Methods for holding workpieces for machining with various power tools. WORKHOLDING can refer to parts held for turning in a lathe, or milling on a mill, or milling on the cross-slide of a lathe, or use on a shaper. Or for doing an operation on the object with any other machine, or even a hand tool. The main workholder on the lathe is the chuck. Often a lathe chuck is also mounted on a mill table so that milling operations can continue without ever taking the lathe workpiece out of its chuck. Or the chuck can be the best workholding choice for a milling operation. In any case, please also read the various chuck files on this site for good ideas on chuck use. Lathe faceplates and collets are also very handy for holding parts for other machine operations, so read those files too. 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. 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(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. ====================================================================== From: Les Grenz Date: Mon Nov 22, 1999 8:42am Subject: Re: workholding on sherline mill Hi Kirk - I have had excellent success mounting flat stock using an industrial strength double coated tape. I have used it on the Sherline mill table, rotary table, lathe face plate and even for larger things on my Bridgeport. I can't tell you the brand since I've had it for some time and it is not labeled. However it is like a thin clear acetate with a red backer. Les ------- From: Rich Dean Date: Mon Nov 22, 1999 4:27pm Subject: Re: workholding on sherline mill Kirk wrote: > Thanks for your response Les. I was looking thru my MSC catalog for > something like Ron Lederer suggested and came across Mitee-Bite > products. These are cam operated side holders which look interesting > except they dont seem to make anything small enough for a Sherline mill > and they are *expensive*. But they also make an adhesive product like > you described. This also seemed interesting, it was described as a > thin (.005) adhesive with peel off coatings. I appreciate your input > and wonder if this is what you are referring to. Don't think it was > too expensive. Kirk, Les, I use the Mitee Bite *Mitee Grip* paper. It is an excellent workholding device. The paper is very thin and coated with a hard wax both sides. To use, place the paper between the part and your holding surface, clamp and warm up to about 180+ deg F. Cool down to machine part then warm up to release. Clean wax off with mineral spirits while warm. Mitee Grip is sold by J&L (800-521-9520). 70° in Atlanta $ sunny..........Rich Dean ------- From: Gregory Gagarin Date: Sat Nov 27, 1999 5:49pm Subject: Re: workholding on sherline mill Kirk: As you have seen from the many helpful responses to your post, workholding is a common problem requiring a lot of personal invention. With no previous training, I started my Sherline experience a little over a year ago and have confronted your dilemma many times since. Lots of people helped (and continue to help) me so thought I would offer a couple of ideas. If clamps, the vice or a chuck won't work, think milling plate. Rarely does my work lend itself to direct attachment to the table so I end up making a CHEAP milling plate. I always try to make the plate as extendable to other uses as I can and after a while you build up quite a collection. Then you can usually find one of them that will work directly, or with slight modidication, for your new task. The big advantage to a CHEAP milling plate is that you can drill or mill into it without heartburn -- this saves a lot of creative clamping, reclamping and parallel bar maneuvers. Where to get CHEAP material for a milling plate? I think one of the best investments I have made since I began this game was an impulse Aluminum purchase from "www.mousebar.com". I knew nothing about Aluminum types or sources and happened to pick up their name on internet. They sell a 30 pound box of random Aluminum cutoffs for $100 delivered. It turned out that they get their Aluminum from a local Die manufacturer. It's "FORTAL" Aluminum,7075-T651 type (slimilar to to what Sherline calls their high priced spread used in their 3/8" negative rake carbide insert tool holder) and is beautiful stuff. It's hard (comparable to mild steel), machines easily to a mirror finish, stays bright,less sticky than 360, available in a wide assortment of sizes (only rectangular -- no rounds) and very affordable. I now am into my second box and use this material for most of my projects as well as all of my fixtures. They have a large list of individually available sizes (at a slightly higher price) and are knowledgeable and helpful -- 1-888-466-8732 (Jim). I like the stuff so much that I even turn my own rounds. Once you have a mill plate everything everyone else suggested applies. One new idea is worth considering. WR (Bill) Smith sells books and videos on several subjects -- you have probably seen his posts and comments from others on his materials. I bought two of his videos and one of his books and in that material he discusses at length the use of super glue for workholding on the mill and lathe. He makes a milling plate with groves specifically for use with super glue. Once the stock is glued down you can mill the top surface and all edges and drill anywhere without moving your stock. When complete, you heat the milling plate to break the super glue bond and clean with acetone. The milling plate is ready for future use. Bill is also very helpful on the phone and this is only one of his many tips and techniques. Hope you find this info helpful. Greg ------- From: Date: Thu Aug 10, 2000 11:35am Subject: ideas for hold-down set Hey everyone, Has anyone made their own hold-downs? I guess what I'm concerned about is using the right alloy or steel. The Sherline set is aluminum right? Is is stronger than T-6? and would T-6 be fine? Or should I just make a miniature set out of some 1/4" steel that I have? This seems like a real simple post, but I was wondering if anyone had invented some interesting hold-down setups? Ones that are not based off the Sherline models (the "L" brackets and $20 hold-down set). There are several projects I have where a jig mounted to the mill table would be the best since it would keep some delicate parts from possible flexing. Thanks, Jason ------- From: Keith Yundt Date: Thu Aug 10, 2000 2:02pm Subject: Re: ideas for hold-down set Jason, I have created a file folder in the "files" section with some pictures of some home-made clamp spinners that work with the Sherline clamps to make their use a little faster and simpler. The idea should work with any clamp, though. Keith ------- From: Ron Ginger Date: Thu Aug 10, 2000 2:21pm Subject: Re: ideas for hold-down set jasonspanglex~xxh... wrote: > Has anyone made their own hold-downs? I guess what I'm concerned > about is using the right alloy or steel. This is probably the most important area of mill work- how to hold the part. The clamps sold by Sherline are just one of many variations. Lots of work can simply be bolted to the table directly. A tooling plate is also very usefull- a scrap plate of aluminum to which the work is bolted, then the plate is bolted to the mill. This is handy when you need to mill down to an edge and dont want to cut or drill into the mills own table. Ive got several boxes of various hold downs, clamp bolts, etc. All made for one job, thrown in the drawer and maybe someday used again. So, there is no 'right' or 'wrong' material or form. Its whatever works