, the "heart" of the Jig is the Shot Pin System. The shot pin frame is clamped to a drill press, mill, etc. It is placed so that the drill in the chuck/collet in the spindle is exactly centered over the first hole in the pattern in the top plate. With the Shot pin engaged in one of the periphery holes in the bottom plate. The hole is drilled. The Shot Pin is removed, the Drill Jig "stack" is rotated to the next position. The Shot Pin is then engaged into the second position of the bottom plate. This procedure is repeated for the third position. After the drilling is done, remove the thumbscrews, use the ejection pin to remove the drilled deadeye, and start over, and over until you exhause the supply of blanks..... :) It does not matter which position of the Shot Pin is used to start with, since the Jigs were made according to the Highest Traditions of the Jerry Glickstein School of Toolmaking. :) Is that clear enough? Regards, Jerry G (Glickstein) ------- Re: Drilling 0.15" and 0.25" dia holes in Brass on the lathe? Q on Posted by: "Jerry G" chieftoolmakerx~xxearthlink.net Date: Fri Sep 15, 2006 9:14 pm (PDT) > What is a 'commercial "cap" '? Are these common to make this kind of > thumbscrew? Where would you buy them? > Are shot pins just loose tapered pins? I understand the function, but > what's the execution? Hi Bill: The caps are molded from a plastic compound. They are made to fit standard socket head cap screws. You just press them on to get a "Thumbscrew". A vise or arbor press is best. The main thing is to start them straight. If you google in "Shear-Loc Thumbscrews", you will get there. I have no commercial connection...Just a happy customer. The shot pins are standard steel dowel pins used to keep the relationship between the drill jig "stack" and the frame constant, and accurate. This shot pin system is commonly used in precision indexing tables in industry, which was my first exposure to them. In my jig, they are not tapered at all. > I can't tell from your picture how you held the brass disk in the > Aluminum holder. Was it just a friction fit or was some other way used > to keep the brass from shifting? Hi Alan: The brass discs were held to 1.0000" +.0005" - .0000" The nest was milled to 1.0005" diameter. Thereby giving me a possible error of .00025" freedom. The method used to hold the brass discs was two Socket Head Allen Cap Screws, 4-40 by 1/2" long. The nest was tapped accordingly. Between the close diameter, and the index pin hole plus close diameters of the # 4 clearance hole, there was very little place for any movement and/or error. I don't take any chances with my designs... :) Regards, Jerry G (Glickstein) ------- NOTE TO FILE: There is a good example in the Boring file here as to how a difficult hole-making operation can use a combination of drilling and boring and reaming to achieve a relatively deep hole while using a small lathe. See "Drilling 3" deep?" starting Feb 4, 2008. ------- Center Drill Usage Chart/Spotting Drill -- Follow Up [sherline] Posted by: "semovente" gigitreoseix~xxrogers.com semovente Date: Fri Mar 14, 2008 3:27 pm ((PDT)) Sherliners:: Thought I would add to my original thread with some additional information I found on various websites. .vp >From answers.com: "Center drill bits are used in metalworking to provide a starting hole for a larger-sized drill bit or to make a conical indentation in the end of a workpiece in which to mount a lathe center. In either use, the name seems apt, as the drill is either establishing the center of a hole or making a conical hole for a lathe center. However, the true purpose of a center drill is the latter task, while the former task is best done with a spotting drill (as explained in detail below). Nevertheless, because of the frequent lumping together of both the terminology and the tool use, suppliers may call center drills combined-drill-and-countersinks in order to make unambiguously clear what product is being ordered. Use in making holes for lathe centers Centre drills are meant to create a conical hole for "between centers" manufacturing processes (typically lathe or cylindrical-grinder work). That is, they provide a location for a (live, dead, or driven) center to locate the part about an axis. A workpiece machined between centers can be safely removed from one process (perhaps turning in a lathe) and set up in a later process (perhaps a grinding operation) with what is often a negligible loss in the co-axiality of features. Use in spotting hole centers Traditional twist drill bits may tend to wander when started on an unprepared surface. Once a bit wanders off-course it is difficult to bring it back on center. A center drill bit frequently provides a reasonable starting point as it is short and therefore has a reduced tendency to wander when drilling is started. While the above is a common use of center drills, it is a technically-incorrect practice and should not be considered for production use. The correct tool to start a traditionally-drilled hole (a hole drilled by a high-speed steel (HSS) twist drill) is a spotting drill, or a spot drill, as they are referred to in the U.S. The included angle of the spotting drill should be the same or greater than the conventional drill bit so that the drill bit will then start without undue stress on the drill's corners-causing premature failure of the drill and a loss of hole quality. Most modern solid-carbide drills should not be used in conjunction with a spot drill or a center drill. They are specifically designed to "start" their own hole. Usually, spot drilling will cause premature failure of the carbide drill and a certain loss of hole quality. If it is deemed necessary to chamfer a hole with a spot or center drill when a carbide drill is used, it is best practice to do so after the hole is drilled. Centre drills wander as easily as anything else in hand-held power drills-for such operations, a centre punch should be used to spot the planned hole centre prior to drilling a pilot hole. That said, a centre drill works nearly as well as a spotting drill for most rigidly-clamped drilling operations, especially in softer metals such as aluminum and its alloys. The small starting tip has a tendency to break, and it is economical and practical to make the drill bit double ended." >From Littlemachineshop.com: "Combined drills and countersinks, commonly called center drills, are used to to produce a center hole on a workpiece for turning between centers. Center drills are also used to start drilled holes. Because they are very stiff they don't have a tendency to wander. Here are the sizes of center drills. Number Body Dia. Drill Dia. Length 1 1/8" 3/64" 1 1/4" 2 3/16" 5/64" 1 7/8" 3 1/4" 7/64" 2" 4 5/16" 1/8" 2 1/8" 5 7/16" 3/16" 2 3/4" Here is a little treatise written by J. W. Early about center drills: The center drill is only for putting a starting mark on the work piece so that your conventional drill will start easy without walking or grabbing. If your finish drill is going to be 1/4" then I would use a #4 center drill which has a 1/8" diameter of the drill point and a 5/16" diameter body. With a 1/4" hole in order to avoid a push up burr when finish drilling the center drill shoulder should enter the part until the outer diameter of the resulting chamfer is about .270 to .280 in diameter giving a nice burr free chamfer to the hole after finish drilling. When drilling a hole that is going to be tapped then your outer chamfer should be .030 greater than the nominal diameter of the thread in order that no starting burr will be present on the part surface to be filed down or hand deburred." ------- Re: Center Drill Usage Chart/Spotting Drill -- Follow Up Posted by: "William Cox" wtcox_listx~xxcomcast.net Date: Sat Mar 15, 2008 9:06 am ((PDT)) Given the included angles, I understand why a 120 degree spotting drill makes sense for a "standard" 118 degree drill, but why a 90 degree point? McMaster on spotting drills: "Drills with larger point angles (flatter points) work well for hard, tough materials; drills with smaller point angles (sharper points) are better for soft, nonferrous metals." But the only drills I know of with less than 90 degree included angle are (maybe) center drills. So where do you use 90 degree spotting drills? Would you use them for (e.g.) aluminum and brass, then use a 118 degree drill? bill ------- Re: Center Drill Usage Chart/Spotting Drill -- Follow Up Posted by: "Marcus" implmexx~xxaxionet.com Date: Sat Mar 15, 2008 9:39 am ((PDT)) Hi Bill: They're often used as chamfer cutters in CNC mills. That way they make a workable spotting drill and also a workable tool for deburring. Saves one station on the toolchanger for other things. Cheers Marcus ------- Re: Center Drill Usage Chart/Spotting Drill -- Follow Up Posted by: "Keith Green" ksggx~xxtelus.net dart70ca Date: Sun Mar 16, 2008 9:34 am ((PDT)) Personally, I use center-drills for spot-drilling in my CNC mill at work. Mine is a #40 milling taper machine of about 15 Hp and 10,000 rpm speed. I have tried spot-drills in the past and find that they chip much more easily than I'd like and after that they wander a little without much indication that they're damaged. That being said, they're better in our big mill (#50 taper) as it's more sturdy. I think mine tends to 'wiggle' a tiny bit more with spotting drills due to their broader tip. One of the big reasons that 90 deg (included) spot drills are used may be the fact that they make good chamfering tools and so can save at least one tool-change on production runs. I have used them for just this purpose myself. For my purposes, though, and the materials I tend to be drilling (hard, tough alloys), center-drills are more accurate and cheaper to buy. The drawbacks I have with them are 1) that the drill might tend to chatter a bit on entry and 2) the point on the drill lip that first contacts the edge of the work at the center-drilled hole tends to wear/chip faster than is normal with a spotting drill. Keith ------- Question for Jerry K - on Your Names Demo [sherline] Posted by: "montanaaardvark" boblombardix~xxcfl.rr.com Date: Sun Apr 27, 2008 7:08 pm ((PDT)) Jerry: You demonstrated turning down a small piece of 12L14 steel to .010 diameter and then drilling a hole down its middle. I know you made your drill bits, but could you give a quick summary of how you did that? I'm assuming you turned down some more steel to .008 or whatever the size was. Was it also 12L14, or (harden-able) drill rod? How do you cut the "D" profile and sharpen it? Do you heat treat it? Thanks, Bob Montana_Aardvark ------- Re: Question for Jerry K - on Your Names Demo Posted by: "n2562001" jlkiefferx~xxcharter.net Date: Sun Apr 27, 2008 8:58 pm ((PDT)) Bob: It was very nice to meet you and your wife at the show. I enjoyed our brief discussion. The spade drills used in the demo were between .005" and .006". They were ground from factory hardened drill blanks with a small diamond wheel in a Sherline Mill. The setup was as follows. First a Sherline indexer was mounted to a short piece of bed material that in turn was mounted to the mill bed. The Blank was held in the indexer with WW collets for accuracy. The flats were then ground with several light passes and by rotating 180 degrees. The "Z" axis remained lightly locked at all times to increase accuracy of the handwheel settings. When the flats were ground to size the indexer was rotated to the correct tip angle. In addition a shim was placed under one end of the bed stock to generate a slight additional angle for tip relief. The tip was then ground by moving the side of the diamond wheel across the tip. The rotation was into and away from the tip to prevent breakage. Of course this was done under a Spindle Head mounted Microscope so the drill looked like a fence post. Jerry Kieffer ------- Drilling straight holes [sherline] Posted by: "Alan Haisley" alanhyx~xxroadrunner.com Date: Mon Apr 28, 2008 4:11 pm ((PDT)) I have read and been told that, unlike drilling on a drill press or mill, if you tailstock drill the hole will seek and follow the axis of rotation of the part. In other words, you will get a straight hole. How true is this? I certainly understand the possibility of a drill wandering if used in a drill press or mill, even if it is brand new and held in a collet, since there will be some amount of variation in the flutes and in the cutting end no matter how well made; as well as some amount of run-out in even the best spindle and collet setup. What about lathe drilling though? Does the drill actually go straight or does it drift a bit and then correct back to the axis of rotation. Just what is the theory and practical experience here? Alan ------- Re: Drilling straight holes Posted by: "Marcus" marcusx~xximplant-mechanix.com Date: Mon Apr 28, 2008 6:52 pm ((PDT)) Hi Alan: The drill will not follow the axis of rotation automatically, and will, in fact, wander off axis as the hole deepens. The best way to get a decent hole with a drill, is to center drill in your normal manner, predrill undersize, bore the first two drill diameters to a snug fit on the body of the drill, then set up the drill accurately in the carriage and dial it in. The drill will guide itself on the bored hole and do a reasonable job. I recently made some titanium probes with 1/8" diameter holes 6" deep that way, and I got the bores close enough that a drill blank went freely down the hole and clocked in within 0.005" runout at the far end. I prebored to 4 diameters deep for that one, and used a brand new Guhring drill for each hole, re-chucking it several times as I got deeper into the hole. This job should have been done with a gundrill, but the customer had an emergency and the parts needed to be done on the weekend. Gundrilling is done the same way, but a bushing substitutes for the pre-bored end, and high pressure oil is fed down a hole in the drill to flush the chips. Gundrills can do some totally amazing holes...1/4" diameter 30" long in 20 minutes and straight within 0.002" or so. Cheers Marcus ------- Re: Drilling straight holes Posted by: "a3sigma" dcclark111x~xxcomcast.net Date: Tue Apr 29, 2008 3:24 am ((PDT)) Hi Alan, a few points: It's certainly possible to drill a bad hole with a lathe, or any other tool, for all of the reasons we've been discussing -- most of them having to do with the fact that nothing is perfectly well aligned, and nothing is perfectly rigid. In principal, it doesn't matter whether the tool or the work is rotating, what matters is the relative motion between them. A hole doesn't know if it's being bored by a tool in a boring head on a mill, or on the tool post of a lathe. I think that where the notion you've heard comes from is this: Say you have a stiff center drill in a tail stock that is slightly off center. It may act sort of like an end mill or boring tool. You'd get a start hole that is slightly oversize, but coaxial with the center of rotation of the head stock. If the tail stock is not very rigid, it may move to align itself with the hole, hence the center of rotation. Switch to a twist drill, and it will flex to try to follow the start hole, but it's still being stressed sideways and will not produce a straight hole. An ordinary twist drill in a off center tail stock chuck will just wander around the center of rotation until it gets a bite, and start in wherever that happens to be. As has been pointed out here, the only way to produce a really straight hole is with a boring tool, and even then things can go wrong. Tool flex is the biggest problem. The bottom line is that nothing is perfect -- not perfectly straight, nor rigid, nor perfectly aligned. And no material is perfectly isotropic nor homogeneous. A major part of the engineering art is to make a realistic assessment of your actual tolerance requirements and do what is needed to achieve them. Tolerance analysis is a whole 'nother book (or 3). Sadly, these books rarely see the light of day in engineering schools. Not to start another engineer-bashing thread, we're our own engineers and designers, here. And I've rarely seen a drawing for home shop machinists that has any tolerances indicated. Regards, DC ------- Re: Drilling straight holes Posted by: "Ian Newman" ian_newx~xxyahoo.com Date: Tue Apr 29, 2008 5:45 am ((PDT)) Hi Alan: There is a big difference between drilling a hole with a fixed drill and a rotating work piece and the other option of a rotating drill and a fixed work piece. If the work piece is fixed, the drill rotates on its own centreline and (assuming the cutting edges are symetrical) the cutting forces are always equal on each side of the drill. The drill will wander, of course, as we have all found through experience. Now consider the opposite situation of a fixed drill cutting a hole in a rotating work piece: If the drill starts to wander off the centre of rotation of the work, the side of the drill that has moved towards the centre of rotation will now cut on a smaller radius so it will experience less cutting force reaction than the side of the drill that has moved away from the centre and is now cutting on a larger radius. This means the forces on the drill are now unbalanced and will tend to push the drill back towards the centre of rotation. I have a neat little clip pinched off of youtube which demonstrates the effect - I'll try and find it and send it to you if you are interested. Ian ------- Re: Drilling straight holes Posted by: "Ian Newman" ian_newx~xxyahoo.com Date: Tue Apr 29, 2008 5:50 am ((PDT)) Hi. Follow up to my last post - I've just found the original reference to the youtube video that demonstrates the trick of rotating the work rather than the drill bit. When the drill starts to 'wander', most of the cutting force acts on the side of the drill doing most work, so the drill tends to push itself back to the centre. http://nl.youtube.com/watch?v=q6-4oyIoku4&NR=1 Ian ------- Best way to make holes in 6061 aluminum [taigtools] Posted by: "ein_hawk" jantelmax~xxyahoo.com Date: Thu May 22, 2008 2:49 am ((PDT)) Hi everyone, I have run into some trouble trying to make 0.205 inch diameter holes in 0.5 thick aluminum. I am trying to make a grid of holes, which I will eventually tap so that I can make a tool plate. I did not think this would be that hard but it is not going so well for me. I am using a .1875 inch, 2 flute, carbide end mill to make the holes. I just make the grid of holes in CAD and have my CAM software convert it to g-code. The code basically takes the end mill down 0.5 inches at 1 in/min and then widens the hole to 0.205 in. By the time I get to the 4th or 5th hole, the cutters on the end mill fill up with aluminum and the spindle motors stalls out (i.e. the end mill stops turning.) Obviously, I am not going about this correctly. Can someone please tell me what I should do to drill these holes without getting the end mill clogged up? I am sure I could play around with several different conditions and figure it out, but I am hoping someone with experience can point me in the right direction. Thanks Josh ------- Re: Best way to make holes in 6061 aluminum Posted by: "kd006" kd006x~xxyahoo.com Date: Thu May 22, 2008 3:57 am ((PDT)) Josh, I would start out with a drill not an endmill to make your holes. 0.205 is a odd number to me, is this for a 1/4-20 or metric thread? For a tool plate you really (IMO) don't need all that much fooling around, just drill the holes and then tap em, going at that with g-code to use a small cutter to plunge and then cut a diameter? You also didn't mention any lubrication, brush, mist or flood that could make a big difference. Might want to make a die block for tapping too, as it sounds like you're going to be tapping a bunch and that would get you started straight into the hole and avoid breaking off a tap in the 6061(T6?) Seems I recall beeswax or even plain old parifin like used for canning is a pretty good lube for tapping aluminum or brass. Kristin PS- I was reminded this morning to check me speed/feed rate too, there is an on line thing for that in an earlier post of mine I ------- Re: Best way to make holes in 6061 aluminum Posted by: "Ken Cline" clinex~xxfrii.com hfxlhfxl Date: Thu May 22, 2008 7:27 am ((PDT)) On 22 May 2008, at 4:57 AM, kd006 wrote: > I would start out with a drill not an endmill ... Using a drill should be quicker and may produce a hole that is rounder than circular interpolation, but drills have a tendency to wander when starting a hole, which not only displaces the hole but also cause the drill to bend and bore diagonally. I use a beefy spotting drill for starting holes (center drills are also used for this purpose). Also, I find that drills clog up easily if you just push them down into the aluminum without lubrication. > You also didn't mention any lubrication, brush, mist or flood that > could make a big difference. I machine 6000 and 7000 series aluminum very reliably with my Taig mill, using a small brush to apply cutting oil and compressed air for cooling and removing chips. When drilling, I run a chip clearing cycle that pulls the drill completely out of the material at frequent intervals allowing me to clean and lubricate the drill's tip. It may not be the fastest approach, but I raise the drill all the way out of the stock each time I break chips. Using an end mill to Machine pockets presents the challenge of trying to keep the pocket clear of swarf and lubricated at the same time. Flood cooling may be the best solution to this problem, but I get by using my compressed air and brush though it often means I have to pause the program at intervals to lubricate the operation. I have never tried to plunge an end mill to a depth of several times its diameter. When taking full width cuts I generally work at a depth equal to the end mill's radius, taking as many passes as necessary. > Might want to make a die block for tapping too Absolutely! > Seems I recall beeswax or even plain old > parifin like used for canning is a pretty good lube for tapping > aluminum or brass. I use tapping oil (Rapid Tap) for both tapping and cutting. Works great. ------- Re: Best way to make holes in 6061 aluminum Posted by: "Steve Blackmore" stevex~xxpilotltd.net Date: Thu May 22, 2008 8:38 am ((PDT)) On Thu, 22 May 2008, Greg McFadden wrote: >I tend to helically interpolate holes like that. It seems to give me the >best results unless I ream them. So do I, but not for holes I'm going to tap - I simply drill them ;) Steve Blackmore ------- Re: Best way to make holes in 6061 aluminum Posted by: "Chris Manning" kenricx~xxlozengy.net Date: Thu May 22, 2008 6:37 pm ((PDT)) Jeff Demand wrote: >While I prefer pretty solutions there are a lot of hammers in my > collection which sure are fun to use. Still waiting for good > justification to buy a 20+ ton hydraulic one :-) Brute force and ignorance. The two most important tools in your shop. Chris ------- Re: Question from a novice [sherline] Posted by: "Jeff Demand" jdemandx~xxgmavt.net Date: Sat Aug 16, 2008 11:41 am ((PDT)) A couple of thoughts from a jeweller who does some machining and drills most small holes with a hand held flex shaft. I never centre punch, I'll cut the mark with a very small ball burr or an engraver. A punched mark work hardens the metal, the most right where you want the hole to be. Nothing like starting a hole on a hard spot surrounded by softer metal The other trick is NOT to chuck the drill too tight, if it jams I'd much rather have it spin in the chuck than break. Actually I normally use a cheap collet holder which is guaranteed to slip, good for hand holding but probably a real pain to set up on a mill. Concentricity totally lost but the again I am not that concentric :-). Jeff Demand Designs Analog/Digital Modelling & Goldsmithing http://www.gmavt.net/~jdemand ------- Drilling Phosphor Bronze [MyMyford] Posted by: "alan4227" a.j.moorex~xxbtinternet.com Date: Tue Oct 7, 2008 10:57 am ((PDT)) Help! Can anyone give me some expert advice? I am making a Hemingway kit - the machinist's hammer - as a gentle way of practising some of the basic skills before trying more ambitious projects. This hammer has a phosphor bronze head 1in diameter which needs to be cross-drilled 7/16in. I am trying to drill it in the lathe, starting with a 3/16in pilot drill, using white spirit as a cutting fluid (I don't have anything else at the moment). So far I have got maybe 3/8in through, withdrawing frequently to clear the chips and dribble on more white spirit, but the drill has seized twice and spun in the chuck. I have managed to free it with copious amounts of WD40 and rocking the chuck backwards and forwards, but I am terrified that if it seizes when I'm a lot further in I will never get it out. I have taken the advice from Sparey, Wright et al to stone off the tips of the drill to give zero rake, but I still have the problem. Can anyone suggest what I should do now? Many thanks, Alan ------- Re: Drilling Phosphor Bronze Posted by: "durnfjmx~xxaol.com" durnfjmx~xxaol.com Date: Tue Oct 7, 2008 12:37 pm ((PDT)) Hi Alan. my thoughts, The problem is that the PB grabs the drill, and pulls it into the cut. Tighten up the drill in the chuck as much as you dare (clean the drill and chuck jaws properly first), make sure the chuck is well "stuck" into the taper (clean the taper and socket properly, and tap in firmly with a soft hammer), assuming that you are drilling from the tailstock, nip up the tailstock feed until it is noticeably difficult to advance, then advance the drill slowly but positively into the workpiece, withdrawing it occasionally to clear the swarf. It's much easier to do than explain! You have probably done the right thing by trying to alter the drill geometry, but I have found this to be less important than a rigid and very "stiff" setup. Cutting fluids such as Rocol RTD types may help, but you really shouldn't need a cutting fluid for PB. I'm not sure that white spirit is any practical use. (WD40, ???? anyone else have opinions on this stuff????) My opinions only - works for me - but I'm sure others will have their own suggestions, and disagree with mine... :-) Take care, and be safe, MikeD ------- Re: Drilling Phosphor Bronze Posted by: "Scott A Stephens" sstephenssprint020x~xxearthlink.net Date: Tue Oct 7, 2008 2:23 pm ((PDT)) Without knowing more details of your setup, is it possible to hold the drill in a collet? Rather then a drill chuck? The other idea would be to step drill the hole. Also what is the speed you are using??? Feed I assume is by hand. ------- Re: Drilling Phosphor Bronze Posted by: "Just A Sec 1010" justasec1010x~xxyahoo.com.au Date: Tue Oct 7, 2008 3:49 pm ((PDT)) Hi. I was taught for non ferrous metals to take the edge off new drill bits to stop the grabbing. Hope this might help. Scott Simmonds ------- Re: Drilling Phosphor Bronze Posted by: "tr0up" a.troupx~xxemail.com tr0up Date: Tue Oct 7, 2008 7:45 pm ((PDT)) I disagree with the notion that changes to the geometry are unlikely to be a major factor - I note that you have stoned the 'tips' of the drill, but this advice is often misunderstood and consequently misapplied. Apologies to anyone who finds the following detailed explanation demeaning: because (to my mind) the conventional wisdom on this topic is so confusing, I've purposely tried to eliminate any ambiguity. This is mainly for the sake of whoever might come across it at some future date, who might have little formal engineering knowledge. To modify a drill to prevent grabbing in copper or lead alloys requires a small stone (ideally of triangular cross section, with one long corner rounded off, which can be done with an angle grinder or a grinding wheel). Another way, particularly for smaller drills, is to use one of the small diamond hones of a "D" cross section sold for sharpening small fish hooks. The long axis of this stone should be presented parallel with the long axis of the drill. The stone is introduced into a flute (one of the two helical recesses) so the rounded corner is nearest the central axis of the drill. The stone is then stroked, like a file, ie along its long axis, taking material off the 'active' face of the flute where it meets the straight cutting edge. The result, in lathe terms, is to reduce the 'top rake' to zero, although in your case you may even need to go to negative rake, as grabbing seems to be pronounced. If you have done this correctly, there would be flat area in these two zones, as long as the cutting edge, whose width is at least one-eighth the diameter of the drill. This caveat is important, and often why this modification fails to deliver the desired result: if much less, much of the chip will impinge on the raked area behind the flattened land, dragging the drill deeper into the job and causing the jam-up. Three other things: 1) Ideally there should be no 'slack motion' in the feed OR ROTATION of the drill. The reason is that if there is, any 'self-feeding' tendency by the drill will produce a runaway infeed, and the jamming effect you are experiencing. Rotational slack translates into axial free play, because the feed mechanism is a helical thread. Another poster hinted at this when he mentioned tightening up the feed, but omitted to explain how this is done, no easy matter for a tailstock. Here are a few suggestions: a) Check the barrel for rotational free play. If there is more than a few 'thou', you may have to remake the key (which is removed to the inside of the bore after removing the barrel) or (to get you out of this present situation) contrive a temporary shim from aluminium foil, brass shimstock, a piece of aluminium soft-drink can, even paper, or whatever you have of the right thickness. Apply this to one side of the key, perhaps using superglue (which turns paper into something reasonably durable). b) You don't say which lathe you have, so I'll assume an ML7. If there is much wear in the female thread of the handwheel and/or the mating male thread on the end of the barrel, you could try painting a stripe or three of some sort of (thinnish) resin along the latter, letting it set up hard before trying, and repeating if necessary until the fit is snug. This would need to be repeated occasionally, but would wear away preferentially on the thrust side, so might settle down after two or three iterations. This would only be necessary if your lathe was particularly worn in this area, but what is more likely to be worn (and easier to fix) is the flat key which engages edgewise with the annular recess inboard of the handwheel, taking the thrust. If there is play here, the key should be remade in thicker material, but given that you are just starting out, you may be able to kludge a temporary fix to get you out of your spot, once again using superglue and shim. There's another ad-hoc way to address both causes of endplay: you can improvise and bolt a 'tuning fork' style preventer to the carriage, which straddles the chuck and holds it back by engaging with the front face. When the drill is about to enter the hole, wind the carriage to the right so the preventer engages with the chuck, and apply a judicious amount of carriage lock (the bolt at the right rear of the carriage wings) so that a bit of extra effort is necessary to feed the drill forward. 