This file on cutters, collets and arbors is a bit of a catch-all, as a conversation on one of these subjects routinely roamed into other areas. The first message deals with threadmills, which is far from common. The rest of this file contains much more everyday-type information. 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 more than 70 additional files on my home page Machining and Metalworking at Home http://www.janellestudio.com/metal/ 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 - 2008 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: Sun, 4 Feb 2001 20:43:26 -0800 From: "Marcus & Eva" Subject: Threadmills: Make your own >Threadmills are available from machine shop supply/ industrial >tooling places. Can be expensive. You can make one from the 'Keyslot' >cutter dremel sells. chuck it in a lathe, and 'grind its' periphery >to 60 degrees included angle. May be easier to make one from scratch >and harden/temper with a torch/oven. Hi All: Did you guys know you can turn high speed steel round blanks on the lathe? I keep seeing exotic recommendations for making cutters out of O1 and other high carbon steels, and hardening them after machining. Try necking down a 1/2" HSS blank (yes you can do it easily on a Sherline), leaving a 0.075 wide bit on the end. (like a small tee slot cutter without the teeth.) Then turn a 30 degree flank on each side, so you end up with a 60 degree included angle disc-shaped end on the blank with say a 0.350 diameter shank 1.0" long. Now grind a single gash across the disc, right on center. Freehand relief grind the underside of the cutter until you are within 0.020" or so of the cutting edge you created when you cut the gash. Stone the relief the rest of the way. This will give you a truly great threadmill (admittedly single point though) which will double in a pinch as a thread boring bar for the lathe. I always make them left hand. That way, when I'm cutting an internal thread, I run the lathe in reverse for a right hand thread. Now the tool will back out of the bore during a cut, so it's way less frightening to cut the thread. I can engage the halfnuts with the thread dial as usual, but I don't have to crap myself about stopping the cut at the right moment to avoid plowing into a shoulder. The cutter will run out into the air. When I run an external thread (if it's a short one) I can use the same tool, feeding it exactly the same way as any other threading tool. For threadmilling, I just chuck the cutter in a 1/2" collet and run the spindle in reverse. I set the start and end point order and the helical code orientation so I get a climb cut with the correct handedness for the finished thread.This means that sometimes I start the thread at the bottom. Climb cutting gives me a better finish and tends to be kinder to the cutter as well. Cheers Marcus ------- Date: Tue, 6 Feb 2001 00:23:02 -0800 From: "Marcus & Eva" Subject: Re: Threadmills: Make your own Hi Alan: The gash removes about a quarter of the circle. One face will be parallel to the long axis and coincident with the center of the blank. The other will be oriented at whatever angle you applied the blank to the grinding wheel. You can grind away as much of the vee shaped disc portion of the cutter as you like: I normally take away the whole back half, and a good portion of the underside. That leaves me with about a quarter circle to grind a relief on, and allows the cutter to sneak into a half inch bore even if it is not perfectly centered. If you want me to send you a picture offline, give me a nudge. Cheers Marcus ------- Date: Thu, 08 Feb 2001 03:49:01 -0000 From: ballendox~xxyahoo.com Subject: Re: re:dremel mount In sherline, on Wed, 07 Feb 2001, Thomas Gilmour wrote: > >What are threadmills used for? "Charlie Lear" wrote:> They're for extherthithing, thilly! Cheerth Charlie Thomas: Threadmills are used for "milling threads". If you look at the drawings posted with your original question, you see the vee shape of the cutter (single vee, or multiple vees). You insert this into a hole, and then move it "out" towards the hole interior surface until the (60 degrees, or other thread shape)vee(s) are cutting; then make a HELICAL motion, where the downward (or upward) motion per revolution is equal to the thread pitch you want to cut. If you have a 'single vee' cutter, you keep cutting circles until the number of threads you want are done. With the multiple vee threadmill, you cut many threads in one "circle" of helical movement. Hope this helps. Ballendo ------- Date: Mon, 5 Feb 2001 11:05:05 -0600 (CST) From: Tom Benedict Subject: Re: Digest Number 267 First off, my apologies for hitting this so late. My home machine has been down for the last few weeks while my wife and I re-arrange our house so my son will have a bedroom by the time he's born. So I haven't read mail for WEEKS. (I'm in withdrawal.) But it has meant for some good time out in the shop. ;) On Mon, 22 Jan 2001, Andrew Werby wrote: > [Thanks for your help, Robin and Tom. I thought of this, but how does > one hold onto these collets while machining them? Robin, you're right- > I'm about at the limit of what I can do without accurate centering. > From Tom's comment, I I think he found it easier to retain the finder > with a set-screw than by slitting it, with which I'd agree, but I'd > appreciate any hints for setting this up.] I used an arbor rather than a collet. I just made up a set of five identical arbors last night, so I can tell you how I did that. When I bought my Taig I bought ten blank arbors. I have two left. Last night I grabbed five, and did the following to all of them: I carefully cleaned the spindle and the back of the arbor, and threaded it on, making sure it seated squarely and solidly (no swarf or junk behind it to throw it off-center). Center-drilled and drilled to one fractional size under 3/8". In retrospect, it probably would've been better to drill through with a smaller drill because my 3/8" drill doesn't have the best tip on it. The cutting edges are sharp, but it doesn't center-cut well. Chucked up a 3/8" reamer in the tailstock, and with the lathe running as slowly as possible, reamed it out to 3/8". (I highly recommend getting a set of reamers if you don't have them. I don't use them every day, but when you need one they're hard to d owithout.) At this point your procedure may vary. SOMEHOW you want to put a threaded hole in the side of the arbor. You can do this with v-blocks and a drill press, or you can do it with a vise and a vertical mill, or you can use the rotary stage on the mill, or... It's up to you. I *do* recommend that you do it as accurately as possible, whatever option you choose. With the five I did last night, I haven't drilled the set-screws yet. The reason I'm making five is that I want to permanently mount all of my end mills in their own arbors. That'll let me mount them so they're all as close to identical height as possible. That way I can swap from an edgefinder to a mill (without set-screws), set the surface height, and change from end mill to end mill (without set-screws), and not have to re-indicate the surface. I'm going to finish them tonight using the rotary stage on the CNC mill. I'm planning on machining a nice grippy surface on the threaded end of the arbor, drill and tap the set-screw hole, and then engrave the size of the mill on them. Not strictly necessary, but why not? Tom ------- From: Tony Jeffree [mailto:tonyx~xxjeffree.co.uk] Sent: Wednesday, January 31, 2001 4:30 PM To: taigtoolsx~xxyahoogroups.com Subject: RE: [taigtools] Plastools Indexable insert holder At 15:56 31/01/01 -0500, you wrote: >Nicholas and Stan, Thanks for your help. Stan, I will try your suggestions >in regards to cutting speeds. I will also try a 221 insert, since that has >a 1/64 nose radius as opposed to the 1/32 radius of the 222. I've had very good results on my Taig using holders that take the smaller Sandvik and Sumitomo inserts, but with rather smaller tip radii than those you mention - 0.1mm and 0.2mm (for comparison, 1/64" is a gnat's hair under 0.4mm). I have tried 0.4mm tip radius inserts & found that they don't work very well on the Taig - tough to get a decent cut, as you described. If you can go down a size or two from 1/64th it might prove worthwhile. Regards, Tony ------- Date: Fri, 9 Feb 2001 21:47:25 -0800 From: "Kory Hamzeh" Subject: RE: Endmill in collet? > Can I hold an endmill in a collet? I've heard it done that way, but I've never tried it. Here are plans for an easy to build end mill holder: http://home.rmci.net/deanw/shop.html. Kory ------- Date: Sat, 10 Feb 2001 05:50:01 -0000 From: "tauseef" Subject: Re: Endmill in collet? Hey Eric: Yeah you can use a collet to hold your endmill as long as it's 1/4" and you have the drawbolt for it. You don't need the "endmill holder" like the 3/8" one sherline sells. I use a 1/8" and 3/16" collet often. Endmill holders and collets are fine but don't use a chuck for holding them. Also try to keep the endmill as short as possibe to keep it rigid (can cut the endmill in half with a dremel cutoff wheel if its double sided and material allows--keep the endmill cool). later tauseef ------- Date: Sat, 10 Feb 2001 10:10:43 -0800 From: "Kory Hamzeh" Subject: RE: Re: Endmill in collet? A collet WILL work. As a matter of fact, holding an end mill in a collect will give you more accurate results because end mill holders have a much larger run-out than collects (almost none). However, if you make aggressive cuts with the end mill in a collect holder, you can cause the collect to spin and possibly crack it. Like I said in the original reply, I've never used a collect to hold an end mill, but I've heard other have and some have spun the collect and cracked it. The set screw in the end mill holder hold the end mill in place. Kory ------- Date: Sun, 11 Feb 2001 04:27:50 -0000 From: "tauseef" Subject: Re: Endmill in collet? Hi kory and dean thanks for the info and thank you Dean for the address again..I really like your pages! Interesting stuff! I also made a cutoff tool holder but really like yours also. Kory, I would think one must be really machining aggressivly as you mentioned to crack the sherline collet! I would think the endmill would crack first. Spining it, maybe, but they are held in very tightly with little pressure from the drawbolt. Personally, I use them most of the time and like them more than the 3/8" holder. They are much smaller, go into the spindle and the only thing sticking out is the short endmill. The only thing that can be a problem is get them out but a samll tap on the drawbolt is usually only needed. Each has its purpose but if ever need give a collet a try you might like them. later tauseef ------- Date: Tue, 13 Feb 2001 10:02:40 -0600 (CST) From: Tom Benedict Subject: Re: Reducing 1/2" HSS shank On Tue, 13 Feb 2001, Jim Lewis wrote: > Has anyone turned down a HSS shank using a carbide cutter on the Taig > lathe? It seems like pushing the limits of the Taig and I don't want > to break anything. Also not sure how deep to cut each pass. The > purpose is to adapt a tool to the mill which is limited to 1/4" > shanks, unless someone has a better method. Thanks. When you say HSS, do you mean a hardened high speed steel shank? If so, there are a couple of ways I might tackle something like that: First, I'd look at the feasibility of using a blank arbor to make a 1/2" tool arbor. I made one of these for a third-party fly cutter, and it's worked great. (I since decided it would've been only slightly more involved to make the entire fly cutter out of an arbor, something I'm planning on doing once I get some projects finished.) If it looked like I had no choice but to cut the shank down on the lathe, I'd try to remove as much material as I possibly could in some other way. I've got a bench grinder that would get rid of the bulk of the material, leaving only a little to remove to get the 1/2" shank down to 1/4". Failing that a Dremel, Foredom, or other grinder would work, and they'd give me finer control. Once it was roughed down to size, I'd see if I *could* cut it. If it's hardened steel, I'd be inclined to use a toolpost grinder on the lathe to get it down to 1/4". (Be sure to cover as much of your lathe as you possibly can when you're grinding! Grit's NASTY to lathe ways.) If it was case-hardened, the earlier grinding step would have cut past the hardened part, and it might be able to be turned using normal tools. In the end, though, I'd be concerned about having taken a tool that the manufacturer believed to warrant a 1/2" shank, and reduced it by a factor of 4 in cross-section, to a 1/4" shank. Given the choice I'd make an arbor for it. What tool is this, if you don't mind my asking? Tom ------- Date: Tue, 13 Feb 2001 15:30:25 -0000 From: "Jim Lewis" Subject: Re: Reducing 1/2" HSS shank Hi Tom, thanks for your detailed reply. > When you say HSS, do you mean a hardened high speed steel shank? I meant High Speed Steel - I don't know exactly what it is. > First, I'd look at the feasibility of using a blank arbor to make a > 1/2" tool arbor. I made one of these for a third-party fly cutter, > and it's worked great. Any pix - I'm not sure how it would work. Just a 1/2" hole with a set screw? Taig's arbors are hollow so I don't see how it would be done. > What tool is this, if you don't mind my asking? 