for the job at hand. ron ------- From: Dan Gustafson Date: Thu Aug 10, 2000 1:50pm Subject: Re: ideas for hold-down set From: jasonspanglex~xxh... To: sherlinex~xxegroups.com > There are several projects I have where a jig mounted to the mill > table would be the best since it would keep some delicate parts from > possible flexing. Definately. The basic hold down set is very limiting and having a jig or fixture is necessary for a lot of projects. I recently bought one of the "Tooling Plates" from sherline, which is basically just a 1/2" x 4" x 10" piece of aluminum (6061?) that can be easily mounted to the mill table, but it has several pre drilled and threaded holes for the 10-32 screws used in the hold down set (or from the hardware store). I have done some milling on the tooling plate to customize it for my specific project and let me tell you, it can be MUCH more versatile than using the standard hold down set. You are no longer limited to holding down parts from the two slots in the mill table and in fact, with some modification you can hold down from anywhere you please. I dont know the exact price of the tooling plate as the retailer I bought it from gave me a single price quote for lots of accessories, but I think its around $30.00. In the future when I get the flycutter, I might just buy some 9/16" Aluminum and cut the surface flat myself so that I can make my own custom fixtures. That ought to be a lot cheaper. Dan ------- From: John D. Guenther Date: Fri Aug 11, 2000 3:55pm Subject: Re: ideas for hold-down set You are correct, the tooling plate makes all the difference in the world for holding work down. I beleive the plate is actually cast aluminum jig plate which is about $0.52 per square inch from Metalmart. I plan on making one that covers the full length of the table with holes for other work holding fixtures. John Guenther ------- Date: Fri, 5 Jan 2001 11:52:52 -0600 (CST) From: Tom Benedict Subject: Re: G code On Thu, 4 Jan 2001 ajkdfwx~xxaol.com wrote: > For all you CNC types out there ... I was just netsurfing and ran > across this very interesting site. They sell CNC mills and lathes, but > offered some free samples of G code as well and thought it may have > some appeal to some of the members of the group that are into CNC. Try > this URL ..... http://www.positiveflow.com/frecode.htm I haven't been > bitten by the CNC bug (yet) but this has piqued my interest. Take a look at some of the other parts of that site. Pretty neat! The gallery is most impressive. I was taking a look at their list of tools: http://www.positiveflow.com/tool.htm The last one on the list is really intriguing. It's listed as a "quick change tool system" for a mill. I think the same thing could be accomplished by getting a bunch of blank arbors, drilling and reaming them to size, and permanently (or semi- permanently) mounting all of your end mills in their own individual arbors. What it would buy you is that you could essentially set all of your end mills to the same height. So if you switched from a 1/8" mill to a 1/4" mill, you wouldn't need to re-set the surface height. Right now I've been using a single arbor with a 3/8" reamed hole in it and a set screw as an end mill holder, and have been removing and replacing whenever I change mill sizes. But I've got only six end mills and nine unused blank arbors. Making individual holders for each of the mills would be pretty straight- forward, and shouldn't take more than an evening to do. Can anyone see a problem with doing this? If I mount each tool in its own holder and then set them all to the same height, it seems like it'd be a good thing... right? Let me know if you think it's a bad idea (or a good one, for that matter.) Tom ------- Date: Mon, 15 Jan 2001 13:06:55 +0000 From: Tony Jeffree Subject: Re: Re: Absolute Newbie Question At 12:25 15/01/01 +0000, you wrote: >How do I put in the dead center? In a chuck? That seems to defeat >the idea that the dead center is centered although I could use a dog >with it. I have a face plate (I evidently bought a lot of stuff in >1979) with a slot in it but do I need a collet or what? You could make a dead center by (for example): - Holding a short length of 1/4" rod in a collet; or - Using a chuck to hold a short length of 1/4" rod; or - Modifying a Taig "blank arbor" screwed onto the spindle nose; or - Modifying a Taig drill chuck arbor; or - Drilling a hole in a blank collet & inserting a piece of rod with Locktite to secure it. I'm sure that others will have more possibilities to add to this list... Generally, for best accuracy with a dead center, the taper on the center is re-cut in situ each time it is used, thus ensuring that the point of the center is always exactly on-center, regardless of the (in)accuracy of the device used to hold the center in position. This is less of an issue with spindle noses that have an internal Morse taper, as a well made center can be re-fitted with reasonable accuracy if witness marks on the center & spindle are used to make sure that the center is always re-fitted in the same position; however, even then, for really critical work a good machinist will always re-cut the taper after fitting the center. Hence, dead centers for use in the headstock are generally made from "soft" (i.e., not hardened) steel, so that they can be machined easily. Hardened centers are generally used only in the tailstock. Regards, Tony ------- Date: Mon, 15 Jan 2001 23:42:34 +0000 From: Tony Jeffree Subject: Re: Re: Absolute Newbie Question At 16:33 15/01/01 -0600, you wrote: >But doesn't the faceplate screw on the external headstock threads? thus >using collets or blank arbor is not possible as a simultaneous operation. >Seems like you have to have one that fits in taper.. I thought of making >one to screw on my drill chuck mounting arbor (for headstock). That would work. With the "blank arbor" approach, you could attach an arm to the arbor to drive the lathe dog. With the collet approach, you could make a catch plate to fit over the flats of the collet closer. >What do the rest of you do for a dead center with faceplate. The obvious way (other than the options already discussed) would be to mount a centre on the faceplate using the T-slots. >One thing I have seen is to use the three or four jaw chuck holding dead >center and have lathe dog catch on jaws of chuck. This seems like easy >solution but point on dead center will have to be "re-trued" by taking >light cut off each time it is used. Arguably, as I said in my earlier post, you need to do this anyway for accurate results. If you're not concerned about a small amount of runout, then its a lot easier just to use a collet or true up the soft jaws of the 3-jaw. Regards, Tony ------- Date: Mon, 15 Jan 2001 16:18:48 -0800 From: "Nicholas Carter and Felice Luftschein" Subject: Re: Re: Absolute Newbie Question Original Message ----- From: David Robertson To: > One thing I have seen is to use the three or four jaw chuck holding dead > center and have lathe dog catch on jaws of chuck. This seems like easy > solution but point on dead center will have to be "re-trued" by taking > light cut off each time it is used. This is what they teach at the local community college. If you do true it up each time you use it then you are guaranteed total concentricity. ------- Date: Fri, 26 Jan 2001 21:09:21 -0600 From: "Jeffrey C. Dege" Subject: Dead Center On the subject of making a dead-center - I took a 3" piece of 3/4" rod, drilled and tapped a 3/8x24NF hole, screwed up the threading, took