2) The pilot hole should ideally be only as big as the solid area in the middle of the final size drill (the 'web'). Bigger pilot holes invite grabbing, and (in large sizes) don't provide enough thrust force to reliably ensure the Morse taper will not slip. 3) I mentioned ambiguity when advice is given about 'stoning the tips' of drills. This arises partly because of the unfortunate use of the term "tips", which suggests the junction of three faces. In fact the cutting edges of a drill, like any edge, are at the junction of two faces. However there are two pairs: the straight pair running outwards from the point towards what I would call the 'tips', and the helical pair running back from there. The latter are like the cutting edges of a hand reamer, but in theory (in a drill) should not have to do any cutting. In practice, however, drills wear progressively from the front end back. Consequently these edges do have to do a bit of cutting, just to make the hole big enough so they don't themselves jam in the hole. If this latter pair of edges are either 'modified' by mistake, or excessively worn, a drill may jam in ANY material to the point it becomes virtually a fixture. The same goes for the 'tips' proper: these should be sharp, or jamming is likely* *unless you are drilling really tough material, like tool steel, and are prepared to go to considerable effort of stoning them to a radius, in which case the third edge leaving the tip (ie neither of the cutting edges already discussed) must be carefully stoned to an even larger radius to provide 'relief'. Even in this case, the tips will be 'sharp', ie capable of shaving a thumbnail, if presented from the same direction as where the tips will 'see' material coming towards them from). One last thing (apologies for being so long winded, and I may be completely off beam in your specific case, as you've said nothing about your gear): cheap (eg Chinese) drill chucks are a waste of time: any savings vs the expense of a decent chuck will be swallowed up in damage to the shanks of your drills, which incidentally makes them unable to be replaced in their holders, and obscures the size stamped on the side. A Chinese ER collet MT2 set would possibly be quite a good compromise - they are affordable (exceptionally so, by collet standards), grip well, and the drill can be 'buried' in the hollow shank so only enough protrudes for the job in question. However if the other problems are not eliminated, the drill may still grab, in which case the collet chuck will likely spin in the tailstock barrel (the Morse taper may not be an exact match) and do damage to the lathe. ------- Re: Drilling Phosphor Bronze Posted by: "tr0up" a.troupx~xxemail.com tr0up Date: Wed Oct 8, 2008 12:13 am ((PDT)) > Tighten up the drill in the chuck as much as you dare (clean the > drill and chuck jaws properly first Just one late thought to add to this good advice: when using a key chuck, the best grip is achieved by going round the three key holes in turn, snugging up a bit more in each one. With an inferior chuck, you may find it difficult to loosen the shank for removal, having done this, but usually one of the holes will work for this purpose when the others don't. ------- Drilling Phosphor Bronze Posted by: "c j.s" callinicus1953x~xxyahoo.co.uk Date: Wed Oct 8, 2008 8:55 am ((PDT)) Hi Alan, Just a few thoiughts on your problem: 1. What speed are you using to drill your 3/16" hole? Something in the order of 100 feet per min for bronze means about 2000 RPM and about 900 RPM for the 7/16" drill 2 Have you tried an ordinary, unmodified, drill to see if it works any better? I keep a box of metric drills just for brass etc with blunted edges, but usually don't bother to use them. Ordinary drills usually work, just be careful and slow when reaching the breakout point. C.J.S. ------- Re: Drilling Phosphor Bronze Posted by: "alan4227" a.j.moorex~xxbtinternet.com Date: Wed Oct 8, 2008 10:09 am ((PDT)) I think it's time for me to 'fess up', as the Americans say. I don't currently have a 4 jaw chuck or a faceplate for my 254 (they are on order from Myford). I do, however, have an ancient vertical slide. My cunning plan was to clamp the hammer head to the slide and use the 3 jaw chuck as a drill chuck to make the cross-hole. I seem to have proved that lathe chucks do not hold 3/16in drills very tightly. Anyway, today's post has delivered a large parcel from Myford, so hopefully that will contain my faceplate and I'll be able to try again with the drill in the tailstock and see how I get on. I do have a diamond D section sharpener and that's what I was using to take the edge off my drill (freshly reground a few days ago), but it sounds as though I didn't take nearly enough off. So I will file some more. It also sounds as though I was not using enough rpm for a 3/16in pilot drill. I was on about 500rpm instead of 2000. I will pluck up my courage and move the belt to the big pulley. Many thanks for all the advice. This group has turned up trumps again! Regards, Alan ------- Re: Drilling Phosphor Bronze Posted by: "tr0up" a.troupx~xxemail.com Date: Wed Oct 8, 2008 12:33 pm ((PDT)) Alan, two observations: 1) You're right: lathe chucks don't make superb drill chucks (although if in decent condition they will do OK , and their grip can be improved by rubbing chalk on the grip faces before inserting the drill) For the future, do bear in mind that a drill chuck can be substituted for the lathe chuck by plugging it into the headstock taper. In the 254 I imagine you will need a reducing adapter. Drilling from the headstock is a valid technique, and probably preferable for really big holes as the severe load on the tailstock keyway and key is avoided; in grabby materials (the worst being pure copper and pure lead) I would however tend to engage the half nuts and feed the carriage using the leadscrew handwheel, rather than using the carriage (rack and pinion) handwheel. If the vertical slide is flimsy and the material being drilled is tough, you can even advance the (empty) tailstock barrel against the rear of the slide to provide backup support. I would NOT however recommend drilling this way round until you've fixed the grabbing problem, as spinning a chuck in the headstock taper is even more detrimental to the 'fabric' of the lathe than doing so in the tailstock. This is actually one point in favour of using a lathe chuck! 2) If the 7/16" drill is a 'regrind', and you continue to have problems, it may be that the two spiral cutting (or rather scraping) edges running towards the tail end of the drill are rounded over at and near the front corners. If a drill has been well used (particularly in abrasive materials) these edges will suffer, and regrinding does nothing to alleviate this, unless the drill is shortened considerably. ------- Re: Drilling Phosphor Bronze Posted by: "DA. Forsyth" notLeftBehindx~xxiwr.ru.ac.za Date: Wed Oct 8, 2008 11:45 pm ((PDT)) Wrap a single layer of laser printer paper around the drill. This incites HUGE friction between the bit and the jaws. I have never had anything slip with paper between the clamping surfaces. I use quality paper, fresh piece every time, clean all surfaces so you don't get swarf in between. David http://iwr.ru.ac.za/~iwdf/ ------- Fantastic info resource for home shop metalwork [MyMyford] Posted by: "tr0up" a.troupx~xxemail.com Date: Wed Nov 5, 2008 7:29 pm ((PST)) http://www.homemetalshopclub.org/news/article_index.htm I came across this quite by accident. It's amazing how much good stuff one can stumble across... Best I've seen -- check out the tip for maintaining position over a hole when the need arises to crank the head up or down on a round- column mill-drill: http://www.homemetalshopclub.org/news/aug02/aug02.html#maintaining Another which caught my eye was something I have also done, either for using drills whose taper shank is larger than the tailstock will accept, or when the taper is correct, as a precaution, when I'm concerned that the torque (especially if the drill grabs on breaking through) might spin the drill shank in the barrel (NOT recommended): http://www.homemetalshopclub.org/news/oct04/oct04.html#taper I'm going to take a break from regular visits to this and other metalworking sites for a while -- getting a bit behind on a few projects ... Hasta luego, todos mis amigos ! ------- steel router insert [shopbuilttools] Posted by: "Terry Ney" tney88x~xxyahoo.com Date: Fri Jan 16, 2009 4:26 pm ((PST)) Has anybody come across a source for a steel router insert plate (for table mounting a router)? I splurged and bought a nice cast iron router table wing for my Unisaw, but all the insert plates I find are either plastic or aluminum. I would like a ferrous metal plate so I can use my magnetic featherboards and hold-downs. I know I could just buy a remnant of 1/4" plate steel, and make it myself, but I'm really not set up to make a nice center hole of the diameter needed, I'd have to take it to a machine shop that has a milling machine. Any suggestions? Terry Ney ------- Re: steel router insert Posted by: "thesawyermantogo" bobo81341x~xxyahoo.com Date: Fri Jan 16, 2009 6:08 pm ((PST)) Terry: You could use a hole saw to cut a hole in the 1/4" plate; you would need a drill press. Then you could drill and tap 4 holes around the insert hole and place flat washers on the bolts for your inserts to set on. The inserts could be made of 1/4" hard board. Bobo ------- Re: steel router insert Posted by: "kendall bonner" merc2dogsx~xxyahoo.com Date: Fri Jan 16, 2009 10:27 pm ((PST)) He may still need to relieve the plate under the hole so the router isn't too badly limited in depth of cut, but you -can- do that with the router and a carbide bit in steel or hss in aluminum. The hole saw and drill press does work great. Set it to the lowest speed you have, use a good bi-metal saw, place work on a scrap of plywood and clamp it down. Then hook a bungie to the down feed to keep pressure on and go do something else for a bit. You'll hear when it starts to load up so just walk back and lift the bit a little, maybe dribble some soap into the cut and let it go again. I've cut 4" holes through 2" plate that way, just set up a little dribble can and go do something else. Ken ------- Anyone have a better way to do this? [atlas_craftsman] Posted by: "indianfourrider" indianfourriderx~xxyahoo.com Date: Thu Jan 29, 2009 7:48 am ((PST)) Friends, I want to pick the collective brain again. I am hoping to make small parabolic reflectors for the woefully inadequate taillights on late-model Indians. I bought a bunch of 4" dia. .75" thick 6061 aluminum slugs really cheap from a well-known auction site. Really cheap. The finished reflector will be 2.75" dia. I have cut one 2.857" disc with a bi-metal holesaw mounted in the tailstock of my 12x36. The results are very nice but it took almost 40 minutes! I could only cut about 1/4 turn of the handwheel then I had to clean the mud out of the teeth in the holesaw. I was cutting at 266 rpm and using CRC spray cutting fluid. The lathe is the only real machine tool I have. I do have an early 70's vintage Tiawanese drillpress with sloppy bearings. Am I being silly by not just reducing the excess to swarf? I haven't come up with a use for the resulting ring(s) or I wouldn't be asking the question! A picture of the setup and results is in my "Projects" album in the Photos section. Thanks in advance, Jim Walther ------- Re: Anyone have a better way to do this? Posted by: "Russ Kepler" russx~xxkepler-eng.com Date: Thu Jan 29, 2009 8:11 am ((PST)) If you don't have any use for the rings then it's silly to try and keep them. But I do it too. You could cut the center out a lot faster using a trepanning tool - it's a single point tool that feeds in from the front so it's a lot like a parting tool. The problem is cost - these tools have to be curved to about the same radius as the cut for clearance so you'll put a lot of cash into just a few tools. How were you planning on cutting the parabolic? ------- Re: Anyone have a better way to do this? Posted by: "Robert Silas" robert.silasx~xxvideotron.ca Date: Thu Jan 29, 2009 8:18 am ((PST)) James: Which one do you need?? the ring or the plug?? I cut deep hole in cast iron with hole saw of carbide tips. Hole saws, I found, always wobble and they increase the cut in diameter and create a lot of heat. I welded the shaft to the hole saw, then, held the saw part in the lathe and turned the shaft to be centric with the saw. I had no more problem. Of course the carbide tips are much wider than the teeth welded to, so more clearance left for cooling. Robert ------- Re: Anyone have a better way to do this? Posted by: "Russ Kepler" russx~xxkepler-eng.com Date: Thu Jan 29, 2009 9:12 am ((PST)) On Thursday 29 January 2009 Wayne wrote: > Why would it need to be a curved tool? why not grind a triangular or > parabolic cutter? to clear the curved part of the turned part? You can get away with anything that will give you enough clearance on the inside of the cut, but the face width goes up pretty quickly. Most of the trepanning tools that cut to any reasonable depth end up with a curve to provide clearance and enough height to support the cutting edge of the tool. For a pretty shallow cut you don't need to back the tool with much so it can look like a grooving tool. There's some discussion here: http://bbs.homeshopmachinist.net/showthread.php?t=27444 [In a later message Russ continued:] I don't think I was clear on this. If you make a tool to cut in on the face of the work you need to support the cutting edge. If the inside edge of the tool is not curved to match the cut radius then the width of the tool will have to be increased to get enough meat to support the cutting edge, this because the outside of the tool has to be ground for clearance. All in all it's just easiest to make the tool follow the radius of the cut with enough clearance inside and out to cut a number of radii. (If you want to see the extreme end of this sort of tool look for bowl cutters, the kind that take a chunk out of a log. The cutters look like a 1/4 section of a bowl with a carbide cutting edge and cut a "bowl" out of a log in just a few seconds.) ------- Need advice for drilling hardened stainless steel [sherline] Posted by: "Alan Haisley" alanhyx~xxroadrunner.com Date: Tue Mar 24, 2009 9:27 pm ((PDT)) Message #23324 started a short thread on drilling through hardened steel caliper jaws to make a DRO. My situation is similar but not identical. I am trying to rebuild a "dog dethatcher" that my son got on a trip to Eastern Europe. The blades have all come loose and so I thought, if I could drill a hole in each of them I could pin them in a 1/2" bar. These are little claw like shapes and I'm pretty sure they are hardened stainless. The material is about .030" thick. A HSS center drill made a small dimple with a lot of pressure but a 1/16" HSS drill bit did nothing. I'm thinking that I should buy a carbide center drill and a couple of 1/16" carbide drill bits. If I do, what kind of spindle speed should I be looking at to successfully drill through this kind of material? Although Jerry G suggested diamond bits in the original thread, I feel that the carbide bits will be more useful to me long term and would rather use them. Of course if carbide just won't hack it at all, other suggestions would help. In any event, I really need some idea just how fast to run the spindle for this. Alan ------- Re: Need advice for drilling hardened stainless steel Posted by: "Marcus" marcusx~xximplant-mechanix.com Date: Wed Mar 25, 2009 11:40 am ((PDT)) chieftoolmaker wrote: > P.S. Have you given a blade a file test for hardness? < Alan Haisley wrote: > No, but a brand new HSS drill bit just spins. I'm confident that whatever this stuff is I'm not going to be able to touch it with a file. I thought about tempering them, but once again, I need to avoid any uncorrectable situation because of lack of pieces to try things on. Alan < Hi Alan: I've been following this thread and thought I'd chime in. First, trying to grind these holes is a non-starter...it is so unlikely to work that I wouldn't even try. The reason is that the surface speed of the abrasive grains at the center of the tip is close to zero, so your chances of forcing them into and through your workpiece is very small. You'd have to angle the tip of a ball ended abrasive point into the work and then upright it once you broke through. That means freehanding it with a dental drill or some other hand held super high speed tool. I see two realistic options; one is with a carbide drill and a fixture to hold the parts in proper alignment, the second is to sinker EDM the holes or have it done by an outside vendor. You state that you cannot risk failure of even a single part since they're irreplaceable...that means a sinker if the parts are hardened and the consequence of failure is truly as you imply. The reason I say this, is that you have a web of only 0.03125" per side, once you drill a 1/16" hole into a 1/8" wide strip. You risk cracking one or both webs with a drill upon breakthrough, if the parts are anything harder than about 45 Rockwell. If you can accept some risk of failure, the carbide drill option becomes more viable. There are two secrets to success: 1) your part fixture must be able to hold the part very securely and support it perfectly from underneath so you're not flexing the part as you apply pressure to the drill and so it can't snatch the part on breakthrough. 2) Your drill must be stub length or shorter...ideally as short as you can make it and still get through the part. This means cutting off and ACCURATELY repointing a carbide drill, then running it in a watchmaker's collet so it's very concentric to the spindle. The setup needs to be as rigid as possible; a 5400 mill is preferable to a 2000 for this application, and no riser block on the headstock is also desirable. Your drill needs to be kept in perfect condition, and a microscope is useful (Jerry K would probably say essential) to watch what's going on in the drilling and to monitor tool condition too. Center drilling is a problem, this is why the shortest drill possible is so useful...it eliminates that step. Oh yeah...before I forget, circuit board drills are NOT a good choice for this; their flutes are too deep, so they're not very rigid against flexing, and carbide doesn't flex very much before breaking. I've had best success drilling hardened stainless over 50 Rockwell with Rapidtap as a lubricant, but you MUST then keep the drill perfectly sharp, or the presence of the lubricant will lower the coefficient of friction to the point that the drill won't bite, and you'll break it by applying too much pressure to it. I've drilled holes in hardened 420M stainless up to 10 diameters deep this way before I got my sinker, so I know it works, but you do have to pay attention to the details. Good luck with it. Cheers Marcus ------- Re: Need advice for drilling hardened stainless steel Posted by: "Alan Haisley" alanhyx~xxroadrunner.com Date: Wed Mar 25, 2009 4:02 pm ((PDT)) Marcus and others, I have added a picture called "Drilling Fixture" to the Alan Haisley's stuff folder. It should provide a better idea of what I am doing here and what I have done so far. I suspected the situation that you point out with a grinding attempt, Marcus, and that's why I have been leaning toward carbide drills. As you can see, I think that I have come up with a holding fixture that should not only work but will index each of the blades to be drilled so that I end up with uniformly placed holes - assuming that I can make the holes in the first place. If I find 1/16" carbide drills, should I run them wide open or slowed down? I assume that too slow will be a problem but just what kind of speed range am I looking at here? Alan ------- Re: Need advice for drilling hardened stainless steel Posted by: "n2562001" jlkiefferx~xxcharter.net Date: Wed Mar 25, 2009 4:43 pm ((PDT)) Alan: I would agree with what Marcus has suggested if you wish to drill the holes. If you only had one or two I could suggest a simple method of creating the hole but it sounds like you have several to do. If I were doing this and it was Ok to move the pin hole to the end of the piece I would do it as follows. I would cut a slot in the end of the piece about .062" deep and about .062 wide with a Dremel and a thin cutoff wheel. If the slots would need to be in the same place on each blade they could be stacked and all cut at the same time. Once cut the slot could then be pinned to whatever you are pinning it to. Jerry Kieffer ------- Re: Need advice for drilling hardened stainless steel Posted by: "chieftoolmaker" chieftoolmakerx~xxearthlink.net Date: Thu Mar 26, 2009 12:28 am ((PDT)) Marcus, A quickie..... I would NEVER try to plunge grind a mounted stone/point without relieving the end to take those abrasive grains at the center out of play.... And the parts in question are only .030" thick. Later, Cheers, Jerry G (Glickstein) ------- Re: Need advice for drilling hardened stainless steel Posted by: "Ron Ginger" rongingerx~xxroadrunner.com Date: Thu Mar 26, 2009 5:09 am ((PDT)) > My situation is similar but not identical. I am trying to rebuild a "dog dethatcher" that my son got on a trip to Eastern Europe. The blades have all come loose and so I thought, if I could drill a hole in each of them I could pin them in a 1/2" bar. These are little claw like shapes and I'm pretty sure they are hardened stainless. The material is about .030" thick. Drilling and pinning sounds like the wrong approach. If the parts are that small, a drill will seriously weaken the part. It's unlikely you can drive a pin in and make a really tight joint. I have a vision here of some of the things Ive seen nailed together where a bunch of nails get driven into a block and just split it all apart. How were the pins held in when it was built? If it was a simple press fit, maybe just replacing them with some epoxy or a Loctite product will fix it. If the original design did not use drilled holes and pins, I would not think a repair of drilled holes and pins is the right fix. ron ginger ------- Re: Need advice for drilling hardened stainless steel Posted by: "Gerald Feldman" gfeldman2904x~xxpacbell.net Date: Fri Mar 27, 2009 1:19 am ((PDT)) Alan, Not to state the obvious, but a quick search of the internet turned up a wide variety of dog "dethatching tools" of the type you describe for about 15 to 25 dollars each. As a frugal b-----d myself it really pains me to say this, but do you REALLY want to spend all that time fixing a broken tool when you can buy a new one for a few bucks. Better yet, buy the new tool, and then you can have fun and experiment on the broken one without fear of breaking one of the claws. Jerry F. ------- Re: Drill sizes [atlas_craftsman] Posted by: "Dave Hylands" dhylandsx~xxgmail.com Date: Tue Jun 2, 2009 7:52 am ((PDT)) On Tue, Jun 2, 2009, Bruce Freeman wrote: > Useful tables. SAE and Metric drill sizes. Number and letter drills > as well as fractional, and a separated metric drill table, all with > decimal inches. I was starting to compile such a table myself when I > stumbled on this one. > http://www.thelenchannel.com/1drill.php > http://www.thelenchannel.com/1drillmet.php Hi Bruce, I put one together which combines the SAE and metric into one table. Dave Hylands Shuswap, BC, Canada http://www.DaveHylands.com/ ------- Re: Drill sizes Posted by: "catboat15x~xxaol.com" Date: Tue Jun 2, 2009 8:46 pm ((PDT)) Drills. One way to get a good set of drills is to watch Harbor Fright for one of their sales. Buy one of their sets of inch and number drills. Then knowing they are junk use them one time and depending on your projects you will find that you use some sizes much more than others. (I build model steam engines and need a lot of holes tapped for 2-56, 3-48 and 4-40 so I replace those tapping sizes with good quality drill bits. Use the rest for drilling holes to hang pictures on the wall or putting up a new gate on the garden wall etc. I have a little booklet that not only gives a single tapping drill size for machine tools but also is spread out to give various drill sizes for percentage thread on machine screws. As I remember it goes with drill sizes for 100 percent thread down to 40 percent, and a note "On machine screws: a 60 percent thread will break the screw before stripping out the thread." So I aim towards a 60 percent full thread and that is a couple of sizes larger than the theory shows. Saves a lot of broken taps over the years. One thing I have learned in tapping small threads -- that if possible I hold the work piece in one hand and the tap wrench in the other hand and tap the hole "free hand". Your sense of touch will tell you if you are putting excess force on the tap and sure prevents a lot of broken taps. Of course lots of tapping fluid and back out to clear chips often. I just had a project that used a lot of 2-56 threads and did the bunch with no breakage by hand holding both the tap and the work. ------- Long thin holes [MyMyford] Posted by: "obald102" obaldx~xxihug.co.nz Date: Fri Jun 5, 2009 8:17 pm ((PDT)) How do I make (drill, bore, magic) a 3mm hole through 10cm of aluminium bar. This to be in the axis of rotation of the bar. Can you get drills that long and if you can aren't they unusably fragile? ------- Re: Long thin holes Posted by: "cliveadams79" cliveadams23x~xxaol.com Date: Sat Jun 6, 2009 12:49 am ((PDT)) Could you drill from either end, making sure you clock it up accurately when you turn the bar around? That only makes 50 mm to drill before the holes meet. I should imagine the bit would be less inclined to wander over a shorter distance too. If the bit is still too short consider extending it with a sleeve which could go in the tailstock chuck. Just a thought.... Regards, Clive ------- Re: Long thin holes Posted by: "Tony Jeffree" tonyx~xxjeffree.co.uk Date: Sat Jun 6, 2009 1:22 am ((PDT)) You could make yourself a "D" bit from a length of 3 mm silver steel rod. More robust than a conventional drill. Regards, Tony ------- Re: Long thin holes Posted by: "alan4227" a.j.moorex~xxbtinternet.com Date: Sat Jun 6, 2009 3:50 am ((PDT)) I'm intrigued. Can you tell us why you need this long thin hole? Alan ------- Re: Long thin holes Posted by: "obald102" obaldx~xxihug.co.nz Date: Sat Jun 6, 2009 11:21 am ((PDT)) I'm making marlin lures. ------- Re: Long thin holes Posted by: "cliveadams23x~xxaol.com" Date: Sat Jun 6, 2009 12:12 pm ((PDT)) In that case drill whatever size you want, counterbore the ends and make plugs to fit the counterbores with 1/8" holes. Drop of Loctite and off you go ... ;-) Happy fishing and good luck. Regards, Clive ------- Re: Long thin holes Posted by: "Frank Chadwick" fr4nk.chadwickx~xxtiscali.co.uk Date: Sat Jun 6, 2009 3:57 am ((PDT)) You can get drills that long, Axminster tools among others list them. You don't say what it is you're making, but if this is the axis of rotation, have you considered fitting ball races each end, I think the aluminium itself would present a poor bearing surface. Frank C. ------- Re: Long thin holes Posted by: "Kevin" tadpolex~xxbtinternet.com klokenz Date: Sat Jun 6, 2009 5:48 am ((PDT)) There has to be a way .. think of gun barrels. The "D" bit is an excellent idea. Slow going as you have to back out frequently to clear the chips. If you don't want to buy an extra long drill you could extend a normal one. The chances of the drill wandering off course a bit are distressingly great though, and if you need the hole to be at the centre of both ends you might well find that the best way is to first drill the hole through a piece of oversize material and then turn it between centres to bring it down to size and concentric with the hole. As regards "magicking" the hole, there's always electro discharge machining (EDM), but if you had the equipment to do the job you wouldn't be asking the question! Kevin NW England, UK ------- Re: Long thin holes Posted by: "Roman Gargulak" romanx~xxcncwings.com Date: Sat Jun 6, 2009 6:55 am ((PDT)) In my opinion, D bit would be suitable just to ream an existing hole. It is not meant to be used as a drill. Given the geometry of the tool, I think that as you get deeper into the material, it will be forced to the side and you will either break it or your hole will not be coaxial. But I may be wrong. Roman ------- Re: Long thin holes Posted by: "Tony Jeffree" tonyx~xxjeffree.co.uk Date: Sat Jun 6, 2009 9:23 am ((PDT)) Roman - You may indeed be wrong. D bit drills can be used for drilling as well as for reaming. For drilling, you need to drill a starter hole, using a conventional drill, the same diameter as the D bit drill and deeper than the length of the "halved" end of the drill, you can then drill with them just fine as long as you use plenty of lubricant & back them out frequently to clear the chips. Gun drills are a form of D-bit drill - see: http://yarchive.net/metal/gun_drilling.html Regards, Tony ------- Re: Long thin holes Posted by: "Steven Vine" microstocx~xxhotmail.com Date: Sat Jun 6, 2009 3:53 pm ((PDT)) As an exercise I made a couple of pens out of aluminium a few years back. I just drilled into the 8 mm dia rod using a 3 mm drill mounted in a drill chuck in the tailstock. After I went in as far as I could with the drill, I just reversed the rod in the 3 jaw and then drilled in from the other end. I continually cleared out swarf and didn't force the drill at all. I was slightly out when I met in the middle, but not by much at all. Just do it and see what happens. I remember seeing long drill bits in a catalogue somewhere; aircraft drills? Steven Vine ------- Re: Long thin holes Posted by: "mark" mark.brown807x~xxntlworld.com Date: Sat Jun 6, 2009 4:19 pm ((PDT)) This guy is talking 3 mm in 10 cm on a lathe ...I've done it freeehand with a 9.5 volt cordless drill. ------- NOTE TO FILE: Someone has broken off a drill bit and the broken drill fragment is fully buried in the target. This next trepanning method is worth considering, instead of the more common solutions (which often do not work very well). ------- Re: Getting a broken drill bit out of the hole [sherline] Posted by: "Marcus" marcusx~xximplant-mechanix.com Date: Tue Oct 27, 2009 9:34 pm ((PDT)) Hi Tom: This is not all that hard to fix, and it's worthwhile to learn how. You can trepan it out, you can nibble it out with an old 2 flute carbide ball cutter, or you can go at it with an abrasive point in a Dremel. It's only in there about 4 mm...that's not much more than 1 drill diameter. If you can trepan around the broken drill for even half its depth, I'll bet it will just pop right out. The easiest way to make a trepanning tool is to take a 2 flute endmill and grind a slot longitudinally down the center big enough to allow the drill into it and to a depth sufficient to get to your target depth in the job. Peck it down into the spoiled end in small increments using the carriage of the lathe rather than the tailstock. Be patient and don't push it. If you go nice and slow it will just walk its way down around the broken drill. Try wiggling the drill stub as soon as you've gone down deep enough to have a graspable end. Nine times out of ten, once you've cleared the first bit of the hole, your broken drill will come out easily. It's the burs you mashed around the break point when the drill first snapped that are likely holding it in (unless, of course you let it pack full of chips and broke the drill that way). Similarly, if you elect to try to drill it out with a carbide ball mill, use the carriage of the lathe rather than the tailstock. Make yourself a nice block with a reamed hole right on center for the endmill shank, just like a toolpost. It will be handy for lots of things especially if you put a number of reamed holes in it of different standard sizes. Cheers Marcus www.implant-mechanix.com ------- Removing a Broken Drill [taigtools] Posted by: "Jack" tech.writerx~xxearthlink.net Date: Fri Dec 11, 2009 10:18 pm ((PST)) I just drilled 56 identical holes in 6061 with my mill, and for some reason, the first bit broke when I was into hole no. 6 or 7. I changed bits and all the remaining holes came out fine. The hole that needs repair is about 0.65" deep, drilled with a #43 HSS bit (0.089"), and the bottom half of the hole is filled with what's left of the bit. I intend to tap all these holes for 4-40, so I really want to get the broken bit out without damaging the hole if at all possible. I know there are various methods for this, but the two cheapest are what I want to ask about. First, the bit is standard bright finish HSS. Is it likely that I could remove it with a short-length cobalt bit of the same size? I'm thinking cobalt might be hard enough to cut through it. Second, I Googled this problem and came across a number or articles claiming that a broken steel drill bit can be partially dissolved with mild acid. The recommended products seem to be pickle (for pickling food) and Alum, both available at grocery stores. Supposedly, it only takes an hour or two for this to work. Has anyone here tried this? Jack ------- Re: Removing a Broken Drill Posted by: "Doug Stout" kingshouse41225x~xxgmail.com Date: Fri Dec 11, 2009 10:27 pm ((PST)) I would try a 2-flute solid carbide endmill. Crank up the speed all the way and feed really slow. ------- Re: Removing a Broken Drill Posted by: "Jeff Demand" jdemandx~xxgmavt.net Date: Sat Dec 12, 2009 5:59 am ((PST)) Jack: Not that I would ever break a drill :-) The carbide drill will work but is not fun and you stand a good chance ending up with both HSS and carbide broken drills in the hole. Then you are REALLY screwed. Mild acids will eat steel but not Al. I use jewellers pickle (Sparex) or much cheaper Ph down for swimming pools and hot tubs (sodium bisulfate I believe). Mix a little strong and use warm but not boiling. An hour or two and you are good to go. Alum is also supposed to work in the same manner but I have never tried it. jeffD ------- Re: Removing a Broken Drill Posted by: "Stan Stocker" skstockerx~xxcomcast.net Date: Sat Dec 12, 2009 6:12 am ((PST)) Hello Jack, If you can drill a slightly smaller hole from the flip side and punch the bit out you might be able to recover the hole. In reality, a snapped bit usually mungs up the bore pretty well. A hollow drill is pretty easy to make; it's just a bit of hardenable steel with a #44 hole in the center and turned down to a thin wall. File a few teeth, harden, and bore down around the broken bit. Once it's clear, helicoil the hole to get good threads. Or if the application allows you could press in a shouldered plug from the back side, stake it in place, and drill and tap. Then again, if the application allows you could just forget about it. Acid will work, nitric is good, alum is slow but works. Then again, boiling parts in alum is a nice way to get some humidity back into the house during the cold dry season :-) Sometimes you can punch the broken bit a few times and it loosens up enough to pull it out. Cheers, Stan ------- Re: Removing a Broken Drill Posted by: "sherlineheretic" designnowx~xxsbcglobal.net Date: Sat Dec 12, 2009 6:52 am ((PST)) I have used some of these methods at work on big aluminum chambers in the past. I would: 1. use the nitric acid method to dissolve and pick out all the remaining pieces of bit, and 2. use the 3/32 carbide endmill (with its sides relieved to get a practical flute length of ~.700 long) afterwards to get a straight hole. Unless you are doing something unusually critical requiring every last bit of thread load-holding ability, the difference in thread strength between a tap drilled hole of .089 and .093 is negligible. If I recall, a 4-40 is .112 outside dia. A guy I used to work with who did part time work at the Lawrence Livermore Lab told me they did strength test experiments, and concluded there wasn't that much difference between 55% thread form and the usual 75% we all use daily. Just be sure you get all of the old bit out before you tap the hole! That'd be a booger to try to get out (yes I've done that too). If all else fails, use a larger carbide endmill and tig the hole full/shut. Then mill off any bump from the tig and drill and tap as usual. I hope it fixes easily for you. Ken ------- Re: Removing a Broken Drill Posted by: "Jack" tech.writerx~xxearthlink.net Date: Sat Dec 12, 2009 10:08 am ((PST)) Wow, thanks for all the good ideas! The part is fairly large, about 17" long and 4" high, so I can't dunk it or drill in from the other side. Guess I'll try to drop some nitric acid or something similar into the hole first. Incidentally, here's the part: http://jackandkelly.zenfolio.com/img/v6/p454564355-3.jpg http://jackandkelly.zenfolio.com/img/v8/p233431289-3.jpg The bit originally broke off just above the surface. When I tried to twist it out with pliers, about half of it came out. The piece left at the bottom seems to be jammed, but maybe the acid will loosen it enough. I think the hole will be OK to tap if I don't damage it further through the extraction process. Worst case, I'll get it helicoiled as suggested. One thing funny - when I told my wife what happened, she asked if a new drill bit would be expensive. :) Thanks again! Jack ------- Re: Removing a Broken Drill Posted by: "Jeff Demand" jdemandx~xxgmavt.net Date: Sat Dec 12, 2009 11:14 am ((PST)) Jack: A plasticine damn will contain most acids with no problems. If you were using oil for drilling try to wash it out as a first step before the plasticine. The swimming pool stuff is easier to buy than nitric, cheap, and won't put a flag on your homeland security list. Get the wife to buy you 2 replacement drills before she realises that you just made a careless dumb assed mistake. No cosmic conspiracy involved. jeffD ------- Re: Removing a Broken Drill Posted by: "Jeff Demand" jdemandx~xxgmavt.net Date: Sun Dec 13, 2009 5:59 am ((PST)) On 12/13/2009 at 1:10 AM Bertho Boman wrote: >Am I correct that you are referring to hydrochloric acid= muriatic acid >when calling for pool chemicals? Bertho, The pool stuff I use is a sodium bisulphate or sodium meta bisulphate. Ph Down or some such name. I use it instead of sulphuric acid, not nearly as bad but will still eat your clothes in a couple of washes if carelessly splashed about. I don't record nor measure the concentration, probably 2-3 table spoons of crystals per pint of water. Not rocket science, and the fumes from it when hot will rust nearby steel. Keep covered well and a little will last a long life time. jeffD ------- [HERE IS A DRILLING OR MILLING TRICK FOR CENTERING ON ROUND STOCK] Re: Phase II BXA toolpost system on sale at Enco [atlas_craftsman] Posted by: "L. Garlinghouse" lhghousex~xxsuddenlink.net Date: Fri Dec 18, 2009 6:53 am ((PST)) Glenn N wrote: > It is also a neat trick to use on the drillpress or mill when drilling a hole in a round object. Orient the drill bit so the straight chisel edge of the web lines up with the cylinder you are boring and the rule will be parallel to the table when you are lined up. < Glen: You just gave me an "Oh Yeaahhh" moment. You know, when you hit the middle of your forehead with the heel of your right hand and exclaim "Oh Yeaahhh!!." Of x~xx$$%%## course!! I've known the centering the tool on the side of a horizontal shaft trick for years . . . . why oh x~xx##$$!! why didn't it occur to me that it just might work off of the top of a round shaft ??!! Oh Yeahhh!!! I need to go put some ice on my forehead. Later, L.H. Garlinghouse Arkansas ------- Drilling advice desired [sherline] Posted by: "Mike" mlucekx~xxmindspring.com Date: Mon Jan 25, 2010 11:16 am ((PST)) I'm starting to build the Little Machine Shop's oscillator engine on my Sherlines: http://www.littlemachineshop.com/Projects/OscillatingEngine.php I'm wondering what's the simplest way to drill the holes (tapped 10-32) in the end of the upright (3/8" x 2" x 4.1") that attaches to the base. There's not enough room under the mill spindle to mount the upright (4.1" tall) and drill that way. There's only a couple of inches left under the drill chuck after putting that upright onto the mill table (e.g. clamped to a right angle plate) which doesn't leave any room for a conventional drill bit. Options that I can do : 1) drill press - since those holes are not critical to anything, probably the simplest option (K.I.S.S.) 2) convert mill to horizontal configuration (have that accessory, using the horizontal base as my full-time base for the mill anyway) - more complicated since I'd have to retram the mill in the horizontal config and then when I put it back to the vertical config. Would be a good learning exercise to fiddle with the horiz mill config :) 3) drill using lathe, mount the upright piece on the lathe cross slide at appropriate height (using spacers/shims); drill bit in 3-jaw or mount drill chuck in lathe headstock. 