3/16 edge grooving tool - looks like tiny radial saw blade. I'm only cutting alum/plastic with it. Jim ------- Date: Tue, 13 Feb 2001 16:10:25 +0000 From: Tony Jeffree Subject: Re: Re: Reducing 1/2" HSS shank >3/16 edge grooving tool - looks like tiny radial saw blade. I'm only >cutting alum/plastic with it. The "blank arbor" that Tom mentions is basically a piece of 1" diam steel stock, already bored & tapped at one end to fit the Taig spindle nose (3/4-16 thread). The other end is unmachined. Taig sell them for a few bucks each - probably the single most versatile accessory that they make, as there is almost no end to the range of arbors and holders that can be made from them. The blank arbors are made from free cutting steel - very easy to machine. To make up a tool holder of the kind Tom is talking about, what you do is fit a blank arbor on the nose of a Taig lathe & then bore it to fit the tool shank (1/2" in your case), then cross-drill & tap the arbor to take a set screw that will hold the tool in the arbor. Ideally, the boring of the 1/2" hole should be done by axial drilling an undersize hole and then finishing off with a boring bar or a reamer - it is very difficult (if not impossible) to accurately drill a 1/2" hole on axis & to size just using twist drills. The Taig lathe and mill both have the same nose thread, so the completed tool holder can be used on the mill. I have done this successfully for holding 1/2" arbor flycutters and dovetail cutters. Alternatively, why not start from a piece of 1/4" drill rod & machine yourself a cutter instead? Much easier to machine than HSS & can be hardened after machining. Should be just fine for Alu/Plastic cutting. Regards, Tony ------- Date: Wed, 14 Feb 2001 02:19:01 -0000 From: tgilmourx~xxiname.com Subject: Re: Endmill in collet? Eric: If you want to make endmill holders [for Sherline], Taig Tools sells blank arbors that look like the endmill holders that Sherline sell. They have the same threading as the Sherline spindle, but you have to cut a little off the threaded end using the lathe so they screw onto the spindle far enough. You can screw these onto your spindle and then drill and ream for whatever size needed. They're made of leaded steel so they cut very easily. Taig's URL is taigtools.com and the part is #1130 under 'accessories'. Best of all, they only cost $1.75. I bought a half dozen. Tom ------- Date: Wed, 14 Feb 2001 09:21:36 -0800 From: "Nicholas Carter and Felice Luftschein" Subject: RE: Re: Endmill in collet? The 1130 is tapped on the end for a #8(?) screw and has a supplied washer. makes it that much easier to make slitting saw arbors, etc. I tend to use the 1132 as I am cheap, and it's not that hard to tap the end. They do machine beautifully. I used them successfully on the Sherline mill, but as others have noted you have to remove a section on the end because of the difference between the Taig and Sherline spindles. If you look on my "picture" page http://www.casco.net/~felice/picture.html there should be many pictures (scattered throughout) of different accessories made with the blank arbor. I even made a boring head from one. See our web pages http://www.casco.net/~felice ------- Date: Thu, 15 Feb 2001 04:11:05 -0000 From: lasernerdx~xxhotmail.com Subject: Re: Reducing 1/2" HSS shank I agree. Tool bits are made to be used _as_is_. It would be _far_ simpler (no, I don't think "simpler" is a word, but too bad!) and more practical to make the 1/2" tool holder. I recently made a 3/8" and a 1/2" arbor for my mill, and they took less than 30 min each. Total runout on the 3/8" was +/- 0.001, IIRC and that was using a simple reamer. Regards, Robin ------- Date: Fri, 16 Feb 2001 02:46:26 -0000 From: lasernerdx~xxhotmail.com Subject: Re: Need some help... Jeff: The endmill you received from Nick is made to cut using both the bottom surface, and side surface. It is not tapered, but rather it is straight. As for your comment on how it doesn't look as though it's' meant to produce precise surfaces, I don't understand how you came to this conclusion. It should be a 2 fluted double-ended 0.125" high-speed steel endmill from England. If so, I can assure you it's meant for precise work (I can cut to within about 0.0003" with its 3/16" cousin on my Taig mill). In your last message in reply to Nick, you mentioned a 2" diameter cutter with a 1/2" arbor hole in the middle. This would suggest you have picked out a cutter for a horizontal mill. I would imagin the price for this cutter was quite heafty. This is not what you want. For all purpose cutting, you would want a 2-fluted center-cutting endmill made of high-speed steel, and TiN coated if you can afford it. Idealy, it should be made in the USA, England, Germany, Japan, Switzerland, etc. The inexpensive endmills come from China, Poland, etc and will not last as long as the more expensive ones mentioned above. The most common shank sizes for endmills used on the Taig would be 1/4", 3/8" and 1/2". I would suggest a 3/8" shank size, as this will limit the size of the tool which will reduce the cutting pressure on your machine. A tool with a 1/2" shank is getting pretty big for the Taig mill, and usually, there's no need for such a cutter. The cutter diameter really depends on you. The larger the diameter, the more stable the cutter. However, the price of the cutter does tend to increase as the diameter increases. Also, if you will be using the side of the cutter to cut out more complex shapes (and not just facing) you will be obviously left with a larger radius with a larger cutter. The flute length is also important, as you've already discovered. The longer the flutes, the deeper the cut you can take (that is, you can go deeper on the Z axis while facing with the side of the cutter). However, the longer the flutes, the less stable the cutter is, so you cannot take as heavy cuts. The material of the endmill is not very important at this stage of the game. If you're cutting plastic, aluminum and mild steel for hobby purposes, the HSS uncoated endmills will do fine. If you want your tool to last a bit longer, spend a couple bucks more and get the TiN coated endmill. If you'll be cutting titanium or other very hard exotic materials, you may want to go with indexable or brazed carbide tools, or even solid carbide, although these are very expensive. There is also cobalt steel, and it lies somewhere in between HSS and carbide. Most hobbyists use HSS endmills. The number of flutes doesn't really matter for many applications. However, the more flutes, the faster you can cut, and I believe they're more expensive. Most two fluted endmills are center cutting which means you can plung your cutter like a drill bit (with no pilot hole) and then begin to cut. Some four fluted endmills have this, but not all. I would suggest you get an endmill with center cutting capability. Roughing endmills are _very_ expensive and are generally suited to industrial applications where being able to cut at 500% the speed of HSS saves time and money. For an amateur, they're really a waste of money. Hope this helps, Robin ------- Date: Thu, 15 Feb 2001 22:51:20 -0800 From: "Nicholas Carter and Felice Luftschein" Subject: Re: Re: Need some help... > Roughing endmills are _very_ expensive and are generally suited to > industrial applications where being able to cut at 500% the speed of > HSS saves time and money. For an amateur, they're really a waste of money. Robin, I disagree heartily! I use a 3/8" and 5/16" roughing endmills often on my Taig mill - I find that the advantage of the roughing endmill is less of a power requirement for the cut - I can take a 1/2" deep pass in Al with the roughing endmill on the Taig mill - something I never thought possible. The chips are smaller and the tool doesn't load up as much. See our web pages http://www.casco.net/~felice ------- Date: Sat, 17 Feb 2001 14:11:24 -0500 From: Tom Bank Subject: Question for Craig Libuse: Cutting Lathe Bits Craig, one of the crafts on which we in this hobby judge ourselves is the ability to turn out a decent lathe tool bit. When I bought my Sherline lathe some years ago I also got the set of high speed tool bits you offer and a bunch of blanks. I have kept the set of Sherline bits pristine as examples of what my attempts should look like, but try as I might, the ground surfaces of my bits looked more like the sides of Indian arrow heads than the flawlessly smooth surfaces of the examples. The other evening, though, I needed a special shape bit with a curved front. My grinding/sanding/polishing station was not set up with the white aluminum oxide wheel, but rather had a 4" wide aluminum oxide sanding belt on an accessory attachment, so to rush the job through I flipped the switch and applied the bit to the belt. I was amazed by the result. The bit came out with smooth planes and a graceful curve across the front face. It also seemed that the bit stayed cooler as I was working on it. After finishing the first bit and a second that I had been meaning to make, I went back and prettied up a half dozen older bits to get rid of the Hiawatha look. Then when I got up today, I spent the whole morning searching my shop for a never-used attachment that promises to turn my band saw into a narrow belt sander, which I finally found. With it I should be able to cut lathe boring bits and inside threading tools (that at least look) like a master. So now to the question: When making lathe bits at Sherline, do your staff members use a grinding wheel or a belt? And do you have a CNC set-up to cut bits identically or do you free-form them using infinite experience as your guide? I am interested in knowing whether I stumbled onto a common practice or just a method for an amateur like myself to turn out acceptable counterfeits of the masters' products. Regards, Tom Bank ------- Date: Sat, 17 Feb 2001 21:50:48 -0500 From: "Rich D." Subject: Re: Question for Craig Libuse: Cutting Lathe Bits One more item. If you are going to spend some tens of bucks on a good belt sander and good belts, you may as well spend it on one thing. A diamond wheel. This replaces the usual al-oxide bench grinder wheel (same speed) and cuts HSS, HSS+cobalt and carbides all day long. Glendo and probly others sell these nickle plated diamond imbedded high speed wheels. There are low speed flat disc wheels (laps) also. I use them all along with the white toolmakers wheels. For catalogs: http://www.glendo.com/AF/afpage1.html www.riogrande.com ------- Date: Tue, 20 Feb 2001 15:51:10 -0500 From: Tom Bank Subject: Re: How to cut T-slots Jerry Jankura wrote: >>I'm planning on making some T-Slots in a piece of aluminum that I want to match those in the Sherline Equipment. I know that the method is to make a straight groove in the metal using a standard 1/4 inch end mill. Once this groove is made, the next step is to use a tool that has a smaller shaft and is able to cut the lower part of the groove wall. What is the tool that I want to use called, and where can it be purchased? << Jerry: It may depend on how much of this T-slot cutting you want to do. I have done limited amounts using a Dremel #199 wheel. I may have preceded that tip with some passes with a #198. It took passes at several heights going down first one side of the 1/4" slot, then over and back following the other wall of the slot. Cheap, since I had the Dremel cutters, but you need to lock the Z axis to get an even cut. The new Sherline Z-axis lock is very handy for this. The took we would like to have is a T-slot cutter, but they usually come with a 1/2" shank. I saw some smaller shanked T-slot cutters at Cabin Fever last month, but couldn't remember what size Sherline uses. Does anyone know of a source for 3/8" shank .395 (dia.) X .095 (wide) T-slot cutters? Again, a second cutter of .300-.325 diameter would help by reducing the amount of metal that was being dug out of the slot in a given pass. ------- Date: Tue, 20 Feb 2001 17:31:22 -0500 From: ron ginger Subject: Re: Re: How to cut T-slots Make one. A piece of 1/2" drill rod 3 ft long cost about $7, will make a couple dozen cutters. Turn the cuttter to shape, mill the teeth, polish it well, harden it with a propane torch, tempter it back to a straw color. Hone the edges with a stone, or grind them if you are equipped. You really need to learn to make cutters- its one of the realy exciting parts of metal work. I ordered one of each fractional size drill rods, up to 1/2". Mark each rod with a tape flag with its size so you can find them, and so you can remember its drill rod stock and not just common steel. This can make great reamers, boring tools, all manner of special cutters. ron ginger ------- Date: Tue, 20 Feb 2001 21:56:23 -0000 From: wjw2000x~xxhotmail.com Subject: Re: How to cut T-slots You can find pictures of the Sherline T-slot cutter I made, and the results at the following site: http://www.geocities.com/wjw2000athotmaildotcom/projects.html ------- From: gavin.Eyrex~xxrsl.com Reply-To: sherlinex~xxyahoogroups.com To: sherlinex~xxyahoogroups.com Subject: [sherline] Sharpening Tools Date: Wed, 21 Feb 2001 14:28:19 -0000 I recently started using steel as the medium I am working in rather than brass. In brass tool life and sharpness wasn't an issue - it seemed that carbide end mill would last forever. The same isnt true in steel - and the mills do loose their edges fairly swiftly. What do I need to purchase to be able to successfully sharpen tools. Please bear in mind that I am an absolute novice when it comes to machining - any assumption of a base level of knowledge would be wrong :-) Thanks Gavin Eyre ------- Hi Gavin, I have been cutting steel, drill rod, 303 stainless, brass and whatever for a long time with HSS with very little need for sharpening. I would suspect you are not using proper speeds and feeds or lubricant. Running an end mill too fast will burn up the edge. As for sharpening there are the Tinker and Quorn cutter grinders as well as others that have been published in the Home Shop Machinist. For the difficulty, time and expense involved to build one it is more economical just to buy new end mills. I have had the Tinker for years in kit form, unbuilt. (Someday I'll build it.) I have my large end mills sent to a commercial grind shop because they are cheaper to sharpen than replace. With smaller end mills, I think it is cheaper to replace smaller mills than to send out. Regards from Les Grenz & the Queen City of the Rockies. AWI 18150 NAWCC 82932 ------- Date: Fri, 23 Feb 2001 09:26:01 -0000 From: ssmithx~xxserena.com Subject: Re: Small Collets for Sherline Lathe In sherline: > I'm trying to thread (0-80) the end of some .061 stainless steel > shafting using a Sherline 1/16" collet in the headstock, and a die > holder in the tailstock. The shafting keeps turning it the collet > when trying to thread. Does anyone have another source for small > collets that will fix the Sherline lathe. I looking for collets that > are 1/16" and smaller. Bob I have made a 1/16 collet adapter for my 1/8 mill collet. Mill collets have more holding power. I used 1/8 steel rod, drilled the 1/16 hole using my lathe, used a .010 slitting saw to make the 120 degree cuts part way down the rod. You could also make a .061 holder out of larger rod using set screws to hold the rod in the .061 hole of the larger rod and holding the larger rod in the lathe with a collet or chuck. You could also make one out a TAIG blank arbor (#1130 or #1132) which also fits the Sherline spendle, drilling a .061 hole and adding set screws. ------- Date: Mon, 26 Feb 2001 21:49:03 -0700 From: "Les Grenz" Subject: Re: Mini-Lathe Tooling System For years I have used what I think is the greatest tooling system since sliced bread for the mini lathes. I have used them for 20 years. First on a Unimat 3, then on the Sherline. The tooling is presently sold by Travers. I am taking the information from a 1997/98 catalog. It is called the Unique Tooling System by TTC. It consists of a left and right 5/16" shank tool holder, mini boring bar and cut off tool. The holders use HSS or C5 carbide inserts which are about 2" long. A quick grind on the end of the tool, and a lick and a swipe on the side gives an excellent cutting edge. The insert also has a built in chip breaker along its entire length. No more worries about rake angles. The insert is only 1/8" wide which is ideal for micromachining. I cut every thing from brass to stainless. And that is my not so humble opinion. It is: http://www.travers.com Try them, you'll like them and they are relatively inexpensive. Regards from Les Grenz & the Queen City of the Rockies. AWI 18150 NAWCC 82932 ------- Date: Fri, 2 Mar 2001 21:22:23 -0500 From: "Marshall Pharoah" Subject: Re: Re: 55 degree dovetails > > Several people in the past have looked for 55 degree dovetail > > cutters (unsuccessfully). Dont the carbide inserts that Sherline > > reccomends for the lathe have a 55degree angle? Shouldn't be > > too hard to make up a special cutter similar to the carbide fly > > cutter for the mill. Marshall > The one way I was thinking of doing this is to use a 45 degree > dovetail cutter first, then tilt the work piece 10 degrees and make > some more