another piece of rod, drilled and tapped, broke the tap, bought a new tap, then took a third piece, drilled and tapped that successfully. (This was made difficult because the drill chuck wouldn't hold the 21/64" drill bit, I center drilled then stepped up to 1/4", then hand drilled from there. The chuck adapter made an easy and solid mount, for both drilling and tapping, screwed into a 2x4 wall-stud.) Then I mounted the drill chuck arbor, screwed the piece of rod onto the end, and turned it down to make the dead-center. The result looks to work very nicely with the face plate. Which wouldn't be true of a center held in a chuck, or one which threaded onto the spindle. And will require less effort to replace that the centers that involve soldering a rod through a blank collet. (And if you turn the center every time you use it, as I've seen recommended, you're going to need to make a new one with some frequency.) ------- Date: Wed, 31 Jan 2001 15:30:48 -0500 From: ron ginger Subject: Re: t-slot cutters Marshall Pharoah wrote: > Does anyone have any idea where to get t-slot cutters sized > for the Sherline? Smallest I can find is 1/4". Make one. A bit of drill rod, some turning and mililng, then a bit of grinding, and you've got it. If you happened to notice at Cabin Fever our demo used an 'upside down' dovetail cutter. We needed to cut a dovetail (actually the notch on the whistle) with the large diameter up. One of our guys made the cutter. ron ginger ------- Date: Sat, 17 Feb 2001 16:34:04 -0000 From: gartner1x~xxhome.com Subject: Crosslide problem I've a problem that I hope someone can help me with. I have a 4400 lathe that's not quite a year old. I seem to be getting some deformation of the crosslide where the tool post attaches. The sides of the T-slot seem to be pulling up and closing together (I can no longer freely slide the tool post through this area) See a photo at: http://members.home.net/gartner1/Jack/Sherline1.jpg Anyone have any idea what's going on? Am I doing something wrong or do I have a defective crosslide? When tightening the tool post I don't believe that I'm tightening it too much. Thanks, Jack ------- Date: Sat, 17 Feb 2001 12:16:16 -0500 From: Bradford Chaucer Subject: Re: Crosslide problem It looks like you are either tightening something that is raised off the surface in the area around the T-nut or are doing something that is causing an upward twisting torque at that point. If you were clamping a flat block that is in contact with the cross-slide at that point, you should not be getting that deformation no matter how hard you tighten the bolt. Regards, Bradford Chaucer ------- Date: Sat, 17 Feb 2001 17:27:10 -0000 From: gartner1x~xxhome.com Subject: Re: Crosslide problem The only thing that I've ever used on the crosslide are the Sherline tool posts. Could they cause this? Jack ------- Date: Sat, 17 Feb 2001 12:41:06 -0500 From: Bradford Chaucer Subject: Re: Re: Crosslide problem At 12:27 PM 2/17/2001, you wrote: >The only thing that I've ever used on the crosslide are the Sherline >tool posts. Could they cause this? Not unless something you are doing is causing it to lift on one side. Is the toolpost flat against the cross slide at the point where the slot lip is deforming?? Craig Libuse from Sherline monitors this group. You might send an email directly to him. He is quite helpful. Regards, Bradford Chaucer ------- Date: Sat, 17 Feb 2001 10:40:05 -0800 From: "Cliff Griffin" Subject: Re: Crosslide problem I'll bet anything that your bolts are too long, causing them to extend through the bottom of the T-nut and push the T-nut up through the top. Simply over tightening the bolts shouldn't do that, because you would be pulling two flat plates together. Check your lengths, and let us know! Keep in mind that the aluminum that you are working with on the cross slide is less that 1/8"--it's only .100" thick there. Cliff ------- Date: Sat, 17 Feb 2001 18:54:27 -0600 From: Custom Built Fishing Rods Subject: Re: Crosslide problem You should have been a carpenter Charlie, I think you hit the nail on the head. It looks like the post was installed without cleaning out all the chips, something you see a lot on production machines. Charlie Lear wrote: > On Sat, 17 Feb 2001 16:34:04 -0000, gartner1x~xxhome.com wrote: > >See a photo at: http://members.home.net/gartner1/Jack/Sherline1.jpg > A picture is worth a thousand words... well done! > I'd say that a) you are tightening it a bit too much, and b) what looks > like swarf is being trapped underneath the toolpost and pressed into > the surface of the cross slide, which is squeezing the metal at the top > of the t-slot and causing the very small reduction in width. >> Are you 100% sure that the T-nut is binding on the diameter, and not > underneath? > Take the nut off the toolpost and slide the nut through the slot - you > may want to take off the handwheel and shine a torch up the slot while > you do this, I've found that swarf in the T-slot can jump on top of the > nut when you slide it in, and tightening the nut jams it into the top > surface of the slot. I use a stiff bristle brush followed by a small > bit of rag to clean out the slot every time I change a tool, and I'm > still not getting everything out. > Cheers Charlie > Charlie Lear, Melbourne, Australia clearx~xxsteammachine.com > Hutt Valley Model Engineer Soc. http://steammachine.com/hvmes > Eastern Bays Little Blue Penguin Foundation: same site /penguins ------- Date: Sun, 18 Mar 2001 19:39:13 -0000 From: "alfred piszcz" Subject: expanding mandrels Has anyone considered using tailpipe expanders for use as an expanding mandrel? I purchased three of them in different sizes with that use in mind. These also have quite a range of adjustment. True if it is ultra precision that you need this isn't for you, but if you just need to get a OD to a specific size -- especially with aluminum or PVC pipe, this might be a low cost alternative. Some fine tuning might be necessary such as putting a center hole in the end of the mandrel to use with a live center for better stability. I purchased mine from Harbor Freight and caught a couple of them when they had the half-price sale. The fellow that needs one in a hurry could buy it at a local auto parts store but it might cost him a bit more. ------- Date: Sun, 18 Mar 2001 21:29:23 -0600 From: "J Tiers" Subject: Re: Re: Lathe Upgrade/WTB Mandrel Snip: >> it up. One thing I`d really like to get right away, >> for my new lathe is an expanding mandrel. I would >> need one that would hold a tube with a 1.5" ID >> Can someone suggest where to find one of these, >> or maybe someone here have one to sell? unsnip If you can stand an "arbor", J&L have expanding arbors for 1 1/2 inch at $41.30. This does not expand as much as the mandrel, but may do you OK if ID is close to 1.5". J&L part ARB-01500B Jerry ------- Date: Mon, 26 Mar 2001 08:01:44 -0800 From: James Eckman Subject: Re: Accessories for the Taig Mill >From: "David Robertson" >Could you elaborate...what are spherical washers and what are they for? Sure, they are washers with bearing surfaces that are not flat. If you cut them in half and traced the shape that the bisected part, you would see that the shape is part of a circle. There is a male part and a female part. They are used as spacers when your clamping uneven parts. the two halfs slide against each other so that the clamping surface and the nut don't have to be parallel. Nicholas Carter >> For studs I just whacked up a length of 1/4-20 threaded rod into convenient