4) buy a bigger mill ....... :P 5) use someone else's larger mill 6) vice and electric drill 7) dremel with drill press conversion stand 8) choose another engine model to build 9) get z-axis extension blocks from Sherline or A2Z 10) throw up my hands in the air and have a beer .... pros/cons : 1) is quickest and simplest 2) probably the best learning experience, 3) another decent learning experience 4) longest lead time and most expensive 5) would be easy, but have to find a local buddy who's mill I could use. 6) crudest and least accurate 7) dunno if large enough drill bit for dremel ? cheesy 8) lots of other models to build LOL 9) might be useful in the future, but costs $ 10) really the simplest and least effort required other then to get off my carcass and run to the fridge ..... Steam Engine Lager is a nice micro-brew from Durango, CO :D Any advice, I'm leaning towards #1 or #2, with #10 as the ending result :D Mike ------- Re: Drilling advice desired Posted by: "thayerx~xxgryffinaero.com" tcsyme Date: Mon Jan 25, 2010 11:34 am ((PST)) Mike: Hands down, #1 if your drill press is up to the task and the main goal now is to make a fun little engine instead of fidgeting with your tools. I would head on over and be done with the job in a few moments. #2 No reason to retram the mill twice going to horizonal and back for just two non-critical holes. I would drill the base plate at the same time, and use it as a guide to locate the holes in the upright. One thing this would teach you is to not do it this way again. #3 If you didn't have the DP, I would next recommend the lathe, possibly with the milling vise on the cross slide if you couldn't shim accurately to mid thickness. keep in mind that those holes can be anywhere, as long as they don't blow out the side or into the main bearing. #4 would be good, but will take a long time. #5 Calling someone else and setting up a time may take longer than doing it in the drill press. #6 and 7 are about the same level of "accuracy" in my experience. #8, naw, it looks like a fine little runner. #9, hard to justify on this one between cost, time and lack of need for absolute precision this time. #10, a must, but wait until you have the holes done. Or better yet, the engine running. Thayer ------- Re: Drilling advice desired Posted by: "chieftoolmaker" chieftoolmakerx~xxearthlink.net Date: Mon Jan 25, 2010 11:45 am ((PST)) Yo Mike, #1 with a modification. Make a simple drill jig (with drill bushings # 21) with accurate hole locations where required dropped in on the mill. Clamp it on the upright and drill. Change bushings (# 12) for the tapping.... follow with 10) :) Then face New York, snap a salute to; Sgt Glick aka Jerry G ------- Re: Drilling advice desired Posted by: "n2562001" jlkiefferx~xxcharter.net Date: Mon Jan 25, 2010 12:34 pm ((PST)) Mike: For this type work I use collets to hold drills where clearance is a problem. This allows the drill shank and fluted portion if required, to be extended up into the spindle leaving only what is required in front of the collet. For just a couple of holes, you can also use a three jaw lathe chuck in the same manner if you do not have collets. This will allow you to spot drill the holes as well as drill them in the proper location by handwheel/slide settings. Jerry Kieffer ------- Re: Drilling advice desired Posted by: "thayerx~xxgryffinaero.com" tcsyme Date: Mon Jan 25, 2010 12:47 pm ((PST)) While the rest of us are too worried about drinking beer, the master comes up with an eminently suitable solution that removes nearly all of the chucking dimension from the equation. Thanks Jerry. Thayer ------- Re: Drilling advice desired Posted by: "Forrest A" atkinonx~xxhotmail.com Date: Mon Jan 25, 2010 1:57 pm ((PST)) I solved the clearance issue with a taller column that Sherline offers. I highly recommend it. My opinion for what you are doing: In your case though I would just lay it out and drill the holes with a drill press. Use a good, prperly shaped prick punch and loupe with carefull layout and vise/rigid fixture and the holes will turn out fine on a drill press. FBA ------- Re: Drilling advice desired Posted by: "R.L. Wurdack" dickwx~xxnwlink.com Date: Mon Jan 25, 2010 4:18 pm ((PST)) If it hasn't been mentioned yet I would like to add that the set of numbered stub drills that I bought from MMC turns out to be very handy with the Sherline - both mill and lathe. Dick ------- [SMALL DRILL BIT SHARPENING JIG] Small Drill Jig [myfordlathes] Posted by: "used to be Buddy. ( Holly )" d.j.wilsonx~xxmac.com Date: Fri Feb 12, 2010 10:59 am ((PST)) Can someone save me going nuts. Been looking around sites for a jig I've seen for sharpening small drills. The jig was made from some heavy extruded aluminum angle, with a small pin vise held in the corner of the 90, so that it bisected the angle. A small drill being set up so that it could be rubbed along a Stone/Diamond lap, or even a piece of wet and dry sandpaper; and after doing one facet, the angle was then flipped to present the other face. So neat and simple. I today collected Harold Hall's book on "Tool and Cutter Sharpening" which is a good read for the money. But nothing like this tool is in there. Dave ------- Re: Small Drill Jig Posted by: "john56552" john.777cordenx~xxbtinternet.com Date: Sat Feb 13, 2010 4:40 am ((PST)) A search for 'Drill Sharpening' on Madmodder reveals: http://madmodder.net/index.php?topic=2552.msg27040#msg27040 John ------- NOTE TO FILE: The above webpage shows two sharpening jigs, one of which would be easy to make. ------- Re: Small Drill Jig Posted by: "DAVID WILSON" d.j.wilsonx~xxmac.com Date: Sat Feb 13, 2010 5:53 am ((PST)) Is there anything special about the DAG, that I should see before making this simple small drill jig.? Dave ------- Re: Small Drill Jig Posted by: "c j.s" callinicus1953x~xxyahoo.co.uk Date: Sat Feb 13, 2010 11:19 am ((PST)) Hi David: Nothing really, except it is capable, depending on which version, of sharpening down to #60 drills with a four facet cutting edge or the bigger version will do the same grind up to 1/4". Check out http://www.gadgetbuilder.com/DrillSharp.html and scroll down to "a four facet drill sharpener" where you will find a modified Derek Brown sharpener. The original jig was written up in ME many years ago but if you haven't got old copies, the Gadgetbuilder's one should work just as well. If you do make one and sharpen very small drills, you will find that you need to make a magnifier, also on the site, unless you have "super-vision", far too much Kryptonite around here for me to see without one! cj(UK) ------- Horizontal boring set-up [shopbuilttools] Posted by: "The wizz" wizz2_usx~xxyahoo.com Date: Fri Jul 2, 2010 7:49 am ((PDT)) Anyone have a set up for horizontal drilling? ------- Re: Horizontal boring set-up Posted by: "Barry Wilson" barrywil47x~xxyahoo.com Date: Fri Jul 2, 2010 8:15 am ((PDT)) On my shopsmith. Barry ------- Re: Horizontal boring set-up Posted by: "Terry Ney" tney88x~xxyahoo.com Date: Fri Jul 2, 2010 8:18 am ((PDT)) That is one feature of the Shopsmith which, while you don't need it often, when you do there is nothing that does it better. I've seen old Shopsmiths on CraigsList as low as $50, and heard stories of folks picking them up free, sometimes curbside ahead of the garbageman. So before I spent hours and many $ trying to build a horizontal boring machine, I'd look around for an old SS. If you're determined to build one, I'd suggest using an inexpensive imported drill press head for the headstock, and just fabricate the table and base. Terry Ney ------- Re: Horizontal boring set-up Posted by: "gdnicholsx~xxaol.com" gdnicholsx~xxaol.com Date: Fri Jul 2, 2010 8:36 am ((PDT)) The old Sears radial arm saw book shows how to rig the saw to make a horizontal boring machine. They had a collet-style chuck that went on the accessory shaft opposite of the blade (you could also screw on a Jacobs- style chuck.) The saw's x-y-z adjustments would give a lot of drilling flexibility, but it always seemed to me the saw motor turned way too fast to be used as a drill. Dale ------- Re: Horizontal boring set-up Posted by: "kendall bonner" merc2dogsx~xxyahoo.com Date: Fri Jul 2, 2010 10:06 am ((PDT)) They are a bit too fast for most drilling. I have one of the old recall types, very strong and rigid compared to most of them I've seen. Most often it's used as a sander, with rare use as a saw..... Thought of building an auxiliary motor mount for a variable speed head, or reduction setup for it to increase its versatility. The old Wards radial arms had three speeds available on separate output shafts. Drawback was that they were always engaged and made for a noisy motor. The sears is a pretty quiet machine overall ------- Re: Horizontal boring set-up Posted by: "Tom Jones" tomjonesx~xx1scom.net Date: Fri Jul 2, 2010 12:57 pm ((PDT)) I use my radial arm saw with a chuck that screws on to the bolt for the blade. I got both the bolt and chuck off an old drill press. It also works for routing, but not as good as a router table. Tom ------- Re: Horizontal boring set-up Posted by: "Barry Wilson" barrywil47x~xxyahoo.com Date: Fri Jul 2, 2010 8:40 am ((PDT)) Also could set up fence on drill press and drill vertically. Barry ------- Re: Horizontal boring set-up Posted by: "Richard" wizz2_usx~xxyahoo.com Date: Fri Jul 2, 2010 12:20 pm ((PDT)) NO can do. object too long. Richard http://www.PictureTrail.com/gallery/view?username=thewizz ------- Re: Horizontal boring set-up Posted by: "gdnicholsx~xxaol.com" Date: Fri Jul 2, 2010 8:52 am ((PDT)) Barry: That is what I've done most often...just turn the drill press table sideways and clamp the work to it for horizontal drilling. The only problem with this technique is that you have to do a lot of adjustment if you have multiple holes to drill. There are several plans on the Internet to make various fences that clamp to a flat DP table for horizontal boring but I have never gotten around to building one. You've seen the 90 degree router table where the router is mounted horizontally rather than the usual vertical orientation? Using that plan, you could mount a cheap Port-a-Line or similar drill holder where the router should be and you'd have a horizontal boring machine with x-y-z adjustment for very little expenditure. Dale ------- [Drilling holes in concrete to mount machinery.] Re: Machinery Setting [was:Re: Top Posts VS Toolposts] [atlas_craftsman] Posted by: "L. Garlinghouse" lhghousex~xxsuddenlink.net Date: Mon Jul 26, 2010 2:41 pm ((PDT)) Dan Buchanan said [in part]: > Or a bottom frame that sits on 4 large rubber machine mounts. > Or boltdown the only way to go? > Personal preferences expected, and greatly appreciated, thanks. To which I comment that if you have a heavy enough base/frame you can get away with just gravity and shimming. Just don't mount a vise to it or let chattering to develop into a harmonic and get the whole mess dancing. So how heavy is heavy enough? Heavy enough it doesn't dance around or vibrate. [The original "bench" for my Atlas 10"F TH42 was "heavy enough." It was a large chunk of 5/8" plate with like 10" Channel iron legs. Built and used in a place with an over head crane.] I moved that once in what was to be my last move ever. The move after that I scrapped it and when I got a shop, built a frame out of the light 8" or so "H" beam that had been the tongues of my double wide modular factory built home. That worked out just fine except the frame would easily twist about 1/2" in the free state. Once bolted to the floor, it worked out just fine. So a light frame/bench requires bolting down. I'm building a frame for another lathe and I have enough heavy weight free stuff that I am thinking of doing the adjustable rubber feet thing. [3/8"x4x4 angle, 3"x 2-1/2" SQ Tubing]. If my welding sequence is off and it distorts, then I'll end up bolting it to the floor. Bolting it to the concrete story: I laid out the pattern in the floor and had bought a 1/2" drill motor at Harbor Freight to drive the carbide masonry bit. I cleverly made a dam out of modeling clay around the hole site and once going added water to cool the drill and move the slurry to the top. Worked fine for 3 holes. On hole #4 I hit a piece of aggregate and the drill walked off of center about 3/8". It was Sunday and Lowe's and Home Depot were 35 miles away. No star drill in my shop. Calling on my inner Wily E. Coyote, I found a piece of rebar the right size, cut off a length about 12" long, ground both ends sorta smooth and perpendicular with the longitudinal axis, and then on the business end used a hack saw followed by a triangular file to cut some cross grooves at about 90 degrees to one another. I did them close enough to each other that a sort of blunt Vee was formed. I heated the business end up to red hot and quenched it and went to work. Worked like a charm. In some ways it was easier than wrestling the 1/2" drill motor as I got to sit down and just hammer and turn the drill. I probably would have had to resharpen about every hole or so, but it beat putting the job off or getting cleaned up and driving 30 miles. Also I was able to sense where the offending aggregate was and get the hole back on location. Although there are those who now think of me as Arkansas Trailer Trash, I prefer to think of myself as a modular factory built recyclable. Later, L.H. Garlinghouse Living the Arkansas dream: Unemployed living in the county in my not too old double wide and collecting my gubmint check. Jest don't git no better'n that. ------- Re: Looking for Drill Pad #1 Morse Taper [atlas_craftsman] Posted by: "oldstudentmsgt" wmrmeyersx~xxsbcglobal.net Date: Sun Aug 8, 2010 5:24 am ((PDT)) "pep" wrote: > Anyone know where I can find a Drill Pad with a #1 Morse Taper? > I have seen lots with a #2 Morse Taper but they won't fit my > tailstock which is #1 Thanks, Pep You can make one with a MT1 drill chuck adapter and a small metal plate. Shars and CDCO have the adapters in a variety of drill chuck tapers, get one, turn & thread the chuck taper to fit a drilled and tapped hole in the plate, and you're good to go! CDCO has "Drill Chuck Shanks" in MT1 & JT1 for $5.00. Look at www.cdcotools.com and click on the "All Kinds of Die Makers Tools" link, then scroll down... I've got some in MT2 I got for my 7x HF lathe. Bill in OKC ------- Drill Chuck in Mill [taigtools] Posted by: "Jack" tech.writerx~xxearthlink.net Date: Tue Sep 7, 2010 6:29 am ((PDT)) Whenever I use a #9 drill (0.196"), I have to force it into the 3/16" ER collet. It works, but this size drill really needs a 7/32" collet, which Taig doesn't sell. So, I'm thinking about buying the 1140ER drill chuck arbor from Taig and using Taig's 1/4" or 1/2" Jacobs chucks on the mill. Should I be concerned about accuracy or other issues when I do this? The chucks would be used strictly for drilling, not milling. Alternately, Ico uld look for the correct size collet from a third party. Anyone have any experience with this issue? ------- Re: Drill Chuck in Mill Posted by: "Steve Blackmore" stevex~xxpilotltd.net Date: Thu Sep 9, 2010 12:34 am ((PDT)) Use a 5mm ER collet. Do not force it into one that is too small. Steve Blackmore ------- Re: Drill Chuck in Mill Posted by: "Ken Cline" clinex~xxfrii.com Date: Tue Sep 7, 2010 7:12 am ((PDT)) Get the drill chuck. Drilling is not a precise operation, even when the bit is held in a collet, so I see little downside to using a drill chuck. Always start the hole with a spotting (or center) drill. Finish with a reamer if you need accuracy. I only own reamers in common fractional sizes (1/8, 1/4, etc.), which assures me I have never needed a precision #9 size hole. Most often I use good old #9 to drill 10-32 clearance holes, and a cheap drill chuck works just fine for that. ------- Re: Drill Chuck in Mill Posted by: "Tim Voght" tvoghtx~xxindy.net Date: Tue Sep 7, 2010 7:12 am ((PDT)) No experience using it with the Taig mill, but I use the 1140ER arbor in a 3/8 collet (with the 1/4" chuck) in my Bridgeport. Very happy. Have never actually measured runout, but the usual Taig quality can be depended on. Tim ------- Re: Drill Chuck in Mill Posted by: "Adam Collins" rxforspeedx~xxyahoo.com Date: Tue Sep 7, 2010 9:49 am ((PDT)) Jack, try www.maritool.com While not as inexpensive as the collets Taig sells, these are top quality with a very small T.I.R. and made here in the USA. Adam ------- [taigtools] Some comments on layout work WAS: Re: [taigtools] Re:Auto center pun Posted by: "n2562001" jlkiefferx~xxcharter.net Date: Wed Oct 20, 2010 10:18 am ((PDT)) "Jeff Demand" wrote: > Making jewellery I find the need to drill many small holes. Work hardened centre punches is a real problem with .75mm drills. I have used a very small ball burr (.5mm) in a flex shaft, if I miss slightly it is easy to drag the depression. It is very shallow Holes where I want them and fewer broken drills from punching though work hardened metal. Another trick is no death grip on the drill, if it jams I want it to spin in the chuck rather than break. jeffD < Jeff: I also drill many small holes that must be accurately located. In the beginning it offered many challenges but I have worked out efficient solutions over the years. Most of what I consider small holes are well below .75mm, but .075mm is still small. At any rate, most success has come by the following procedure. Almost all small drilling is done in a milling machine. This allows for accurate collet mounting of a drill to prevent runout that in turn prevents breakage. It also offers depth control and mounted Optical observation if breakage must be avoided at all costs. In addition the Mill slides offer an accurate method of positioning a work piece. At this point I do not center punch or provide a depression for drill location. Personally, I find that small drills unlike larger drills wander all over the place when a punch mark or depression is used for location. What I do is lightly scribe the location with a tiny "X". Next the tip of the drill is positioned in the center of the "X" by eye sight or Optics or just a very light spot touch of the drill. For this type work I use HSS or carbide spade drills. A small spade drill can be used as a spotting drill and a drill all in one operation. If the hole is deeper than normally drilled with a Spade drill, I change over to the same size twist drill when the spade limits are reached. When working with irregular surfaces, I first spot the location with a two flute centering endmill of the same size as the hole or slightly smaller. This provides a flat surface for the Spade drill to accurately center drill the hole. I will post Photo`s of a .75mm spade drill, two flute endmill and optical mounting under my name. Jerry Kieffer ------- Re: Some comments on layout work WAS: Re: [taigtools] Re:Auto center Posted by: "Jeff Demand" jdemandx~xxgmavt.net Date: Wed Oct 20, 2010 10:49 am ((PDT)) Jerry, I do drill smaller holes, just not as often. The .75mm was picked at random so as not to scare too many people :-) I also usually work with hand held tools, jewellery bench type work. Your method is proper and more accurate but drilling lots of holes in a cluster setting which will have wires soldered in as claws doesn't require your level of accuracy. The claws get bent anyhow and if I do the job in an hour and adjust when setting it will look almost the same unless a microscope is used. Customers don't use scopes, and bosses would really freak at the extra time for stuff they can't see with a 10X loupe. jeffD ------- Some comments on layout work WAS: Re: [taigtools] Re: Posted by: "DennisF MacIntyre" a1g2r3ix~xxyahoo.ca Date: Thu Oct 21, 2010 3:16 pm ((PDT)) While reading what the above post refers to - I thought of what I sometimes will do if I do not want to bother with a center dab. I just run the drill backwards to make an indentation. I find the drill stays in one spot instead of dancing about; I then switch to forward cutting direction without lifting the hand drill and am able to drill the hole where I wanted it to go. Works for me. Keep Smiling dennis mac ------- Re: Auto center punch? Posted by: "Don Rogers" Donx~xxCampbell-Gemstones.com Date: Wed Oct 20, 2010 10:44 am ((PDT)) ""Probably not. With an auto punch, if you do not press on it perpendicular to the work, The dimple will skew. This is also true with a manual punch. It may be easier to hold a manual punch perpendicular to the work though."" When I was on my apprenticeship, my first journeyman taught me to find the crossed lines, and then very lightly tap the punch. Then check to see if you were at the cross or off to one side. If you were off you could walk the punch mark back to the center by leaning the punch in the direction you wanted to go and tap it until it was centered, then give it a good solid tap to make it even. I guess doing that with an automatic punch is out of the question as you get the final product the first time. I do find the automatic easier to hold on mark once you have found it though. Bottom line is use what you are used to and gets the results you want. Both work. Don ------- drilling 316 stainless [atlas_craftsman] Posted by: "JeffD" jefdaviesx~xxsbcglobal.net Date: Tue Nov 23, 2010 9:17 pm ((PST)) Hi guys, I have not broken my lathe lately. But am making a rear brake rotor for an old motorcycle, of 1/4 stainless plate -- I am trying to drill a lot of holes -- Boy, that stuff does not want to drilled. Any success stories? Kindest regards JJ ------- Re: drilling 316 stainless Posted by: "Scott Henion" shenionx~xxshdesigns.org Date: Tue Nov 23, 2010 9:26 pm ((PST)) Stainless work hardens. It also tends to be opposite to regular steel in tempering (fast cooling anneals it, slow cool hardens). You need a sharp HSS or cobalt drill going slow and a lot of force. Don't let the drill spin on the surface, it must cut on each rotation. Low force and higher speeds will just harden the metal. It is a pain to drill ;) I have a cheap drill press that won't go slow enough. I'm tempted to add an intermediate pulley to slow it down more and give higher torque for drilling slow with a lot of down force. Scott G. Henion Craftsman 12x36 lathe http://shdesigns.org/Craftsman12x36 ------- Re: drilling 316 stainless Posted by: "Gregg" W5IDXx~xxsbcglobal.net Date: Tue Nov 23, 2010 9:29 pm ((PST)) Can you use a ball end-mill. What size holes? There are a lot of options including high end drill bit. Stainless usually wants to grab. Are you using a cutting fluid? Try a Guhring cobalt with firex coating or a Cleveland Cobalt bit! Drilling to the diameter in 2 steps can help. Gregg ------- Re: drilling 316 stainless Posted by: "KC" kandnx~xxwindstream.net Date: Tue Nov 23, 2010 9:29 pm ((PST)) Use Cobalt bits, Tap-Magic and keep spindle speed low, feed rate up. This is what works for me Kris ------- Re: drilling 316 stainless Posted by: "David Beierl" dbeierlx~xxattglobal.net Date: Tue Nov 23, 2010 9:36 pm ((PST)) I [think I] know one thing -- you have to make sure the drill starts cutting from the first moment and doesn't rub even for a moment any time during the cut because the s/s will work harden. That means lots of feed pressure. Extrapolating, I'd guess that a pilot-point or split-point drill would be a good idea, since you don't want the chisel edge rubbing the work. Yours, David Beierl -- Providence RI USA Atlas 618 6"/3/index.html" lathe ca. 1941, shiny-new Taig mill. ------- Re: drilling 316 stainless Posted by: "Jon Elson" elsonx~xxpico-systems.com Date: Wed Nov 24, 2010 9:16 am ((PST)) Get a Cobalt drill bit, and keep the feed aggressive. If you lighten up the feed, even for a second while changing hand positions, the material can work-harden, and then you'll have horrible screeching and burning. Jon ------- Re: drilling 316 stainless Posted by: "Dan Buchanan" db45acpx~xxyahoo.com Date: Wed Nov 24, 2010 11:07 am ((PST)) Try starting with a much smaller spotting drill and then finish with a cobalt drill bit to specs. It helps assure the drill bit will bite and begin cutting. As long as the included angle of the spot drill is the same as the drill size it should work fine. Use a slower speed with cutting fluid. Works for me. Dan ------- Re: drilling 316 stainless Posted by: "Richard Marchi" rfmarchix~xxaol.com Date: Wed Nov 24, 2010 3:16 pm ((PST)) I agree with the advice on drilling SS. Sharp bit, 50 fpm, high force, constant feed producing chips, sulfurized cutting oil... good luck. Richard Marchi Washington, DC ------- Re: drilling 316 stainless Posted by: "Tom Johns" tj_98520x~xxyahoo.com Date: Wed Nov 24, 2010 8:34 pm ((PST)) I have been drilling and tapping 316L stainless where I work at the Little Hoquiam Shipyard for the last 33 years and the cutting fluid that works best is Truetap HD cutting fluid. http://www.amazon.com/CRC-03400-Truetap-Cutting-Bottle/dp/B0013J1UJW All the other posts are dead on about slow speed, high pressure and a sharp drill bit. Use this cutting fluid and you won't want to use anything else. Good luck with your project. Tom ------- Re: drilling 316 stainless Posted by: "chrisw" in2steamx~xxwi.rr.com Date: Fri Nov 26, 2010 3:43 am ((PST)) I know it's after the bell but I wanted to ring in with my cutting fluid choice and that's pasty green stuff called "anchor lube". I machine/drill 304 most of the time for dairy industry were I work. It has a food grade rating unlike tap magic, but I use both anyway. The anchor lube seems to work better on smaller high speed drills and mills. Match your cutting speed which is 60 fpm for 316 to your drill size as close as possible. I always find a better material then SS for my own personal use, I just dislike it now. I hate SS in 304 especially since working in the dairy industry. Its only attribute I like is that it does not rust normally. Chris ------- Re: drilling 316 stainless Posted by: "jo barden" jobarden422x~xxmsn.com Date: Fri Nov 26, 2010 4:39 am ((PST)) Stainless is a pain in the back side. I have used it for boilers but you have to be careful about pressure and temps, it work hardens/gets brittle/ cracks. I only use it for pistons and connecting rods/piston rods on small steam engines. An old dodge I use is to grind it obliquely and use it as a reamer when making packing glands a lot more steam tight before using graphited/ptfe yarn. ------- NOTE TO FILE: See a conversation in the file here called "Sherline Mill Quirks or Tips" with the subject Work Holding starting Dec 1, 2010 for tips when using a milling machine that can rotate the head to horizontal. This idea is adaptable to horizontal drilling with a radial arm saw. ------- Re: Morse Taper (tailstock) slips [atlas_craftsman] Posted by: "Russ Kepler" russx~xxkepler-eng.com Date: Tue Mar 8, 2011 6:27 am ((PST)) On Monday 07 March 2011 ranchero60 wrote: > I drill holes all the time on a Haas VF-2 0.010 dia. to .040 dia. with > a carbide micro drill and the are held to less than +/- .0005 so a lot > depends on the working conditions the accuracy of the drill and the > drilling pressures applied. > Our Hardinge tool room lathes are manuals and with a new or freshly > sharpened drill they are usually +/- .001 in diameter. Just do not push > the drill hard and you get a lot better hole and can hold a tighter > tolerance. The problem is that the hole produced by a drill is dependent on the centering of the point - if it's off center the drill cuts oversize. If you cut a pilot hole for it the drill will follow the pilot and again if the length of the flutes differ because of an off-center point the drill will cut oversize. A core drill will resist this to some extent but it can also go oversize. Generally, if you want a hole really on size you're going to want to ream or bore it after drilling up close. If you want it on position you have to drill and bore it out with a single point tool. A single point tool has equal deflection all around a hole so the hole appears directly under the spindle and can improve the hole location over the drill. When I'm trying to get jig bore accuracy on my mill with DRO on multiple holes I first spot drill, drill to .025 under, bore to .005 under, then ream to size. That way the holes are on size to .0001 and on location to .0002 (likely +- .0001 and .0002 on each -- all I can tell is from matching multiple pieces -- 16 holes on each with precision dowel pins through both). Not too bad w/o a jig bore. But most of the holes I drill are for bolts or for tapping and so I just mash a drill through and count it as good. A couple thou on anything larger than .125" for either type of hole isn't worth worrying about. Drills are for the rapid removal of material, not for precision placement or size. If you put a lot of work into the drill you can get acceptable results, some folks can get good results, but you won't see that level of work put into the tool in a production environment under any normal circumstances. ------- NOTE TO FILE: There have been a lot of drilling discussions over the years in these groups, but the next one is particularly informative about achieving small but extremely accurate holes. The subject line mentions brass but these methods are applicable to any project needing precision. ------- [sherline] Drill holes in .031 Brass Square. How to keep the drill from walking Posted by: "len_woodruff" sbcsystemsx~xxgrandecom.net Date: Sun Mar 6, 2011 5:53 pm ((PST)) I need to drill some .018 to .020 holes in the center of this sqaure brass. Is it better to use the Lathe or the Mill? I only need to drill a hole about .125 to .250 long. I tried it in my mill tonight and it broke the bit because it seemed to be walking a tiny amount after about .0675 inch. ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "JERRY G" chieftoolmakerx~xxearthlink.net Date: Sun Mar 6, 2011 7:36 pm ((PST)) Hi Len, Wow! At .018" or .020" dia. drill that is a max of 12-13 diameters! Are you using a twist drill? Are the decimal points in the right place? LOL Jerry G (Glickstein) ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "n2562001" jlkiefferx~xxcharter.net Date: Sun Mar 6, 2011 9:48 pm ((PST)) Len: I have drilled many .020" holes that were at least .250" deep in brass without issue over the years. My personal Methods are as follows (1) Hole location must be spot drilled before drilling regardless of the use of a lathe or Mill. (2) You must use the highest quality drills available that are center ground. (USA made preferable.) Poor quality drills from China and India sold by places like Harbor Freight, Home Depot, LMS etc. are not going to cut it. (3) Drills should have little to no spindle runout. They can be held in WW collets in the mill and center aligned with an adjustable chuck alignment accessory in the lathe. (4) I use a slower rpm of about 1000-1500 rpm with a slow rate of feed and plenty of cutting fluid. This allows the the drill to cut with less stress but requires frequent removal of the drill to clear chips. Drill stress can be easily and effectively monitored with optical observation. When using the Lathe, the use of the 2.5" "Z" axis Mill handwheel on the lathe tailstock gives a far more consistent controllable feed rate. Jerry Kieffer ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "Ian Newman" ian_newx~xxyahoo.com Date: Mon Mar 7, 2011 12:01 am ((PST)) Hi Len: The easiest way to drill small holes is free-hand in the lathe. When drilling small holes, the trick is to rotate the work rather than rotate the drill -- in this way as the drill starts to wander the forces on the cutting edges force the drill back on centre. If you do this there is no need to use a precision spindle or to run at very high speeds. Watchmakers have used the technique for a couple of hundred years. It is impractical to use a conventional centre drill so I use a graver to "catch the centre". To demonstrate the method that I use to drill small holes, I've uploaded some video to youtube showing the drilling of a 0.5mm hole through a piece of brass about 12mm deep (0.020 dia by 0.5 inch deep) -- there are four clips: The graver. http://www.youtube.com/watch?v=lZ7PP4KgzmU Catching the centre. http://www.youtube.com/watch?v=f8IDhos0Qtw Drilling the hole. http://www.youtube.com/watch?v=maUtJ2UBuMs The finished hole. http://www.youtube.com/watch?v=hiXwU0qn9s0 You do not need to use high spindle speeds or a special precision spindle and collet system. You do not need expensive drills -- remember that watchmakers used simple spade drills with this technique. Do not attempt to mark the centre with a conventional centre drill or centre punch (the drill is too coarse for a 20 thou hole, and centre punches are only used by blacksmiths....) Ian ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "n2562001" jlkiefferx~xxcharter.net Date: Tue Mar 8, 2011 8:26 am ((PST)) JERRY G wrote: > Hey, > Mr. Good Buddy! > Have you ever done/tried ? > Mr. Chief aka Jerry G (Glickstein) Hey Chief: Depends on your definition. For larger holes of about #80 and above, I generally use a very slow consistent rate of feed clearing chips as required. For smaller holes, I slowly advance a drill for a very short distance and clear chips if need be or not. This is repeated under Optical observation until the hole is drilled to the desired depth. This is of course ONLY done under leadscrew control to prevent drill breakage. A leadscrew will not allow a drill to be pulled into the work piece creating sudden stress that can break the drill. I suppose this could be called peck drilling. However, When I think of Peck drilling, I think of a procedure sometimes used in Horology. At this point I would like to make it clear that I mean no disrespect to anyone, but this is a very sore subject to myself personally. What I think of, is the freehand use of a pin vise and drill by those who have not yet mastered sound procedures and skills. With close optical inspection, I have yet to see a hole done using this procedure that was round, not tapered and actually centered. In Horology as an example, small holes are generally drilled for the replacement of pivots. This requires a quality hole that is centered, round with parallel sides for proper friction fitting of a new pivot. And for tight clearance to retain strength in the work piece in some cases. Anything less can allow a replacement pivot to work its way loose. When it comes out, it can allow a sping loaded movement to damage itself. While no big deal on a common inexpensive movement, but a tragedy on an expensive collectable movement. The rub for myself personally with procedures such as this is that I teach Horological work shops. In doing so, I need to spend time on teaching difficult procedures to correct work done in this manner rather than moving on. Then of course everytime I find that one nice piece I would like to own, someone has cobbled something up that may or may not be able to be corrected. Now that I have vented off course, I will shut up and get back to work. Jerry Kieffer ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "JERRY G" chieftoolmakerx~xxearthlink.net Date: Tue Mar 8, 2011 8:33 am ((PST)) Mr. Good Buddy! Thank you for the explanation..... When you "vent " it is cool, and I learn a great deal...... Mr. Chief ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "Wayne Brandon" tiktokx~xxcox.net Date: Tue Mar 8, 2011 10:29 am ((PST)) AMEN brother Kieffer: I mean no sacrilege but I have seen bungling on clocks that borders on sacrilege. Those of us who try to preserve old timepieces are caretakers of history and should first do no harm. I once had a lantern pinion, on an arbor purchased from S. La Rose, come apart. Since then I don't trust any part I buy without careful inspection/ rework. Regards, Wayne in Arizona ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "Ian Newman" ian_newx~xxyahoo.com Date: Tue Mar 8, 2011 11:50 am ((PST)) Hi Jerry K, I assume the comments you made about "the freehand use of a pin vise and drill by those who have not yet mastered sound procedures and skills" refer to me (and the content of my previous post). I agree that I probably do not have as much experience as yourself - I have only worked with machine tool since 1969 and have only been employed as an instructor for 17 years. Despite this I believe that it is worth working to master the techniques that I showed. With respect to the previous reply to this thread you made - I agree that it is worth investing in high quality drills if factors such as the hole diameter are critical (as opposed to the rather loose requirement of 18-20 thou given in the original post) but I think it is unreasonable to condem any drill not made in the USA. It is worth looking at some of the manufactures who produce outstanding quality drills in countries such as Japan, Switzerland, the UK, Germany and France. Another point - I'm sure there are also some manufacturers in the USA who produce low quality drill bits too. As a watchmaker I'm sure you are aware that in the traditional approach to horological work, once drilled holes are often broached to size (again, by hand). This is going outside the scope of the original enquiry of course, but it is appropriate to remember that a twist drill will always produce a hole that is 1) Not circular, 2) Not where it should be, 3) Not straight - these three facts are an inevitable result of the twist drill construction and mode of operation - the trick (of course) is to make sure that the errors are small enough to be insignificant. Ian P.S. - Please feel free to vent off at me any time you like (as long as it doesn't interrupt your work too much of course!). Ian ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "n2562001" jlkiefferx~xxcharter.net Date: Tue Mar 8, 2011 2:38 pm ((PST)) Ian: My comments were not directed at you personally as pin vise drilling has been suggested many times on this board over the years. My comments were blunt and to the point as usual. More so probably because I am having a bad day correcting work that I suspect was done with pin vises and broaches. At any rate it sounds like you're not too torqued off so maybe I lucked out. In regard to drills, I suggested the highest quality available and added at least made in the USA only in the hope some may look at origin of manufacture. You are correct in that there are many sources of higher qaulity tooling including drills from Europe and Japan. My comments on drilling were made in reference to Horological drilling as mentioned. It is much easier to damage a valuable part than it is to correct damage. Life is short. I can see no value in taking the time to master methods other than those that have the highest track record of success. Where Micro drilling is still used, that method is spot drilling with leadscrew controlled drilling (Both manual and CNC) under Optical observation. It has been perfected in industry by dependably drilling millions of micro holes daily for decades. On the other hand I have personly never been able to drill a hole with a pin vise that I have been happy with. Nor have I ever seen one demonstrated to a standard I would accept for Horological restoration. Especially where small carbide drills are required to retain the original finish on expensive parts. While nothing is impossible, I am sure one can be drilled with this method that meets a standard, but I suspect it would require a great degree of skill. Again however, proven dependable industy micro drilling procedures can be mastered in a short time with minimal skills when using capable equipment. These same procedures were used and are used in the manufacture of horological movements. Again I can see no reason not to select a method that will allow you to do a full range of required drilling. Regular use of a sound procedure will assure a greater level of success required when working on valuable parts. I suspect we will have to agree to disagree on this subject not to mention taper broaching. But that's what makes life interesting. Jerry Kieffer ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "alenzx~xxbellsouth.net" Date: Tue Mar 8, 2011 8:48 pm ((PST)) In regard to Ian's vs. Jerry K's drilling methods. I'm familiar with (and use) both. My only lathe since the 50's (when I worked briefly as a watch repairman) was a standard watchmakers lathe. I only acquired a Sherline about 10 years ago. The problem I have with the Sherline is the tailstock ram deflection tolerance. I measure 0.001 in deflection at the end (approx .275 from the 0.00 mark) with the ram set to 0.00. Extend the ram to 1.00 inch and the deflection is 0.012. Add the length of the drill chuck and the length of the drill and it's sort of like trying to pin the tail on the donkey blindfolded . Is this considered excessive? Fire away. Al ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "n2562001" jlkiefferx~xxcharter.net Date: Wed Mar 9, 2011 9:36 am ((PST)) Al: I am always more than happy to comment if I am included in your request. However as always I will be blunt. If that offends anyone I apologize ahead of time. Micro drilling must be done on a regular basis to be understood. There are three main issues. Tailstock repeatability, alignment and drill movement control. I started out micro drilling on a watchmakers lathe equiped with collet holding tailstocks. However you quickly learn they are not created equal. Some are far better aligned than others. Since they are not adjustable, you need to try every lathe that you can until you find a good one. Once you find one that is aligned, you then need to lubricate the moving tailstock spindle with heavy oil. Anything movable will have deflection as you indicated on the Sherline. The heavy oil will center the spindle under the light loads of micro drilling. However the major problem I had with the watchmakers lathe was controled movement of the drill. While most spindles have micrometer depth control, they were not contollable in operation to the degree that I wished. At this point, I moved on to the Sherline Lathe for micro drilling. The Sherline of course is not without issues. First as it comes from the factory, tailstock aligment is not close enough for micro drilling. However, both headstock and tailstock are adjustable with P/N 1202 or P/N 1203. This is possible because Tailstock repeatability when moved is absolute on current production units. (Vertical locking screw.) If you have the horizontal locking screw, then it can be a crap shoot. Unless you have exact tension on the locking screw each time alignment will shift. All of my tailstock spindles are much tighter than yours, but I know that Sherline has tightened up that area in recent years. Might be worth a call to see if they have a fix. Once the Sherline was properly aligned, along with leadscrew control of drill movement, It has offered the greatest level of success. As an example that I think I have mentioned before. For many years I have done machining demonstrations with Sherline lathes at various Shows. (Sometimes others as well.) What I normally do is machine either .500" or .750" steel stock. It is normally machined down to a .010" pivot about .075"-.100" long in about 6 passes give or take. Then a .005" hole is center drilled in the end of the pivot with the whole process taking less than 90 seconds while being Observed by the public. Magnification is then provided for inspection. Samples are then passed out to anyone wishing one. I am sure someone on the board has seen this demo and or has a sample. Drilling is done with a spade drill that also doubles as a spot drill. At shows like this, I many times do not use my own lathe that has been aligned. In cases like this, .125" stock is mounted in the tailstock drill chuck. I then drill a hole in this stock using the headstock spindle sized to hold the drill shank. This gives drill alignment without doing lathe alignment since only one drill is being used. I would love to see anyone duplicate this demo with a Graver and Pin vise drilling. My next Show will be the NAMES show at the end of April. Anyone interested, could do the demo at a given time for public viewing and we can report back to the group. I can supply equipment including a .005" spade drill. (Bring your own Graver.) Contact me off list with your needs before the show. The demo capabilities mentioned above, I suspect will cover the require- ments of the average Sherline user. However they are far from the actual capabilities of the Sherline lathe. About a year ago or so, I had an equipment capabilities discussion with instructors at the NAWCC School of Horology. http://www.horology.edu/ As part of a demonstration, a random school Sherline lathe was selected. Using the method above a .07mm (.0028") staff pivot was cut. Then a .035mm (.0014") hole was drilled down the center of the pivot under tool mounted Microscope observation at 24x. My personal advice to beginners and students be it right or wrong is as follows. Life is very short. If you wish to develop a high degree of skill, do not waste time on procedures that have less than practical capabilities of quality equipment. Select sound proven procedures requiring the least amount of skill. If skill development is not an issue, then of course equipment/tooling/ procedure selection is of little concern. Jerry Kieffer ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "clarnibass" clarnibassx~xxyahoo.com Date: Wed Mar 9, 2011 1:38 am ((PST)) I'm far from an expert of machining, but with some of what I do in repairing musical instruments I need to drill small holes from about 0.30mm to 1.20mm (approx 0.012"-0.047") in brass, German silver and cupronickel materials. Both in round rods and sometimes in odd shaped objects. This is to fit "needle springs", these are springs that have needle shape (basically a very small diameter springy steel/stainless rod). The holes don't need to be super accurate, but a twist drill probably won't get a super accurate result anyway. A while ago someone gave me some suggestions. This person was a musical instrument repairer too but now for several decades is a specialist tool maker and expert machinist with a company to make musical instrument repair tools. So FWIW: "Drills any diameter from 0.30mm and up are a standard commodity. What does matter is that they are too flexible to START the hole. So chuck the tiny drill right on the flutes of the drill and make it into a tiny center drill to start the hole. If your chuck won't hold the drill, get a Micro Chuck, or perhaps use your micromotor.* Once you have the hole 1 diameter deep you can rechuck the drill bit longer and drill the rest of it without the drill wandering. Having the drill be flexible at this point is an advantage, as it helps keep it from snapping. Drilling small holes is easy once you slow down, take it easy and pay attention. You want each incremental stroke (called pecking) to be about 1/2 diameter of the drill... so it will be VERY SLOW work if you want the drill not to wander off center. Take your time and don't run very fast speed... ignore the theory that tells you to drill faster because of small diameter... the theory here is crap because the only thing that matters is keeping the drill flutes from packing." *This refers to that I'm sometimes using a dental micromotor for many things, including drilling holes free-hand, sometimes with 2.35mm shank drills. It can also hold micro chucks for holding regular drills. ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "Tom & Judy Bank" trbank1x~xxverizon.net Date: Wed Mar 9, 2011 6:57 am ((PST)) Gerald Goldberg wrote: > I have used a finger chuck for drilling small holes down to about > .012 in h13 or p20 .250 deep, it is not easy but do able. As long as we are talking about peck drilling, or at least clearing chips from a hole in process of drilling, the thing I seem to encounter is that if I don't clear the chips frequently enough they build up -- usually unevenly, and then even if they don't catch the drill and jamb or break it, they seem to push it off center, either diverting the path of the hole or enlarging it down inside the work piece. Is this right? Regards, Tom Bank Later message: I guess the [above message by clarnibass] speaks to what I was saying. Regards, Tom Bank ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "Pete & Pam Boorum" smallifex~xxmyfairpoint.net Date: Thu Mar 10, 2011 7:09 pm ((PST)) Hi, I need help. Have been reading about micro drilling which is pertinent because I need to drill 8 radial #74 holes for spokes in each end of a .0875" diameter hub for the wheels used in a 1970 vintage garden cart. Need to make at least five carts or ten hubs. Have done this job several times before but this time the drills are snapping off right at the entrance to the hole destroying the part, because the drill will not come out. The hubs are turned in sequence along a 3/16" brass bar with a flange .070" thick on each end this is where the spoke holes are drilled. Heeding Jerry K.'s advise I spotted all the holes. The length of 4 hubs are chucked with a 3 jaw chuck in the Sherline rotary table held vertically with an angle plate. The tail end of the part strip is supported with a tailstock so it is quite rigid. The spotting went well, then I tried to drill down about .030" which is enough to capture the piano wire spokes for lead soldering. There is a new photo of the set up http://groups.yahoo.com/group/sherline/photos/recent/list This is where the drills break. Tried a high speed, a low speed, a fine drilling attachment, the lead screw and even removed the part and used a drill press. I had three different brands of drill, one American. The result was fairly similar with all the methods. I would peck and drill and this would work for two to 8 holes and the drill would break at the entry point where the drill meets the brass. Have not used oil or lubricant. Should I with brass? This is probably K &S brass. Why is it grabbing and breaking the drill occasionally? Any help would be appreciated. Running out of drills as well as patience. (Actually made some hubs out of hard maple this afternoon.) Pete Pam & Pete Boorum, Smaller Than Life IGMA Artisans 79 Sebbins Pond Drive, Bedford, NH 03110 http://www.smallerthanlife.com ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "JERRY G" chieftoolmakerx~xxearthlink.net Date: Thu Mar 10, 2011 7:41 pm ((PST)) Hi Pete, Quick questions..... # 74 is .0225", right? Have you checked the runout of the drill in the chuck? Can you get any spade drills that size? Ever hear of drills? or< Titex>? Best to get drills with a standard shank and run them in a collet, or WW collets with an adapter you can skin to run "Dead Nuts". Brass likes a scraping action. Get a jewelers loupe and (gently) stone a very slight flat on the cutting edges. Just enough to see a shine. Might stop the grabbing. Later, Jerry G (Glickstein) ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "n2562001" jlkiefferx~xxcharter.net Date: Thu Mar 10, 2011 8:38 pm ((PST)) Pete: Several things. First, Jerry G is correct in that a drill chuck will normally have too much runout for a #74 Drill. WW Collets are best for micro drilling as Jerry G suggested. However if you do not have them and do not want to purchase them you can also make up a simple accurate holder. Take a #1 MT adaptor and spot drill/drill a centered hole in the end while held in the lathe spindle. The hole should be friction fit for your #74 drill or can be held in place with loctite. This process will assure minimal runout if properly done. Then transfer the arbor to the Mill. Once you have spotted your holes, they MUST be returned to the exact spotting position. In addition, if you have too much drill chuck runout, drills will snap almost instantly when they hit the spot. They will also snap if you enter the spot too fast. You can try positioning the tip of the drill in the spot AND THEN TURN ON THE MILL. Assuming none of this is a problem, I would suspect a couple more issues. First would be drill quality even though you said some of the drills were USA made. Second, always use cutting fluid when drilling metals. Third, if your drills were purchased at hobby supply sources, I would be willing to bet you have carbon drills. Carbon drills will easily snap as you mentioned as you start to drill. Especially poor quality carbon drills. Quality Carbon drills have their place, but this is not one of them. I would suggest Quality High Speed Steel Drills from any reputable machine tool supply house. .030" deep is not that deep and you should be able to easily drill brass to this depth without issue. Assuming you are drilling brass. If by accident you are trying to drill Brazing Rod that looks like brass, then you are in deep trouble. Jerry Kieffer ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "Tom & Judy Bank" trbank1x~xxverizon.net Date: Fri Mar 11, 2011 7:07 am ((PST)) Pete: First off, K&S brass has a reputation for not being the best stuff to machine. I don't know what alloy it is, but it is said to be better for bending than for machining. That aside, I have used it, and have drilled small holes in it for model railroad models. The thing I see in your setup (pictured) is that you have a skinny rod which has been turned to reduce the diameter quite a bit and repeatedly. You may have a certain amount of flex, like a lot of flex in comparison to the .o875" drill diameter. I would make a support with a "V" notch in one end that would just fit under the work and could be positioned to counter the pressure of the drill coming down. Or, you might have better luck drilling the holes first and then doing your turning; but that would mean extra work finding and clearing the tiny holes. Hope this helps, I understand frustration! Tom Bank ------- Re: Drill holes in .031 Brass Square. How to keep the drill from wal Posted by: "Pete & Pam Boorum" smallifex~xxmyfairpoint.net Date: Fri Mar 11, 2011 7:28 pm ((PST)) Hi. Thanks to everyone for their help drilling the brass with the #74 drill. Got 128 holes drilled today without breaking a drill once I figured it out. Took the Chief's advise and indicated the drill in the Jacobs chuck. The Sherline fine attachment with the spring loaded quill was the worst with TIR of .006". The regular chuck was a little better. Then I took Jerry K's advice and made a #74 drill holder out of a blank Sherline WW collet. A #75 drill made too big a hole so I went with #76 for .020". This gave a slide fit but I used it with a TIR of about .001". Didn't have any Loctite so I tried CA glue which worked well enough. Actually, the one time I slipped and fed too much, the drill grabbed and the Super Glue let go saving the day. The drill I am using came from Enco and is HSS and US made. We only use the imported drills on wood and avoid carbon drills completely. Somewhere, I think it was in Joe Martin's book, but I can't find the reference, I read that you machine brass dry without a lubricant. For some reason I extrapolated this to drilling which turned out to be the biggest problem. Tapping oil made all the difference as long as I only peck about 1/2 the diameter of the drill before relieving the chips. I also tried the Chief's suggestion of re-sharpening the flutes with a stone. I did this at the end after I had run the drill into a hole with a broken-off drill in it. Figured that re-sharpening couldn't hurt it any more. With the high powered magnification this was awkward but it did cut very slowly and did not grab. I took Tom's advise and shortened the length of the rod to reduce deflection. But, most importantly, I took Dan's lead and asked questions recognizing the point that I know nothing. I also just put the new DE-1043 license plates on my van so Dan, I am now officially a target. (A little navy humor.) Thank you all again. The lady who makes scale plants in California will get her two garden carts and we will get at least a couple back into stock. Pete Pam & Pete Boorum, Smaller Than Life IGMA Artisans 79 Sebbins Pond Drive, Bedford, NH 03110 http://www.smallerthanlife.com ------- Re: Drill doctor??-Is it any good?? [atlas_craftsman] Posted by: "Starlight Tool Services Ltd" starlight_toolsx~xxtelus.net Date: Sun Mar 20, 2011 9:05 pm ((PDT)) Well I use my Darex XT3000 to sharpen not only my own bits, but also clients' bits and I wanted a system that I could guarantee good results from. I did not feel good about freehand sharpening clients bits as even though I am not bad, it is hard to get it "just perfect" by hand, more than adequate for own shop use, but not to hand to a client. They have a model under the XT3000 that is rated well, but not for the high quantity of bits and then they have a fully automatic CNC version that needs a mortgage to get. If anybody is from Canada and needs a Darex, we are a dealer for them and will get you a good price on the unit or on any of the parts and pieces for them. Walter ------- Re: Drill doctor??-Is it any good?? Posted by: "Glenn N" sleykinx~xxcharter.net Date: Sun Mar 20, 2011 9:30 pm ((PDT)) That may be, I haven't used up the grinding wheel yet, and I have only had it about 8 years. I also use 135* split point for most of my bits. I have had to take the collet apart and clean the grit out of it. I don't even try to make them "spark out", and only take about 4 or 5 turns before I reset the bit in the collet. I sometimes use a big magic marker to mark the lips and margins so I can see what is being ground and also when I am testing a just ground bit to be sure I got the relief I wanted. It has ground enough bits to pay for itself so if it gets sloppy I will toss it and buy another. :) I am also only about 20 miles from the DD factory so getting some assistance should be easy. Glenn ------- Re: Drill doctor??-Is it any good?? Posted by: "David Beierl" dbeierlx~xxattglobal.net Date: Sun Mar 20, 2011 10:17 pm ((PDT)) At 12:02 AM 3/21/2011, Starlight Tool Services Ltd wrote: >They have a model under the XT3000 that is rated well, but not for >the high quantity of bits and then they have a fully automatic CNC >version that needs a mortgage to get. The "light duty, intermittent use" V390 lists for $USD1500. It's essentially a somewhat fancier metal Drill Doctor, with much more reliable point splitting and an extra control for how much material to take off the end of the drill. It still uses the same drill alignment method, and you still have to use it correctly and consistently to get good results. Obviously the Drill Doctor was built to a price, just as the Atlas lathe was. Yes, you have to baby it - the manual says that the harder you work at keeping the grit out of the chucks, sockets etc, the longer it will work for you. Actually the video on the V390 says more or less the same thing. But buying a drill sharpener that costs up to two or three times* what our lathe did seems as out of proportion as some of the scraping discussion that was going on recently. YMMV. *referring to the XT3000 here as well Yours, David Beierl -- Providence RI USA Atlas 618 6"/3/index.html" lathe ca. 1941, shiny-new Taig mill. ------- Re: Drill doctor??-Is it any good?? Posted by: "Glenn N" sleykinx~xxcharter.net Date: Sun Mar 20, 2011 10:43 am ((PDT)) You would have had much better luck had you read and followed the instructions. My DD works great and I get consistant results. I have been sharpening drill bits by hand for 40+ years and I still do sharpen by hand for the larger bits or if I need a special grind for brass or such. For most of the bits the DD gets to do the job. You do need to rough in a broken bit first and if the outer edges of the lips are chipped you need to grind the point down just enough to let it cut deep enough to clean up the lips. You also have to re set the bit in the collett several times for really bad bits as the point gets ground away and it moves up the helix. A very light touch is required to let it follow all the cams and for splitting the point. ------- Re: Drill doctor??-Is it any good?? Posted by: "Doc" n8as1x~xxaol.com docn8as Date: Sun Mar 20, 2011 2:28 pm ((PDT)) > Yup cost way more than the 750 which I sent back within days of getting it as I could sharpen better and faster by hand than it would produce! Walter < amen ...no correct collets, no set ups,......will hand ground drill be as true to size ? depends upon your skill & desire & time spent ....will it drill as many holes before dull, again same answer as first ...... BUT i & many others can sharpen a bit in 5 sec or less ...so if the rake angle is too much, & it wears too quickly., it still DRILLS ....& in 5 sec, it's sharp again... if the angle is 100deg or 125 deg, i dont care .....it still drills .. & again 5 sec. sharpens ..industrial practices are in many cases unecessary & attempts to emulate, complicate the life of a HSM ... re size ...drill bits drill various amts of oversize ..if your hand grounds have one lip longer ( that you didnt notice) & you want the hole w/in NORMAL tolerance, drill 1/64 under first....cause the FIXED centering is lost, it will be w/in normal limits ... if you radius the edges of the flutes & previously use a 1/64 under bit, it will ream VERY close to the size of the bit .. Burghard's machine tool operation vol 1 has the info ( $10 used ) ... if you want private instruction, come to so. ky for an afternoon & i will instruct gratis, i sharpen left handed, so i found out from burghardt,..although i am right handed .......just learned that way more than 60 yrs ago .... best wishes docn8as ------- Re: Drill doctor??-Is it any good?? Posted by: "Rick Sparber" rgsparberx~xxaol.com Date: Sun Mar 20, 2011 9:53 am ((PDT)) Since I was not there, it is impossible for me to say why you got poor results. It might have been the machine or might have been technique. All I know is I get great results every time I set up the machine correctly and get terrible results when I do something wrong. My guess is that you would get an off-center result if the drill was not properly aligned by the spring fingers before the collet was tightened. Those spring fingers are very unforgiving. If you jam the drill into the hole and bend a finger, game over. The fingers would need to be replaced. Rick ------- Re: Drill doctor??-Is it any good?? Posted by: "L. Garlinghouse" lhghousex~xxsuddenlink.net Date: Mon Mar 21, 2011 4:44 am ((PDT)) RE: The "What to do with some worn out drills" sub-thread. I second Jon's suggestion that you learn to sharpen drills by hand. It is a useful skill and not too difficult. Some suggestions: If you cup your hand around the drill point so you have a sort of tunnel to sight thru and hold it up to the light, you can see a clear silohuette of the point. Turning the drill you should be able to get and idea if both cutting edges are the same length. The proof of the pudding is that when you drill a hole 2 equal size chips should come off each cutting edge. Easiest if you start on drills that are not too small -- I'm guessing your brake rotor casualties are probably 1/4" + -- that would be a good size to learn on. Also they need to be long enough to get a good grip on. Read up on drill geometry. The 135 degree included angle can be thought of as 45 degrees past a 90. Easier to get a mental picture of how it should look. I saw an Argentine machinist sharpen a 1/16" drill and not even check it out and then drill a perfect hole with 2 equal sized chips coming out of the hole. So like Jon's friend, hand sharpening drills can be mastered and drills sharpened very quickly. I've no experience with a Drill Doctor, but will probably use a neighbor's DD shortly for some very small drills and some center drills, ones I can't get a good grip on. Have fun!! L.H. Garlinghouse Arkansas USA ------- Re: Drill doctor??