passes with the 45 dovetail. Setting the height and > position of the cutter would take some care. Steve That would do it. If I ever have to do one, I'll fire up the South Bend shaper. Another way would be to grind a cutter for the Sherline gear cutter or possibly the fly cutter. But I think it would be fairly simple to turn a 55 degree taper on a #1 mt blank, and then cut out a wedge for the carbide insert. I think they grind those fairly accurately. Marshall ------- Date: Sat, 03 Mar 2001 03:17:23 -0000 From: wjw2000x~xxhotmail.com Subject: Re: 55 degree dovetails Actually, the lathe bed angle is something like 55-1/2 degrees. Check out the Sherline web site for their standard dimensions. I don't think that they have actually adopted 55-1/2 degrees, but rather adjust their machines to match some samples of the early production parts. If you need to match the lathe bed angles "exactly", perhaps it would be better to "scrape in" the matching part, or somehow adjust the angle of your cutting tool until the part picks up an even coating of marking medium from the lathe bed. Trial and error. ------- Date: Sat, 03 Mar 2001 15:01:45 -0500 From: Tom Bank Subject: Re: Re: 55 degree dovetails The way I cut the 55 degree angle was with a 45 degree dovetail cutter. I set the work piece in my vise, front to back on the mill table. Then I angled the milling head 10 degrees, cutting on the Y -axis, and proceeded left to right on the X-axis until the cut was as deep as I needed. As for the half a degree (55-1/2 degrees), when I lock on, it grips. I don't know whether my piece is over or under 55 degrees. I don't know how much it takes to cause problems. Regards, Tom ------- Date: Wed, 07 Mar 2001 19:51:26 -0500 From: Thomas Gilmour Subject: Re: Half Inch Mill Chuck Jerry: Taig has blank arbors that are threaded and fit on the Sherline. They look like the Sherline 3/8" end mill holder, only longer and with no hole through the business end. You do have to face off .2" to .3" from the threaded end so enough of the threads engage on the spindle. Then you can drill and bore for whatever you need. They're made of leaded steel and machine very easily. I believe the part # is 1132 and they only cost $1.75 each! They do list more than one blank arbor but the other one I believe has had additional work done to it and it costs $2.95. Their site is www.taigtools.com and I think they're listed under accessories. Tom ------- Date: Wed, 7 Mar 2001 23:12:46 -0500 From: "John Guenther" Subject: RE: Half Inch Mill Chuck I bored out a standard Sherline 3/8" end mill adapter about 2 years ago. I use it with Woodruff Key Seat cutters in making T-Slots for model airplane plug in wing connectors and other assorted items. It works great, you have to be careful about the size of the cutter and the speed and feed you use. Just bore it out to a couple of thou under .500 and ream to .500. I did mine on a Sherline 4000 lathe but I am sure there are other ways to get the job done. John Guenther ------- Date: Thu, 8 Mar 2001 01:00:19 -0600 From: "Al Lenz" Subject: RE: Half Inch Mill Chuck Jerry, I'm not Tom but I just received some of the Taig arbors and happened to have them in front of me. They are 1" stock 2" long. The threaded end is bored 1" deep. You will need to trim off approx .200 (there is a counterbore on the threaded end that needs to be removed). With that and the .300 length of the Sherline spindle that will protrude into the threaded end, that will leave 1.5" total of which 1.0" will be solid material. Al PS I got mine from Nicholas Carter, good service and nice to deal with. http://www.casco.net/~felice ------- Date: Thu, 08 Mar 2001 09:45:19 -0000 From: ssmithx~xxserena.com Subject: Re: Half Inch Mill Chuck I also have just received my Taig arbors. I 2 each of both the 1130 and 1132, The 1130 is drilled and taped for 8-32 and includes a Cap and the 8-32 cap screw to hold it on ready to be turned as saw arbor. I made a 1/2 mill holder out of one of the 1132. I only removed .150 from the thread end because the threads start at about .190 in. I center drilled and used a #1 then #N and then a #Z drill on my lathe (a compact 5). I then put the arbor on my Sherline mill, put a boring tool in my 4 jaw check and mounted it on the table and carefully bored out the hole to 1/2 inch. My American Standard #303 Woodruff cutter slides right in with no play. The arbor itself has a lot of runout but because I bored the hole with it mounted on the spindal the hole is close to true. I have not put in the set screw or the tommy bar hole yet. The #303 Woodruff cutter is 3/8 dia and 3/32 face and it just fits into the slot in the bed. I have not cut a slot with it yet. You need to first make a 1/4 slot with an end mill and then run in the Woodruff cutter. [Next para added afterwards to a follow-up comment below.] The boring operation was done on the head stock, The small run out may be due to small missalignment when remounting the arbor after removing it and may change depending on how tight you screw it on. The runout is only .0005 Steve ------- Date: Thu, 8 Mar 2001 09:34:07 -0500 From: "Carol & Jerry Jankura" Subject: RE: Re: Half Inch Mill Chuck Steve: I assume that the run out is small enough that it wouldn't make any sense to take a cut with the arbor mounted on the headstock. Right now, I need the T-Slot on a piece of metal that I'm machining to make a gauge for my woodworking equipment. This will look something like the TS-Aligner Jr, if you're familiar with that tool. I'm glad to hear that the #303 cutter makes a good match for the Sherline products. Too bad that Sherline doesn't offer some of these cutters with shanks that would better fit their equipment. On the other hand, it's a good learning experience for those of us who are just learning to use our equipment. I'm having a blast with it. Thanks to you, and to the others on the list who have provided answers to this and several other questions. The list is a really good resource. Jerry Jankura Strongsville, Ohio ------- Date: Wed, 07 Mar 2001 14:56:09 +0000 From: Tony Jeffree Subject: Re: Blank Arbors >When I bought my lathe, I ordered a blank arbor. It was just a >cylindrical hunk of steel with a hole drilled and threaded to match the >spindle on one end. >Not too long ago, I ordered some more from a different vendor. These came >with a flat disk attached to the other end with a small hex-end screw. >Something like I would have expected the slitting-saw arbor to look like, >except that I would have expected a 1/2" shoulder to match the saw center >hole, and there isn't any such thing. >Have the blank arbors changed? Or did they send me the wrong thing? >(The package was labelled blank arbors, and they'll work fine as they are, >unless I ever need to make one with a very small hole drilled on center, >and anything I'm likely to do that would need that would probably be >built on a blank collet.) The short answer is that there are 2 different part numbers that both have the description "blank arbor". When I order them in the UK, I get the second version that you describe. I don't think the UK importer actually stocks both varieties. Looking at Nick Carter's price list, there are actually 4 varieties of arbor that will thread onto the nose, each of which can be pressed into service/re-machined for other uses: 1110 Slitting saw arbor $4.90 1120 Grinding wheel arbor $5.25 1130 Blank arbor $2.95 1132 Blank arbor $1.75 I believe that 1130 is the one that has the disc/screw fitted. 1132 is the truly blank, blank arbor, unmachined apart from the 3/4-16 thread for the spindle at one end. Regards, Tony ------- Date: Thu, 08 Mar 2001 09:51:11 +0000 From: Tony Jeffree Subject: Re: Blank Arbors >I noticed the grinding arbor listed in Nick's catalogue only the other >day - what does *this* wee beastie look like? It has a threaded spindle at the business end, looks like 3/8" & about an inch long. It comes with a pair of washers - one goes behind the grinding wheel, the other is very thick & has the same 3/8" thread as the spindle, which clamps the wheel. They sell a set of small grinding wheels to go with it - very inexpensive if I recall. Not made use of mine yet, but it has always struck me that the Taig might form the basis of a simple tool & cutter grinder. I plan to treat myself to a new lathe at some point (mine has seen a bit of wear/abuse!) & press the old one into service as a cutter grinder. Regards, Tony ------- Date: Mon, 26 Mar 2001 20:19:30 -0800 From: "Dave Engels" Subject: Making Gears With A Fly Cutter I'm missing one of the gears for my 6x18 Craftsman, an decided rather than pay $25 to Clausing I'd try to make one out of aluminum. I just wanted to see if I could do it. So far I've made the holding jig, and a 'dividing head' that uses one of the gears I do have whose teeth are an even multiple of the gear I'm going to make. So far so good. Now the difficulty starts, as I'm trying to grind a fly cutter with a 24DP 14.5 degree pressure angle involute for shaping the gear teeth. Tried grinding a 1/4" HSS cutter on my grinding wheel, but that was way too fast acting for fine work, and I was nervous putting my face so close to the wheel to do some accurate shaping. This next worked very well.......I took a little diamond wheel for my Dremel moto-tool (swap meet, $2). It's about an inch in diameter, and really cut the HSS bit easily. I slowed the Dremel down so I could make fine cuts, and it is really working nicely. I intend to always shape my cutters this way whenever I've got a special shaped tool to grind. But, I need some advice. Even with the very delicate grinding I get by using the Dremel/diamond wheel, I'm having a heckuva time getting the fly cutter bit to be the right shape. The fly cutter has to have the exact shape of the gear tooth I'm trying to cut, or else it will trash the gears it mates with on the lathe. I could try to find a milling machine gear cutter of the right DP and PA, that is my next step if I do a better job grinding the fly cutter bit. Anyone have any ideas or experience that would help (or a 24DP 14.5 degree PA involute gear cutter for sale, reasonable)? Many thanks, Dave Engels ------- Date: Mon, 26 Mar 2001 23:11:53 -0600 From: "J Tiers" Subject: Re: Making Cutters (was fly cutter) Short of a tool and cutter grinder, I found that a Delta disc/belt sander is great for this. The 1" belt and 5" disc is what I got, for a mere $70 at Lowe's. I suggest making sure it is a Taiwan, not a China origin, as they seem to be better. Disc side has an angle holder which is reasonable for most use. I am making some jigs for common angles as I need them. For 14.5 degrees you will probably want to make a custom jig. Various grits from 50 to about 320 are available for disc and belt. I found that fine on the belt and coarse on the disc was best. The disc is the best for bulk removal and shaping. Jerry ------- Date: Mon, 26 Mar 2001 23:02:05 -0500 From: Stan Stocker Subject: Re: Re: Questions for the gurus Jim: You can always chuck a pin vise in a four jaw, or perhaps even a three jaw. Some of the Starrett pin vises have smooth areas you can grip on, as do some of the old Generals. You may even be able to use the knurled ones with sufficient accuracy, or make a holder for your pin vise collets from a blank arbor. I haven't done this, as I just thought of it, but it seems like a do-able task. At least we know you have the ability to cut fine threads as needed! You could make a collet from a blank collet, or do a slit insert to go into one of the standard size collets. Poking a 1/16 hole down the center of a bit of 1/8 brass rod and slitting it lengthwise is easy enough, and would be my first approach assuming you have the standard collet set already. Using a larger bit of rod and turning it down to 1/8, leaving a shoulder to keep the insert from slipping back into the collet would be even nicer. If you only need to do a few pieces and can dedicate a chuck to the work for the duration you could make a small collet with a piece of stock held in the three jaw. Drill, ream, slit with a jewelers saw, and clamp with a small hose clamp. If you mark the collet to allow matching it back to the orientation in which it was made you may get adequate repeatability. A good quality drill chuck on the headstock adapter to hold a chuck may also give you the accuracy you need. You might be able to ream a 1/16 opening in the soft jaws with them closed all the way down. If you need a thou TIR, there are lots of methods. A tenth can be tough. If you have to do lots of small work, and can justify $350 or so, get a spare headstock with a WW spindle and a set of WW collets. Individual WW collets are also available should you want to reduce the cost of getting into WW collets. A spare complete Taig setup for WW would be even nicer! Stan ------- Date: Wed, 28 Mar 2001 00:39:41 EST From: catboat15x~xxaol.com Subject: Re: Making Gears With A Fly Cutter engelsdax~xxhome.com writes: > Anyone have any ideas or experience that would help (or a 24DP 14.5 degree > PA involute gear cutter for sale, reasonable)? One way to make a cutter for gear teeth, used by clock makers, is to turn it on your lathe. Use a piece of drill rod and turn the end to the shape of the space between the gears. (This is much easier than trying to grind the shape on a square piece of tool steel.) Then mill, file, chew or whatever half the diameter off the working end, harden, temper, stone smooth and away you go. John Meacham High Desert of California, Palmdale, Littlerock ------- Date: Wed, 28 Mar 2001 11:08:56 -0500 From: Larry Richter Subject: Re: Making Collets - sawing ajkdfwx~xxaol.com wrote: >For the most part I use my Taig to turn small parts for my scale boats. I >make extensive use of the collet set that came with the lathe, however there >have been times I needed a particular size which wasn't included. I have >blank collets and the Taig slitting saw ... the drilling and reaming seem >straightforward but I'm truly puzzled as to how to hold the collet while >machining the slits. Call it lack of imagination but I've been over it a >dozen times in my head but the answer eludes me ... If the saw is turning >perpendicular to the bed, how can the collet be secured and slit? Also, at >what speed should the saw be turning to make these slits? Any help is truly >appreciated ... Thanks. AJ This may not be help, it may be only gossip. But. Most power cutting operations have a hand equivalent. Power machining is the recent addition, actually. It rules because it is Soo MUUCH BETTTER, but the hand operations, if you pick up the skills, are surprisingly simple and versatile, and many beautiful and astounding things have been made by sawing, filing, and chiseling. The last post on making collets mentioned the jeweler's saw, which is one of these old tools. It probably needs to be better described. It is like a coping saw, in general, and is a lot like a cabinet makers fret saw. It is a C-Clamp shaped frame, usually with one adjustable joint in the frame, vertically adjustable, and a pair of clamps at the tips to hold the ends of a tiny blade that is made of very highly refined steel (or ought to be-- there are useless cheap blades by the million). The blades come in a wide range of sizes and of almost invisible tooth counts. Once you master the mysterious skill required, to wit, you never put any pressure on the blade but simply move it up and down and let the sharpness do the job, you can cut almost anything to almost any shape. You can cut your collet slit with one of these while thinking of lunch, or something else good, and not have to worry about the set up. But it isn't modern. Saw brand that is best for the money is generic German. If you find stock on the shelf that says "West Germany" you are really in. Get best quality Swiss blades if you want to be sure of consistency, or the various laser brand blades from Rio Grande Jewelers supply in New Mexico. Rio Grande won't deal with everyone like they used to, though. Other stuff can be good, but I got tired of having every package of blades be a test case, and settled on Swiss (skys, lotus, others) and laser gold. Rio has Swiss files that are like a dream, also. ------- Date: Wed, 28 Mar 2001 13:30:43 -0500 From: "Rich D." Subject: Re: Making Collets AJ, this is one of those problems that "makes a machinist". Think of indexing. Think of holding. 