lengths. For the pressures that you clamp small stuff with, hardware grade fasteners seem adequate. For t-nuts I bought a length of 1/2"x1/4" CRS, whacked it up into 3/4" lengths and tapped 1/4"-20 << I've some of those tapped 10-32. I use hardware store nuts, a good grade though... One advantage of making your own studs instead of using allthread is that if you have one very short end as shown, you can't screw it into the table and possibly damage it. Most of the stuff is made from shop scraps or CRS which is cheap, none of the projects took over a day's worth of time. For example, the washers took about the following time: Grind form tools, 15 minutes using ball as a guage Set up lathe with 2 tools, drill and stops set, 10 minutes Each part, 30 seconds or so... Deburring, etc. 30 seconds or so... The studs are almost as fast, maybe a 2-3 of minutes each. Hardware store studs in 1/4-20 are over a buck a piece! Jim ------- Date: Sun, 29 Apr 2001 05:47:39 -0700 From: James Eckman Subject: Re: taig vise [APPLIES TO ANY NON-MILLING VISE] > From: airwardenx~xxhome.com > I am trying to use the vise that came with my mill and I cannot > get it to quit pushing the piece of aluminum I am clamping in it > up. Is there some trick to using this vise so your work will stay > flat to the bottom? 1. Gently hammer it in with a rubber/leather mallet. 2. Try putting a piece of round rod horizontally behind the workpiece like this, possibly performing option 1 on it!: rod-> back jaw|O|workpiece|front jaw screw ////////////| | bottom | | _____________ Pardon the crude graphics... Yours, Jim Eckman -------- Date: Sun, 29 Apr 2001 10:42:33 -0700 From: "Nicholas Carter and Felice Luftschein" Subject: Re: taig vise This is why I generally recommend a "toolmakers screwless" vise for the Taig mill. They are available from ENCO on sale for between $40-$70 depending. The problem with the Taig style vise, and this applies to all vises of this type, no matter how well made or expensive, is that the geometry of the forces involved will always seek to take up any play by raising the moveable jaw. The can be controlled, as others say, by whacking with a dead blow hammer (so as to control rebound), tightening up bearing surfaces, or using aides, such as the round rod mentioned, or my favorite aide, the shaper hold down. The shaper hold down is a piece of bar with one curved edge and another almost knife edge. It is placed against the moveable jaw and the work. As the jaw rises, the holddown pivots about it's axis, thus pushing down on the work. They can be used singly or in pairs and are great for thin work held on parallels. See our web pages http://www.casco.net/~felice ------- Date: Tue, 29 May 2001 03:13:14 -0400 From: Stan Stocker Subject: Re: mini vise The screwless vise was reprinted in book two of Rudy's reprints. I scaled it up a tad for my mill drill, scaling it down wouldn't be much of a problem, although I'd stick with 5/8 or perhaps 1/2 inch thick stock as a minimum for the fixed jaw. The moving jaw would likely work out well if 3/4 inch square, using 1/2 inch drill rod for the two shafts. I suppose 10-24 would work for the screw, although I'd be inclined to use 1/4-28. Long 1/4 inch cap screws are hard to find in quantity one, a good hardware store may have them. My local good hardware store had long enough cap screws in stainless, the "normal" cap screws didn't come long enough. I used drill rod for both of the shafts, this saved me turning down CRS and allowed me to bore to a tighter tolerance. This isn't critical for accuracy, I just like a nice tool to have no rattling fits, even where they don't matter. I may be off base, but I think Rudy made his vise for a Sherline mill, so perhaps no modification would be required. Not having a benchtop mill, I can't comment on this with any certaintly. You can buy these small vises fairly inexpensively, but if you enjoy toolmaking, or have more time than money, you can certainly make a very accurate vise for little cost in material. If you have never done work to better than a thou (on purpose ;-) ), making such a vise will give you good practice at doing work in order for accuracy rather than for speed, in keeping track of reference surfaces, and in picking up edges. Good skills to aquire. My finished vise measures square to a tad under 2 tenths all over. Not having a surface grinder, some surfaces got lapped, filed, or scraped as needed. Jaw faces were lapped, then they were used as the reference surface for milling tongues and slots. The tops of the rails were filed, swept over on a surface plate, and scraped. Once flat to a tenth, I called it good enough! The total job took about 12 hours, a repeat could likely be done in about 6 hours. The vise was one of my learning projects, so I did some things out of order, made some dumb goofs, and did some things in harder ways than I had to. The usual learning sorts of mistakes. Making the base as perfectly square as you can, and getting the fixed jaw truly square to the base is worth the time. For many applications, you can clamp up the vise using a square on the table front edge and skip the indicating in step. Doing this on my mill gets the fixed jaw true to better than a thou per four inches. This assumes the mill table front is parallel to the table travel, something to verify in any event. You can also install a key to locate the table, as is often recommended. I don't like this as it interferes with clamping the vise at an angle, something I do fairly often. Having to stop and remove a key is just one more thing to do, parts to keep track of, and threaded holes to keep clean. Stan ------- From: "Bill Rutiser" Date: Thu Aug 2, 2001 9:42 pm Subject: Re: [sherline] Wide vise? Randy asked, >Related question--is there a technique for preventing the pull-down bar >from turning sideways in the slot? For some reason, every time I try to >adjust the vise that happens, and I have to poke and prod with wires, >nails, dental picks or whatever is handy at the time to try to realign >it with the slot. Is the center disk of your bar concentric with the ends? It appears to me from illustrations in the Sherline documents, that there is a newer style with the disk ecentric so that some it is always in the slot. One could make a new bar or buy one from Sherline. What I did, and it seems to work, is to cut two strips of Al from a soda can. These are about the width of the bar's center disk. They each have a hole at one end that goes over the bar ends. The strips are bent into an ell so that the short leg is parallel to the bar. The two stips overlap opposite the threaded hole in the disk. The bent end of the strips are notched to fit around the screw. Its a little fiddly to assemble but the bar goes into the vise body with the strips pointed up. The screw is installed thru the body, thru the notches in the strip, and then threaded into the disk. Even with the screw loosened so that the disk is touches table, the strips keep the bar aligned accross the slot. BTW-- Check the length of the allen head screw. Mine was long enough that it sometimes gouged the table. It needed shortening by one thread or so. Bill Rutiser Gaithersburg, MD ------- From: "Rich D." Date: Thu Aug 2, 2001 10:06 pm Subject: Re: [sherline] Wide vise? Randy, I use two vices side by side frequently, tho usually separated. There are all steel toolmakers vices similar to the Sh. that have a spring device that holds the screw up to help prevent the "nut" from rotating. See the Enco sale ad for model (flyer no)505-2144. Has clamp down slots on 4 sides, very smooth and all ground. Nice. RichD ------- From: "Marcus & Eva" Date: Thu Aug 2, 2001 11:01 pm Subject: Re: [sherline] Wide vise? Hi Randy: I'm not sure what your application is, but I run lots of setups with 2 vises side by side. Best way to set them up quickly is to clamp a single parallel with both vises ( make sure the parallel sticks up above the vise jaws a bit) and then clock in the parallel with an indicator in the spindle. If you are concerned about mismatch in the height of the vise beds, you have 3 choices: 1) take a whisker off the underside of the high vise until it matches the low vise. 2) Make a set of shim blocks for both vises (or a single sheet of shimstock if the mismatch is more than 0.005") 3) Make a set of soft sacrificial jaws that bolt onto each vise jaw and mill a step to nest your parts in. I wouldn't bother trying to make a single fixed or floating jaw for both vises. As far as your problem with the pull down bar, this is a weakness of that particular design. Best solution I have seen for it is to poke a bunch of cross holes into the vise base, and make a new nut by cross drilling and tapping a round rod. That way you can get at the nut from the side of the vise, even when the vise is bolted to a table. Cheers Marcus ------- From: "Craig Libuse" Date: Fri Aug 3, 2001 11:47 am Subject: Re: [sherline] Wide vise? Randy, I haven't experienced the problems you mention, but perhaps your vise is not made properly. If you'd like to return it (To Attn: Luis) for inspection, we'd be glad to make sure it is right and return it to you at no charge (other than postage). As to matching an old vise with the new one, I suspect it could be done although the tension on each half might vary if the pull-down angle weren't exactly the same. I think the center dimension of each of the positions is the same, but with the diameters being different, the angle of the pull-down screw might be different. Even so, as I said, that might not make a difference in this application. Would one set of very beefy jaws on a single vise provide enough holding power for your application? Anyone else tried this? I'll be back August 20th. Craig Libuse Sherline Products ------- From: Randy Gordon-Gilmore Date: Sat Aug 4, 2001 10:30 pm Subject: Re: [sherline] Wide vise? Thanks for the suggestions, Bill. 8/2/01 Bill Rutiser wrote: >Is the center disk of your bar concentric with the ends? It appears Yes, it is. The vise is about 4 years old. >BTW-- Check the length of the allen head screw. Mine was long I use a couple of different screws with the vise, per Sherline's instruction sheet. I haven't had any problems with gouging the table yet--with the screw, at least! :-P Best regards, Randy ------- From: "Marcus & Eva" Date: Sun Aug 5, 2001 1:12 pm Subject: Re: [sherline] Wide vise? Hi Randy: Have you considered taking a whisker off BOTH vises? This would match their heights within the flatness tolerance of the mill. Alternatively, if you can bear to part with them for a bit, and you are willing to spend for the shipping, I could surface grind them for you. Only problem is that I'm up in Canada; you may have a bit of a hassle at the border. Cheers Marcus ------- Date: Tue, 21 Aug 2001 11:27:06 EDT From: WRSmith2x~xxaol.com Subject: Re: Newbie Question of the Day <> Hi Bruce: Here is a simple solution to your problem. Mount a 1/2" diameter brass rod in an aluminum disk and allow it to extend enough to be gripped in a 3-jaw chuck. Put this in the lathe, face it and turn to the desired diameter. Then, using a round nose tool of about 3/16" width, make plunge cuts into the face of the aluminum disk, leaving lands of about 1/4" between the plunge cuts. Clean the disk and the object to be turned with acetone. Apply super glue sparingly to the lands of the aluminum disk. Place the object to be turned against the super glue coated arbor and hold for about 10-seconds. Do the required machining and then heat the arbor with a torch to break the bond. Do not heat hot enough to form a gas. The object will not properly bond to you arbor without the plunge cuts. They allow room for the excess super glue and the required air to create the needed bond. When cool, wash with acetone to remove the residual super glue. TTYL W. R. (Bill) Smith ------- Date: Wed, 22 Aug 2001 10:17:53 -0500 From: "Bad Brad" Subject: Re: Newbie Question of the Day These are just suggestions. Any method used to end up with a finished product is the correct method. everybody has different views, experience and equipment. It's what you can do with what you have and maximizing even with major limitaions that will make a good machinist. One alternative is to use a piece of 1/2" bar stock, face one end off, add any detail to the part. Next, very carefully part off so that you end up with the 1/8" thickness, using proper speed and feed. A little cutting fluid will give you a nice finish. To do the hole circle a rotary table works best. But if one isn't available you can use a center dril and place a dimple in the center of the part just before parting off the piece. You can use this dimple for a ref. point for scribing a circle for locating the holes. Using some trig. the hole spacing can be calculated. Clamp the part and drill a way. FBA ------- Date: Wed, 22 Aug 2001 19:42:14 -0400 From: ron ginger Subject: Re: Newbie Question of the Day A casting is not likely to be glued well enough to machine. The glue arbors W.R. Smith uses are for very smooth and flat items like brass clock wheels. A cast aluminum head is not going to glue. You will need to fit it into the 3 or 4 jaw chuck very carefully, with just enough extended to make a clean facing off cut. The outside of the head should be left 'as cast'. Very light and careful cuts are needed. Many guys start their first model from a casting kit, but I suggest first building a few models from bar stock. Casting can be very hard to handle and setup. Bar stock is nice and uniform, can usually be clamped or chucked well, and if you scerw up its cheap to make a new part. It can ruin your whole day to ruin a casting! ron ginger ------- Date: Wed, 22 Aug 2001 20:53:20 -0400 From: Jim Ash Subject: Re: Re: Newbie Question of the Day I've got a few pounds of a bismuth alloy called Cerrobend. It's known to chemists as Wood's metal. It melts at 158 degrees F. It looks and feels a bit like lead. Take your part and put it face down in a small cylindrical cup. Heat the Cerrobend to melting and pour it in the cup. When it cools, it should have a nice grip on the piece, even thin stuff. Chuck up the Cerrobend with the part in it and machine what you need. When you're done, pour hot water on it and the part will release from the block. Save the Cerrobend for the next time. Be careful not to let the work get too hot during the machining steps, although it will sink some heat. This method works well for irregularly-shaped parts also. Cerrobend isn't cheap (maybe $20 / lb) but for Sherline-sized work, a pound should more than suffice for a long time. Jim Ash ------- Date: Thu, 23 Aug 2001 07:02:35 -0400 From: "Dick Blaney" Subject: Re: RE: Newbie Question of the Day Cerrobend [CERROSAFE] is available at Brownells, Inc. Try here: http://www.brownells.com/Index.html It's used by gunsmiths to make casts of rifle chambers. Dick ------- Date: Thu, 23 Aug 2001 16:49:56 -0000 From: n2562001x~xxyahoo.com Subject: Re: Newbie Question of the Day Bruce: Having built a fair number of models I think You will find Ron Ginger`s