-Is it any good?? Posted by: "Lee Miller" goto.lee.1stx~xxgmail.com Date: Mon Mar 21, 2011 7:27 am ((PDT)) Jeff, I have a Drill Doctor that I have used for years and I am very happy with it. It makes resharpening drill bits as easy as 1, 2 3. I had a similar event drilling stainless and learned a neet trick that works very well. Use cobalt drill bits, vinegar as the coolant and drill as fast as the bit will cut. If the stainless get hot, it hardens and your drill bit is history. I have used this technique ever since an old timer suggested it and it works great. Good luck! Lee ------- Re: Drill doctor??-Is it any good?? Posted by: "Doc" n8as1x~xxaol.com docn8as Date: Mon Mar 21, 2011 7:41 pm ((PDT)) Lautard's bedside reader has prints of a sharpening jig for 1/8 & under drills ...essentially provides a FLAT rake by running it across a stone ....it does work & the flat rake does not appear to be a problem ....as ususal, aligning the drill flutes is critical saw another suggestion at one time that very small drills hand sharpen better by raising the rear UP rather than DOWN ..i tried a few that way & he may be correct, as he was about a lot of other things.....certainly wud help to have young eyes once again best wishes docn8as ------- Re: Drill doctor??-Is it any good?? Posted by: "tyleryoungblood" tyleryoungbloodx~xxyahoo.com Date: Mon Mar 21, 2011 11:34 pm ((PDT)) Nice timing on the question. Barry and I just finished reviewing the Darex V390 and the Drill Doctor 750x. We also just shot a video tutorial on how to sharpen drill bits by hand. Here's the link to the video. It's broken into two parts, but it's worth the time to view if you've never seen how this is done. Barry is a master machinist and a machining instructor at the local technical college, so he does a great job explaining the hand sharpening process. Video Tutorial - How to Sharpen Drill Bits By Hand http://www.projectsinmetal.com/video-sharpening-twist-drills-by-hand-a-\ 2-part-video-tutorial/ Back to the Darex vs the Drill Doctor. Both produced a far better point than two different master machinists could produce by hand. And they far exceeded my novice drill sharpening abilities. And I'm serious about this. We used an optical comparator to look at the points of a hand sharpened drill, a Drill Doctor drill, and a Darex drill and both machines beat the hand sharpened by a mile. However, comparing the two isn't really fair because they are for two completely different markets. It's like a luxury sports car vs a honda. Both get you there, but one has a better fit and finish (the Darex). The Drill Doctor feels a bit plasticky, but if you follow the directions and keep it clean (blow the grit out) it will work well for the home hobby machinist. The Darex is excellent, it's just too pricy for most home shop machinists. It's more for a small to medium sized shop that needs to sharpen 50-100 drills a week. We only tested the 750x, so I can't speak to the quality of the other Drill Doctor models, but the 750x is great for the home enthusiast who needs to sharpen an occasional drill. And one other thing that I know is important to a lot of you. Darex and Drill Doctor are by the same company and the company is based in Ashland Oregon. American Made. We shot a review video of the Darex also, but it's still being edited. If you guys are interested I can post a link when it's done in a few days. And no, I don't work for them. I'm just really pleased with the machines. ------- Re: Drill doctor?? minimum size drill Posted by: "jerdalx~xxsbcglobal.net" jtiers Date: Tue Mar 22, 2011 5:36 am ((PDT)) > I was curious what the smallest bit you tried was, > and if you did a split point. I'd be interested if they could > handle #40 drills in a split point. Jim Ash The DD actually is not intended for small drills. The collets will not hold them, and likely the precision of the plastic parts is far less than is required to do a repeatable good job on small drills, where a small error may result in a drill with only one lip. I'd have to go find where I stuck my old DD and read the directions again, but the size is somewhere around 1/8" that is the smallest recommended size to sharpen with it. After mine wore out (maybe 100 drills sharpened), it would not sharpen a 0.187 or 0.203 drill decently, but would still work acceptably with a 5/16" or larger drill. The errors due to the inherent manufacturing tolerance slop, or the slop that wear will soon create, do affect the minimum usable size, which goes up with wear. You have almost NO CHANCE of sharpening a #40 split point drill with it. The split point facility on a DD is totally incapable of reliably doing what they call a split point on small drills; the slop may be similar to the diameter of a #40 drill. If you rarely sharpen drills the DD will last and work. I suspect that I simply have too much sharpening work for a DD. When I pulled mine out, I usually sharpened at least 5 and often 10 or more drills before putting it back on the shelf. It is not made for that sort of usage. JT ------- Re: Drill doctor??-Is it any good?? Posted by: "tyleryoungblood" tyleryoungbloodx~xxyahoo.com Date: Tue Mar 22, 2011 8:32 am ((PDT)) The Darex will sharpen as small as an 1/8th inch. And it worked well for all the sizes we tested (1/8-3/4) and could split the point on all sizes. The depth of the point splitting feature on the Darex is adjustable, it's more by feel with the Drill DR, but still easy to do. I think they never made a chuck for the smaller sizes because the drills themselves are inexpensive enough to replace rather than resharpen, even when they are exotic materials such as carbide or cobalt. I'm not sure on the smallest size for the Drill Doctor, but my hunch is that it is similar (around 1/8) and that's because the chucks are very similar in design between the Darex and Drill DR - except the Drill DR has a plastic chuck while the Darex has stainless. Tyler Youngblood ProjectsInMetal.com ------- Re: Drill doctor??-Is it any good?? Posted by: "Starlight Tool Services Ltd" starlight_toolsx~xxtelus.net Date: Tue Mar 22, 2011 11:56 am ((PDT)) The Darex XT3000 has an optional chuck that will sharpen from 1.5 - 7.0 mm (0.059 - 0.276") It comes with a finer stone 360 Gr CBN for HSS or a 360 Gr diamond for Carbide. Walter ------- Re: Drill doctor??-Is it any good?? Posted by: "jerdalx~xxsbcglobal.net" jtiers Date: Tue Mar 22, 2011 8:22 pm ((PDT)) > The depth of the point splitting feature on the Darex is > adjustable, it's more by feel with the Drill DR, but still easy to do. LOL.... "by feel".... yeah, easy to go too far, or just barely not far enough, where you really can't take off any more by another blind swing into the wheel without risking the point. Works OK on a 0.75" diameter drill if you are not too fussy.... An "un-needed feature", the lesson being "do it right and make it work easily and reliably, or don't put on the feature at all.". They would have been far better off to use the saved money to make the alignment gizmo out of something else more sturdy than the metal pallet strapping they cut off their incoming shipments. JT ------- Re: Drill doctor??-Is it any good?? Posted by: "JeffD" jefdaviesx~xxsbcglobal.net Date: Tue Mar 22, 2011 9:41 pm ((PDT)) I want to THANK all of the gentlemen on this group for all the trouble you took in response to my question. I did buy a 750 , and despite that it is not heavy duty things of the past that we love, it has been very effective considering the relatively small cost. Maybe by the time it wears out, I could see how I could sharpen free hand, but for now, I will leave that to the hugely skilled machinists of old. Kindest regards, Jeff Davies, North California ------- Date: Tue, 5 Apr 2011 16:21:27 +1000 From: "John Manners" Subject: Re: [OldTools] Long hole boring - was Re: New knife done(ish) Tom Conroy writes: "On a finishing tool handle, though, I can drill into the 3/4" x 7" handle for about half an inch with an eggbeater drill, then turn the drill so that the workpiece is upward and turn the crank without holding the workpiece. If the hole is not straight (it never starts straight) the far end of the workpiece will make a little circle in the air and I can see from that how much it is off and (at the moment when I stop cranking) in which direction. This lets me grab the workpiece and gently lever it over toward straight as I turn the crank. Do this 2 or 3 times for a two-inch-deep hole and it will be pretty good. Especially since you "burn in" finishing tools into their handles, and you can very substantially correct the straightness as you are burning in (or, for that matter, you can ruin the straightness). Its good enough for what I need. Good enough for government work. Good enough for jazz. Good enough for book arts." Thanks, Tom, for a very useful and practical wheeze. Ray Gardiner writes: "D bits can be ground from drill rod stock, so that they cut on the edges and self center. Most of these require a starter hole drilled with a twist drill." D bits are remarkably accurate, so much so that they will refuse to be shaken from faithfully following the path of any "out" in the starter hole which should be to the depth of at least one-half of the diameter of the drill. Although I have done very little turning I suppose that the possibility of running a little out affords a good reason for boring the hole whilst the piece remains unturned and then turning it along the axis of the hole. Tapered centres, the appropriate one with a driving spur, should be sufficient to align the piece along its hole. The customary relief at the "D" cutting end is 5 deg. in both directions although this angle can be increased a bit for boring wood. The ground-out section of the wire should stop a little short of its full diameter to avoid oversize holes and to permit stoning the longitudinal face to form good, sharp side-edges. The drills for use with wood can be made from a type of very hard "wire" which is available cheaply in a variety of gauges or diameters and usually the supplier has the equipment to straighten lengths of it perfectly. The "wire" does not need to be tempered. I have used these drills to bore long holes in timber where the length was beyond the reach of a standard "long" drill bit of the required diameter and where the hole was too small to permit the using of a bit-extender. Although a micrometer may inform that the wire's section is slightly oval this creates no real problem with wood-boring. Regards from Brisbane, John Manners ------- holding small drills [sherline] Posted by: "Pat B" patbutlerx~xxcomcast.net Date: Wed Apr 20, 2011 11:39 am ((PDT)) I have a project where I'll need to drill some small holes around the #60 size. Not sure yet if I'll use the lathe or the milling attachment to the lathe. What is the best way to hold a small drill bit like that? I under- stand that the chuck probably has too much runout, yet I don't see collets available in all the sizes that would accomodate these small drills. There are some inexpensive micro drill bit holders that get chucked into the Jacobs chuck and they seem to be very low quality. Any ideas? Pat ------- Re: holding small drills Posted by: "Fox Charles" cafox513x~xxverizon.net Date: Wed Apr 20, 2011 11:56 am ((PDT)) COLLET! And check Sherline for their set -- though I can't afford the whole set for my hobby work. Better: ask Sherline which one they would recommend for each application, then order two or three. I just had the lovely discovery that my tiny endmills are fat enough so I can use an existing collet from my set of three. I don't have to drop $40 (or less) plus shipping. Ahhh. Charles Fox ------- Re: holding small drills Posted by: "Flosi" flosigudx~xxsimnet.is Date: Wed Apr 20, 2011 12:04 pm ((PDT)) Get a drill with wider shank and use standard milling collet. rgds, Flosi ------- Re: holding small drills Posted by: "Pat B" patbutlerx~xxcomcast.net Date: Wed Apr 20, 2011 12:54 pm ((PDT)) Do you know who sells those? All of my smaller drill bits have a shank size that is the same size as the drill itself. ------- Re: holding small drills Posted by: "Jeffrey T. Birt" birt_jx~xxsoigeneris.com Date: Wed Apr 20, 2011 1:01 pm ((PDT)) If you get carbide micro drills they will usually have a 1/8" shank, so you can use a standard collet or end mill holder. All the micro drills I carry have 1/8" shanks: http://www.soigeneris.com/Carbide_Micro_Drill_Bits-list.aspx (warning shameless self-promotion.) Jeff Birt Soigeneris.com ------- Re: holding small drills Posted by: "Pat B" patbutlerx~xxcomcast.net Date: Wed Apr 20, 2011 1:02 pm ((PDT)) I have their smaller collet set but was under the impression that the gripping range was rather small and that it might not always be possible to find a collet for each drill bit I'd like to use. ------- Re: holding small drills Posted by: "DA Dossin" danatlx~xxyahoo.com Date: Wed Apr 20, 2011 3:18 pm ((PDT)) The Sherline collets go down to 1/64 inch. DanD. ------- Re: holding small drills Posted by: "Thomas A Trikalinos" ttrikalinx~xxgmail.com Date: Wed Apr 20, 2011 1:05 pm ((PDT)) Flosi's solution is the one I use. I often use up to #83 drill bits -- carbide on a 1/8 shank. Ebay has many of these for as cheap as $5 per dozen. Horrible Fright has random assortments of 12 small drills for $5 each. I've bought a bunch -- they do the work and are cheap enuf. take care, tom in MA ------- Re: holding small drills Posted by: "Mitchell L. Oldham" mitch_oldhamx~xxhotmail.com Date: Wed Apr 20, 2011 2:30 pm ((PDT)) This is a good reason to use or have an ER 16 or ER 25 chuck on hand. The ER 16 set I had back in the Unimat days would have handled this problem. Mitch Oldham ------- Re: holding small drills Posted by: "Pat B" patbutlerx~xxcomcast.net Date: Wed Apr 20, 2011 3:32 pm ((PDT)) Thanks for all the ideas. Looks like my best best is to find these tiny drills with larger shanks then buy the appropriate collet(s) to fit. Pat ------- Drilling Angled Holes [myfordlathes] Posted by: "Barry" 2barryforrestx~xxtiscali.co.uk Date: Sun Sep 4, 2011 2:43 am ((PDT)) Can someone please advise me on an easy and hopefully fairly accurate way to drill a hole at an angle to a face, i.e. not at 90 degrees to the surface, and still follow the required direction through the material without going off centre / off the required line? For example when drilling steam passages from a steam/valve chest housing diagonally towards the cylinder ends. So far I have achieved reasonable accuracy by centre punching slightly "off-side", starting a small "dimple using the tip of a Centre Drill, then setting the workpiece at the appropriate angle and using the dimple as the centre of the hole. While it has achieved the desired result it somehow it doesn't feel as though this would be the "preferred" way to do it. Thanks Barry ------- Re: Drilling Angled Holes Posted by: "Andrew Curl" methuselahx~xxntlworld.com Date: Sun Sep 4, 2011 4:09 am ((PDT)) If you can, start the hole with an endmill (FC3) those things don't mind being on [an angle] at all. Follow that up with the standard centre drill, pilot drill procedure. Andrew ------- Re: Drilling Angled Holes Posted by: "Rich Dean" toolman8x~xxcopper.net Date: Sun Sep 4, 2011 7:53 am ((PDT)) Barry, spot face with an endmill close to the drill diameter, centre drill (spot drill) then drill. RichD ------- Re: Drilling Angled Holes Posted by: "mwalsx~xxtiscali.co.uk" mwalsx~xxtiscali.co.uk Date: Sun Sep 4, 2011 7:39 am ((PDT)) One way depending on the size of the work to be drilled is to clamp it onto the swivelling vertical slide if you have one, then you can drill the hole at any angle. I have done cylinder ports this way before quite accurately. Best Wishes Martin ------- Re: Drilling Angled Holes Posted by: "Yi Yao" yix~xxyyao.ca u_umlaut Date: Sun Sep 4, 2011 8:35 am ((PDT)) I do the following when I can: 1 - Chuck the piece into a lathe at the correct angle so that drilling with the tail stock will produce the correct hole 2 - Face the surface that I am making the the hole in (if possible) 3 - If I can't perform a facing cut, an endmill chucked in the tailstock could produce a sufficiently flat surface as well (go slow) 4 - Spot drill now that the face is flat 5 - Drill as you ordinarily would Cheers, Yi ------- Re: Drilling Angled Holes Posted by: "Kevin" tadpolex~xxbtinternet.com Date: Sun Sep 4, 2011 9:57 am ((PDT)) There are really two problems here .... getting the angle correct and then starting the drill on the sloping face. The second problem has already been addressed by others .. essentially get rid of the slope locally by using an end mill. The first problem hasn't though ... how to get it at the right angle so that, having started it in the right place it will come out where wanted. Often lining things up by eye will be good enough, aided where necessary by lining up visually against a drilling machine column, or a suitable square, or part of the lathe bed or whatever. Another way, that I've read about but never tried, for the drilling machine, is to make up a little jig. It consists essentially of two pointers ... imagine a short pointed rod held in the drill chuck. Fixed to this somehow is a side arm that projects out sideways, then down, then turns horizontal again and supports a second pointed rod that points upwards and exactly in line with the first rod. Now when clamping the workpiece you obviously arrange it so the the upper rod touched the entry point for the drill and the lower point touches the exit. As I say, haven't tried it myself. Tubal Cain, always worth paying attention to, showed in one of the Workshop Practice books, a simple wood wedge which supported a cylinder block at the correct angle, which was then presumably clamped before drilling. You'd derive the angle from the drawing. If the drill will exit onto an angled surface then be extra careful as it comes out. If you want to put an angled hole through a piece of round stock, say to make an angled boring bar, it can sometimes be useful to make up a jig to guide the drill. Drill/bore a hole axially through a piece of round or square stock to accomodate the boring bar, and provide it with a cross hole drilled and tapped to take a securing screw. Mill a flat across one end and drill from that flat right into the central hole. Put the workpiece in place, secure with the screw and drill away, choosing the drill depth so that you go through the workpiece and into the jig material on the other side slightly. Kevin NW England, UK ------- Re: Drilling Angled Holes Posted by: "Barry Forrest" 2barryforrestx~xxtiscali.co.uk Date: Mon Sep 5, 2011 6:37 am ((PDT)) Thanks to all those who replied to my question by suggesting the use of an end-mill to produce a flat spot (thus removing the angle) into which the centre-drill or drill bit can by started. Barry ------- [Drilling and reaming a precise and round hole] Re: 1/4 finishing [taigtools] Posted by: "Steve Blackmore" stevex~xxpilotltd.net Date: Tue Sep 6, 2011 3:44 pm ((PDT)) On Tue, 06 Sep 2011, you wrote: > I am curious about the answer also. Someone long ago told me the practical max undersize was about 0.005" diameter for the drill hole that would be subsequently reamed. That being said, I sometimes have a heck of a time making a very circular hole (not egg shaped or three sized) such that it leaves enough material all the way around the hole such that there is something to ream out. I guess it depends on having carefully sharpened drill bits and pilot holes and lubricant. Any comments from the experts on making high quality, circular drill holes, much appreciated. < Lots of thing cause triangular holes. Other than what you have already mentioned, feeding too hard/wrong relief angle, poor spindle rigidity, crap chuck or crap drills :) Always clamp work properly, hand holding apart from being dangerous, produces crap holes. Use stub drills wherever possible. For thin material use 135 degree drills, preferably split point. Three flute drills generally produce tri lobed holes, two flute drills, oval holes :) Always drill a pilot hole first where practical. If the "point" of the drill is not cutting the drill will track better and produce a rounder hole. BUT - No matter how hard you try you will never drill a perfectly circular hole with a standard drill bit. Steve Blackmore ------- [Drilling in cast iron] Re: test for post publish ??? [shopbuilttools] Posted by: "gdnichols" gdnicholsx~xxaol.com Date: Sun Oct 2, 2011 9:48 am ((PDT)) On Sun, Oct 2, 2011, Ed Sarlls wrote: > Why are you up so late? As a woodworker, I don't have the need to bore large holes in iron very often, but this week I need to bore 5 x 7/16" holes into the cast iron skirt of a saw table wing (A. I'm attaching a 10" x 27" CI router table wing on the right of the existing wing on a Jet 10" sliding table saw. http://www.amazon.com/gp/product/B000KILH0E Unless someone else has a better idea, I'm planning on step drilling the holes -- maybe in increments of 1/16 something like 1/8, 3/16, 1/4, 5/16 ...etc, etc. I'll probably lubricate with motor oil. The two holes in the wing can be drilled at the drill press but the three holes i the existing saw table wing will have to be drilled with the saw on the floor -- maybe using a chain and a crowbar with a hand drill. I guess I could rent a proper drill if that was absolutely necessary, but I'd rather do it with existing equipment. This router wing only cost $119 on Amazon and is all cast iron except for two 4" steel rings to re-size the bit hole. Rather than the rectangular plate most router tables use nowadays, this one has four adjustable clamps which slide in tracks cast into the bottom. Seems like it will work well for my limited needs. I'll try to post a few photos as the work progresses. Dale ------- Re: test for post publish ??? Posted by: "Jason Beam" beamerx~xxbeamerweb.com Date: Sun Oct 2, 2011 9:56 am ((PDT)) Cast iron needs no lube - in fact, you SHOULD do it dry. You can easily drill it by hand if you pay close attention to squareness. And stepping is a good dea - 1/16" increments my be a little bit grabby, though. When I drilled my iron, I went in 1/8" increments. Jason Beam Sacramento, CA ------- Re: test for post publish ??? Posted by: "Rob Van der Star" rvds1305x~xxgmail.com Date: Sun Oct 2, 2011 9:59 am ((PDT)) You don't use lubricant on cast iron, it has graphite in it and will produce powder as swarf. I would make a dimple with a punch then drill 1/4. After making sure all the holes are properly centered, open them up to 7/16 in one go, it is not hard to drill. Assuming you don't have a drillpress (I can't imagine why) you should use a brand new drill bit so that the two flutes cut equally making it less prone to skate. Rob ------- Re: test for post publish ??? Posted by: "kabowersx~xxNorthState.net" Date: Sun Oct 2, 2011 10:13 am ((PDT)) Be especially careful as you get almost through. That's where you hit the second area of hard surface; wonderful place to break a bit 8=( One trick I use is to set the torque limit on a bad drill bit just heavy enough to spin the bit. Keith Bowers WB4LSJ - Thomasville, NC ------- Re: test for post publish ??? Posted by: "Ray Kornele" krazykyngekornyx~xxgmail.com Date: Sun Oct 2, 2011 2:27 pm ((PDT)) Cast iron is easy to drill, but, it wears out drills like crazy. It produces fine powder that is highly abrasive. KrazyKyngeKorny (Krazy, not stupid) ------- Date: Sat, 01 Oct 2011 22:04:17 -0400 From: Charlie Rodgers Subject: [OldTools] The Versatile Brace Since things are slow on the list, I'll slip this in just to see if things are still working. So there I was, trying to keep SWMBO happy by installing the glass shower door she decided she must have for her bathtub. The jambs wound up positioned over ceramic tiles and had to be attached with screws into plastic anchors. I marked the tiles by coating the butt end of a small twist drill with a felt pen (Sharpie, if it matters) and touching it to the masking tape I'd placed on the tile behind the jambs. I then made a very small indenation in the tile by lighting tapping a 3/8" (I dunno the metric size, Jeff) masonry bit on the spot with a hammer. Never one to miss a chance to use an old tool, I stuck the masonry bit in a brace. I reckon a lot of you have done it, but it was the first time I'd tried it. I've never made a neater hole with a masonry bit. It was a perfect fit for the the screw anchors. No muss, no fuss, no noise and no tail. Next up, glass doors on the shower stall. Charlie Rodgers Clinton, Maryland ------- Date: Sun, 2 Oct 2011 08:25:23 -0400 From: Darrell & Kathy Subject: Re: [OldTools] The Versatile Brace Not in a brace, but I have cut holes in tile using a hand drill. Don't forget to sharpen those masonry bits! One of those cheap diamond stones will do the job nicely, and your bit will cut much faster. What am I so surprised that a tool works better after sharpening it? You'd think I would understand this by now. Darrell LaRue Oakville ON Wood Hoarder, Blade Sharpener, and Occasional Tool User ------- NOTE TO FILE: See, another reason to have a manual drill. Better yet, an antique manual drill. Better yet, several of different sizes and/or designs and/or by different makers. You do own more than one bit, right? ------- Drill bit & countersink angle questions [sherline] Posted by: "Alan" alanhyx~xxlive.com Date: Tue Oct 4, 2011 9:02 am ((PDT)) I've been going through the latest Enco flier and finally realized that I have a serious confusion. I have bought "jobber length" drill bits in the past. These appear to have a "standard" tip angle of 118 degrees. In the flier, I see drill bits with either a 118 or 135 degree tip angle. I assume that this is the angle measured between the two sides of the tip. i.e. an angle of 180 degrees would be similar to a standard flat end mill. Now, they don't list any "spotting drills" in the flier, but do list "drill point" end mills. These are listed with an angle of 90 degrees. They also have the usual "combined drills and countersinks" with angles of 60, 82, and 90 degrees as well as countersinks with these angles. It seems that I have many questions about all of these angles: 1) If I spot with a 90 degree drill point mill, won't the outer lips of any of the drills above tend to catch before the point seats and tend to throw off the drill; 2) Which countersink might I use with common flat headed screws and bolts; 3) If I am using "screw machine" drills, do I need to spot the hole first and if so, will the bit start straight in spite of the angle differences; 4) When should I use a drill bit of 118 degrees as opposed to one of 135 degrees; 5) all other questions on this subject that I would ask if I just knew enough to ask them. Alan ------- Re: Drill bit & countersink angle questions Posted by: "russellcupan" russellcupanx~xxyahoo.com Date: Tue Oct 11, 2011 7:21 pm ((PDT)) Alan, If I understand what you are asking about, spotting hole locations before actual drilling, you may want to look at an assortment of center drills to start holes. Center drills are usually double ended and are short to pretty much eliminate deflection. They have a 30 degree per side angle on the second "step" to match the angle on most dead and live centers used on lathes. The sizes overlap to some degree, so they can be used to "spot" holes for quite a range of drill sizes. Do a search on center drills on the web, and when you see what they are about, it should all be fairly clear. You can also find charts that show all dimensions and angles used by the different sizes of center drills. Depending on what the hole is drilled for, you use the center drill only deep enough to give a good result for the finish drill to locate in. If you are going to add threads to the hole with a tap, you can use the center drill deep enough to leave a lead-in at the edge of the hole that would be just slightly greater in diameter than the tap diameter. That would reduce the chances of the top thread pulling up. As far as the various angles on the points of drills, I think that is for use on different materials. That is only my best guess as to why drills have the tip angles they do. I hope this helps. Russ ------- Re: Drill bit & countersink angle questions Posted by: "Kevin Martin" kpmartinx~xxthinkage.ca Date: Tue Oct 11, 2011 9:54 pm ((PDT)) 1) Yes. You really want the spot hole to have an angle equal or larger than the final drill, and with the center flat (left by the spotting drill's chisel point) smaller than the chisel point of the final drill. That way, the final drill contacts first at the intersection of the cutting lip and the chisel point, where there is little tendancy to dig or snag. If the final drill's first contact is cutting lip against the rim of the spot hole, or to a lesser extent outer cutting lip corner against a steep-cone spot hole, it will tend to grab and pull itself off-center. You probably don't really want the final drill to be "split point" either; such drills will find their center somewhere in the flat bottom of the spot hole, not necessarily at the center of the spot hole. The fact that the Enco flier doesn't mention spotting drill doesn't mean they don't have them. Their web site lists them and they are much shorter than even screw machine drills. 2) That depends; some flat head hardware is 82 degrees, some 90 (especially if you also consider flat-head wood screws). 3) The positional error you get drilling an unspotted hole will tend to be proportional to something like the square of the free length of the drill, so a drill with half the free length (chuck jaws to tip) will tend to have a quarter of the positional error (as a ballpark). This is assuming the stiffness of the drill is what limits walking off-center. 