3 slots, easy. Lock a hex head screw into the drawbar end of the collet. The head is the indexer. Hold the collet in the vise in a split sleeve or block such that the parallel sides of the screw head also contact the vise. Orientation of all of this depends on your machine, tooling, etc. Center the slitting saw on the collet and cut a slot on the top. Rotate (index) the collet to the next pair of flats and cut again. The collet has to be held well back on the shank to stay clear of the saw blade as well as not collapse the collet as it's cut. No climb milling allowed. Good luck. Rich D. ------- Date: Wed, 28 Mar 2001 19:43:54 +0100 From: Tony Jeffree Subject: Re: Making Collets Rich - The Taig collets don't use a drawbar & are split from both ends (4 cuts each end), so the holding/indexing techniques may need to be a little different. Nice approach for cutting other types of collet though. Regards, Tony ------- Date: Thu, 29 Mar 2001 00:35:07 EST From: ajkdfwx~xxaol.com Subject: Re: Collets There certainly has been a lot of useful information on collets and the potential use for them in the past 8 hours. I'm still very much in the dark as to how to utilize the slitting saw to machine custom size collets however. Does anyone have a method for holding the little devils while you slit them? I realize I could take the long way round and chuck one in a vise and then use a jewelers saw, but then, what good is the slitting saw? As far as the spindle size not allowing 3/8" endmills, I chickened out on drilling and reaming mine the extra 1/32 to facilitate this. I went ahead and machined a blank arbor with a setscrew instead and use this when I need to use endmills with 3/8" shanks. AJ ------- Date: Thu, 29 Mar 2001 10:47:41 -0000 From: J.C.Beechx~xxshu.ac.uk Subject: Re: Collets Not quite as straight forward as the rest, but, Machine a block to take the collet. Now slit the block along its centre and skim both faces (for clearance of the slitting blade). Take your reamed collet and fit a brass rod the bore of the new collet and clamp in the block. Now slit the collet at one end, when this is complete turn the block round, replace the brass insert and slit from the other end. (forgot to say rotate the collet in the block by 90 deg for the two slits. There is a nice and easy way to accuratly slit the collet and the block is available for use later on. Joules ------- Date: Mon, 16 Apr 2001 23:59:00 -0400 From: Stan Stocker Subject: Re: Dumb Question Don Feinberg wrote: > I have a dumb question -- not necessarily related to Taig, but > someone here will probably know the answer... > I have a drill press on which the chuck is held by an MT2-taper shaft. I > need to change that chuck. However, that MT2 shaft is definitely > "in there" :-) :-) I have no simple ideas for how to separate that > MT2 pair (it sure went in there easily enough!). > Can anyone suggest a rational (non-destructive) way of getting that MT2 > shaft -- and, therefore, the chuck -- out? Thanks. Don Feinberg Lower the quill and see if there are a pair of slots opposite of each other through which you can see the spindle. If so, rotate the spindle by hand until you see a slot through the spindle and the end of the MT2 adapter. A tool known as a drill drift or knock out wedge (likely by a million other names as well) is used to knock out the chuck on the arbor. A drift for MT2 is a piece of steel about 4 inches long, one inch wide, and 1/4 inch thick, with a 15 degree taper on one end, reducing the one inch width to about a quarter inch. The end that goes into the spindle should be slightly rounded so you don't raise a burr that falls down into the works later. You put the drift into the slot of the spindle flat side up, with the taper pressing down against the tang of the adapter and give somewhere from a love tap to a heavy blow to the one inch wide end of the drift. Out comes the adapter. If you want to buy a drill drift, Enco has them. An MT2 drift is $1.79, stock number 292-6225, on page 156 of the 2001 catalog. The vast majority of tool vendors have these, they are not a rare item, as they are a shop expendable item in shops that use MT drill bits. If you have a piece of steel anywhere from 1/8 to 1/4 thick, just hacksaw the taper, smooth with a file, and be done with it. I've made them when needed somewhere away from my toolbox, it's maybe a five minute job. Beats waiting on delivery if you don't have an order going anyway. To remove a chuck from an adapter can become a whole other exercise. There are wedges sold that look like pickle forks used in suspension work, just smaller. If the arbor has a surface to bear against by the chuck, you can sometimes pull a chuck from an arbor using these. Note that most portable drills use a threaded mounting similar to the Taig tailstock while most drill presses and R8 to chuck adapters use a Jacobs taper to secure the chuck. If you are buying a new adapter or a new chuck, you need to match the Jacobs taper of the chuck and the taper of the spindle. You'll see that chuck adapters specify something similar to MT2-6JT or R8/JT33, indicating a morse taper 2 to Jacobs taper 6 and R8 to Jacobs taper 33 respectively. JT6 and 6JT are the same thing, I've seen both used in catalogs. When you go to reassemble, the tapers should be clean, free of any debris or burrs, and DRY! No oil, no Loctite, just clean and dry. Open the chuck until the jaws are retracted into the body, put the chuck on the adapter if it is off, put the adapter into the spindle. The taper should grab and hold lightly on hand insertion with a nice little plonk sound, just like a lathe center. Use the quill to press the chuck firmly down onto a piece of wood on the drill press table. Pressing against the wood seats the adapter just fine. If it doesn't, you have a damaged/dirty/oily socket or taper surface. As the existing adapter is firmly in place, the socket is likely in good shape. Retracting the chuck jaws prevents damage to the chuck. Stan ------- Date: Thu, 19 Apr 2001 03:50:12 -0000 From: cmsteamx~xxatlnet.com Subject: Sherline mill collet drawbolt tip: Hi Gang, I do engraving frequently and the need to use available 1/8" dia x 5" long cutters poses a problem holding them with a collet because the drawbolt is solid. Solution is to drill the bolt number 11 drill (just over 3/16" dia). Fills the bill nicely. This is useful for holding long drill bits also. Rich D. ------- Date: Sun, 27 May 2001 18:02:24 +0000 From: Jon Elson Subject: Re: collets for 10" jet wrote: > I'm a bit fuzzy on collet sizing, so this may be a pretty basic question. > If I were looking to buy a drawbar and collet set, what sizes should > I be looking at for a 10"? 3AT? 3C? Something else? If you know > of a web site that explains collet sizing, please drop me email. The 10 and 12" Atlas lathes have a #3 Morse taper on the headstock. So, you could use MT 3 collets directly in the spindle, with a drawbar collet closer. One problem is the Morse taper collets have a small internal thread, so long stock can't pass through the collet and hang out the back. The 3AT and C type collets are designed to use an external thread to close the collet, so a draw-tube can pull the collet in, allowing stock to pass through both. 5C collet chucks generally have the closer thread built into the chuck, and the chuck screws onto the spindle. The 5C collets go up to about 1", 3C and 3AT collets are much smaller, limiting workpiece diameter. One other possiblity is to modify #3 MT collets with an external thread, and bore out the center enough to clear a workpiece the same size as the collet. Then, you could make a draw-tube to fit. Jon ------- Date: Thu, 31 May 2001 07:49:06 -0500 (CDT) From: dswrx~xxwebtv.net Subject: Re: Re: Collets issue My suggestion is NOT to tap on the drawbar at all. Remove it first, then using a brass rod that is a little smaller in diameter than the diameter of the bore and longer than the length of the bore, propel the rod into the bore and it will dislodge the collet. Make sure to catch the collet holder as it is dislodged. Leo ------- From: Stan Stocker Date: Fri Jul 20, 2001 10:44 pm Subject: Re: [taigtools] Using the grinding wheel set? Leon Heller wrote: > I've got the grinding wheel set. How do I go about grinding my own lathe > tools? I suppose I can do it freehand, but I really need some sort > of fixed support for the tool, that can be set to the various angles > needed. I suppose I could make my own that attaches to the cross-slide. > How about using clingfilm to protect the bed and carriage? > Leon Heller, G1HSM Tel: +44 1327 359058 > My web page: http://www.geocities.com/leon_heller Leon; Probably one of the best sets of instructions around for basic lathe tool grinding can be found on the Sherline site at: http://www.sherline.com/grinding.htm You will need to cobble up some sort of a tool rest, but a block cut on a 7 degree angle with the sawn side smoothed with a file or on a belt sander might be sufficient depending on just what forms you need on your tools. If you have a mill it gets a lot easier, but it is amazing what you can do with a hacksaw, files, and abrasive if a mill isn't handy. Once you read the Sherline info you'll likely get some pretty good ideas about quick and dirty fixtures that will work with whatever is available. Stan -------- From: James Eckman Date: Sat Jul 21, 2001 11:38 am Subject: Re: Using the grinding wheel set? From: "Dave Norling" > Are you really going to chuck up a grinding wheel in your lathe and > let all that abrasive grit fall onto your precision lathe bed? Sure why not? If the only machine tool you have is the lathe, you have to use it. This seemed to be typical for the old watchmakers since there were grinding attachments for the old lathes and most watch books showed grinding on the lathe. Jim Eckman ------- From: "Nicholas Carter and Felice Luftschein" Date: Sun Jul 22, 2001 1:50 pm Subject: Re: [taigtools] Using the grinding wheel set? I generally recommend getting a banch grinder, as the grinding wheel set is really best for just touching up already formed bits. Plastic wrap will help protecting the bed, but be aware that grinding on the lathe will always result in a little grit getting past your defenses. I grind everything freehand, and have become pretty skilled at putting the proper angles on, checking against a protractor, etc. See our web pages http://www.cartertools.com/nfhome.html ------- From: Myron Gochnauer Date: Sun Aug 5, 2001 10:06 am Subject: toolbit steel Does anyone know what the official Taig toolbits are made of? Are they a standard M-2 HSS? I've been looking around for HSS toolbit blanks. Enco seems to have good prices (although they apparently won't send to Canada) for 1/4" M-2, 5%, 8% and 10% cobalt bits. ...no mention of where they are made. I'd trust US, Spanish or perhaps Japanese made steel the best. Comments? Suggestions? ...not point in using questionable material, especially when I'm learning the skills. Myron ------- From: "Nicholas Carter and Felice Luftschein" Date: Sun Aug 5, 2001 12:59 pm Subject: Re: [taigtools] toolbit steel They buy raw HSS stock from England, mill, heat treat and grind. I think that 5-10% Co toolbits are a good deal, even as imports from ENCO. For real heavy duty, try some stellite/tantung bits, hard at red heat! See our web pages http://www.cartertools.com/nfhome.html ------- From: bweishapx~xxg... Date: Thu Aug 9, 2001 7:52 pm Subject: ww headstock, spindle, pulley and drawbar Was wondering if anyone had any idea if the above would fit my WW 8mm collets? I have a Boley Jewelers lathe with 8mm collets. If they would fit the above I would opt to buy the set which is a W1020 so I could use them on my Taig. I really like it but making small clock and watch parts it would be nice if it did and make it more versitle to me. Thanks. Bernie ------- From: "David Robertson" Date: Thu Aug 9, 2001 10:37 pm Subject: Re: [taigtools] ww headstock, spindle, pulley and drawbar Bernie. They are supposed to... Nick Carter can probably tell you for sure. If you haven't yet bought the lathe, this may be the way to go. I already had a Taig and wanted to use my WW collets, so I made a chuck to hold the collets from one of the Taig blank arbors. I just drilled a hole in it the size of the straight part of the collet and than cut a 20 degree taper on the entrance to the hole for the tapered part of the collet to fit into... (trial and error to get it the right depth.. since there is variability in WW collets. Then I ordered a draw bar from Pat Cavenaugh clockdokx~xxo... .. the correct length (it is adjustable however) and turned a bushing so that the back end of the drawbar would fit snugly and concentrically in the pulley end of the headstocks spindle. Voila... a WW chuck for the Taig for less than $20 and an hours work. Dave ------- From: "Carol & Jerry Jankura" Date: Thu Aug 9, 2001 11:11 pm Subject: RE: [taigtools] ww headstock, spindle, pulley and drawbar David: Is the drawbar that you ordered anything more than a Hex bolt with the proper thread to fit the WW chuck on one end? Is this someting that you could of turned with your Taig? Your message gives me some ideas of what to make for my Sherline lathe, and how to do it. It sure sounds like a good use for Taig's arbor, which just happens to fit the Sherline as well. Jerry Jankura Strongsville, Ohio -------- From: Tony Jeffree Date: Fri Aug 10, 2001 1:38 am Subject: Re: [taigtools] ww headstock, spindle, pulley and drawbar >Voila... a WW chuck for the Taig for less than $20 and an hours work. Dave - I worry about the accuracy of doing it this way - just after you've turned the taper, it will of course hold the collets exactly on centre, but after you've removed the adapter from the spindle nose & re-fitted it, what kind of runout do you get on the collets? I suspect it will be significant - or at least, very dependent on how well that particular blank arbor fitted the spindle nose. A question, that you may be able to answer...isn't there a difference between WW (US) and 8mm (European) collets? We had a conversation about this on the list a while back - Sherline sell 2 