comment`s on target. If you do not wish to purchase Bismuth you can also use wax. I generally use a copper or steel pipe cap as a cup and then melt and pour in wax around the part. For most parts it will hold almost as well as bismuth and is a little easier to deal with. The copper and steel pipe caps can be put in the 3 or 4 jaw chuck. Jerry Kieffer ------- Date: Tue, 02 Oct 2001 11:36:25 -0400 From: Al Schoepp Subject: engraving I've got a Taig mill which I've just converted to cnc. I now find that I need to engrave some aluminum panels and I've got a question. I'm not sure if I'll be able to hold the thin panel absolutely flat so I think that using a v-tip cutter for the engraving any differences will be quite noticeable. Do the commercial engraving spindles have spring loaded cutters that will only penetrate the metal a given distance or do they have to make sure what they are cutting is absolutely flat? Does anyone have a drawing for a spring loaded engraving cutter holder that would work with the Taig? I'm not sure if I'm asking the right questions but would appreciate some advice. Al ------- Date: Tue, 02 Oct 2001 17:23:21 +0100 From: Tony Jeffree Subject: Re: engraving The commercial engraving machines certainly do use the kind of spring loaded holder that you describe - however, I haven't seen one made for/used in the Taig (though others may have?). I have done a bit of engraving on my Taig CNC mill (see http://groups.yahoo.com/group/taigtools/files/Tony%20Je ffree%27s%20Files/Engraving.jpg and http://groups.yahoo.com/group/taigtools/files/Tony%20Je ffree%27s%20Files/Final.jpg for the most complex example to date), and have tried a variety of techniques for holding thin metals. The one that has worked best for me is to hold the plate down onto some kind of baseboard (sometimes straight onto the mill table) with heavy duty double sided tape (carpet laying tape, for example), and for critical stuff, to skim the top few thou off the plate before engraving it so that the surface is nice & flat. The one thing you have to be careful of with this approach is that the cutting operations generate heat, which in turn softens the adhesive. I have also experimented with hot melt glue guns, and other adhesives - such as superglue - might be pressed into service too - however, the same warning applies! Heating the plate is, of course, the best way to remove it from the glue after machining. With brass/copper, a useful option can be to soft solder the plate onto a thicker backing plate, do the engraving, then melt the solder to remove it afterwards. This can be useful with sheet material that hasn't been annealed, as skimming the surface (or even just engraving a significant percentage of the surface) can result in the plate warping as it is engraved, and with sufficient force to break free of double sided tape or glue. If you're likely to do a lot of this kind of work, it might be worth investing in (or possibly making?) a small vacuum table. Regards, Tony ------- Date: Tue, 2 Oct 2001 09:23:33 -0700 From: "Nicholas Carter and Felice Luftschein" Subject: Re: engraving You might want to try making a vacuuum chuck, which will suck the work flat. This of course makes more work for you and needs a vacuum pump. The other option is double sided tape (never use oil coolant with that! Don't ask me how I know....) See our web pages http://www.cartertools.com/nfhome.html ------- Date: Tue, 2 Oct 2001 11:50:44 -0500 (CDT) From: Tom Benedict Subject: Re: engraving Tony, any ideas about making a spring-loaded engraving bit holder? After having dug a v-tip tool in a couple of times because of unflat-ness, I wouldn't mind spending a little time making a better mousetrap. Don't know about anyone else, but anywhere I go, I wind up looking at things and thinking to myself, "How did they make that?" or "How could I use that in my shop?" or "Now THAT's a neat trick!" The last time I was in a pet store, I stood there watching while some people got some tags made for their dog. (They must've thought I was nuts...) The way those machines grab the part is to put the part to be engraved inside a bezel, and press the part up from behind: ------- Part ------- \ | / Bezel \ | / +--- V ---+ | ---------------- | -------+ ---------------- +------- +--------------+ | | | Piston | The lip on the bezel is presumably flat and true, so once the part is pressed up against it, it's flat across the face, provided it's reasonably rigid (anodized aluminum should be) and reasonably flat (tags are only about 1" across, so you don't get much warpage on that scale. If I ever wind up making a large number of engraved parts about that size, I'd proably make a jig like this. 'Till then, superglue and double-sticky tape sound pretty good! One word of caution about using MDF as a backing: Unless you're working in an environmentally controlled area, MDF will warp. My shop is outside in a small shed, where temperatures vary wildly, and humidity can go from 90% down to 40% in twelve hours. Cut your MDF flat, mount the part, engrave it, and unmount it. Don't mount the part, leave it for a couple of days, and assume it's still flat. (Yeah, don't ask me how I know this.) Tom ------- Date: Sat, 17 Nov 2001 10:50:59 -0500 From: "Rich D." Subject: Re: Wide vise ? Daniel Munoz wrote: > Hi guys, > I have a problem and would like some advise from you. > I need to do repetitive cutting task on the mill, typically cutting a > groove in a small section (1/4" x 1/4") wood bar, or using a saw blade > to slice a large piece in thin (but long) stock. The problem I have is > to clamp it firmly, but easily and repetitively. > When I try to clamp it on the Sherline vise, it is obviously not wide > enough, the wood bar (about 5" long) bend when the extremities are > machined. I cannot see how to clamp it easily (well, easily for me at > least!) on the table mill, because the bar is thin and the clamps would > be on the way of the mill cutter. > > Is there some sort of wide vise design that exist, small enough not to > be on the way of the mill cutter or saw, but wide enough to secure a > long bar of flexible material for cutting ? > I could try to build something specific for that task, but I have no > idea what is the best design for this kind of problem. > > For now, I cut the groove for a small portion (a little larger than the > Sherline vise jaws) with some spacers under for the wood piece to be as > high as possible in the jaws while staying horizontal, then I slide > manually the wood piece and continue the cutting on the new portion. But > it's a long task to do, and of course I loose accuracy between the > sections machined. Thanks for your advice. Daniel Daniel: I use as many as 3 vises clamped down side by side all perfectly lined up and squared. This allows long pieces or 3 seperate pieces to be held. The clamps between vises is a narrow 2 hole plate just wide enough to allow the 10-32 cap head screws to fit in. and sit on the vice grooves. RichD ------- Date: Sat, 09 Feb 2002 01:09:33 -0000 From: "iamstarvin" Subject: Re: Mounting items to a faceplate -- In sherlinex~xxy..., "Kevin P. Martin" wrote: > Having tried the super-glue trick once and failed, I'm 0 for 1 on the > "gluing workpieces" technique. > Even for thicker-walled items, crushing is not the only problem: the > three- (or four-) lobed out-of-round caused by the jaw pressure will > become duplicated in reverse when you do more turning, that is, the > finished part will have high spots on the o.d. > lined up with where the jaws were squeezing the walls in. > You might consider turning the I.D. first, then making a close-fitting > plug that gives the jaws a backing to tighten against. The closer > the fit (provided you can insert and > remove it easily enough!) the better this will work.