4) The different tip angles are for different materials; if I recall correctly the narrower angles bite more and tend to pull themselves into the work more, and so can be used with more crumbly materials like bronze and cast iron, while wider angles are used with gummier or stringier materials to prevent the bit from feeding itself too fast. Kevin Martin the Papertrail Handmade Paper & Book Arts New Dundee, Ontario 518-884-7123 www.papertrail.ca ------- Two more newbie questons [atlas_craftsman] Posted by: "Gary" topsaddlex~xxatt.net Date: Mon Oct 17, 2011 11:24 am ((PDT)) How do you do a 1/4 inch insde radius by hand? Is there a way to regrind a drill bit to 90 degrees so it makes a flat bottom hole? thanks in advance ------- Re: Two more newbie questons Posted by: "Dan Buchanan" db45acpx~xxyahoo.com Date: Mon Oct 17, 2011 11:49 am ((PDT)) Use an endmill. ------- Re: Two more newbie questons Posted by: "Russ Kepler" russx~xxkepler-eng.com Date: Mon Oct 17, 2011 12:00 pm ((PDT)) On Monday 17 October 2011 "Gary" wrote: > How do you do a 1/4 inch insde radius by hand? "Inside" like the bottom of a hole or "inside" like the shoulder of a bolt? On the latter the easiest "hand" way is to nibble it with .010 or .020 cuts, using the compound for the width and the cross slide for the depth. There are programs that will calculate the depths of the cut from the radius and cut widths, so you just walk a list of cuts playing "human servo". > Is there a way to regrind a drill bit to 90 degrees so it makes a flat > bottom hole? Sure, I do it all the time. Generally easier to use a counterbore if you've got one close. Dan suggested using an endmill, and it'll work as long as it's not a problem that the bottom of the hole isn't really flat - most endmills have some clearance built into the bottom, somewhere between 2 and 5 degrees. The clearance is so that the only cutting is on the periphery of the endmill. If you've ever used an endmill to cut a new hole in flat stock you'll remember the funny looking disc that came out the other side -- that's from the [concave] grind on the face of the endmill. ------- Re: Two more newbie questons Posted by: "Gary Richmond" topsaddlex~xxatt.net Date: Mon Oct 17, 2011 12:28 pm ((PDT)) Sorry, I meant like the shoulder of a bolt. My hub print calls for a 6 inch flange 1 inch thick, then it narrows down to 3.700 and there is a 1/4 inch radius. I will try what you suggested. Thanks for the heads up on the drill bit grinding. I have six .388 holes that have a .840 counter bore 1/2 inch deep that nuts and washers rest against. I will drill the counterbores first then recut the drill to flatten out the bottom. Does that make sense? Gary ------- Re: Two more newbie questons Posted by: "Russ Kepler" russx~xxkepler-eng.com Date: Mon Oct 17, 2011 12:48 pm ((PDT)) On Monday 17 October 2011 Gary Richmond wrote: > Sorry, I meant like the shoulder of a bolt. My hub print calls for a 6 > inch flange 1 inch thick, then it narrows down to 3.700 and there is a > 1/4 inch radius. I will try what you suggested. I forgot to mention that you'll want to file the ridges into a smooth curve. A rattail file will get the radius closer. That process will give you an OK looking radius, but if you want one that looks better you're still in form tool territory (even with the Atlas) with aluminum or leaded steel. You might do OK at very slow speeds with harder stuff. > Thanks for the heads up on the drill bit grinding. I have six .388 holes > that have a .840 counter bore 1/2 inch deep that nuts and washers rest > against. I will drill the counterbores first then recut the drill to > flatten out the bottom. Does that make sense? Sounds like a c'bore for a 1/4-something SHCS? If that's the case I'd just get the counterbore and use it; alternatively get a spare 3/8 or 25/64 drill and use it after regrinding. The piloted counterbore will cut with less chatter as the center is supported, a drill will cut but it'll tend to sing a bit if it's cutting over a lot of the face in a slightly loose hole. I have a Lisle drill grinder I use for putting a 180 degree on a drill point, it's a pain to do if you need it to cut near the center but easy for a c'bore grind. ------- Re: Two more newbie questons Posted by: "Jon Elson" elsonx~xxpico-systems.com Date: Mon Oct 17, 2011 6:51 pm ((PDT)) Gary wrote: > How do you do a 1/4 inch insde radius by hand? > Is there a way to regrind a drill bit to 90 degrees so it makes > a flat bottom hole? > Sure, it is called an "end mill". You can buy them with the tricky grinding already done. Jon ------- Re: Two more newbie questons Posted by: "jerdalx~xxsbcglobal.net" Date: Mon Oct 17, 2011 9:30 pm ((PDT)) Machinists often flat the end of a drill for that. The advantage over an "end mill" is that the drill is the same size as the hole, and will be guided by it, like a counterbore. It might eventually wear at the side of the hole, but is generally too dull on the flutes to do any harm. The end mill will happily CUT the hole if you exert side pressure. I don't see the big advantage claimed for the EM, particularly since it does NOT make the bottom flat. JT ------- Re: Two more newbie questons Posted by: "Gary Richmond" topsaddlex~xxatt.net Date: Tue Oct 18, 2011 2:23 am ((PDT)) Again, Thanks for all the imput, I drilled the holes about 7/16 inch deep then ground the drill to a flat and finished the holes at 1/2 inch. Worked slick although I sure hated to grind a new drill like that. ------- Re: Two more newbie questons Posted by: "Rick" rgsparberx~xxaol.com Date: Tue Oct 18, 2011 5:49 am ((PDT)) Drills are cheap. Just save those flat bottom drills and buy replacements. They work great for counterboring. Rick rick.sparber.org ------- EM as C'bore was Two more newbie questons [atlas_craftsman] Posted by: "L. Garlinghouse" lhghousex~xxsuddenlink.net Date: Wed Oct 19, 2011 8:47 am ((PDT)) A caution re using and end mill as a counterbore. If there is no hole already there, the only end mill that will work is a 2-fluted end mill. They are sharpened in the same way as you sharpen your flat bottomed drill -- splitting the web. This allows you to make a plunge cut. Some 3-fluted EMs have this also but most 3 and all 4 fluted endmills [at least all I've ever seen and I know I have not seen them all] have a hole in the center where all of the flutes would come together on the end. If you take a plunge cut of any significant depth the hole fills up and if you continue to feed hard enough you can "explode" the end mill. If you are centered on a pre-existing hole, then this is not a problem. The "proper" way to counter bore is to use an actual counter bore. C'bores look a lot like end mills except the flutes tend to be larger and thinner and they will have a pilot coming out of the hole at the dead center of the usually 4 flutes. The pilot is removable and if wanted, you can custom make a pilot that will fit whatever the hole size is in the workpiece. The advantage of piloted counterbores is that this can become a drillpress operation and DP operators work for less $$$ than the mill hand. The pilot assures concentricity and if the DP operator can be trusted to hold the depth, then the shop may actually make money on that operation. In my shop where time is cheap and making money is an almost phantom experience, if a hole calls for a counterbore and I am doing this on my vertical mill, I will drill the hole, then change the tool to an EM and do the c'bore before move the work piece to drill the next hole. Yes there is a lot of tool changing, but by golly everything will be concentric. If instead of a c'bore we are talking countersinking in a relatively small piece, then concentricity is not a problem because the cutting speeds are slow and the work piece can be held loosely and the c'sink will automatically center itself in the hole, so I can drill all the holes and then do the c'sinking as a separate DP [drill press] sequence. If you are a newbie going out to buy your first coutersink, MY suggestion is to buy an 82 degree one because most U.S. flat head machine screws have an 82 degree included angle at the head AND buy a "Ford" [as in M.A. not Henry Ford] or some other single flute c'sk. The multiple flutes ones tend to chatter. Obviously the world is not in total aggreement because there are a lot of multi-flute c'sks out there. Per Machinery's HB, the Brit standard included angle is 90 degrees, so if you are a U.K. newbie, get a 90 degree c'sink. Now if only someone would tell me how one sharpens a Ford c'sk in a home shop. L8r, LH Arkansas USA ------- Re: EM as C'bore was Two more newbie questons Posted by: "Jon Elson" elsonx~xxpico-systems.com Date: Wed Oct 19, 2011 9:49 am ((PDT)) No, practically all 3-, 4- and 5-flute endmills made today are center- cutting. If you manage to find an extremely old one from the 1950's or so, you might be able to find one that is not center-cutting. > Some 3-fluted EMs have this also but most 3 and all 4 fluted endmills > have a hole in the center Yes, I have certainly seen these in old shops, but I have never seen one offered for sale new since I had my own shop, and that dates to 1982 or so. But, using an end mill as a counterbore, it definitely works better if you drill the hole first. Even center-cutting end mills don't really cut all that well at the center, just like drill bits they kind of maul the very center of the hole, as the cutter is not really moving very much there. Jon ------- Re: EM as C'bore was Two more newbie questons Posted by: "Doc" n8as1x~xxaol.com docn8as Date: Wed Oct 19, 2011 1:43 pm ((PDT)) i have not seen a "new " center cutting 4 flute endmill ...bUT i have a few in my stash that were reground to center cut ..not simple to do & begs the question WHY? best wishes docn8as PS FWIW ...not difficult to MAKE a 2 lip c/bore (maybe for a special size)...just turn up some 01 to size w/ center hole for pilots, ....mill down the end to a centered flat, file/mill relief like a flat wood boring bit w/out the point of course.....put it in drill press at lowest speed (200) & heat business end till shadows disappear (non magnetic, cooked carrot color)...bring up a can of xmission fluid & quench while spinning (blow out flame)...now do the pilot ....now turn up your wife's oven to 375, put it in for an hour, shut heat off .......take out when cool .....you must run it at 1/2 normal SFM, ..& must raise up & clear chips as you c/bore (no helix flute there) years ago, i made up 1/4,5/16, 3/8 & 1/2 (smaller ones were solid c/bore) removables are easier to sharpen than solid pilot ones when you forget & run them too fast .....think abt how i know that .... ------- Re: EM as C'bore was Two more newbie questons Posted by: "Dean" deanwx~xxbmi.net Date: Wed Oct 19, 2011 3:24 pm ((PDT)) Doc wrote: > i have not seen a "new " center cutting 4 flute endmill ... Man, they are common as dirt, Doc. I have scores of end mills in my shop, many bought within the past year, and most all are center cutting 4 flute. Atrax, OSG, Putnam, even china junkers. CC 4 flute are available at all the normal machinist places. Dean ------- Re: EM as C'bore was Two more newbie questons Posted by: "Doc" n8as1x~xxaol.com docn8as Date: Wed Oct 19, 2011 9:35 pm ((PDT)) reckon i am just out of touch ...tnx for the education best wishes docn8as ------- Re: EM as C'bore was Two more newbie questons Posted by: "Starlight Tool Services Ltd" starlight_toolsx~xxtelus.net Date: Wed Oct 19, 2011 9:13 am ((PDT)) There is an attachment for the Darex XT3000 Drill Sharpener for sharpening single flute countersinks, (also available optional 3 and 6 flute cams) that does an awesome job. http://www.darex.com/index.php?page=shop.product_details&flypa ge=flypage.tpl&product_id=421&category_id=70&option=com_virtuem art&Itemid=71 Maybe it could be jury rigged to some other form of grinder, but on the Darex works slick. I had a few of these countersinks that I had sent to the company that does most of my sharpening and they returned them as not worth sharpening. Once I invested in the XT3000, no more hassles. I have a number of european craftsman in the area that brought tools with them when they came to Canada, and even managed to get the metric collets so I could sharpen their C/Ss Alternatively, MA Ford offers a Unicam Resharpening Fixture, shown in KBC Tools Catalogue, www.kbctools.com Page 69 for use on a tool and cutter grinder, surface grinder or pedastal grinder. Walter ------- Lesson Learned.... [shopbuilttools] Posted by: "gdnicholsx~xxaol.com" Date: Mon Oct 17, 2011 9:19 am ((PDT)) Following the advice I got here, I successfully drilled my cast iron table saw wings to receive a CI router table. I did disregard the advice to not use a TiN coated bit and paid the price. I had a brand new, still-in-the- package, 1/8" DeWalt pilot point bit with TiN coating. I reasoned it would be the perfect bit to drill the 5 pilot holes -- and in fact, it zoomed right through the first hole like a hot knife through butter. The problem was that it became stuck in the hole and no amount of Vice Grips manipulation would loosen it; I even tried to pull it out with a claw hammer before reached for my drilling hammer. Thank goodness it was a quality drill bit, a good bit, and it withstood hammering through the hole. OK, no more TiN bits for cast iron.... Dale ------- two excellent products [sherline] Posted by: "variousgroups" mikex~xxuncomplicated.us Date: Sat Dec 10, 2011 7:52 am ((PST)) An optical center punch and DesignCAD 3D Max. Each relatively inexpensive, both great for productivity. Mike ------- Re: two excellent products Posted by: "Ian Newman" ian_newx~xxyahoo.com Date: Sat Dec 10, 2011 1:15 pm ((PST)) Hi Mike, I've never seen the point of optical centre punches -- when do you use such a tool? If you want accurate alignment on scribed lines, you never centre punch. It is best to align to the axis of the mill or drill using a wiggler or a "sticky pin" directly onto the intersecting scribed lines, then start the hole with a centre drill (Slocom drill), a spotting (stub) drill, or a four facet drill. If accuracy is not too important then you can use a punch, but the most accurate way to punch on intersecting scribed lines is to not use your eyes at all. Engage the punch point in one of the scribed lines and then slide it down the line to the point of intersection -- you feel the punch point click into the intersecting line. If you centre punch a pair of intersecting scribed lines one or three things will happen: 1) The punch will produce a perfectly symmetrical crater that is exactly on the point of intersection of the scribed lines, so the marked point is to the same degree of accuracy as the scribed lines. 2) The punch will not be exactly on the scribed lines and/or the crater will not be perfectly symmetrical but by an amazing chance, this exactly compensates for the very slight error in marking out and so the marked point is more accurate than the original scribed lines. 3) The punch will not be exactly on the scribed lines and/or the crater will not be perfectly symmetrical and this error will add to the existing error in marking out and so the marked point is less accurate than the original scribed lines. To be honest, option one and two are not likely and the result of centre punching is almost always a degradation in accuracy of the location of the resulting drilled hole. In short, when it comes to accurate work, centre punches are the work of the Devil and are the tools of blacksmiths. Ian P.S. I have great respect for blacksmiths - they have skills I could never even begin to master -- but they are not in the business of precision and accuracy as I understand the use of those terms. (Also they are very big and strong and I am very old and fragile....) ------- Re: two excellent products Posted by: "variousgroups" mikex~xxuncomplicated.us Date: Sat Dec 10, 2011 2:38 pm ((PST)) Ian -- In measuring (see my rotary table pics in our photos section, going back to 2005 I believe) and many times in making prototypes essentially by hand first before wasting time on a precise version. Your hands are better than mine if you can accurately find the intersection of two scribed lines by feel alone and then can also punch the intersection once you've found it. I sure can't very well! But I can get very close indeed with an optical punch. Mike ------- Fw: Re: [sherline] Re: two excellent products Posted by: "JERRY G" chieftoolmakerx~xxearthlink.net Date: Sat Dec 10, 2011 3:50 pm ((PST)) Mike, then there are Toolmaker's Buttons. Just drill and tap 6-40 at intersecting lines. Install a button. Set up your workpiece on a good * surface plate. Against a good * angle plate. Tap (gently) while eyeing a .0001" DTI. When dead nuts on location, transfer to a lathe's face plate. Align the button. Remove the button. Bore to size and there you are! Jerry G (Glickstein) (Method used by many before jig borers..... ) * good signifies accurate ------- Fw: Re: [sherline] Re: two excellent products Posted by: "variousgroups" mikex~xxuncomplicated.us Date: Sat Dec 10, 2011 4:57 pm ((PST)) Jerry -- I wish I had room for a lathe and, to be honest, more experience in working with one. So when you write "transfer to a lathe's faceplate" the fact is I've never actually done that! At Questar, I've always had the good fortune of having a machinist available to turn my prototype drawings into aluminum or Delrin or whatever material we're using. But in my apartment, everything has to fit into a closet. Threading has a learning curve, too, especially the fine threading used in optical assembly, and I'm not sure I'd ever get good enough at it with a Sherline to be satisfied with the results. Questar has such a very good machinist, who can do wonders with a really old lathe, that I figure I'm ahead of the game by relying on him. Mike ------- NOTE TO FILE: The following tip relates to chain drilling along the path of an intended slot in metal, before cleaning out the slot with a milling cutter. Saves time and cutter wear. But the same jig idea would be useful when chain drilling a mortice in wood, preparatory to cleaning it up with a chisel. Good ideas can be adapted to other purposes. ------- OT RE: [Metal_Shapers] Re: new article: designing and milling slots Posted by: "RG Sparber" rgsparberx~xxaol.com Date: Sun Jan 15, 2012 8:18 am ((PST)) On January 12, 2012 Alan wrote: > Rick, can't remember where but once read a suggestion that it pays to make up prepared drilling jigs for chain drilling. I.e a thickish plate with the correctly spaced holes for a given drill size. It wouldn't have helped much in the example you used but often when chain drilling you don't need a precision slot, just a close series of holes to sever the metal spanning two saw cuts. A jig saves a lot of marking out and clamped down eases all worries about the drill holes not lining up or the drill wandering. A couple of jigs would probably take care of most chain drilling requirements. < Alan, That is a very cool idea for speeding up chain drilling. It would be most beneficial when using a drill press or hand drill. Not so good on a mill where you have to crank to a position anyway. Thanks, Rick ------- NOTE TO FILE: This next is from a conversation in the Oldtools Group. (Not on Yahoo; see link on my home page here -- a fine bunch of Galoots.) They were trying to advise how to drill holes through the fairly hard steel as in old handsaw blades. Yes they considered all the usual drill bits with or without fancy coatings (which sometimes look better than they actually perform, depending on drill bit quality and sharpness and many other factors we are familiar with in our metal working hobby). But then along came a tip I had never seen before. Glue, anyone? ------- Date: Wed, 1 Feb 2012 20:39:35 -0600 From: "genfurnx~xxexop.net" Subject: Re: [OldTools] Punching/drilling hikes in a saw plate. OK, Here I must jump in. As a wee lad, More moons ago than I care to remember or admit, I was taught the way to drill through a piece of automobile spring with a standard drill bit. You used a sharp drill, very slow speed (60 rpm or so) and moderate pressure. But the key was mucilage glue. (You do remember mucilage glue, don't you?) Put a drop of the glue where you want to drill the hole and apply pressure. Be sure to add a drop occasionally to keep it damp and you will get a proper hole through whatever you are drilling. I'm sure a saw plate wouldn't be nearly as hard as a car spring. Sounds like an absolutely crazy idea, but it does work. We used an old back-geared Buffalo drill press on the slowest speed we could get, but it should work with any variable speed drill that can go that slow. Hope this helps. Bruce Z. Kearney, MO Who has some of the good drill bits, and would still use this process to drill spring steel. ------- Date: Wed, 01 Feb 2012 20:58:24 -0800 From: "Adam R. Maxwell" Subject: Re: [OldTools] Punching/drilling hikes in a saw plate. On Feb 1, 2012, at 10:59 , Cliff Rohrabacher, Esq. wrote: > it will make a mess. Masonry biuts don't have a cutting edge ground on them they "cut" by pressure. It's not really cutting it's brute force that knocks the fines in the masonry apart. < Maybe you can clarify what you mean by "make a mess." I guess it really depends on the quality of hole that you need. I did a little demo (using electrons to turn the bit; relevancy to old tools is in fixing or making saws). Feel free to point out flaws. The material: 1095 blue tempered spring steel, Rockwell C53-C59, 0.022" thick. http://www.mcmaster.com/#catalog/118/3661/=g2g36l The bits: 1) a 1/4" HSS Borg-quality bit, made in China, titanium coated; came in a set of 1/16" to 3/8" bits. 118 degrees, unsharpened. 2) Master Mechanic 1/4" carbide tipped masonry bit, 135 degrees, also unsharpened; I think this was $2 at the local hardware store. http://gallery.me.com/amaxwell#100095/IMG_3213&bgcolor=black The results: http://gallery.me.com/amaxwell#100095/IMG_3216&bgcolor=black The hole on the far right is with the masonry bit, in basically new condition. Some elongation, but I wasn't real careful; this took about 10 seconds at ~1700 RPM. I touched it up on the Drill Doctor (a gift from my dad a few years ago), and drilled the left hole in about the same amount of time. This hole is slightly cleaner. The HSS bit blunted after a minute or so, so I sharpened it to a 135 degree included angle and split the tip, then tried again. After a couple of minutes, I had the dent on the far left. 300 RPM, medium down pressure (these crappy bits don't stand up well to brute force). I used oil with this bit, but not with the masonry drill. I don't doubt the guys that do this with cobalt or center drills, but I don't have any to play with. Anyway, the point is that you can do this with a cheap bit, and you can drill quite a few holes without ruining it or needing to resharpen. I think I had better quality holes in my saw by starting with a smaller bit and working up, but I went with the 1/4" since it was newer. Adam, having a boring evening at home in Port Angeles ------- Date: Thu, 2 Feb 2012 18:00:13 +1000 From: "John Manners" Subject: Re: [OldTools] Drilling a Saw Plate (No Borg references) Matthew Cottrell writes: "However, if you want to drill harder stuff, a larger (included) angle, like 135 degrees, works better. Sounds almost counter-intuitive, but it's true. Also, using what the trade calls a "spit point" makes a big difference." And later: "There are times when just forcing a drill through tough material (and possibly damaging the drill, and making an ugly hole in the process) may not be the right answer. I was just trying to point out that there are alternatives. "I am NOT suggesting "buy buy buy" as an immediate solution, nor do I believe in "Throwing money at every problem. Definitely back to lurking at this point." I daresay you have noticed, Matthew, that being merely informative and, hopefully, helpful around these parts is sheer provocation to some of the resident pundits to ascribe irredeemable character flaws to the man who dares to proffer such information or help. Stuff from the fitting and turning trade, including, since they have been mentioned, split-point bits in any number of sizes with the choice of cylindrical, Morse taper or tapered square-section shanks, is on offer in pretty prolific quantities at most of the fleamarkets I attend. It is only ever a matter of knowing what one wants and buying it at a tenth of its retail price. Pieces acquired usually require nothing more than a touch-up with a slipstone, if that. These circumstances have always struck me as being ideal for the average woodworker wishing to acquire the right tool for the occasional metal-working job. For me, it sure beats hell out of grinding a twist drill at a hopeful 62.5 degrees and then grinding it back at 59 degrees. Twist drills, in any event, are a woodbutcher's thoughtful grab from the metalworker's bag. Please be assured that I, for one, was pleased to receive the information conveyed in your contribution and had made a mental note to consult the McMaster-Carr site relative to the application guides which you mentioned. Regards from Brisbane, John Manners ------- Date: Thu, 02 Feb 2012 09:31:10 -0800 From: "Cliff Rohrabacher, Esq." Subject: Re: [OldTools] Punching/drilling hikes in a saw plate. The SFM should be very low for a HSS bit in steel; lower still if the steel has any hardness to it. Here is an absolutely lovely Power Point Presentation from Eastern Kentucky University people.eku.edu/sgros/content/SergioSgroP&T/Lectures/INT383.Ssgro.Met alCuttingProcess/INT201.Ssgro.MetalCuttingProcesses.ppt Here's a couple of charts on speeds & feeds: http://www.winsloweng.com/articles/drillChart_content.htm http://its.fvtc.edu/machshop1/drillpress/cutspeeds.htm They are just lifted from Machinery's Handbook. - no reason to reinvent the wheel. Charts like this force you to do a little math to fit the SFM to the diameter of the drill. But they are universal applying to both cutting tools that spin like drills and end mills and work that spins like lathe stock as well as linear stroking tools like shaper mills. Those charts do not contemplate carbide. They certainly do not contemplate a masonry bit in steel. The masonry but cannot do what a conventional bit does because it is not ground to have a sharp edge. I was impressed by the images of the masonry bit Adam used to drill the saw blade and would have enjoyed watching the development of the hole. I'd guess that the process was more like a slow and very hot extrusion of the metal deforming it locally until there was a hole and then leaving a hell of a burr to file or grind away. Certainly good enough for government work. As an aside: When drilling any thin steel like a saw blade it is always wise to trap the blade somehow so that when the drill breaks through, that it cannot grab and start the blade spinning as the cutter grabs on the last bit of metal instead of cutting it. ------- Date: Thu, 2 Feb 2012 10:26:54 -0500 From: Matthew Groves Subject: Re: [OldTools] Punching/drilling hikes in a saw plate. On Feb 2, 2012, at 12:29 AM, Adam R. Maxwell wrote: > The closest I could get was 1100 RPM by gearing down the water wheel, but it's still not working, even after I resharpened the bit. I now have a slightly larger hollow on the top of the plate and a pronounced dimple on the opposite side. I'll concede that the bit may not be sharpened correctly and it's certainly not high-quality, but I don't have anything else to try at the moment. thanks, Adam < What you're trying to ensure with the slow speed/high pressure is that the bit actually bites. If the bit don't bite, then all you're going to do with this skidding bit is work harden the material, which then makes your job that much harder. The cycle continues. You may end up needing to spot anneal the area with a torch or the backwards drill method...both are methods of applying very localized heat. What was backing up the plate such that it allowed a dimple? Was it wood? Matthew Groves Springfield, MO ------- new article: An End Drilling Guide [atlas_craftsman] Posted by: "Rick Sparber" rgsparberx~xxaol.com Date: Sun Apr 8, 2012 5:23 pm ((PDT)) This article presents a drill guide that lets you use a hand held drill to accurately drill holes in the ends of long rectangular bar stock. The article was written for those new to our hobby but others may find value in it too. If you are interested, please see: http://rick.sparber.org/edg.pdf Your comments and questions are welcome. All of us are smarter than any one of us. Rick rick.sparber.org ------- Re: new article: An End Drilling Guide Posted by: "Glenn N" sleykinx~xxcharter.net Date: Mon Apr 9, 2012 8:55 am ((PDT)) Reminds me of some of the doweling jigs I have for woodworking. Great write-up :) Thanks Rick! ------- new article: Drilling A Hole in a Slot with a Step Drill [atlas_craftsman] Posted by: "Rick Sparber" rgsparberx~xxaol.com Date: Thu Jan 10, 2013 10:57 am ((PST)) This brief article shows how to safely drill a hole through a slot by using a step drill rather than a twist drill. If you are interested, please see http://rick.sparber.org/jcsd.pdf Your comments and questions are welcome. All of us are smarter than any one of us. For the full index of my articles, see rick.sparber.org. Rick ------- Re: new article: Drilling A Hole in a Slot with a Step Drill Posted by: "printeronretainer" printeronretainerx~xxyahoo.com Date: Thu Jan 10, 2013 7:03 pm ((PST)) Thanks for posting this. This is how we newbies learn. I've run into this problem and mangled drills and metal. I'll pick up a fresh set of step- drills and use them next time I run into this problem. Rob ------- Re: new article: Drilling A Hole in a Slot with a Step Drill Posted by: "Rick Sparber" rgsparberx~xxaol.com Date: Thu Jan 10, 2013 7:11 pm ((PST)) Rob, Newbie? I've been at this hobby for over 20 years and learned this trick a few weeks ago! Rick ------- Re: new article: Drilling A Hole in a Slot with a Step Drill Posted by: "Doc" n8as1x~xxaol.com docn8as Date: Thu Jan 10, 2013 8:42 pm ((PST)) good idea Rick. wonder if grinding a flat on the rake, like recommended for brass for brass, or even maybe neg rake wud eliminate the grabbing problem ...???...i have had drills grab in sheet metal, never mind a slot ... been tempted to regrind some flat wood bits, since the olde tyme flat metal drill bits wud not grab as they exited a hole...oh well, less hassle to just get some step drills. tnx for the pics doc ------- Re: new article: Drilling A Hole in a Slot with a Step Drill Posted by: "Rick Sparber" rgsparberx~xxaol.com Date: Fri Jan 11, 2013 6:14 am ((PST)) Doc, When drilling with a hand held drill, the problem is that the cutting edge drops into the slot. It isn't that the cutting process hogs. If using a drill press and can feed in slowly, I suspect you could get away with it. One suggestion I just heard was to start with a countersink or center drill. Great idea! Rick ------- Re: new article: Drilling A Hole in a Slot with a Step Drill Posted by: "Ken Harrington" dreamcraftersx~xxmsn.com Date: Fri Jan 11, 2013 10:33 pm ((PST)) Thanks for the article Rick; step drills are very versatile some even make a nice chamfer between the steps if the material is thick enough. An alternate method I use when doing field work and don't have a step drill is to make a makeshift drill guide and clamp it over the offending slot, sheet metal, off center hole or even in cases where a larger hole is needed around a smaller one. I also do a lot of carpentry and use this trick often. It works well with bolth spade bits and hole saws using a block of wood for a drill guide. I really like the other articles on your web site to, I'm currently making up a few of the safety switches you showed, thanks Rick. Ken ------- Re: new article: Drilling A Hole in a Slot with a Step Drill Posted by: "Rick Sparber" rgsparberx~xxaol.com Date: Sat Jan 12, 2013 6:13 am ((PST)) Ken: The trick with drill guides is to be sure they are solidly clamped down. On wood it may not be as critical, but with metal, there can be a lot of force. Glad you found something useful on my web site. That safety switch idea was a gift from a friend. Sure is a clean design. Rick ------- Re: Drill press table counterweight solution [atllas_craftsman] Posted by: "Steve" skadsmx~xxgmail.com Date: Wed Jun 19, 2013 7:10 am ((PDT)) On 6/17/13 8:12 PM, "Doc" wrote: > if you are more concerned w/ function rather than 'beauty " , > i hung a pully at the top of my 1960's 15 in crftsmn drill press . > & ran a rope from the table thru the pully & back down to a pile of > barbell wts . table now moves either direction w/ just a light push & is > quicker & easier than cranking away ...just hang wts or scrap till table > is balanced all it took was to drill/tap a hole to attach th e pulley to > the head & another for the eyebolt on table That's what my dad has used for the past 20--30 years. Advantage that has over springs or air cylinders is that the force is constant across the entire range of motion (at least, until the weight lands on your foot). Dad used window sash weights. They are narrow and tall, so they won't bang into the column. Another issue is that it's hard to move the table when you pick it up at the front because you are tilting the table and it jams on the column. With the weight in the back, it balances that. Steve ------- Twist Drill Sharpener [SherlineCNC] Posted by: "Thomas D. Dean" tomdeanx~xxspeakeasy.org Date: Sun Aug 25, 2013 5:30 pm ((PDT)) Sorry, if this is too far off topic. I have some drill bits that need sharpening. I squared my wheel and ruined the first bit I tried to sharpen! I have been looking at the Drill Doctor. That seems like a simple device that may overcome my mechanical ineptitude. Does the Drill Doctor work? Is there something reasonable that is better? Tom Dean ------- Re: Twist Drill Sharpener Posted by: "jowhowho" jowhowhox~xxyahoo.com Date: Sun Aug 25, 2013 6:32 pm ((PDT)) The trick I found is not lending out my good drill bits. They last FOREVER if I'm the only one using them. When they do finally get dull, I put them in the loaner bin and buy new ones. I think the Drill Doctor is great for woodworkers. Justin ------- Re: Twist Drill Sharpener Posted by: testflyx~xxatlantic.net Date: Sun Aug 25, 2013 6:53 pm ((PDT)) My 2 cents here is if you have a grinding wheel. Why not give sharpening a dull bit by hand a try. The trick is to keep the steel from getting hot. I worked construction 20+ years ago and we drilled 1/4" steel plate on site to hang trusses to. We used 1/2" twist bits until there was almost no twist left. In fact, I would take a new bit and grind a edge on it before it was ever put in a drill. Not tooting a horn here, just saying give it a try. Once you get the hang of it, you won't have any dull bits around. BTW. I was sharpening bits using a metal chop saw and it worked just fine. It got to when one of my crew was walking toward me with a cup of water I knew he had a dull bet in his other hand. LOL ------- Re: Twist Drill Sharpener Posted by: "Thomas D. Dean" tomdeanx~xxspeakeasy.org Date: Sun Aug 25, 2013 7:16 pm ((PDT)) I have a grinding wheel and a tool to square/flatten it. I tried sharpening by hand and have now ruined two bits! I have tried this several times over the years. I usually end up buying new bits when they get dull. Drill Doctor, here I come. Tom Dean ------- Re: Twist Drill Sharpener Posted by: "bruce_e_layne" yahoogroupsx~xxthinkingdevices.com Date: Sun Aug 25, 2013 7:22 pm ((PDT)) I have a Drill Doctor and I like it. It works well, particularly for larger bits. There is a bit of a learning curve, but not so much as there is with learning to sharpen split point bits on a grinding wheel (let alone on the spinning blade of a chop saw). I'm not sure if it'll be good at sharpening the tiny bits that seem more common on Sherline tools. Be sure to check that before ordering. A tool & die maker friend of mine insists that any decent machinist should be able to sharpen a drill bit by hand on a grinding wheel, but many tool rooms and machine shops buy bits in large quantities, and they're $1 to $2 apiece. Even assuming that machinists can sharpen bits, there is no economic justification for doing so. For a small home shop that might need to buy a grinding wheel, there is even less economic incentive. I bought my Drill Doctor because I had a few fairly expensive cobalt bits that I plan to use for production, and there is a good business case for sharpening them instead of replacing them with a new bit. Some people will be best served by replacing small bits and sharpening larger, more expensive bits... either with a Drill Doctor or on a grinding wheel. Regardless, I think we can all agree that a dull drill bit is as fun as a poke in the eye with a dry stick. ------- Re: Twist Drill Sharpener Posted by: "Caparo" caparox~xxsaltmine.org.uk Date: Tue Aug 27, 2013 2:36 am ((PDT)) Tom, well you now have two bits to practice with, the drill Doctor is ok, but there is nothing like the self satisfied glow of eventually getting it right. Old addage "practice makes perfect" comes to mind. I was lucky I had an uncle with a shop's worth of old "loaner" drills and after a number of months of saturday morning cleanups, I finally managed it on a 1/2" drill (still got it 50 years on). TTFN Caparo. ------- Re: Twist Drill Sharpener Posted by: "Douglas Vogt" dbvogtx~xxyahoo.com Date: Tue Aug 27, 2013 2:42 am ((PDT)) Bought a Drill Doctor 750X a couple of weeks ago and would recommend it to anyone needing a fast way to sharpen a lot of bits. I haven't mastered split points yet and the finish on sharpened bits isn't as good as on new ones, of course. There are fine facets on the point but these can be minimized by twisting the chuck smoothly and quickly. Maybe a sharpening wheel finer than the supplied 180 grit would give a better finish. ------- Re: Twist Drill Sharpener Posted by: "Martin Dobbins" trainnutzx~xxyahoo.com Date: Tue Aug 27, 2013 6:48 am ((PDT)) There is knack (which I don't have!) to sharpening drill bits freehand, is this any help? http://www.youtube.com/watch?v=y0SQkzScQk0 Martin ------- drillbits , dirt cheap + tips [atlas_craftsman] Posted by: "Doc" n8as1x~xxaol.com docn8as Date: Sun Sep 29, 2013 1:23 pm ((PDT)) FWIW ...harbor frt has coupons for 29 bit set w/ index box, coated, for 9.99 .....originally abt $30 ...PROBLEM is more than 1/2 are unusable due to negative relief/ unequal lips .....