different collet adapters for their rotary table, one for WW and one for 8mm. My best guess was that WW are essentially Imperial, and have a nominal shank diam of 5/16" (7.9375 mm) rather than a true 8mm, and that European 8mm collets use a metric pitch thread for the drawbar (where WW uses .275" X 40TPI). Is this correct? .275" is remarkably close to 7mm (6.985), and 40 TPI is 0.635mm pitch, so is the true 8mm collet threaded 7mm X 0.6mm pitch? Regards, Tony ------- From: "David Robertson" Date: Fri Aug 10, 2001 12:22 am Subject: Re: [taigtools] ww headstock, spindle, pulley and drawbar Jerry, The WW collets have external threads so the drawbar has to be a hollow tube with internal threads to fit the collet. The collet threads are approx .275" x 40tpi so not easy to do on Taig without proper size tube and proper tap. Drawbar costs $15. Woops.. picture got stripped... if interested you can see it at http://www.open.org/~clockdok/collet.html Dave Dave ------- From: "Nicholas Carter and Felice Luftschein" Date: Fri Aug 10, 2001 1:33 pm Subject: Re: [taigtools] ww headstock, spindle, pulley and drawbar There are several things you need to look out for: Not all WW collets are the same. Those with .313+ body diameter wouldn't fit, and some have longer bodies (Starret collets) need a spacer between the spindle and drawbar to take up the slack. The idea of making an adapter from the 1132 blank arbor is pretty good and if you take pains to clean the threads each time it should be pretty repeatable. See our web pages http://www.cartertools.com/nfhome.html ------- From: joel_mowersx~xxp... Date: Fri Aug 10, 2001 5:46 pm Subject: Re: ww headstock, spindle, pulley and drawbar Have been using the WW Taig headstock for several months now with no problem. As far as I know, WW and 8mm are the same thing. I have a motley collection of old collets that work fine. I also have several Sherline Imperial size collets that work fine. Also, you can get 8mm to 3/8" and 3/4" adapters from Sherline that will adapt Jacobs chucks etc. to the spindle. Ofcourse, the outer thread on the Taig WW headstock spindle is 3/4"-16 so you can use all of the Taig chucks, faceplates etc. I don't think you'll have any problems going WW. Joel ------- From: "David Robertson" Date: Fri Aug 10, 2001 6:28 pm Subject: Re: [taigtools] ww headstock, spindle, pulley and drawbar Tony... Good questions... I'll answer as best as I can. > I worry about the accuracy of doing it this way - just after you've turned > the taper, it will of course hold the collets exactly on centre, but after > you've removed the adapter from the spindle nose & re-fitted it, what kind > of runout do you get on the collets? I suspect it will be significant - or > at least, very dependent on how well that particular blank arbor fitted > the spindle nose. I haven't checked.. but also haven't used this setup but once since I have a couple of watchmakers lathes that I usually use when I am using WW collets. I will try removing and reinstalling a few times and see... I'll report results. I mianly did it so that I could use the WW collets in the Taig but have not had occaision to do so. > > A question, that you may be able to answer...isn't there a difference > between WW (US) and 8mm (European) collets? We had a conversation about > this on the list a while back - Sherline sell 2 different collet adapters > for their rotary table, one for WW and one for 8mm. My best guess was that > WW are essentially Imperial, and have a nominal shank diam of 5/16" (7.9375 > mm) rather than a true 8mm, and that European 8mm collets use a metric > pitch thread for the drawbar (where WW uses .275" X 40TPI). Is this > correct? .275" is remarkably close to 7mm (6.985), and 40 TPI is 0.635mm > pitch, so is the true 8mm collet threaded 7mm X 0.6mm pitch? I don't really know the answer to all of this. What I can tell you is that there are several diffferent colelts that are called "WW". Most are very similar and are the ones made by Levin, Peerless, Starrett, Webster Whitcomb and some others. I can't tell you that these are exactly alike... only that they are close enough to seat properly in my Levin watchmakers lathe. There is a Mosely which is longer and Mosely Conoidial which is same length (approx) as the long Mosely's but also have a gentle curve from the straight shank to the flared portion of the collet... rather than the sharp angle that is on all the others. These will work (i.e.seat) in my Levin but need a spacer about 1/16" thick between the knob on the drawbar and the back of the lathe spindle. I know that there are several similar but actually different thread pitches and thread diameters.. your explanation may be right and explain the differences. You've exhausted over 100% of my knowledge on the subject. I'll let you know how the runout test goes. Dave ------- From: "David Robertson" Date: Sat Aug 11, 2001 1:26 pm Subject: Re: [taigtools] ww headstock, spindle, pulley and drawbar Tony, you were right. the runout on the inside taper is .002 - .004" Runout is fairly consistent through several removals and reinstallations. Makes me think I didn't have the blank arbor and spindle threads squeaky clean when I was making it since error seems repeatable now. I will probably try making another and see if I can do better... Thanks for the question... I hope to end up with a better device in the long run. Dave ------- From: "Jack Gartner" Date: Thu Jul 6, 2000 12:34 pm Subject: Re: WW collets, etc. > ... There is a bit of confusion regarding Sherline collets. They > make a 5/16" collet adapter and an 8 mm collet adapter. The best > approach to the use of collets in the Sherline lathe is to purchase > their 8-mm WW collet adapter and draw bar.... I'm kind of new to this and therefore not that familiar with the terminology. Was reading old notes to learn about collets and came across your note. Maybe you can help… I'm confused about the meaning of the "WW". After reading your reply and the Sherline documentation for their collet set (http://www.sherline.com/1160inst.htm) I get the impression that WW collets come in both metric and english versions; and that the metric version is 8mm and the english version is 5/16. Is this correct? What exactly does the "WW" signify, (vs. a 5C collet for example)? The angle of the taper, the length? What does the 5/16 (or 8mm) signify (The outer diameter of the collet?) Do WW collets come in other sizes besides 5/16 and 8mm? ------- From: Ron Ginger Date: Thu Jul 6, 2000 2:20 pm Subject: Re: [sherline] Re: WW collets, etc. Jack Gartner wrote: > I'm kind of new to this and not that familiar with the terminology. There are two parameters of interest in collets, one is the type or style of collet, the other is the size of material its made to hold. There may be a million types of collets- manufacturers used to make their own style to force you to buy from them. In more recent years some standardization has arrived, but there are still a lot of them. WW and 8mm refer to type of collets, as does 5C, 4C, 3AT, R8 etc etc. There is NO detectable logic to the names of collets- they are just plain old marketing terminology. For Sherline machines WW and 8mm are suitable types. The next value of interest is the hole, or the size of materail the collet will hold. These are available in both inch and metric values, so you can buy a ww colet to hold 1mm stock, or an 8mm collet to hold a .062 rod. It is also true that collets labeled WW or 8mm may not always be interchangeable. Some manufacturers would call their collets WW, but make just enough change in drawbar thread or OD or angle to make them incompatable. Note also that collets must fit the work very closely. You cannot expect good holding or accuracy if you try to use a 1/16" collet (.062) to hold a wire that is .050 for example. If you get into collets you wind up with LOTS of them ron ------- From: David Eiman Date: Fri Jul 7, 2000 12:24 pm Subject: Re: [sherline] WW collets The WW stands for Webster-Whitcomb. Ambrose Webster and John E. Whitcomb were two Americans. The designed and made lathes in the second half of the 19th century. They came up with the standard dimensions that are used today. The Europeans pretty much copied the American design here. The history is written in The Watchmakers Lathe by Goodrich. I have an extra copy available (new). I stock the metric collets in tenth of a millimeter increments made by Starrett at $11 each. I stock sizes from 5 to 80. I have been selling these for over 13 years and the inventory is a nightmare at times. I am also a Sherline dealer, but their offering of metric collets is only in half millimeter increments. For clock work these gaps are too great. A full set of collets makes a lathe more useful. I got into this when I was trying to complete my own working set of collets. I just use the required size and don't worry about brand names in my working set (although somewhere I have boxes to collect sets by maker for various lathes I don't use). David David Eiman * Around The Clock Fresno, CA * NAWCC 0072811 Collect-buy-sell-trade antique & modern watchmakers lathes ------- From: WRSmith2x~xxa... Date: Fri Jul 7, 2000 1:48 pm Subject: Re: [sherline] WW collets WW stands for Webster Whitcomb. This is the "pattern" of watchmaker's lathe that became the most popular of all such lathes. When purchasing a watchmaker's lathe, it is always wise to buy a WW pattern lathe because more attachments are available for it on the used market than any other pattern. The WW pattern lathe was made by Derbyshire, Levin, Boley and a number of other makers. TTYL W. R. (Bill) Smith 8049 Camberley Drive Powell, TN 37849-4218 Phone: 865-947-9671 ------- From: waldronx~xxw... Date: Fri Aug 17, 2001 12:44 pm Subject: WW collet runnout I have been comparing the total indicated runout on some of my WW collets, and wonder what is considered acceptable. The five collet set I bought from Sherline measures .0005" TID, with the 5/16 measuring higher. The 5/16 collet could be a measurement problem on my part, as the test pin only goes in about a quarter inch. However, I also have several Starrett WW collets, brand new,some of which measure as much as .0025 TID. I think that is a bit much. I used ground dowel pins to check, and the 1/8 inch dowel that gave .0025 with the Starrett gives .0005 with the Sherline collet. Any thoughts? Thanks, Brian ------- From: n2562001x~xxy... Date: Sat Aug 18, 2001 12:01 am Subject: Re: WW collet runnout Brian, I have both Sherline and Starrett collets as well as hardened collets. I have had little problem with any of them when properly used. A 0.0025" runout for any collet would not be exceptable to me. I will make the assumption that you are using the 8mm collet holder with the 8mm starrett collets. I will also make the assumption that your starrett collets are numbered collets and that the stock you are using to test the runout is round and proper diameter to fit the collet. If the assumptions are correct then I would contact the dealer or Factory for a solution. Jerry Kieffer ------- Date: Fri, 31 Aug 2001 23:00:22 -0400 From: Stan Stocker Subject: Re: Re: Grinding your own bits Gord and Doreen Smith wrote: > Up 'til now I have been using proprietary bits but I should get into > grinding my own . I have a double ended grinder (6") so what grade of > wheels would give me the best ability to grind my own bits? Gordo Canada A 46 for roughing and a 60 for fine work is a pretty good combo. The white aluminum oxide wheels from Norton are quite good, far better than no name gray wheels. J hardness wheels grind cooler, but require more frequent dressing than harder weels. As a default setup, a 46J and a 60J is a good combination. Harder wheel glaze easier than softer ones. As with most things, there is a trade off. You might enjoy a look at the Norton web site, the link to their lit page is: http://www.nortonabrasives.com/industrial/asp/product_lit_list.asp Stan ------- Date: Mon, 03 Sep 2001 04:57:25 -0000 From: jtoolman2000x~xxhotmail.com Subject: Re: Can anyone recommend a good source for tool bits? First, I would stay completely away from using cheap brazed carbide such as those found in some mail order catalogs for a buck a piece. Completely useless. The Taig is very lightweight and not really intended to cut with carbide. You can get good HSS bits in 1/4" from many companies like ENCO, Grizzly, MSC, J&L etc. You will pay about $1 as piece and up depending on quality. If you don't know how to grind, I would make it a priority item. It makes a world of difference how the tool is ground when it comes to a great cut versus a terrible one. I have a page on my web site that gives examples of various tool grinds as well as a couple of diagrams. Any good book on machining will cover that as well. If you need them pre ground, Taig sells them of course. I don't now where you are as far as machining so I don't exactly what to tell you. Basically, stay away from the cheap carbide. Some are fairly good ( $6-7 a piece USA made) but although I have quite a few, I find that I do not ever need them for just about anything I attempt to machine. HSS can be brought to a much keener and longer lasting edge than brittle carbide. Take care jose http://www.homestead.com/tool20895/jose7x10taig.html ------- Date: Mon, 03 Sep 2001 05:03:55 -0000 From: jtoolman2000x~xxhotmail.com Subject: Re: Grinding your own bits YES! Do learn to grind your own tools. It will same many $$$ over buying pre ground HSS. HSS tooling can be brought to a great edge that carbide cannot achieve. Blanks are cheap! I use a 60 grit and a 100 grit white whell for finish grinds and touch ups. I have a grinding page on my site at: http://www.homestead.com/tool20895/jose7x10taig.html There is a picture / link on the main page. Jose ------- Date: Mon, 03 Sep 2001 15:59:25 +0100 From: Tony Jeffree Subject: RE: Re: Can anyone recommend a good source for tool bits? At 09:35 03/09/2001 -0400, you wrote: >Other than country of origin, what are the differences between the "cheap >carbide" tools and US made carbide tools? Primarily those with 1/4 x 1/4 >inch shanks. There are cheap imported tools available that originate in the far East and/or India (the latter in the case of the ones I have seen here in the UK). The differences are as follows (at least in the ones I have, and that I don't bother to use anymore!): 1) The standard of machining of the shanks is bad - the replaceable inserts are not held accurately, resulting in no guarantee that you can replace a broken tip without having to re-set the tool position during a cut. Well-made tools (US, UK & European in origin) are machined more accurately, so that the insert is held in a repeatable position. We have a supplier here in the UK that makes a very nice double sided holder - can be converted between left & right-handed knife tool by moving the insert from one side to the other. Very handy, accurately made, and competitive in price too. 2) The socket head screws supplied were of very poor quality - a couple of the tools in my set of 5 are so bad that it is not possible to remove the "replaceable" insert. 