-Kevin Kevin: I have used super glue many times, I have a sherline mill and a Logan lathe I make fly fishing reels and the first time I used super glue I pushed it hard making .035" boring cuts (removing .070"/pass) I have turned, faced and bored and never have had a failure. The secret seems to be that you need to cut grooves for the glue. I cut .020- .025" wide grooves maybe .020-.030" deep. When i'm finished, a rap with a fiber mallet and the work pops off. Don't give up it has a lot of applications. If you use a 2" wide piece of stock with a morse taper beat in you can face the arbor off as needed. Great tool steve ------- Date: Sun, 17 Feb 2002 16:59:08 -0800 From: "Nicholas Carter and Felice Luftschein" Subject: Re: T slot manufacture [taigtools group] >> I know I can machine a t-Slot from a block of stock (using a slot cutter, and then a disc cutter), but I don't have a mill yet, and I want to make the t slot for a milling setup on my lathe. Other than the risk of inaccuracies, and sheer hard work, is there any reason why I can't build up a T slot using strips of stock bolted together? Is the T slot stock a common extrusion you can buy? I was considering buying a spare compound to make my milling gidget, but I'll still need a T slot to mount to, and I figure most of my work will be in the orthogonal planes for the immediate future. If I can get my T slots sorted out I hope to build the milling attachment from scratch (including a vise, and some holddowns) and then progress to angles etc as required. One of these day I'll get a digital camera up and running so you can see the mess i make with/for my Taig.. It's so much a part of the family, all it needs is a name. Des << You can definitely build up a t-slot table, the book that Lindsay's offers on building your own mill, not the Gingery one, but the other author, does it with CRS. Basically it will be as accurate as the stock you use, so if you use ground stock it should be pretty good. There are also manufacturers of slotted aluminum extrusion, 80/20, Bosch that have some interesting uses. I find it from time to time at the scrap yard. Finally a call to Taig might net an unmachined end of their extrusion. See our web pages http://www.cartertools.com/nfhome.html ------- Date: Sun, 17 Feb 2002 20:21:31 -0500 From: "James D. Lawlor" Subject: T-slots or T-tracks Try a vendor that caters to woodworkers. Here in the U.S., several companies sell aluminum T-track stock. Typical dimensions are 3/4" wide by 3/8 " high, to take a 1/4-20 bolt. Woodworkers use the slots to hold clamps for drilling or routing stock. James Lawlor ------- Date: Fri, 14 Jun 2002 20:50:58 +0200 From: Douglas Burkett Subject: Re: Enco Vise with Sherline Mill >> I've noticed that Enco is offering a "fine quality" precision screwless vise for $39.99 The Jaw is 2 x 1 with an opening of 2 1/2 inches. Overall length is 5 1/2 inches. Is anyone using this vise with a Sherline mill? If so, what are your experiences with it? How decent is "fine quality" in the context of this vise? Thanks, Carol & Jerry Jankura Strongsville, Ohio << I just received the av428-9010 4"TOOLMAKER VISE SCREWLESS 7"OAL $49.99 in the mail, and if the one on sale is like this one it is certainly worth it. The one I have is a substantial vise compared to the one Sherline sells. Of course that comes with the problem of the vise taking up quite a bit of room. The vise has no finish where the Sherline does. So I suspect that you will need to pay more attention to proper care. I clamped it down and ran an indicator across the fixed jaw, both the top and face. Less than a thousandth of change across the entire jaw. Which is less than the tolerance of the setup. I'm happy with the one I received. Doug -------- Date: Sat, 15 Jun 2002 20:54:54 -0400 From: "Marshall Pharoah" Subject: RE: Enco Vise with Sherline Mill If this is the smallest of the three or four sizes they have, then I have one. The quality is quite good. Problems I found are: Be careful that the angle of the screw does not get too steep, or you will scar the table of the mill. This is one reason why I made a plate to hold mine, the other reason is the plate has a lip, so the vise goes on almost perfectly square each time. There is more material on the fixed jaw of the vise than on the Sherline. I continually end up inserting and removing the riser block to compensate for this. For this reason only, I don't recommend it for the Sherline mill. If you don't mind mounting it traverse, then it's fine. Marshall ------- Date: Fri, 14 Jun 2002 13:00:26 -0700 From: Wm. Dubin Subject: Re: sherline vise Yasmiin, Actually, I recently read (in an English model eng. magazine) about using two vices' at once, and, as I mill long pieces A LOT it seemed like an interesting thing to try, so I ordered a 2nd vice from Sherline. The way I set it up, was with one vice mounted so that its left hand corner was at the edge of the mill's X axis, which allowed me to do work right up to the edge of the vice. The second vice was set parallel to it, but in from the right hand edge by about 1.5 inches. Set this way, a 6" long parallel could be placed in both vices's at the same time, which made setting them at 90 degree's to the bed, and 100% parallel to each other very easy (using a DTI ). When I put stock across both vices's, I use parallels UNDER the stock... that way I relate to the bed and not the vices's height. So far, this system has proven out very well, its far easier to set up than a single vice, and if necessary, the right hand vice can be removed, leaving most of the bed free for another set-up, and re-aligning this vice on re-instillation is very easy, as the left hand vice gives you instant location. I highly recommed this set up... only wish I had known about it long ago. Wm. ------- Date: Tue, 09 Jul 2002 22:48:07 -0000 From: "keithbaddock" Subject: Re: Another clamp question --- In sherlinex~xxy..., "Al Lenz" wrote: > Was cutting a set of wing ribs out of 1/8 balsa sheet and using > double sided tape to hold down the stock, (along with a couple of > holes and alignment pins). Works OK, but does take some time to > peel up the tape when it loses it's 'sticky'. Thought about making > some spring clamps maybe out of wooden clothespins or such. > How do you guys do it? thanks al Drill two holes through each rib and use 10-32 stud, t-nut at nut to clamp it down. If 10-32 too big, use 4-40 allthread and make some custom t-nuts to suit. Typical way of holding them for sanding too, but normally with a plywood template on each side of the balsa stock. Don't forget the sacrifical piece at the bottom so you don't cut into the table! Keith ------- Date: Tue, 05 Nov 2002 12:22:55 -0500 From: Stan Stocker Subject: Re: 5C SPIN INDEX FIXTURE atlas101a wrote: >>> Just bought a 5C spin index fixture on eBay. It holds 5C collets and can be indexed. It was not very expensive and it looks like it might be used for gear cutting. Anybody experience with such an attachment? I know it is really meant for grinding operations and not milling. Anybody? If it is really a bad idea it has to be degraded to a conversation piece. Piet Jan <<< Hi Piet: I use one all the time on the mill. You can position a shaft to any whole degree easily. I use mine to mill