( unbelievabley bad grinds ) .... since i hand sharpen, abt 20 min later they are usable .....compared to $ 50 + /set, i am quite happy w/ circa $80 /hr for sharpening .... pleased snuf to get 3 more sets, even thou i have 2 others at different machines.......have had no noticeable problems on 1018 & drill rod.... BUT since i hand grind, a dull bit is usable in less than 10seconds.... & in home shop, i don't have to get 100 holes / grind. fwiw #2, ....when hand sharpening OR if you want a hole closer to nominal on any bit, predrill a size under ...then the point doesn't guide the final bit & any unequal lips are mitigated to the point of not a problem, almost like reaming ......holes will be nominal to a couple thou over, depending. fwiw #3 ....slight rounding of the lips where they join the shank of the drill & you have a pretty fair reamer cutting on size, all else true. FWIW #4 the closer to abt 5 thou undersize of final hole size, the truer the reamer size will be even thou specs say 15 thou for MACHINE reamers ...for the penultimate in accuracy, a few metric bits are in order for staying around 5 thou under on commonly used holes. FWIW #5.,,,,in an emergency, a milling cutter makes a good counter bore, OR A drill bit GROUND FLAT ON END W/ LIP RELIEF ..center up on the hole first w/ a drill bit, then change to the endmil or flat drill. best wishes doc ------- Re: drillbits, dirt cheap + tips Posted by: "Scott Henion" shenionx~xxshdesigns.org Date: Sun Sep 29, 2013 2:24 pm ((PDT)) On 9/29/2013 4:23 PM, Doc wrote: > FWIW ...harbor frt has coupons for 29 bit set w/ index box, coated, > for 9.99 .....originally abt $30 ...PROBLEM is more than 1/2 are > unusable due to negative relief/ unequal lips .....( unbelievabley bad > grinds ) I picked up a set of 115 bits that I believe HF sells. Titanium coated, 0-60, 1/16-1/2, and A-Z. Several wrong size, many sharpened backwards. Grabbed the 1/8" and drilled a PT 2x4 and the drill promptly untwisted itself. Some are more than soft, others are real brittle. I'm done wasting time on cheap bits. I'll keep the cheap ones for odd sizes but pick up individual name brand ones for ones I have to sharpen often. I did get a set of cobalt bits, 1/16 to 1/4 and they are indispensable (great for drilling out hard bolts). I keep an eye on ebay for good sets at a bargain. You can get a good, used US HSS set for the same price as the useless import junk if you are patient. Just wait for NOS or closed shop gear. I picked up an assortment of Vermont American metric drill bits, about a dozen, still shrink-wrapped on cards for $20 or so. Just had a buddy give me a machinist's toolbox of bits 1/32 to 1/2 in 64ths, 0-60 and A-Z and some #60-80 sizes. A few small metric sizes. At least half a dozen of each size. All HSS an US made (back in the '80's). Wanted $100 and I near took his arm off ;) Heck, the 6-drawer cabinet was worth more than that. So now I have been tossing out many cheap bits. Scott G. Henion, Stone Mountain, GA Craftsman 12x36 lathe: http://shdesigns.org/Craftsman12x36 Welding pages and homemade welder: http://shdesigns.org/Welding ------- Re: drillbits, dirt cheap + tips Posted by: "Guenther Paul" paulguenterx~xxatt.net Date: Sun Sep 29, 2013 2:36 pm ((PDT)) Doc. Have you ever tried them? They probably won't cut hot butter. GP ------- Re: drillbits, dirt cheap + tips Posted by: "Doc" n8as1x~xxaol.com docn8as Date: Sun Sep 29, 2013 8:39 pm ((PDT)) yes i have tried them ..also sparked them & they are HS ....but only tried on mild steel or 0-1 ....i did not have any argument with them other than the pathetic grinds ....bUT like i said, takes less than 10 seconds to sharpen one off hand...& if one is unlucky enuf to get one that is a tad soft, you still can't even buy that many bits for wood, never mind the index box fot that price .....some h/frt tools are adequate, some are garbage ... you need to be careful. FWIW ....i stil have a china 14 in supposed bastard file that was NEVER HARDENED...& it IS high carbon steel ...did not come from harbor frt ... some bad stuff slips thru .....30 years ago when i framed my house i remember one #1 marked board that still had the bark on it. best wishes doc ------- Re: drillbits , dirt cheap + tips Posted by: jerdalx~xxsbcglobal.net jtiers Date: Mon Sep 30, 2013 5:30 am ((PDT)) There just is no reason whatever to buy those cheap drill sets. HS steel? Maybe. There are so many types of HSS that it's possible that they fall within one of the tolerances. A spark test won't tell you much, even if you are highly experienced. You'd have to do an analysis with one of the "junkyard guns" that give a result in percentages of ingredients. But it really doesn't matter what they are made of, HSS or pressed dog crap. The bottom line is that they do not work. Out of the usual large set, you are as likely to find wrongly sized ones, soft ones, brittle ones, or bad grinds. The one thing you don't find much is correct ones, other than a few of the largest sizes, where a defect is easily seen by the naked eye. I have had them shatter, I've had them untwist and re-twist backwards, I've had them simply not cut, mushrooming over at the end. So far I haven't noticed a reverse grind, but I'd not doubt it. Don't waste your money. The cheapest set of standard hardware store non-coated drills made here or in Mexico is far better. Particularly avoid the "coated" drills. The coating is the "pixie dust" that sells the drill, and it means nearly nothing to the average user. For you, all it does is to make junk look like useful product. The cheapest product often costs the most overall. JT ------- Re: drillbits , dirt cheap + tips Posted by: "Paul" paul_probusx~xxyahoo.com Date: Mon Sep 30, 2013 9:09 am ((PDT)) On the contrary, I have bought quite a few sets of those $10 HF specials and aside from one set where there were some mis-ground bits, I have been pleasantly surprised by them. I would agree that they can be ground better, I spent $80 on a 29 pc. Craftsman set in the early '90's and they did drill cleaner holes, when new, compared to the HF cheapies. But I have not found any of the unhardened or grossly mis-made horrors that others say they have found (and I found in a set from a different distributor). As I said earlier, I think it was the first set I bought had some that were not ground properly in the smaller sizes, all the other sets have been very good and useable right from the crappy index they come in. I did buy a 115 pc. set (letter, number and fractional in one) from either Homier or Cummins(Toolsnow) after having good luck with the HF's and they are horribly made. I made the mistake of assuming HF and Homier/Cummins had the same supplier and thought the 115pc set would be OK, too. Paul ------- Re: drillbits , dirt cheap + tips Posted by: "Bruce Monson" bmonson61x~xxhotmail.com Date: Mon Sep 30, 2013 10:40 am ((PDT)) I also got one of those 115 piece sets. Couldn't even ream a hole in mild steel. Bruce ------- Re: drillbits , dirt cheap + tips Posted by: harryx~xxharrymcdaniel.com Date: Mon Sep 30, 2013 12:07 pm ((PDT)) I have a HF fractional/letter/number coated HSS set that I bought 10 years ago. It has been great for those infrequently used sizes. I have found several with negative relief or inaccurate sizing, but most are OK. I have drilled a fair amount of stainless with them and they do the job as long as I keep them sharp. For frequently used sizes I get better bits. ------- Re: drillbits , dirt cheap + tips Posted by: "James Smith" smith975x~xxcharter.net Date: Mon Sep 30, 2013 12:10 pm ((PDT)) I have been using HF drill bits for years, yes the first ones years ago were crap but the newer ones seem to work as well as any others I have. I normally drill with a press set on slow speed and I use a set of US made colbalt bits for drilling knife blanks. But for mild steel I normally use HF bits. I also grind my bits with a Drill Doctor bit grinder before use if they don't feel right, I have two Drill Doctors a small one and a larger one, the almost 70 year old eyes just don't see well enough to free hand anymore. Fact is I just got back from HF with a 115 piece set of their colbalt drill bits just to give them a try and see how good or bad they are, with a 20% off coupon they were $80 a compareable set US made is over $700. I'm also finding more and more things marked USA on them are just packaged here not made here. Sure I would like to only buy USA made, but the old retirement check only goes so far. JS ------- Re: drillbits , dirt cheap + tips Posted by: jerdalx~xxsbcglobal.net jtiers Date: Mon Sep 30, 2013 8:20 pm ((PDT)) Actually, you are more-or-less proving that quality is extremely variable in those "sets". The ones with the gold colored coating ar the worst..... I'd almost believe a set with no coating... they aren't trying to hide anything behind the "bling". But the gold coating (supposedly titanium nitride) is usually a marker for utter crap in cheap sets. If you buy decent drills (garage sales and tag sales are a great source) then you will get far better results. But please... suit yourself JT ------- Re: drillbits , dirt cheap + tips Posted by: "Chris and Judy Zahnle" chrisandjudyx~xxcableone.net Date: Mon Sep 30, 2013 8:33 pm ((PDT)) Good tools are not cheap, Cheap tools are not good. Chris in WA ------- Re: drillbits , dirt cheap + tips Posted by: "Rick Sparber" rgsparberx~xxaol.com rgsparber Date: Mon Sep 30, 2013 8:51 pm ((PDT)) In general I agree but there are exceptions. I paid over $150 for a name brand digital caliper which never held zero. I paid $10 for a Harbor Freight digital caliper and it is solid. It would sure be a much simpler world if you ALWAYS got what you paid for. Rick ------- Re: drillbits, dirt cheap + tips Posted by: "Doc" n8as1x~xxaol.com docn8as Date: Mon Sep 30, 2013 9:38 pm ((PDT)) blanket condemnation w/out personal emperical evidence for the particular item in question is ususally suspect & carrys the not so faint odor of unsupported predjudicial opinions.......while there is still plenty of garbage at harbor frt, their quality AND price have been steadily increasing, & yes quality cud hardly go any other way, so comparisons of different sets of bits and from different time frames is apples & oranges. i remember seeing wrench sets early on at h/frt & i thot, "no way wud a chineese mechanic use this crap"...surely they must make better stuff than this.....much later i bought a combination wrench set up to abt an inch or a little more, for an xtra set in the garage ...chrome vanadium w/ a "snap on polish"....properly sized & have withstood 18 in cheater w/ out snapping nor mushing .....leather wrench roll, but once again, everything first class xcept one thing: stupidly faced w/ plastic, which did not last a year ...i replaced it w/sewing on part of a blue jean leg. i later bought sets for two sons ...it has been maybe 10 years & i have heard no complaints. FWIW ..china is not alone in producing garbage .....i remember when anything from japan received the same pejorative comments as china stuff today, that was more than 60 yrs ago ....today, made in japan labels are desireable .....west germany stuff after WW2 was not up to the usual german standards.......and just for the record ...i remember the garbagy tools i bought in the five & ten cent stores as a kid just before WW2 & during, cause it was all the money i could come up with ...all AMERICAN made, & as cheaply fabricated as possible. best wishes doc ------- Re: drillbits , dirt cheap + tips Posted by: "Carvel Webb" carvelwx~xxabsamail.co.za Date: Mon Sep 30, 2013 10:26 pm ((PDT)) I would agree with Doc that one should be careful of generalisations. I have tools and instruments which have come from all over during the years and it has been interesting to see how quality, and more importantly quality control has evolved. FWIW the worst wrench set I have was made in the USA (about 30 years ago), my best and worst chucks both come from the UK. I have a Taiwanese chuck that is on par with my best UK chuck, my best and worst calipers both come from Japan, and my best and worst ring spanners both come from Germany. Not always possible, but try it or ask someone who has first. This and other similar forums help with that and is appreciated. I am very fond of my Atlas (10F), but its manufacturing and design compromises are obvious if I compare it to my Myford of a similar age – but I wouldn’t part with it ( literally and figuratively :>) ). Regards, Carvel ------- NOTE TO FILE: A discussion in the Metal_Shapers group at Yahoo started about problems drilling out a bolt and then wandered off into shaper repair tips. The drilling portions of that conversation will be useful to anyone on any machine. In the Metal Shaper Repair General text file, find the conversation which starts with this message: Re: Drilling Out Broken Toolpost Bolt [Metal_Shapers] Posted by: "Don & Mary Barth" dmbarthx~xxhughes.net Date: Wed Nov 20, 2013 6:49 am ((PST)) ------- Drilling holes accurately in the right place [myfordlathes] Posted by: qthurtlex~xxgmail.com busybeingrelaxed Date: Wed Jan 15, 2014 7:11 am ((PST)) Basic novice metalworking questions, not specifically lathe related:- When laying out a series of holes on aluminium or steel plate, I use a scribe, tiny steel square, etc. This leaves me with a pair of fine lines which cross at the point at which I want my hole to be drilled. I then get an automatic centre punch (which seems easier to place at the intersection than a standard punch) and punch a mark at the intersection. All good so far (I think). For a small hole, (eg up to 4 or 5 mm), I would get the drill in my drill press, and drill through in one pass. For a larger hole, I would normally drill a 3mm hole and then open it out by a few mm at a time until I got to the final size (eg 12.5mm). Question 1: Are the above strategies roughly right, any comments? Question 2: Assuming the centre-punch mark 'pulls' the drill to the right place, what is the maximum size of hole which can be accurately centred by a mark from a centre-punch? Question 3: Is there an advantage in having the drill extending from the chuck by a large distance, so it can 'wander' into the centre-punch mark more easily? I have a small drill press and for larger holes, I never bother to clamp the workpiece to the press platform, because I know that I will have to unclamp the platform and then lower it (and hence lose alignment) to accommodate the increased length of the larger diameter drill bits. (I probably could clamp everything up and work with the quill at a large extension for the small drills if I thought a bit more at the start!) I hold the work in a 4" cast iron vice, roughly align it and let it 'float' as I drill the hole. Question 4: Any thoughts on the method described above? Question 5: Are there any strategies for re-aligning drill bits centrally in the drill press, once alignment has been lost due to moving the workpiece. Rhetorical Question 6: Why are there no metalworking evening courses any more? Best wishes Q ------- Re: Drilling holes accurately in the right place Posted by: garthnx~xxpbt.co.za garthn444 Date: Wed Jan 15, 2014 7:24 am ((PST)) It might be frowned on, but I use my micrometer to mark out, with engineer's die. Much more accurate than a ruler/square, and easier and quicker (eg if I need a hole 5mm and 10mm from two sides, mark two perpendicular lines, the only time taken is to set the micrometer). There can be some error of parallax as the micrometer cannot be held totally in plane, as one jaw must overlap the side, but without calculating it I would guess it is very small. You're missing one key thing - a centre drill. Normal drill bits flex, they will not get pulled to the punch mark but will more likely stretch it. A centre drill is much stiffer and the small point allows it to be seated in the punch mark. If the bit is extended and flexing, you will get an oversize and inaccurately placed hole. I prefer using more bits than less, especially when approaching the final hole size. As I read somewhere, if your final bits are incremented very slowly, you can actually find you cannot get the final bit into the hole by hand. Interesting but true. You can use a loupe or magifying glass to get the punch mark (and resultant hole) more accurate than your eye can see. Not sure what you mean by question 5? is your drill press/chuck not accurate? Engineer's marking dye is good for laying out, without scratching lines in the metal itself. Acetone flushes it off. Reamers are used for really accurately sized holes. ------- Re: Drilling holes accurately in the right place Posted by: "Ken Strauss" ken.straussx~xxgmail.com Date: Wed Jan 15, 2014 9:24 am ((PST)) What you write sounds like typical practise except, as noted by others, using a spotting drill may be helpful. The best technique to use is determined by the necessary accuracy and the tools that you have available. If available, using a vertical mill would give better accuracy with less effort than what you described. Using only a lathe you can get even better accuracy by using toolmaker's buttons and mounting the work in your 4-jaw chuck or on your faceplate. See http://www.youtube.com/watch?v=IPV54iNBo1M and http://www.home ws.co.uk/page273.html for an explanation. ------- Re: Drilling holes accurately in the right place Posted by: "David Littlewood" davidx~xxdlittlewood.co.uk Date: Wed Jan 15, 2014 3:07 pm ((PST)) For most work - provided you are only working to 0.2 mm or so. If you want greater precision you would need to use more sophisticated methods >Question 2: Assuming the centre-punch mark 'pulls' the drill to the right >place, what is the maximum size of hole which can be accurately centred >by a mark from a centre-punch? None, IMO. You might get away with it some of the time, but in thicker plate you risk breaking the bit. As far as "what size", you have to get some knowledge of the way a twist drill works. The end part between the flutes is basically a chisel point, with a very negative rake, and it needs to plough its way into the metal by brute force. Thus a pilot hole should always be at least equal in diameter to the length of the chisel edge. >Question 3: Is there an advantage in having the drill extending from the >chuck by a large distance, so it can 'wander' into the centre-punch mark >more easily? NO!! Get the B****y thing in the right place to start with. >I have a small drill press and for larger holes, I never bother to clamp >the workpiece to the press platform This (drilling sheet material in a drill press without clamping it) is a recipe for slashed hands - if not this time, some time soon. The drill is sure to grab as it breaks through, and if the sheet is not held it will spin round rather rapidly. You can get away with it for very small holes - say up to 2 or 3 mm - if you hold them firmly, but it's best avoided altogether. >Question 5: Are there any strategies for re-aligning drill bits centrally >in the drill press, once alignment has been lost due to moving the >workpiece. Well, I suppose you mean "aligning the work under the drill axis". Yes - use an optical finder. If (as I guess is highly likely) you don't have one, you can get pretty close by putting the original drill bit in the machine, and align the work to it, then clamp down. It may help to put the original bit in the wrong way up to avoid the drill lips cutting their way in when slightly off. >Question 6: Why are there no metalworking evening courses any more? Not enough demand. Why fill the resources with a couple of old fogies when they can fill rooms with endless cookery, art and gardening classes and such stuff. My best advice to you - BUY THIS BOOK: http://www.amazon.co.uk/Drills-Taps-Dies-Workshop-Practice/dp/0852428669/ ref=sr_1_12?s=books&ie=UTF8&qid=1389802807&sr=1-12&keywords=tubal+cain It's less than £6, and it will teach you more about drilling than almost anything. David Littlewood ------- Re: Drilling holes accurately in the right place Posted by: "Ian Newman" ian_newx~xxyahoo.com Date: Thu Jan 16, 2014 6:30 am ((PST)) Hi Q, As others have pointed out, the centre punch mark is not intended to "pull the drill" - you are supposed to put the material in the correct place. Try using a "sticky pin" to centre the drill on the crossed scribed lines. The centre punch is the work of the Devil - I would advise you not to use it. Drill directly on to the scribed lines with a four facet drill or a Slocombe bit (centre drill). Consider the options when using the punch: 1) You have an accurately scribed location and when you punch the intersecting lines, the punch mark is perfectly placed and perfectly symmetrical. You will now drill the hole in the intended location. This will never happen as the real world results in case 2) below. 2) You have an accurately scribed location and when you punch the intersecting lines but the punch mark is NOT perfectly placed and not perfectly symmetrical. Now when you drill, the hole will not be where you marked it - the punch mark introduces an error. 3) The final option is that you have an error in your marking and by a miricle the error introduced by using the punch exactly compensates for the error in you original layout - just like option 1) this is not going to happen.... Finally - when drilling large holes using a series of steps, rather than drilling all the holes at one size, changing the drill and going through all the hole again, it is better to secure the work and drill all the steps for a single hole and then move to the next hole. That way you do not need to reposition the work on an existing hole. All the best, Ian ------- Re: Drilling holes accurately in the right place Posted by: "Andrew Moyes" admx~xxamoyes.fsbusiness.co.uk Date: Thu Jan 16, 2014 6:46 am ((PST)) I get very good results from an optical centre punch like this. http://www.chronos.ltd.uk/acatalog/punches_scribers.html A bit pricey but it gets a lot of use and I find it much more accurate than an automatic spring loaded centre punch. Andrew M ------- Re: Drilling holes accurately in the right place Posted by: "Kevin" tadpolex~xxbtinternet.com klokenz Date: Thu Jan 16, 2014 2:07 pm ((PST)) For most work on the drilling machine I mark out scribed lines, having coated the metal with a black felt-tip marker pen, just in the area where the lines go. I scribe with a needle held in a small pin chuck. I align the work by using a length of steel round stock which has an accurate sharp point turned on one end. This goes in the drill chuck. The work piece is clamped up in a cheap cross-vise which is clamped to the drilling machine table. It's easy to align the work by twiddling the handles until the point is on the intersection. Sometimes I'll use a low power loupe to aid alignment. One of the crummy gib adjusting screws on each slide has been replaced with a socket head screw which gets nipped up to lock everything before drilling. Nothing gets drilled without it being clamped. For larger stuff I use a piece of wood with a block on the underside which goes into the vise jaws, and G clamps of various sizes to secure the job. Or woodscrews. Start drilling with a centre drill then step drill as needed. Some people object to using a centre drill for this work and preach the benefits of spotting drills, and I have no beef there ... I might buy or make some one day. For more accurate work I often make simple drilling jigs. Strictly speaking these make for more precise rather than more accurate work. Useful for matching multiple holes in more than one workpiece. A lot can be learned from the books, as David suggested. There is also plenty out on the web about old toolmakers' methods, which are well worth reading. If I had the equipment, I would simply set the job up on the table of a suitably sized milling machine and use the DROs to locate the holes. Kevin, NW England, UK ------- Re: Drilling holes accurately in the right place Posted by: ejandptrx~xxbtinternet.com Date: Thu Jan 16, 2014 2:40 pm ((PST)) Kevin, No problem with using centre drills to start the ‘ole, in fact was taught that way. The trouble is those little points are so easy to break off, and so difficult to get out of the hole when they do. Spotting drills on the other hand! Phil ------- Re: Drilling holes accurately in the right place Posted by: "Phil" pipx~xxhvtesla.com philiptuck Date: Fri Jan 17, 2014 12:51 am ((PST)) Andrew, What is the central body made from, steel? I'm just thinking about its ability to stay in position whilst the rods are swapped. As you say pricy, but I rather like the idea - centre punches and my eyesight don't mix well. PS: It's out of stock at present if anyone is tempted. Regards Phil T ------- Re: Drilling holes accurately in the right place Posted by: "David Littlewood" davidx~xxdlittlewood.co.uk Date: Fri Jan 17, 2014 7:06 am ((PST)) Phil, I used one of these until I acquired an optical finder which fits in the machine; it is probably the best method of making a punch mark if that's what you want to do. Mine is by "Dankroy" and has an O-ring just proud of the bottom surface to resist slipping. Having said that, even if you have an accurately placed punch mark, you still have the problem of getting it aligned with the drill axis. Over the years, I have gone through various iterations, each resulting (I hope!) in greater accuracy. First was using a normal punch by eye (and I don't mean an automatic one, I find these are harder to control). Then the Dankroy optical punch; then the optical centering device in the mill (based on a microscope objective and eyepiece). The final one is a DRO fitted to the mill, using an edge finder to locate the edges of the work, and then using co-ordinate drilling. Sometimes there is no suitable edge to use, then I have to go back to the previous method. However, bear in mind that all the first 3 methods rely on accurate measurement by hand methods; the final one is streets better, I can routinely locate holes with an accuracy of about 0.02 mm or better, and a repeatability probably half that. Have you bought that book yet? David Littlewood ------- Re: Drilling holes accurately in the right place Posted by: qthurtlex~xxgmail.com busybeingrelaxed Date: Fri Jan 17, 2014 8:46 am ((PST)) Thank you so much for the contributions to my questions. People on this forum are so generous with their time and expertise. The answers (so far?!) are very helpful and give me much food for thought. I am far better informed now than before. I just need to put some suggestions into operation and see where they take me. The book has been ordered! Best wishes and thanks again. Q ------- Re: Drilling holes accurately in the right place Posted by: "Andrew Moyes" admx~xxamoyes.fsbusiness.co.uk Date: Fri Jan 17, 2014 11:14 am ((PST)) The body is light alloy, black anodised I think. The bottom has a rubber pad glued on. Enough to hold it in position if you kept light pressure on it while you swap the lens for the punch. The same product is available from several suppliers if Chronos are out of stock. A far eastern product. Mine is OK except the tip of the punch didn't last long but it didn't take long to make a replacement out of silver steel and hardened it. Not as good as the Dankroy mentioned by David but no doubt cheaper. http://www.dankroy.co.uk/ocp.htm Andrew M ------- Re: Drilling holes accurately in the right place Posted by: ianturneresqx~xxhotmail.com Date: Sat Jan 18, 2014 3:00 am ((PST)) I've used a Dankroy optical punch for many years with good results (for my needs anyway) - much more accurate than the automatic centre punch I also have - which always seems to move away from my intended placement (obviously some form of 'user' error!) I was curious as to how much they (the Dankroy) might be now but couldn't see any pricing on the website. I don't think they would be too hard to make - both the body & punch are simply turning jobs, the perspex rod would be the most difficult part I would think. Regards, IanT ------- Re: Drilling holes accurately in the right place Posted by: "Bob Hamilton" bobx~xxhamilton-bob.freeserve.co.uk Date: Sat Jan 18, 2014 3:26 am ((PST)) Chronos do a Soba setup at £32 which is currently out of stock. Axminster also do this and are showing availability. Bob ------- Re: Drilling holes accurately in the right place Posted by: "Andrew Curl" methuselahx~xxntlworld.com Date: Sat Jan 18, 2014 3:28 am ((PST)) I bought my Dankroy almost 20 years ago, and it cost me £30 then. It was bought from Chronos, when they were still operating out of a shed in St Albans. Of course in those days, I didn't have things like mortgages, and the time/money ratio was far more favourable than it is now. I never looked back, but if I had made a priest punch myself, it would have catered for many of the same needs. Optical punches are great when the marking lines are set out using marking fluid, and there are no deep scribed lines to "feel". Stuff like horological work, I'd imagine. Truth be known, there really isn't anything to them, if you have some scraps of ally, silver steel, perspex and an "O" ring for the base. My Dad fancied one, and indeed, the only tricky part was the "perspex bit". He eventually made up Westbury's radius turning tool just for the job, although I am unsure if he ever completed the punch! If you do decide to have a go, make a few "perspex bits" while your machine is set, as a classic mistake (and I've seen it many a time in industry) is to belt the "perspex bit" with a hammer before replacing it with the punch itself... Sounds silly, but its easily done; just not in my workshop, as I pay for my tools instead of the Boss! Andrew UK ------- Re: Drilling holes accurately in the right place Posted by: davetherave11x~xxgooglemail.com Date: Sun Jan 19, 2014 2:11 am ((PST)) On my apprenticeship I was taught to mark out using a vernier height gauge. Centre-punching was frowned upon, instead we would use a centre- finder / "wiggler" to align the drill chuck with the marking out. Then start the hole with a centre drill. The problem I have at home with this method is that the wiggler is much longer than a centre drill, and the short travel of my bench drill will not accommodate both in a single setting. ------- myfordlathes: Making optical punches, was drilling holes accurately Posted by: tobybishopx~xxaol.com tsb2225 Date: Sat Jan 18, 2014 3:23 am ((PST)) Hi All. I've got rubbish eyesight and really struggle to punch the intercept of a pair of scribed lines with any accuracy so I made an optical centre. There are a couple of sites that I looked at that were very helpful: http://www.gadgetbuilder.com/OpticalPunch.html http://www.nucleus.com/~harlan/punch.html As Ian commented below the trickiest bit was the perspex magnifiying section. After some calculation my one was made 50mm long with a 16.5mm radius lens co-ordinate turned on the top. This was polished until clear. The bottom face of the perspex rod is flat and sits about 0.5 mm above the scribed surface and has a tiny circle on it that was scratched on with a scriber with the perspex in the lathe. The punch is a piece of tool steel rod I had and I made the base and perspex to fit the punch. I find it works really well; even when checking the punched placement with a microscope, I can discern no offset from the scribed lines. I generally use a digital height gauge to place my lines. cheers Toby Ah, sorry. The Harlan punch site seems to have been taken down but the gadget builder one still works. ------- Re: Drilling holes accurately in the right place Posted by: "Robert Mitchell" rmm200x~xxyahoo.com Date: Sun Jan 19, 2014 6:54 am ((PST)) Try shortening the wiggler. Nothing magic about the length of the pin. Robert Mitchell ------- Re: Drilling holes accurately in the right place Posted by: "Kevin" tadpolex~xxbtinternet.com klokenz Date: Sun Jan 19, 2014 7:38 am ((PST)) As mentioned earlier I normally use a short pointed rod in the drill chuck and align by eye, sometimes with magnification. Drilling in the lathe I sometimes use the "sticky pin" that Ian mentioned ..... the pin lives in a blob of "Blu-tack" on the end of a shelf above the lathe, next to the block of wood used to loosen the chuck. There is another method of locating a centre that I recently learned of, but haven't yet tried, that sounds rather good. There is a type of edge finder which features a rod cut into two pieces which are joined by an internal tension spring, the butting faces having been lapped flat. The lower portion is normally an accurately known cylinder, but some sets include one which has a cylindrical portion ending in a cone. The idea is that you chuck the body in your drill chuck, lower the quill and move the workpiece until the point enters the centre mark, which can ideally be just a prick mark. This will have offset the two parts of the device. Now the clever part ... you move the work around (in my case by adjusting the cross-vise) and observe the junction between the two parts of the device. When it gets very close it is claimed that by running your fingers over the junction you can rather sensitively detect any slight misalignment, and so bring the work to proper placement. Haven't tried it yet. Kevin, NW England, UK ------- Re: Drilling holes accurately