3) The inserts themselves were not terribly good - more fragile than the better quality ones, and with tip radii way too large for the size of machine that they are aimed at. I use Sandvik inserts, generally with a tip radius of 0.2 or 0.3mm for general purpose work, and 0.1mm if I want a really fine finish (these give a mirror finish on aluminium, for example), and they are not much more expensive than the cheap imports. Regards, Tony ------- Date: Mon, 03 Sep 2001 16:03:08 -0000 From: n2562001x~xxyahoo.com Subject: Re: Can anyone recommend a good source for tool bits? Jose wrote > First, I would stay completely away from using cheap brazed carbide > such as those found in some mail order catalogs for a buck a piece. > Completely useless. The Taig is very lightweight and not really > intended to cut with carbide. Jose: You are right about the cheap carbide, however I disagree with you on the use of brazed carbide with small lathes. I have used 1/4" Caboloy (US made at about $4.00) brazed tools in Taig sized lathes for many years. The work size has ranged from what ever the lathe could handle down to watch parts and smaller. They eliminate the need for time consuming grinding and last far longer the HSS . Once the tool post is set there is no need to constantly adjust height of the tool. They have worked well on all types of material as long as you have the ability to ajust speed while cutting to get the proper finish. Jerry Kieffer ------- Date: Tue, 09 Oct 2001 04:53:41 +0000 From: Jon Elson Subject: Re: HSS vs Indexable Carbides got_milk_ehx~xxyahoo.com wrote: > Just following the recent discussion on toolposts and I had a > followup question for the list. I'm looking to outfit my atlas 10" > with a quickchange toolpost and I'm looking at also buying an > indexable carbide bit set to go along with it (combo sale). So my > question is, in the long run which will be cheaper/easier? Going > with HSS and regrinding as needed, or using indexable carbides. I > mainly work in aluminum and was thinking that perhaps the indexables > might be cheaper. Should require less sharpening and last longer, > hence I could get away with using a couple for a very long time and > no need to grind them or replace them as often as HSS. How well does > this work out in practice? Thanks for your help, I got a 5-piece, 3/8" indexable set years ago, and have been very happy with it. I occasionally use HSS tools, or brazed Carbide threading tools, but use the indexable tools much more than anything else. I don't sharpen my indexable tools. As a matter of fact, the indexable insert only overhangs the holder by about .020". So, you can't grind much off at all. Also, the carbide RARELY wears down, unless you are turning something REALLY hard. It usually crumbles a little at a time, eventually becoming too rough to use for any purpose. You can't grind carbide on an alumina wheel, anyway. It will just wear down the wheel without doing more than buffing the carbide. As for how long the carbide lasts, it can last 100 times longer than plain HSS! Maybe 10 times longer than high-quality name brand HSS lathe tools that have been ground very carefully to not change the temper, and are run at the perfect speed, with lots of coolant. With carbide, you can still cut steel when the cutting edge is red hot! Get an HSS tool much hotter than boiling water, and the temper is gone, and the tool will wear out in seconds. Jon ------- Date: Sat, 17 Nov 2001 10:36:17 -0800 From: Dave Martindale Subject: maintaining concentricity A while ago, I machined a new collet for a (woodworking) router. It took me several tries to get something that worked tolerably well. The problem is that the hole in the middle (that holds the router bit) needs to be near-perfectly concentric with the outside tapered surface (which fits into a taper on the router armature). I tried drilling and reaming (for surface finish), but it just wasn't good enough. The drill cuts a hole that isn't really straight or centered and the reamer follows it, giving something that's not concentric. And if the reamer is held in the tailstock, and the tailstock is not perfectly aligned with the headstock's rotation axis, the walls of the hole are probably not exactly parallel either. I eventually figured out that I had to add a boring step. Boring the hole with a single-point tool makes the hole concentric with the headstock rotation axis, and thus concentric with the outer surfaces which are also single-point turned. So the steps were something like: 1. center drill 2. drill to full depth with pilot drill (1/16"?) 3. drill to full depth with 3/16 drill 4. bore out to 0.240 (approx) with boring tool 5. ream with 0.250 reamer loosely guided by tailstock chuck 6. turn outer surfaces to needed tapers 7. part off These steps were all done without ever removing the part from the chuck. I think you'd also have to use a boring step when making something like an endmill arbor. Dave ------- Date: Sat, 17 Nov 2001 11:15:02 -0800 From: "Craig Libuse" Subject: Re: Re: looking for end mill holders and slotting saw arbor > However, when you mention that 'perfect concentricity is always > difficult to maintain on a threaded part, I begin to > think using the mill collet might be the answer. Mr. Dubin, A1/4" mill collet or WW collet will likely have less runout than an end mill holder. There are just less things to go wrong in production and less ways for chips or dings to adversely affect the installation. Just make sure your internal spindle taper is in good shape and clean. Collets are also a relatively cheap solution and one that is quick and easy to install each time. Craig Libuse Sherline Products ------- Date: Sat, 17 Nov 2001 19:48:13 -0800 From: "Marcus & Eva" Subject: Re: Re: looking for end mill holders and slotting saw arbor Hi Wm: If you are after very accurate concentricity, your best bet is to use a single piece, inserted into the morse taper in the spindle. Here's what I would do: Buy a spare #1 morse taper center from Sherline. Wipe the inside of the spindle and the body of the center perfectly clean. Grind a tiny dimple on the front of the spindle nose and onto the center as a reference mark so you always place the cente in the same radial orientation. Turn down the front part of the center to 0.200" dia exactly. If you want to get really fussy, turn it 0.001" oversize and lap to final diameter. If you were careful with every step, you will have a pin that is as concentric as you will ever get. Cheers Marcus ------- Date: Fri, 28 Dec 2001 03:03:45 -0500 From: Stan Stocker Subject: Re: Honing Toolbit If you stroke perpendicularly to the cutting edge, the edge will be stronger. Stoning and honing leave scratches in the direction of the stroke. If these scratches are parallel to the cutting edge, the edge is weaker. This is something worked out by woodworkers over the years, particularly with water stones and laminated cutting tools as used in traditional Japanese woodworking and carpentry, where the edge is very hard and prone to chipping if not sharpened with great care. If you do the final honing from the cutting edge back onto the tool, so the cutting edge leads each stroke, there will be less of a burr at the edge. This gives a stronger edge also. Best wishes, Stan ------- Date: Sat, 29 Dec 2001 01:31:14 -0700 From: "Steve" Subject: Re: Re: Honing Toolbit Hi Yuji, For more information on sharpening tools take a look at the Sherline web page here: http://www.sherline.com/grinding.htm Great info - happy sharpening, Steve ------- Date: Tue, 1 Jan 2002 09:48:44 +1100 From: "Peter Homann" Subject: Modifying /Making Collets? I have a number of milling bits that have metric shanks, 6mm to be exact. My questions are: 1. Is it possible to drill and ream out a smaller Collet to 6mm? If so any advice would be appreciated. 2. If I have to make a 6mm Collet from a blank one, how does one hold a blank Collet to put the slits in it? Sorry for the terse questions, but I have to take the young one to the cinema to see Monsters Inc. Cheers, Peter Homann Work : +61 3 8530-7755 Adacel Technologies Ltd Fax : +61 3 9596-2960 250 Bay St, Brighton 3186, VIC, AUSTRALIA Mobile : 0421 601665 http://www.adacel.com.au Australian Software Engineering Excellence ------- Date: Mon, 31 Dec 2001 22:55:39 -0000 From: "jlm_1951" Subject: Re: Modifying /Making Collets? I side stepped the slitting problem by drilling and tapping a 6-32 set screw from the side (I needed a holder for the small diameter Dremel tool bits). So, in a sense I made a tool holder instead of a collet, but it works fine for the specific size I drilled. Joel ------- Date: Mon, 31 Dec 2001 23:09:29 -0000 From: "wishbone_aaa" Subject: Re: Modifying /Making Collets? > If I have to make a 6mm Collet from a blank one, how does one > hold a blank Collet to put the slits in it? I force fit the collet on a wood shaft with a slight taper and hand cut the slots with a jewler's saw. Don ------- Date: Mon, 31 Dec 2001 18:35:10 -0700 From: "Steve" Subject: Re: Modifying /Making Collets? Hollow out two pieces of wood to fit the collet, clamp the wood & collet in a vise, and free hand cut with a jeweler's saw or a slitting saw on the Taig. I'm too lazy to hollow the wood out tho, so I just clamp a collet between two 1X2's in the vise and use the jeweler's saw. I started using the slitting saw, but it takes a really long time to set it up safely. Then I found I could hold the collet between my fingers and cut a slot with a jeweler's saw in about 30 seconds. Then I nicked my thumb & decided to clamp them between the wood instead! I have also cut the slots with a dremel cutting disk, but the dust is really messy and it isn't a whole lot faster. It is also very easy to make "Tween" size collet bushings for that odd drill bit or rod size from brass rod. I usually make them from 1/4" rod drilled to the desired size and then slit them right in the collet. See the example in my directory on the yahooz group: http://groups.yahoo.com/group/taigtools/files/Simons_Taig_Pics/ColletBushing End.jpg http://groups.yahoo.com/group/taigtools/files/Simons_Taig_Pics/ColletBushing Side.jpg These were both cut freehand with the jeweler's saw and show that the slots don't have to be straight to work (but they would look nicer!). Steve ------- Date: Thu, 10 Jan 2002 21:01:23 -0500 From: ron ginger Subject: Re: Form tools As someone noted, you can buy square tool blanks to grind to shape. But these are hard- must be ground and being 1/4" thick grinding any complicated profile is going to be hard and slow. I took a simple piece of 1/4" square steel key stock and made it into an inserted tool holder. Look at the commercial holders for carbide inserts to see how they look. I make the form inserts out of 1/8 or even 1/16 thick ground flat stock. You can order this from any of the supply companies- MSC, J&L, etc. It can be cut with a hacksaw, and filed to shape. Then harden it simply by heating red hot with a propane torch and quenching in water. You can draw back the temper a bit, but for making just a few parts for a model its not necessary. In fact, I have used it without even hardening it to cut brass, aluminum or plastic. Note if your shape requires accurate round section you should drill and ream a hole of the right diameter before you cut the profile. Much easier to have a drilled hole than to hand file a half round shape. Ive made these as much as 1/2 to 3/4 inch wide to cut things like model ship railings. As they get too wide you must cut slow to prevent chatter, but they can work. ron ginger ------- Date: Fri, 11 Jan 2002 06:49:34 -0800 From: mark Subject: Sharpening lathe tools A friend showed me a little setup using a diamond lap (!) for sharpening his watchmakers' gravers (carbide)..... These seem to be most often used for lapidary work like gem faceting / rock polishing. There are various brands available, the best value when I went looking seems to be from Daniel Lopacki. 600 to 1200 grit will put a great finish on your chisels and carving knives, too. (in the 30.00 range, I seem to recall - I chuck mine up using a quick and dirty mandrel, in my "other" lathe.) Squirt a little windex on it now and again (the lap). mark ------- Date: Fri, 11 Jan 2002 15:47:53 -0600 From: "Joe T. Travis" Subject: Re: Sharpening tools with a belt/disc sander? Bryan, I started out sharpening my bits on a grinder per the Sherline instructions. Last summer I purchased the Machineshop Lathe Course video series from Am. Gunsmithing Institute (10 tape series that I highly recommend, I am now in the market for a full size lathe, though!). About half of one tape is devoted to tool sharpening - they use a belt sander exclusively. I started using one and have been much happier with the results. My cuts are much, much smoother now. I have the Delta grinder you do. Metal cutting belts in various grits are available from several sources (Brownell's, Klingspor). One thing they did in the video was to make a bunch of 1" square "bits" out of wood for practice. They cut a lot faster and it is easier to measure the angles and get the feel of creating the proper reliefs. I now have a set of wood "masters" with the correct angles for reference and practice on wood occasionally. The backing platen on the Delta is a bit flimsy - you need to get it as parallel and close to the belt as possible - some of the graphite tape on the platen might help - been meaning to pick some up. I keep the table on the 1" belt set at 7 degrees and a fine belt on, just for quicky sharpening - it's so much quicker and easier than a grinder. FWIW, they teach "grinding" the edges in a different order than Mr. Martin does - don't know that the order matters. I do use his method of cutting the rake on the top surface that he describes. http://www.americangunsmith.com/machine_shop_lathe.html#anchor02 http://www.brownells.com ------- From: "coyneg" Date: Thu Jan 17, 2002 3:59 pm Subject: Re: O-ring groove lathe bit What you want is known as a "grooving tool". These can be used like a lathe cutting tool in either axis, for cutting an o-ring groove on a shaft, or for cutting an o-ring groove into a bore hole. They're generally solid carbide tools, look kind of like a boring bar... I don't know about metric sizes, but MSC has them in fractional/ decimal inch sizes. Take a look at MSC, www.mscdirect.com, search for "o-ring" or "grooving tool"... ------- Date: Sat, 16 Feb 2002 23:08:34 -0500 From: Stan Stocker Subject: Re: Which cutter? Most used lathe tool is a right hand, 7 degrees front and side clearance, 1/32 inch tip radius. 