in the right place Posted by: "David Littlewood" davidx~xxdlittlewood.co.uk Date: Sun Jan 19, 2014 10:48 am ((PST)) davetherave11x~xxgooglemail.com writes > On my apprenticeship I was taught to mark out using a vernier height gauge. Centre-punching was frowned upon, instead we would use a centre-finder / "wiggler" to align the drill chuck with the marking out. Then start the hole with a centre drill. The problem I have at home with this method is that the wiggler is much longer than a centre drill, and the short travel of my bench drill will not accommodate both in a single setting. < This is a common problem when using a drill press, or a milling machine of the rather rudimentary far eastern type which has no method of maintaining alignment when moving the table or head. The obvious solution to this issue -- it also applies when you need to move from a short centre drill or a pilot drill to a larger drill -- is to make an extended version. Just drill a hole in a piece of mild steel rod of suitable length, and retain the centre drill either with Loctite or a grub screw. The you don't need to move the head up the column when moving to a larger drill bit. David Littlewood ------- NOTE TO FILE: Such an extension may result in a less stiff initial setup for the centre drill. The alternative after using a short centre drill is to do the final drilling (where practicable) with a short drill bit. ------- Re: myfordlathes: Making optical punches, was drilling holes a... Posted by: "Ian Newman" ian_newx~xxyahoo.com Date: Mon Jan 20, 2014 8:18 am ((PST)) Hi, You can try looking for the archived copy of the ~harlan punch on the "wayback machine" at: http://www.archive.org/ All the best, Ian ------- HELP! Problem! Poor Technique? [sherline] Posted by: "Tom & Judy Bank" trbank1x~xxverizon.net Date: Fri Feb 7, 2014 1:52 pm ((PST)) Jerry, I got a problem! It started last week. To tell the whole story, it started when I needed to hold a fixture on the mill table. I could have grabbed one of Sherline's little "L" shaped clamps from where I keep it with the Sherline accessory it came with, but I realized that the one I pulled out had the wrong length screw on it. If I changed the screw, that screw could then be misplaced, used for another purpose, or mixed in with my hoard of 10-32 screws of multiple lengths. HA! Instead of changing the screw, I decided that I would make enough extra clamps that I could just grab one from supplies on hand when needed, rather than stripping one that came with another appliance and then having to look around for yet another after not replacing that one when I was done with that job. I looked in my scrap box and quickly found a piece of square steel tubing, walls maybe 3/32" thick, that I saved 20 years ago when the place I worked was throwing out a bunch of crappy desks we had been using. The square tube had been a leg on one of those desks. Other steel that had been in my supply that long had a slight sheen of rust, but this piece had none, so I thought maybe it was stainless. Anyway, I was able to saw, mill, and file a dozen "L" clamps out of it without any problem. But when it came to drilling the holes for the screws, doing that job was a nightmare. I finally got the holes done, spotting the holes and using cutting fluid, but I had to force it; and when the drill went through, it produced a nipple on the far side that extended as far out as the diameter of the 10-32 clearance hole. My guess was that I had heated the metal enough that instead of drilling, I had "shaped" a hole the way you would form a cup in a piece of sheet steel. I figured that the steel involved was some odd SS alloy that wouldn't drill, but I was puzzled that I had no problem sawing, milling, and filing, only drilling couldn't be done properly. Then last night I again had to drill four #30 holes in steel. This time two holes had to go into a piece of CRS and the other two holes - which would be turned into slots - needed to go in near a lower corner of the mill vise jaw inserts. Previously I had successfully drilled the same piece of CRS without problems, and once again I had no problems sawing, grinding, milling or filing either metal. But when it came to drilling, I wore out the cutting edges on two brand new jobber length and screw machine length drills, and finally broke a center drill. When I finally went to bed at 2:00 A.M. I had done what was necessary, but it looked like I had been digging ditches with a spade, piles turned up around the tops of holes and a lump like a festering boil on the other side. I took a Dremel cutoff wheel and ground the "boil" down, which then, thankfully, opened the hole up enough that I was able to get yet another drill to open it to full diameter. Then I ground and hand filed the required slots. But as I say, the final result is not pretty and I am going to add a new set of vise jaw inserts on my next order to Sherline. On what was intended to be the slots in the jaw inserts, I admit, I boo- booed. I did have on hand a ?" carbide end mill. I should have put the inserts horizontally in the vise and then put the required slots in place with that tool. I will do that next time. But my question is, do I need to get a set of carbide drills (actually a couple sets - number as well as fraction) to drill in steel? I've never had a problem like that before, and I'm wondering if others have experienced anything like what I described – and can recommend procedures to avoid it happening again. As I say, I did use plenty of cutting oil. As I have been taught, a screw-up like this – as long as I don't maim myself or damage my machines – is a learning experience, so I value any assistance anyone can give me in improving my machining practice. Regards, Tom Bank ------- Re: HELP! Problem! Poor Technique? Posted by: "Charles Fox" cafox513x~xxverizon.net Date: Fri Feb 7, 2014 3:04 pm ((PST)) I hope this photo will come out at least in the message I’m sending directly to you, Tom. This represents way less than $50, including the ink to print the labels with the various sizes inside each compartment. I scored these in one visit to a fully stocked hardware store. “Highly recommended” as you’ll find you need slightly different length screws for various applications of those absolutely vital little L-clamps! ------- Re: HELP! Problem! Poor Technique? Posted by: "Tom Wade" tomx~xxwade.name Date: Fri Feb 7, 2014 3:13 pm ((PST)) My guess is to only buy special bits in the sizes that you actually need. I tend to buy cobalt bits for hard steel. I have many three or four sizes on hand. YMMV. Tom Wade Hope, Indiana ------- Re: HELP! Problem! Poor Technique? Posted by: chieftoolmakerx~xxearthlink.net Date: Fri Feb 7, 2014 9:37 pm ((PST)) Tom, gut reaction. I think, except for the CRS, you were a victim of a work hardening Stainless Steel. MxMaster-Carr sells rectangular tubing. Some even perforated! No drillng. :) Would you consider buying a ? Then, you could re-sharpen or re-point your drills. Jerry G (Glickstein) P.S. It is easy to come along after and tell a person what you think they should have done. :) ------- Re: HELP! Problem! Poor Technique? Posted by: "ED MAISEY" holmes_ca_2000x~xxyahoo.com Date: Sat Feb 8, 2014 12:45 am ((PST)) Tom, after reading Jerry G's post, have you placed a magnet on the material. I know some St/St is magnetic but it's worth determining. http://www.cartech.com/techarticles.aspx?id=1476 Edmund ------- Re: HELP! Problem! Poor Technique? Posted by: "Andy M" trumpy81x~xxoptusnet.com.au Date: Sat Feb 8, 2014 12:39 am ((PST)) GDay Tom, To me, it sounds like one of two problems, dull drill bits (new does not always mean sharp ;) or they are carbon steel drill bits which are OK for wood, aluminium and plastic but no go with steel. If you buy replacements make sure they are HSS, Cobalt or Carbide. Carbide being the best choice, a little expensive but worth it in the long run. You'll need a diamond wheel to sharpen them too ;) Regards Andy M ------- Re: HELP! Problem! Poor Technique? Posted by: "JERRY G" chieftoolmakerx~xxearthlink.net Date: Sat Feb 8, 2014 3:26 am ((PST)) Hi Edmund, ( Hi to Gisele :) Good idea. I had worked a lot with series 416 Stainless Steel, which machines like CRS, but the magnetic pull is relatively weak. Having a supply of stock on hand is good, but it is prudent to know what you are working with. In industry, color coding of materials is well known. Tom had a rough time trying to do a simple job. I have a lot of Sherline clips. I have a lot of 10-32 Allen Socket Head Screws in different lengths. They are employed where and when they are needed. A good setup is worthwhile to build and leave set up to amortize the time spent making it. Always leave a set up until you MUST break it up. Jerry G (Glickstein) ------- Re: HELP! Problem! Poor Technique? Posted by: "Ian Newman" ian_newx~xxyahoo.com Date: Sat Feb 8, 2014 4:47 am ((PST)) Hi Tom, Seconding comments from other people: As Jerry pointed out, from the lack of rust bloom it is possible you have entered the realm of work-hardened stainless steel. Edmund suggests the magnet test which works 99% as most stainless you tend to come across is the nickel alloy. 300 series SS (ie that with nickel content) is non- magnetic but the 400 series will exhibit magnetic properties. Try a spark test on the material - SS has a shorter spark stream than mild (low carbon) steel and has a characteristic straw (browny-yellow) colour next to the wheel, changing to white for most of the stream length. Comparing the MS spark with the SS, SS has fewer "forks" and lacks the "blobs on the end" that are present in the MS stream. Of course the above will not account for your second difficult drilling experience - especially as you have successfully machined the material before. As others have commented, check your new drills for sharpness, although as you have experienced the same problem with several different drills from (probably) several different sources it is unlikely that this is the problem. Check the drilling spindle for play. All the best, Ian P.S. Congratulations on being able to break a centre drill! They are, by design, very robust - I have only very rarely be able to snap the pilot tip off, it is a feat that takes great determination and of which you should be proud. It is always reassuring to get advice from people who have broken things - they are the ones who have "gone too far" and truly know the limits...... ------- Re: HELP! Problem! Poor Technique? Posted by: "Terry Looney" loon432x~xxverizon.net Date: Sat Feb 8, 2014 1:22 pm ((PST)) Tom, When I was teaching metal trades at our local vo-tech school, I had some students mounting fixtures to the welding tables for vertical and overhead samples. This involved drilling several half inch holes through a half inch steel plate. They started with a new half inch drill. Soon after starting they brought the drill bit to me to sharpen. Some time later I sharpened it a second time. The third time they approached me, I decided to investigate their technique. They were half way through the plate, so I told them to show me how they were drilling the hole. They inserted the bit into the hole and turned the drill on. I immediately told them to stop. It works better if the drill is running forward. Reminds me of an electrical engineer I worked with that did a lot of troubleshooting over the phone. The first question he always asked was "is it plugged in?" Terry Looney ------- Re: HELP! Problem! Poor Technique? Posted by: "Tom & Judy Bank" trbank1x~xxverizon.net Date: Sat Feb 8, 2014 1:23 pm ((PST)) To all, Thanks for the help. I answered Charles separately and I will get what we discussed on the way next week. I did start out thinking I would email Jerry G. directly, but then changed my mind and sent to both groups, but failed to remove the "Jerry" in the opening. Tom Wade and Jerry Feldman recommended cobalt drills. As Jerry F. suggests, I think I will replace the drills that go dank with cobalt. And Andy, thanks for your advise as well. In future I will try to focus more specifically on the right drill for the specific material. And I am going to be on the lookout for a carbide #7 and ?" drills. And Jerry G., No, I will NOT buy a Drill Doctor! Why? Because my son, who lives locally, has one – that I contributed half (at least) to, so I will take those drills that I abused over to his place. And then use them in the future on wood. Thanks for thinking of it, though, ;) And on the clamp-clips, I made a dozen (started with 16, but we won't go into the ways I only wound up with 12) so at this point I guess I'm good. As for work hardening SS, that sounds like a distinct possibility. Rather than begin with my 1930s era benchtop Delta drill press, I started with my delicate little Foredom drill press, that uses the flex-shaft motor (and the flex-shaft turns into a snake if you push it too hard). I thought I was only making little holes. I'll think better next time. Then Ed and Ian, thanks for the input on identifying stainless steel. That's good information and I will use it to check out what I've got – and then apply the Sharpie to make sure I remember what I have the next time I see fit to try to use it. And finally to all, late last night (at least East Coast time) Charles Fox and I exchanged a series of emails and pictures on how to be sure we have enough 10-32 screws of the right lengths on hand for any purpose. On my approach, I likely got into more detail than necessary. But putting it all together, I decided to combine the write-up and the pictures as a PDF and stick it in the group's Files section. If interested, you can find it there under the heading "10-32 Screws" and download it. So I've got the clamps and I've cut off the required cap screws to the appropriate length. Now all I have to do is turn out a dozen tee-nuts for the new "L" clamps. Regards, Tom Bank ------- aligning a rod for drilling [sherline] Posted by: patbutlerx~xxcomcast.net appraisalservices2000 Date: Fri Apr 18, 2014 9:44 am ((PDT)) I've been making small (5/8") little aluminum disks (.08" thick) that have 6 holes drilled in them. They're used to guide the shroud lines for model rocket parachutes. I initially do a light cut on the lathe to shine up the bar stock, then face the end. What I did in the past is part off a bunch of these little disks before drilling them using my rotary table. I'd much rather drill through a thicker section of bar stock, then slice the disks off. That way, the drilling operation for the six holes can be done at one time. I'm trying to figure out the best way to ensure that the aluminum bar stock is perfectly vertical so that my holes don't shift as I drill down deep into the rod. This project doesn't have to be to tight tolerances, but I like to do things right. Should I just sweep over the top of the rod end that has been faced to make sure its level? Then again, the diameter is so tiny that I wouldn't expect much of a variance over that small of distance. In the past, I've just mounted my 3-jaw chuck in the rotary table and 'assumed' that the bar stock was vertical. ------- Re: aligning a rod for drilling Posted by: "ED MAISEY" holmes_ca_2000x~xxyahoo.com Date: Fri Apr 18, 2014 11:39 am ((PDT)) Do you have a V block, Edmund ------- Re: aligning a rod for drilling Posted by: "Pat B" patbutlerx~xxcomcast.net Date: Fri Apr 18, 2014 6:35 pm ((PDT)) Hi Edmund—yes, I didn’t think about that. I have a complete set that is nearly brand new. That’ll help. Pat ------- Re: aligning a rod for drilling Posted by: "Stan Stocker" skstockerx~xxcomcast.net Date: Fri Apr 18, 2014 1:22 pm ((PDT)) Greetings. If you are using a Sherline rotary table, the chuck adapter is really quite good. If you are using some other make or rotary table Sherline does make an adapter for mounting the chuck to the mill table, rigging one of these on the rotary table will get you pretty darn close to vertical. You could also bore a 5/8 hole in a cylinder mounted to a fixture, then slit it and add a clamp. You are more likely to have issues with the drill wandering than with error due to being slightly off perpendicular/vertical. Peck drilling, using screw machine drills, and holding the drill with as little exposed as possible and still doing the job will help. Straight flute bits drill straighter, but have no chip ejection. If you were drilling with a live spindle on the lathe carriage they would be a good choice. How many of these do you need to make? A couple dozen is one thing, thousands on the other hand would justify making special fixtures to make life easy. Take care, Stan ------- Re: aligning a rod for drilling Posted by: "Pat B" patbutlerx~xxcomcast.net Date: Fri Apr 18, 2014 6:36 pm ((PDT)) Hi Stan — I only need to make 6 of these. So my hope was that I could maintain enough straightness with my drilling so that all of the disks were the same. Pat ------- NOTE TO FILE: The following arose during a conversation in the Oldtools group (not at Yahoo -- see my home page for address). One fellow had bought a can of talcum powder and forgot why. Others suggested some practical uses such as coating file teeth to prevent clogging. ------- Date: Mon, 23 Feb 2015 13:36:18 -0800 From: Michael Suwczinsky Subject: Re: [OldTools] Why did I buy talcum powder? I have used bits of each, salt, talcum and baking soda when drilling high carbon steel (with a post drill, OT Content) the localized heat would result in a thin layer of hardened steel in the hole that I couldn't help breaking bits on. Perusing a metalworking forum provided the idea of just a bit of talc, baking soda and/or salt to give the bit enough bite to cut thru the very thin hardened layer of steel. I stopped cranking so fast on the post drill ------- Three flute drills [atlas_craftsman] Posted by: thehairsx~xxoptilink.us dhlh1984 Date: Wed Jul 8, 2015 8:08 am ((PDT)) I bought about 60 solid carbide drills to grind for tool bits in a diamond style tool holder I'm making. When the drills arrived I found them to be three flute drills. These are the first I've ever seen. Can anyone tell me what this type drill is designed for. David Hair ------- Re: Three flute drills Posted by: paulguenterx~xxatt.net paulguenterx~xxatt.net Date: Wed Jul 8, 2015 8:44 am ((PDT)) 3 flute drills have been around forever. They will drill a more accurate and smoother hole. You also need to buy a drill sharpener for them. GP ------- Re: Three flute drills Posted by: thehairsx~xxoptilink.us dhlh1984 Date: Wed Jul 8, 2015 8:53 am ((PDT)) Morning GP, I've been doing a little research. Looks like then are for aluminum or other soft metals. I was just surprised when I got them that they had the three flutes. For my purpose they will work just fine. I was just after the carbide and at $6.00 and a little shipping for 60 I'm doing fine. David Hair ------- Re: Three flute drills Posted by: "Jon Elson" elsonx~xxpico-systems.com jmelson2 Date: Wed Jul 8, 2015 8:57 am ((PDT)) It can cut faster with three flutes. It may also be less prone to making out-of-round holes. I think the typical 2-flute drills have a tendency to make 3 or 5-lobed holes when they first enter soft workpieces. Jon ------- Re: Three flute drills Posted by: "Charles" xlch58x~xxswbell.net xlch58x~xxswbell.net Date: Wed Jul 8, 2015 10:15 am ((PDT)) They do a better job tracking an existing hole and they leave a better finish and rounder hole. Charles ------- Re: Three flute drills Posted by: jerdalx~xxsbcglobal.net jtiers Date: Wed Jul 8, 2015 9:49 am ((PDT)) There are more than one type. Do they have a regular drill point? If so, then they are just a different drill. Some have a tip more like a reamer, no actual point, and those are for enlarging cored holes in castings. Known as 'core drills" (surprise). Not as much use to you, most likely. Jerry ------- Re: Three flute drills Posted by: paulguenterx~xxatt.net paulguenterx~xxatt.net Date: Wed Jul 8, 2015 10:19 am ((PDT)) I worked with 3 flute and 4 flute drills. Most have a blunt point and are mostly used to enlarge a hole. The flutes must be sharpend properly or you will end up wit a funny hole. Just like 2 flute drills must have equal flutes or you will have a over size or funny hole. 3 and 4 flutes are not core drills. GP ------- Re: Three flute drills Posted by: thehairsx~xxoptilink.us dhlh1984 Date: Wed Jul 8, 2015 4:38 pm ((PDT)) The best I can measure these drills are 135 degree bits. The size is 3/16". I bought them to grind as lathe tool bits to go in a diamond style tool holder I'm working on. Buying carbide this way is way cheaper than buying round tool bit blanks. About 20 of the 60 seem to still be very sharp so I will at least try them in aluminum. David Hair ------- Re: Three flute drills Posted by: "William Burky" wburkysr5x~xxhotmail.com treestump44667 Date: Thu Jul 9, 2015 11:52 am ((PDT)) Yes, these drills are as Jerry pointed out "core drills" and have been used in production for at least 60 years to finish drill cored holes in castings in both 3 and 4 flute configurations. You do not grind the flutes to recondition, but sharpen the lips in a manner similar to resharpening solid reamers. ------- Re: Three flute drills Posted by: paulguenterx~xxatt.net paulguenterx~xxatt.net Date: Thu Jul 9, 2015 5:52 pm ((PDT)) Here is a link that will show you core drills. The 3 and 4 flute drills are not called core drills. http://stores.toolsdirectusa.com/fixed-stand/?gclid=CKSC5-arz8YCFQipa QodFWEBmQ GP ----- Re: Three flute drills Posted by: "Dan Buchanan" db45acpx~xxyahoo.com db45acp Date: Thu Jul 9, 2015 7:37 pm ((PDT)) Here is a link to illustrate an apple core: https://www.flickr.com/photos/free-photos/3389124067 Here is a link to explain core used in manufacturing and casting: https://en.wikipedia.org/wiki/Core_(manufacturing) And here is a link to the Marine Corps http://www.marines.com/home Of the above, only the Marines utilize flutes, but only in the Marine Corps Band. They have 5 flutes, and they, as well as all Marines, are continually being sharpened by running drills. Running drills is never boring because they have drill Sergeants who teach them core values. They are, one might say, the core of the Corps. The Band members do not drink wine from their flutes. Only Champagne. Are you bored? Am I boring you? NEXT: More fun with homophones and homographs. Dan ------- Re: Three flute drills Posted by: "Charles" xlch58x~xxswbell.net xlch58x~xxswbell.net Date: Thu Jul 9, 2015 7:57 pm ((PDT)) I have one of those. Yes, the MACHINE is called a mag drill and sometimes called a core drill. The cutters for them intended for metal however are called annular cutters not "core drill". The cutters intended for concrete and stone are called core drills. This is because the names evolved from two different industries. In metalwork a core drill was meant to enlarge a hole left by a casting core, it was three fluted, some of the old ones basically a simple pyramid shape. There was also a spade bit used for core drilling, likewise called a core drill because it did the same job. In mining, the core drill was an annular cutter. Look at engineering books for as far back as the late 1800's and you will see these different terms used between metal and stone. I am guessing that when the annular cutters were introduced for metal working the tool makers called them by that more technical name to differentiate them from their rock cutters. Of course the other common annular cutter is used for wood and sheet metal and simply called a hole saw. There are two types of three flute drill BITS commonly found. One is in fact called a core drill as discussed here and it is pointless to argue when there are a plethora of catalogs listing it as such from companies that have been at this for over a hundred years though in fact it is ground and cuts more like a reamer than a drill. The other has a different geometry that cuts more like a drill, and is simply a three flute drill for soft materials used in CNC machines. Both are chosen for metal work for the superior quality of the hole shape and finish. Charles ------- Re: .011 diameter bolts [sherline] Posted by: jlkiefferx~xxcharter.net n2562001 Date: Tue Feb 9, 2016 12:44 pm ((PST)) jlkiefferx~xxcharter.net n2562001 wrote: "Construction of the Taps and Dies for making the .009" x 354 TPI nuts and bolts is covered in the Jan/Feb 2008 issue of the Home Shop Machinist." Actually, using a Zeiss loupe can be more efficient that a microscope for general work in many cases. However, not for the following project. When you need a scope you need it. To make a long story short, while doing a machining demonstration for instructors at the NAWCC School of Horology some time back, I was laughingly challenged to do something on a Sherline Lathe. The Challenge was to drill about a .0012" hole in the end of a pivot that was .0028" in diameter. As such at this time it required making the drill. They were joking but I was not, but lucky they were in case I failed. I posted a photo of the drill that I ground on the Sherline Mill mounted in the rotary table under my name. Unfortunately I could not get the camera to clearly focus on the drill itself. In this case it was done at 30 power under a Headstock mounted Microscope. Grinding was done with the tip of a .020" diameter copper pivot charged with 8000 grit diamond and sherlines 10,000 rpm spindle accessory. After untold failures, about 20 hours and three days, I got what you see and was able to drill the hole. While pretty stupid to waste this much time, it was worth every second. Jerry Kieffer ------- Re: .011 diameter bolts Posted by: chieftoolmakerx~xxearthlink.net glicker31 Date: Tue Feb 9, 2016 5:16 pm ((PST)) Mr. Good Buddy, thank you for the very absorbing story. Now, somewhere here, I have a printed brochure of an invention I was part of and the firm I was working for tried to market. It was a very special sensitive drilling attachment to fit any vertical mill. (Not A Sherline.) As a matter of fact, at the time I never had heard of Sherline. Employment was from 1953-1965. If I find it, I will try to post a photo. I mention it because it was developed during our efforts to complete a contract for the U.S. Navy. Something called a Sea Water Battery. For torpedoes. If I do not find the brochure, I will post the story. Best Regards, Jerry G (Glickstein) ------- Re: .011 diameter bolts Posted by: jlkiefferx~xxcharter.net n2562001 Date: Wed Feb 10, 2016 9:52 am ((PST)) Chief: I will have to say that personally, I am not a big fan of commercially available sensitive drill attachments sold today. They are marketed, and perceived to be a method of drilling small holes with a large machine but do not address any of the most important issues involving successful micro drilling. Those issues are minimal drill runout, RPM and controlled feed rate. I suspect that the inventor of these devises had not yet grasp the basics of drilling or was simply attempting to market something. When I teach Micro drilling, I start out with a large heavy drill press, a block of steel and a 1/2" drill. I first demonstrate that if you run the drill at a very high speed, the cutting edge can be damaged either from heat and or friction/work hardening when not cutting metal. Next, it can be shown that when the rpm is lowered to a point of continuous metal cutting under a controlled feed rate, the drilling process is much more efficient and protective of the drill. When using a micro Drill of the same quality, constructed of the same material, drilling in the same type of steel you can expect the same results. For example, if it takes 30 seconds to drill a 1/2" hole 1/2" deep without stress or loads that are great enough to break the drill, you have just perfected a safe Micro drilling procedure under like conditions. So again as an example, if you use a like drill say HSS at .001" diameter, like material, and slow rpm for drill size (Under 2500 RPM) results have proven to be the same. In other words, the feed rate for a .001" drill will be at a consistent rate for a total depth of .001" over 30 seconds to get the same safe results. On the Sherline Lathe, the 1.500" tailstock hand wheel would require that it be moved about .090" outside surface over those 30 seconds for the .001" of depth. While possible, this is not practical for most. However, by using the 2.500" hand wheel this is increased to about .160" over the outside surface. This is far more practical and can be mastered with a hour or two of practice. For the Sherline Mill, WW collets are used to control runout while the "Z" axis is set for "Zero Backlash" or as close as one can get and still have movement. In this case, a 6" or greater disc can be mounted to the "Z" axis hand wheel increasing surface movement up to a half inch for the .001" of depth. This is easily mastered with little to no practice. With the sensitive drill attachments, extended length`s and slip fits increase runout chances that are the death of micro drills. In addition, downward hand pressure offers no protection from a drill digging into the metal at any given time, overloading and often causing breakage. Leadscrew control will not allow a drill to be pulled into the workpiece unless permitted or forced to do so by the operator. When working on very expensive collectable items, failure is not an option so can never place yourself at a disadvantage. Jerry Kieffer ------- Re: .011 diameter bolts Posted by: chieftoolmakerx~xxearthlink.net glicker31 Date: Wed Feb 10, 2016 11:24 am ((PST)) Hi Mr. Good Buddy, thank you for the lengthy dissertation. I have learned a great deal. However, the details and conditions that existed when that particular sensitive drill unit was developed fall somewhat outside of the norm. We took some unusual, extreme measures to ensure our success. I will detail later on. Regards, Jerry G (Glickstein) ------- Peck Drilling [sherline] Posted by: chieftoolmakerx~xxearthlink.net glicker31 Date: Wed Feb 10, 2016 11:24 am ((PST)) Hi Mr. Good Buddy, I meant to ask. In your world of micro drilling, did you ever employ the peck drilling method? Mr. Chief ------- Re: Peck Drilling Posted by: jlkiefferx~xxcharter.net n2562001 Date: Wed Feb 10, 2016 12:28 pm ((PST)) Chief: I should first mention that Sherline's practical drilling limits are in the area of .002"-.003" but with extra time and proper procedure .001" can be safely achieved. The only time I use peck drilling is when for whatever reason I do not take the time to properly setup the machines for the job at hand. While it has worked, but it is not as dependable as the procedure that I outlined or at least by my hand. I should also mention that the National Jet 7A drilling machine is recognized as one of the premiere micro drilling machines ever produced. Its drilling range is listed as .0001" to .015" and was readily available back in the 50`s and 60`s and as far as I know still today by special order. Jerry Kieffer ------- Re: Peck Drilling Posted by: chieftoolmakerx~xxearthlink.net glicker31 Date: Thu Feb 11, 2016 6:14 am ((PST)) Mr. Good Buddy, you have aptly demonstrated your thorough knowledge of the subject. I will attempt to describe the U.S. Navy's Contract we were obligated to pursue. Jerry G (Glickstein) ------- Re: Peck Drilling Posted by: "JERRY G" chieftoolmakerx~xxearthlink.net glicker31 Date: Thu Feb 11, 2016 11:12 pm ((PST)) Hi Mr. Good Buddy, I will be detailing our efforts to fulfill the U.S. Navy contract as I post. For a starter I would like to direct your attention to the photo showing the brochure for the "Slip Chuck". On one side there are three photos. Upper right is me! Still sporting my crew cut because I returned to Yardney Electric Corp in 1953 after being separated from the U.S. Marine Corp. Mr. Chief AKA Sgt Glick *Ret.) USMC 1st Marine Air Wing 1951-1953 (Korea) AKA Jerry G (Glickstein) https://groups.yahoo.com/neo/groups/sherline/photos/albums/174675\ 6360/lightbox/88785264?orderBy=ordinal&sortOrder=asc&photoFilter=\ ALL#zax/88785264 ------- Re: Peck Drilling Posted by: "Ian Newman" ian_newx~xxyahoo.com ian_new Date: Thu Feb 11, 2016 6:02 am ((PST)) Hi,I would second JK's comments re. 'peck drilling' I do a reasonable amount of horological work where it is unusual to drill holes larger than 0.5mm (about 20 thou). I have not found it necessary to use a 'peck drilling' technique -- in fact a consistent feed is kinder to small diameter drills as it is easy to damage sub-millimeter drills through too rapid contact with the bottom of a hole if you use the 'peck' technique. All the best, Ian ------- Re: Peck Drilling Posted by: "Charles Fox" catkinsonfoxx~xxgmail.com cafox513 Date: Thu Feb 11, 2016 8:00 am ((PST)) I’ve done dozens of tiny* holes, spaced equally around a (gulp) curved surface (1/9-scale motorcycle rim, for spokes). I was told by a machinists' group here in SoCal to use consistent feed and the highest speed I could manage. I swapped out the internals of a Sherline mill to give 10,000rpm. My computer ate all my notes — 35 pages — of this project so I can only tell you the size of the holes was less than #60. The rim material was aluminum (6061 as I recall). ------- [sherline] New Photos / A Bag of Tricks / Repaired Adapter Posted by: chieftoolmakerx~xxearthlink.net glicker31 Date: Wed Feb 10, 2016 11:26 am ((PST)) Album; "A Bag of Tricks" Photos show a sensitive drilling unit. Details later. https://groups.yahoo.com/neo/groups/sherline/photos/albums/1746756360/li ghtbox/1992985531 https://groups.yahoo.com/neo/groups/sherline/pho tos/albums/1746756360/lightbox/1992985531?orderBy=ordinal&sortOr der=asc&photoFilter=ALL#zax/1992985531 ------- ------------------------------------------------------------------ This is just one of some 80 files about machining and metalworking and useful workshop subjects that can be read at: http://www.janellestudio.com/metal/index.html ------------------------------------------------------------------