0 top rake for brass, 7 degrees for steel, around 12 to 15 degrees for aluminum. Stan ------- Date: Sun, 17 Feb 2002 15:11:22 -0500 From: Stan Stocker Subject: Re: Which cutter? Hi Bill: Don't sweat getting the angles dead on! I have my grinder table set to about 7 degrees, and free hand the top rake. As long as you have some front and side clearance you are fine. If you end up with 5 degrees it isn't a big deal, it still clears the work. Just don't end up with 30 or 40 degrees of clearance, you want the cutting edge supported so it doesn't wear quickly or chip. Better to spend the extra 5 minutes stoning the edges to a good finish than to spend it chasing fractions of an angle. The only time this isn't true is when grinding tools for single pointing screw threads, but as we don't have this capability on the Taig, unless you do a home brew or Frog add on, this doesn't apply. You might want to wander over to Sherlines site and read their information on grinding tools. They have a good write up, with a very practical approach to it all, rather than burying you in tiny detail more appropriate to a person making production tooling or with access to a tool and cutter grinding setup. Here's the URL: http://www.sherline.com/grinding.htm Once you have read that site, there's a file in the files section, stantoolgrinding.doc or .txt, it's been a while. While some of the info relates to larger tooling, there is some useful info for all size lathe tooling. Originally an email on the model engineering list, I was responding to questions about tool tip radius and its effect. Have fun, play around, it all falls into place with a little practice. Stan ------- Date: Thu, 01 Aug 2002 20:47:32 -0000 From: "volzmechatronic" Subject: Holding Endmills: Part I Most of us have ancillary machine tools to support and maintain our shaper habit such as a drill press, a screw-cutting lathe, and a milling machine. Normally, the milling machines that we have are rather small with many of the spindles being the ubiquitous R8, invented by Bridgeport coinciding with the introduction of their "R- head" vertical milling attachment, or the also very common MT3. Probably the most used type of cutters are endmills with 3/8-inch and 1/2 inch shanks predominating. How to hold these endmills is the question. Forrest Addy, Machinist Emeritus, when asked that question over a year ago, responded with the following article comparing the pros and cons of using normal spindle fitting split-spring collets or end mill holders/adaptors: http://www.practicalmachinist.com/ubb/Forum8/HTML/000021.html In Part II of this thread I'll discuss some alternative end mill holding methods. Topic: Holding endmills- collets or end mill holders ? [WWW.PRACTICALMACHINIST.COM HOME MACHINE SHOP FORUM] posted 04-14-2001 To "which is better" question Forrest Addy replied- I run endmills in my R-8 collets all the time. That's what they're for. A collet wears more or less concentric whereas an endmill holder wears away from the setscrew. Collets are cheap. When they wear out you throw them away. When the spindle collet taper wears out you regrind it right in the machine. The only time I use my end mill adapters is when I need a little extra reach past an obstruction. When people tell you running endmills in collets is bad, smile politely but think "BS". If they persist with specious justification employ the "To each his own" or "Go piss up a rope" option as the situation dictates. How end mill holders wear posted by Forrest- Nearly all endmills these days have the familair Weldon shanks - a sraight shank with one or two flats for a setscrew. The Weldon shank is a compromise. While it's a vast improvement over the Brown and Sharpe taper shank (1/2 per foot) in retention (taper wedging action Vs set screw), the Weldon shank also requires a few tenths clearance with the holder merely to insert the cutter. The Weldon shank essentially a cantilevered shaft held by a set screw. The cutter in the work deflects under load to a rainbow shape concentrating its force on the edge or the tool adaptor bore. Grip a new pencil in your left fist and move the end of the pencil in a circle. Feel the stirring action in your hand. This stirring action is a rough analog of the Weldon shank in a set screw style tool adaptor. Bell mouth wear progresses from the mouth of the adaptor bore to the opposite side from the set screw. Here the nearly circular stirring is modified by the clamping action of the setscrew to a back and forth motion causing the mouth of the adapter to wear elliptically and the bore opposite the setscrew to wear as well. As wear progresses, the cutter moves eccentrically and to a small angle away from the setscrew until the tool adapter cuts on one side for light cuts and drags at a significant angle limited by elastic deflection of the cutter itself and the increased and non-circular wear clearance in the adaptor. Most anyone using a setscrew adaptor has noticed a brown smear on the endmill shank after a session of heavy milling. This smear may be powdery or greasy depending if the work was cut dry or with coolant. It's a vivid reddish brown if dry and dark brown if oily. The brown stuff is fretting corrosion products - hard steel worn by heavy cyclic pressure into the finest powder and oxidized in the adaptor's clearance space. You also see the same products in ball bearing bores and around failed ball bearings. So setscrew milling adaptors do wear. The wear is slow at first but progressive with heavy cuts and time. I was issued four new 2" shank Sonnet bull nose adaptors for a special close tolerence job on a Gray 4 head planer mill. There was a lot of stock to rough off using "corncob" roughing endmills then finishing with extension straight flute and some formed cutters. I checked the endmills when we started and they ran within 0.0005 on all teeth. Within two weeks of round the clock operation, the freshly resharpened cutters were running out 0.003" on the exposed shank and 0.007 4" out. You could watch the bead of coolant at the mouth of the Sonnet adapter pump in and out with the forces on the cutter and the action of the bead indicated the influence of the set screw. The endmill shanks were Rc 55 (pretty damn hard) and the Sonnet bullnose adaptor was Rc 50 (damn hard) but still the adaptors wore out in only 2 weeks of heavy but not abusive use. This lead to an examination of the 2000 or so 50 MMT Weldon shank adptors in the tool room. Over 90% were shot. Not a little bit shot but a lot shot - some having 0.020" bellmouth. Collective recollection over past unaccountable errors by good machinists and very expensive work spoiled lead to speculation on the role of all these years old and worn out endmill adaptors in the shop reject rate. $70,000 of emergency funding spent on new adaptors lead to a reduction of several hundred thousand dollars in the shop reject rate over the next year. The rate slowly increased as the adaptors wore. Therefore: set screw milling adaptors for Weldon shank endmills do wear. Moving on to collets. They wear as well. A collet bore in endmill service wears bell mouth at both ends but more at the mouth that the other end. Collets have a fixed bore length. Larger sized collets have a shorter diameter to length therefore larger Weldon shanks have a shorter grip to resist proportionately greater cantilever loads. Thus, larger collets wear far quicker. Collets wear bellmouth on both ends something like an hourglass until there's only line grip near the center of the bore instead of a full cylindrical grip. Futher use exacerbates the wear until the stirring action and the pull of the flute helix slowly drags the cutter from the collet no matter how tight you wrench the draw bolt. Because the wear is distributed by a collet's circumferential grip, the cutters run more concentrically compared to a setscrew holder where the wear is concentrated eccentrically by the setscrew forcing the cutter off center as it follows the wear. One only has to compare the stiffness of the grip of a new 3/4" collet with a worn 3/4" collet. Grip an 8" long piece of 3/4" drill rod so 6 3/4" sticks out. Torque the drawbolt for consistancy. Set an indicator near the end of the drill rod and apply a known force with a spring scale - say, 100 lb. Compare the deflections of worn Vs new. Note the magnitude. I suspect this is the basis of Jeff Park's bad experience with endmills in collets working their axially. Maybe he will comment. Most older machining centers using straight shank tooling use spindle collets with an annular relieved bore. The relieved center gives the collet longer life. Erikson and other makers of high quality spindle tooling are all very well aware of the dynamics of gripping endmills. They've provided ingenious countermeasures against the effects of wear in their excellent but expensive tooling. Unfortunately the R-8 tooling most of us are stuck with is designed for much lighter service and smaller overhung loads. An R-8 spindle with its small, short taper and clearanced upper fit is not a good choice for modern machine shop envirnment imposing relatively large overhung loads like milling with large long milling cutters or worse, the 4" carbide face mills touted (I love them) for turret mills. The R-8 taper soon becomes hour-glassed and the upper bore suffers from countless tool changes. There's no cure for the problem of spindle wear short of a 30 or 40 MMT retrofit or vigilence and an occasional regrind or upper bore sleeving. ------- Date: Tue, 01 Jan 2002 11:39:36 -0600 From: David Robertson Subject: Re: Modifying /Making Collets? 12/31/2001, you wrote: >It is also very easy to make "Tween" size collet bushings for that odd >drill bit or rod size from brass rod. I usually make them from 1/4" rod >drilled to the desired size and then slit them right in the collet. For these insert collets... couldn't you just make a single slot down the side rather than the way you have done them? Dave ------- Date: Tue, 1 Jan 2002 18:58:13 -0700 From: "Steve" Subject: Re: Modifying /Making Collets? Hi Dave, Probably could! I just put the same slotting arrangement as the collets and align the slots when using them so they are in effect an extension of the collet. I don't know the engineering reason for choosing two slots over one, or four slots over two, but since the collets have eight slots I figured I'd match my bushings to them. Brass is relatively flexible, and might not *need* the same number of slots, but it doesn't take much time to cut them. I probably spend more time finding the saw and tightening the blade than actually cutting the slots. The nice thing about the brass bushings is they are really simple and fast to make. Any odd size drill bit or round stock can quickly be "bushed" so it will fit in a standard collet without wasting a blank collet. Steve ------- Date: Fri, 04 Jan 2002 19:00:20 From: "Victor Bitleris" Subject: Re: Modifying /Making Collets? Just recently, I had to make a collet to fit a 3/32" rod. What I did was used a blank collet, available from Taig tools, center drilled the starter hole, drilled through with a 3/32 bit and then used a jewelers saw to cut the "slits". This was somewaht tedious as there is no real good way of holding the collet. I drilled some holes in a block of mild steel to assist in supporting the collet while I sawed. The hardest part was getting it started properly. If someone has a better way of slitting, please let us know. Regards, Vic Bitleris ------- Date: Fri, 04 Jan 2002 14:23:20 -0500 From: Larry Richter Subject: Re: Modifying /Making Collets? Well, I imagine a razor saw could be used in some way. X-acto, Zona, about a dozen brands around. Some very thin saws with small teeth available from the x-acto. Forget the handle. Less fragile than a jeweler's saw, though I don't see one cutting hardened anything well. They cut brass and anything softer forever. I have some decades old. If you mounted the unslit collet in the cross groove of a vise, and glued or screwed the saw blade flat and horizontal to a wood block of the right height, you could maybe hold vise with one hand and move block with the other. Probably get a fairly even cut and a rest from blade changing. ------- Date: Fri, 4 Jan 2002 21:13:54 -0500 From: "defex" Subject: Re: Modifying /Making Collets? you could put a dremel bit or some other thin saw in the jaws/collet on the lathe and somehow mount the piece on the cross slide. then you could just feed it in. the slot would not have a flat boottom but in that case i think it might make it work better...cutting oil!..clamp tight! ------- Date: Tue, 05 Feb 2002 14:01:17 -0500 From: Ken Jenkins Subject: Re: Making end mill arbor on mill > Date: Tue, 05 Feb 2002 08:31:47 -0500 > From: Al Schoepp > Subject: Re: 1/2" end mill adapter > I would like to make a few of these up but don't have access to a lathe, > any suggestions on how best to do it with just a mill. I do plan on making > a flycutter which I can do on the mill. I'm not saying it can't be done, but I wouldn't try it. Unless you are absolutely meticulously perfect you're going to get runout. Ken J. ------- Date: Tue, 5 Feb 2002 13:11:28 -0600 (CST) From: Tom Benedict Subject: Re: Re: Making end mill arbor on mill Say, this raises a question: Let's say you've got a Taig lathe and a Taig mill. You make your arbors on the mill, then transfer them to the lathe. What kind of gurantee do you have that you're going to get reasonable run-out? Are the mating surfaces good enough you can relax and cut metal, or would it be worth the time and effort to stick your mill spindle on the lathe bed, and use that as a headstock? Tom ------- Date: Tue, 05 Feb 2002 19:20:52 +0000 From: Tony Jeffree Subject: Re: Re: Making end mill arbor on mill I would doubt very much whether arbors will be "spot on" when transferred between machines, so it may well be worth swapping heads to do this & marking your arbors as to which machine they are for. The other relevant question here is whether the runout would be repeatable after removal/re-fitting the arbor *on the same spindle*. My guess is that it won't be repeatable to better than a thou - anyone tried measuring this? Regards, Tony ------- Date: Tue, 5 Feb 2002 11:32:39 -0800 From: "Nicholas Carter and Felice Luftschein" Subject: Re: Re: Making end mill arbor on mill One thing, the register portion of the blank arbors is a bit relaxed - you could cut the register portion off and bore a new register that was a tight fit on the spindle register - that would increase accuracy. ------- Date: Tue, 5 Feb 2002 13:42:00 -0600 (CST) From: Tom Benedict Subject: Re: Re: Making end mill arbor on mill On Tue, 5 Feb 2002, Tony Jeffree wrote: > I would doubt very much whether arbors will be "spot on" when > transferred between machines, so it may well be worth swapping heads > to do this & marking your arbors as to which machine they are for. > The other relevant question here is whether the runout would be > repeatable after removal/re-fitting the arbor *on the same spindle*. > My guess is that it won't be repeatable to better than a thou - anyone > tried measuring this? Nope, but I've still got some blank arbors, so I think I see an experiment coming. ;) Well here's another question: On a raw blank arbor, how good are the mating surfaces. In particular, how good is the flat that mates up against the shoulder portion of the spindle? (This is the area I wound up facing off on my Jacobs chucks, which improved runout by several thou on each chuck.) Keeping the answer to that question in mind, how would you turn a blank arbor into a mill holder with as little run-out as possible, taking it step-by-step. For example, if you distrust the mating surfaces on the raw blank arbor, a first step might be to center it up in the 4-jaw and face off the back end of the arbor. A second would be to mount the arbor on the spindle and... Tom ------- Date: Tue, 05 Feb 2002 20:19:30 -0500 From: Al Schoepp Subject: Re: 1/2" end mill adapter >Al;Mount the arbor on the quill. Hold a center drill vertically in the >vise. Locate the drill on the center of the arbor. Lock the table in >both axis. Enlarge to a bit less than final hole size by step >drilling. Once almost to size, either ream or finish to size with a >boring tool held in the vise. If boring, set the tool with the tip dead >on the X or Y axis. Unlock only that axis and move the table to control >the boring tool depth of cut. Cross drill and tap for set screw, deburr >the inside of the set screw hole - a length of drill rod with the end >cut to a sharp 20 degree tip as in a paternmakers reamer makes this >easy, or a ball stone or burr on a dremel tool does the job nicely. >Nice thing about this approach is that you are sure the bore in the >arbor is dead on the quill centerline. Stan Stan, I would think the tricky part with this method would be aligning the drill bit with the center of the arbor. At the speeds it will be used at and the desired purpose it must be very accurate. That's were the lathe would be handy as the head and tailstock should already be aligned if they are properly setup. For now I've decided to get a Sherline 3/8" endmill holder. I would think that this would be something that people selling accessories for the Taig would take advantage of. I would rather buy and endmill adapter than try to make one without a lathe. Al ------- Date: Tue, 5 Feb 2002 17:51:59 -0800 From: "Nicholas Carter and Felice Luftschein" Subject: Re: Re: Making end mill arbor on mill Forrest feels it would be hard to guarantee runout on a manufactured one, plus he didn't realize at first that the Taig mill could handle big endmills. I have made a few for my customers and it can be a pain - the $30 sherline sells theirs for is about right as a retail price, or course you can spend 20 minutes making one out of the 1132 and come out ahead. What I'd really like is an ER collet setup for the mill that could handle 3/8" collets. ------- Date: Tue, 5 Feb 2002 21:16:42 EST From: tadici283x~xxcs.com Subject: Re: Re: Making end mill arbor on mill I have solved the runout problem, which drove me nuts, I am not the one who started this thread but though I would write since I have not written too much lately. After many attempts to make an endmill holder that would run true, I decided to sit down and think it out, and what I came up with was even though the end mill holder (arbor) was carefully undersized drilled and reamed to finished size it still had runout, granted we are splitting hairs here but it was off, what I did was to drill at first 3 holes and now 5 holes radially and tap them 1/4x20, the end mill is then mounted, adjusted, and never removed until broken or wears out. I buy arbors for each size and tool and do not interchange them. The land on the endmill gets a little bit longer set screw and there is a counter set screw on the other side. I like clean and straight machining so all holes are drilled with my CNC rotary table and then a finish "clean" up cut made via lathe. I do get some arbors that are not as straight or seem off center and sometimes they take a surprisingly large cut to get on center, but do to the low cost of them ($2.00 or so) I can make all kinds of tools. Recently I made an engine turning cutter, for making those nice engine turnings on old watches and pocket watches, with the aid of perfect movement via CNC the pattern is very pleasing, so there is little limit with those wonderful arbors. Best regards, Chris of Bradenton FLA ------- Date: Wed, 06 Feb 2002 01:00:40 -0500 From: Stan Stocker Subject: Re: 1/2" end mill adapter Al; Probably a good choice if the em holder from Sherline fits up well! But if you think about it, you find center all the time in milling operations, to better than a thou with care. You just have to think upside down, picking up the edge of a cylinder held on the spindle with the tool on the table. The quickest way to get to dead center on a cylinder is to pick up an edge close to the max on the y axis, then move half the workpiece diameter + half the edge finder or pin/drill diameter in. Pick up an X axis edge, move half the distance + half the tool. Repeat once again starting with the y axis then the x axis and you'll be dead on center, to better than a thou with no fancy footwork required, just the usual keeping track of backlash and reading the dials in good light. Gotta love trig, plug in fairly good starting conditions and the solution point converges rapidly! By boring to final size rather than drilling, any off center or out of round nature of the hole is removed, as you are automatically referenced to the axis of rotation. For precision hole making on a lathe, I'd never use the tailstock to hold the drill except to open up the hole leaving 10 thou or more for boring. The boring bar is held on the carriage. Even if you have your tailstock dead on center, the variations on all but the most expensive drill chucks over the range of the chuck will toss you a thou or two, maybe more, off center. You could pull this stunt off holding the arbor in a vise, but this looses the self aligning nature of the boring operation. I have bored cylinders on the mill better than a half thou concentric with the turned OD, but the setup requires a tenths reading indicator and an appropriate way to hold the indicator to the spindle, not to mention very good V blocks to get things truly perpendicular. Easy on an R8 sized mill, using an Indicol holder, but likely not so easy on a Taig mill. You'll need a spacer behind the Sherline em holder I think, as their spindles don't have a register. I know this effects using Sherline chucks on the lathe, but don't know if this applies to the end mill adapters. Please post how it works out for you. Cheers, Stan ------- Date: Wed, 06 Feb 2002 13:02:04 -0500 From: Stan Stocker Subject: Re: 1/2" end mill adapter The register is the unthreaded portion between the shoulder of the spindle and the threads. This is a contact area that is a very close fit with the unthreaded area on the headstock end of the chuck/arbor/whatever. Rather than relying on the thread wedging action to be self centering, this area provides centering of whatever you are mounting to the spindle before the threads begin to tighten. Done right, a register reduces runout quite a bit. If the register to chuck bore is a sloppy fit, it doesn't do much for you, as is seen on the chucks provided with 9x20 lathes. On larger lathes with threaded spindles, the register is often larger than the OD of the spindle threads, so to make a backing plate, you bore a stepped bore, one the minor diameter of the spindle threads all the way through, and a larger bore to mate to the register. You then cut the internal threads, mount the backing plate, and finish up the machining on the part of the back plate that the chuck mounts to. Stan ------- Date: Fri, 08 Feb 2002 22:23:12 -0000 From: "buchnerb" Subject: Making a Dovetail Cutter As part of my effort to learn to use my Sherline mill and lathe I purchased some of the PM Research steam engine and machine tool kits. I have the mill and the shaper kit. The shaper calls for a 60 degree dovetail that is .250 wide across the bottom. I have searched for a cutter that small to no avail. The gentlemen at PM research said I would have to make one. I also need to make a small T-slot cutter for both tools. What is the best method to do this. My initial plan is to turn a 60 degree reverse cone .250 wide on a piece of water hardening drill rod. Then mill a flat on each side to produce a paddle shape. Then grind back the sides a little to produce a cutting edge and then harden it. Is there a better method? Bruce Buchner ------- Date: Fri, 8 Feb 2002 20:27:50 EST From: aermoterx~xxaol.com Subject: Re: Making a Dovetail Cutter Bruce, I have the mill kit from PM and have used a 45 degree cutter on all of it. I got the cutter from sherline. Another thing I have done on the kit: they call for a 5-40 LH thread on the table. I used a RH thread on it and then put the one 45 degree gear on top instead of the bottom so the table will rise and decend like it should. As far as the T-slot cutter goes, I used an 1/8 end mill and ground it down to the right shape. Not saying that this is the right way to do it but it worked for me. Tim Christoff Basehor, Ks. ------- Date: Wed, 20 Feb 2002 15:31:51 -0000 From: "paul_probus" Subject: Re: Honing TiN inserts? And triangular insert question. Randy: The best reference for ISO inserts is the MSC catalog. It is free and can be ordered through MSC's web site. It has a lot of tooling for HSM's and industrial machine shops, but it would be worth getting just for the carbide insert reference information alone, IMHO. It is a large catalog and you'll need a hand truck to cart it around ;). As far as the inserts you already have, the TT-221, I, too, have those inserts and have found them to be very good and leave very good finishes, but then I was using them on a Hardinge lathe, not a sherline. Looking up in MSC, the inserts appear to be ISO, TCMT-22X, if my memory serves me correctly (it has been a while since I have looked them up and I don't have my MSC book with me). The closest inserts to work in those tool holders would be (again from memory) TPMG(or is it TPMT?)-22X inserts. They probably will not fit, however, since they have a larger side clearance angle then the TCMT inserts. I believe using the TCMT inserts in a TPMG toolholder will work. You are correct, however, the TPG inserts will not work because they do not have a center clamping hole. If you go to Ted Edward's web page (if it still exists, I don't remember the URL), he recommends using TNMP inserts because you get 6 cutting edges because the insert is ground with a positive cutting angle into the chipbreaker, while the TCMT/TPMG inserts only allow three cutting edges per insert because the insert is ground for the positive cutting edge. The reason for this is that the TNMP inserts use a negative rake insert holder which allows the insert to have straight sides because the holder is angled to provide the proper clearance. The TCMT/TPMG inserst use a straight insert holder and the inserts are ground for the edge clearances. Its easier to see with a picture and I believe Ted has them on his site explaining the difference between positive rake inserts and negative rake inserts. In the meantime, if I am wrong about the TPMG or TPMT insert designation and knows what inserts I am talking about, please post the correct info. since I won't be able to post a correction until tomorrow. I would prefer that Randy gets the correct info. sooner than that. Paul BTW, the TT-221/222 inserts I have used do horribly on interrupted cuts. Useful life goes down to near zero. I have used the Diamond Toolholder for both interrupted and uninterrupted cuts and prefer the inserts for uninterrupted cuts and the DT for interrupted cuts. As a hobby machinist, I believe it is nearly impossible to get away from HSS toolbits and when they are needed for lathe work, I recommend getting or making something like the DT. The DT is expensive for what it is, but it works fine for me. ------- Date: Wed, 20 Feb 2002 09:11:28 -0800 From: "Craig Libuse" Subject: Re: Re: Honing TiN inserts? And triangular insert question. Its easier to see with a picture > and I believe Ted has them on his site explaining the difference > between positive rake inserts and negative rake inserts. An illustration of positive vs. negative rake can be found in Sherline's instructions for using carbide inserted tip tools at www.sherline.com/7600inst.htm or www.sherline.com/carbtool.pdf. --Craig Libuse Sherline Products Inc. ------- Date: Wed, 20 Feb 2002 11:00:04 -0800 From: "Craig Libuse" Subject: Re: Re: Honing TiN inserts? And triangular insert question. > Unfortunately the Sherline web site doesn't give the alphabet soup > designation for the holders nor for the inserts... -Kevin Kevin, Designations are as follows, although naturally we'd prefer you buy them from us... 7605 (55°) insert for 35° offset 2256 (RH) and 2257 (LH) holders = DPMT 21.51 2AVC29 7612 insert for 55° neg. rake tool holder (7610) = DNMG-331 (Listed in instructions) 7622 insert for fly cutter (7620) = CPMW 32.51 (Listed in instructions) Craig Libuse Sherline Products Inc. ------- Date: Sun, 10 Mar 2002 14:54:09 -0500 From: "Daniel J. Statman" Subject: Great Source for Miniature Endmills If anyone is looking for carbide ballnose and flat endmills in extremely small sizes, go to: http://www.discount-tools.com I just ordered some 0.015" and 0.020" ballnose carbide endmills and they arrived in 2 days and work beautifully to cut titanium. Here is a sample of what they can do: http://members.rennlist.com/statmandesigns/Style-GK003-Blue-Large.jpg The milled pattern was cut with a 0.020" ballnose 2-flute endmill in three passes each of depth 0.006" for a total channel depth of 0.018". The pattern is then anodized to the blue color. I have no affiliation with discount-tools.com, just a VERY satisfied customer. They probably have good deals on other tools, but I haven't looked yet. I have had no problems with backlash. I measure it and compensate for it, my mill has 0.002" backlash in the X-direction and 0.05 degrees on the rotary table. It is impossible for a 0.020" diameter endmill to cause enough force on the mill to see any effects of backlash. My CNC controller software uses the most basic form of backlash compensation and it seems to work well enough for me. know, continuous velocity contouring is something that I wish I had, but I can live without it for now. Daniel J. Statman, Statman Designs www.statmandesigns.com ------- NOTE TO FILE: The discussion "Drilling problem" is covered in the Drilling Tips file. It has wandered off topic a bit and entered the question about hardening collets (or not) and is continued here. ------- Date: Mon, 11 Mar 2002 23:57:29 -0000 From: "martello_nick" Subject: Re: Drilling problem > Not forgetting that hardening will slightly change the dimensions > and/or the shape of the taper. This is exactly my question. I am also trying to make a collet out of cold-rolled hence the basic info about cutting tapers that Jon, Hank and Jude replied to. I'm now ready to cut the taper at the head of the collet to fit the cup I made for the spindle. Once the collet is finished, I plan to grind it by rigging up my dremel to the cross slide. So, I guess you should heat treat after you grind it down? Assume the heat treating is necessary if you want the tool to last for a while? Nick in Atlanta ------- Date: Tue, 12 Mar 2002 06:34:11 +0100 From: "jcgerb" Subject: Re: Re: Drilling problem Nick, No you should grind to the final dimension after the heat treatment. Any heat treatment will slightly modify them. How much the piece will deviate is depending from the quality of steel you have been using. That is what manufacturers tend to try not to do because it is expensive, but no precision made part can be let without retouching it. If you want to grind before, you will have to grind afterwards if you want to get an exact fitting piece. I do not think that I have a general doc in English about it. May be some readers could send you something for your understanding what happens with the steel when heat treated. Jean-Claude, Switzerland www.homestead.com/turnandmill ------- Date: Mon, 11 Mar 2002