flats, hexes, make reamers, just about anything that I do to a round bit of shaft (up to 1 1/16 inch) in the mill. These are very useful little gadgets :-) 5C collets are also available in hex and square style if you happen to need such things, they are a bit more expensive, but can be handy. You can cut gears with them as well, although only ones that can be indexed by whole degrees. If you have a lot of gear cutting to do, a dividing head may be a better choice, or a shop made indexer that can take plates you drill with the appropriate number of holes as is often done by clockmakers. Cheers, Stan ------- Date: Sun, 24 Nov 2002 10:24:36 -0800 From: Wm. Dubin Subject: Re: Why Parallels - was (Newbie) What accessories for starters with a mill? Ned: Parallels do several things, amongst them, raising the work above the table. The reason I use two large ones when using both vises, is because the inside bottom area of the vise was never meant to be exactly parallel to the milling table. It does a good job of this, but depending on the amount of accuracy you require, if you raise the stock above this, then when you clamp your vise on the stock, it will be as parallel to your milling table as possible. "Good" means the best... best, 99% of the time, means the most expensive (Starrett). Yes, you can get along just fine with Harbor Freight, but when the time comes to be "spot on", spend the money for the very best. That way you can screw up and be only half off... screw up with the cheapies and you'll be VERY off. It all depends on what you (and your work) require. As to how useful are parallels, well, I use them at least 85% of the time I am on the mill. The only one's I've not gotten full use from are a set of "wavy" parallel's.... Add to this list, a "good" set of 1-2-3 blocks... HTH. Wm. ------- Date: Fri, 27 Dec 2002 11:29:24 -0500 From: "Ned Carey" Subject: flycutting flat brass stock I am making a small fixture using K&S 1/6 thick by 2" wide flat brass. The brass isn't exactly flat, it has a slight bow to it. I've thought about flycutting it. My concern is two fold. First since this is already thin, might flycutting add to the warpage by releasing stresses in the material? Secondly, How do I hold it? Since the clamps hold the stock from the top they will get in the way of the flycutter. Can I clamp it to the mill table and move the clamps around as I flycut different parts of the sheet. I just got my mill and love it. I have yet to use the flycutter. Thanks, Ned ------- Date: Fri, 27 Dec 2002 09:00:30 -0800 From: Wm. Dubin Subject: Re: flycutting flat brass stock Ned: Forget the mill, heat the metal gently, and wearing gloves bend it back by hand. Wm. ------- Date: Fri, 27 Dec 2002 09:35:01 -0800 From: "Orrin B. Iseminger" Subject: Re: flycutting flat brass stock I'll go along with Wm. Dubin's answer to your problem. That said, if you ever need to machine thin stock in the future, there are at least two ways you can do it: 1.) Use 3M double-stick adhesive tape (the thin stuff, not the foam variety) to hold your workpiece flat. When done machining, release it by heating with a heat gun or hair dryer. Be careful if you use a heat gun. They get *very* hot and can cause damage. I use it frequently and it has never let me down. 2.) Use "instant" type glue (crazy glue). I've never tried it, but WR Smith, a well-known clockmaker, recommends it. He uses heat to release it, afterwards. Smith uses a fixture to hold the part being machined. In order to supply the air that the glue needs for curing, he machines shallow grooves in the fixture every 3/16" or so. Orrin Orrin B. Iseminger Colton, Washington, USA http://users.moscow.com/oiseming/lc_ant_p/index.htm ------- Date: Mon, 30 Dec 2002 04:16:33 -0000 From: "timgoldstein " Subject: Re: Securing a piece to be milled Double sided tape can work great if you have enough surface area and the part does not get hot (should not be a problem with heat on the fiberglass). You also want to aviod cutting into the tape as it will gum up the cutter. You can also use screws around the outside edge of the part into the sacraficial piece. You just have to be careful to use enough to not distort the piece. I have used a combination of both methods many times. Be warned that machining fiberglass will ruin your cutter very fast unless you are using carbide. Even then the bit will wear very quickly compared to cutting aluminum. Tim [Denver CO] ------- Date: Mon, 30 Dec 2002 22:04:17 -0000 From: "Ted Walls" Subject: Re: flycutting flat brass stock If you use 3M double sided tape you can release the brass by soaking in a little kerosene or paraffin. ------- Date: Mon, 30 Dec 2002 15:58:45 -0800 From: "Orrin B. Iseminger" Subject: Re: flycutting flat brass stock That was what I used the first time I used double-stick tape for holding thin sheets of brass. After soaking it--completely submerged--in kerosene for a day, the sheets were still stuck. It seems to take a very long time for kerosene to soak across half the width of tape. I finally gave up on the kerosene and used a hot air gun. I had the brass unstuck in a matter of minutes. You can see the result at: http://users.moscow.com/oiseming/lc_ant_p/pic_Prj1.htm Construction of the blade guard is still underway. Regards, Orrin ------- Date: Sun, 16 Feb 2003 08:34:22 +0000 From: Steve Blackmore Subject: Re: Small Vises [TAIG GROUP] >Hi all, I'm looking for a decent small vise for holding 1 or 2 >inch long, 1 mm to 2 mm thick material for engraving. Does anyone >know of a decent source? I'd like to fixture 4 on a plate for >multiple part engraving. The vise that came with the mill is >entertaining at best! I guess I'll be a needing small parallels >to go with them. If it's flat parts don't use a vice. Make/Buy an adjustable or fixed "grid" plate. Aluminium plate is best - see http://us.spillage.net/ but MDF will do fine. You can use Mitee-Bite type clamps or screws to hold down your stock. MDF (Medium Density Fibreboard) is great for jig plates - it will take a thread - if you want super accuracy skim the surface with a fly cutter then varnish with epoxy resin - you can then use coolant! There's a photo of an engraving job on my website that will explain what I mean. See http://www.pilotltd.net/taig.htm Steve Blackmore ------- Date: Sun, 16 Feb 2003 17:24:58 -0000 From: "whirlingdervish1950 " Subject: Re: Small Vises ~~~~>> My suggestion would be that small vise called "super glue" I use it for many different things.... one drop will hold your material until your done... multiple drops and accurate placement of multiple materials is no problem at all. Keep it Simple... After work is done, either a very slight prying or any product that disolves super glue will do to remove your engravings. Hope that Helps, Phil ------- Date: Thu, 20 Feb 2003 21:55:35 -0000 From: "notinsync10 " Subject: Can't figure it out..... Being about dozen T-nuts short of a competent machinist, I'm having a devil of a time devising a means to round out a disk roughly the size of a nickle without first mounting it on a center shaft. I can't start anew since the workpiece in question is pre-manufactured and would take a month of Sundays to reproduce. Does anyone know how this is done or if it can be done? TIA, J.B. Neiswander ------- Date: Thu, 20 Feb 2003 22:25:09 -0000 From: "n2562001 " Subject: Re: Can't figure it out..... J.B. If I understand this correctly you want the outside of the disk to be as round as possible. If so cut another disc the size you would like the first one to be. Then clamp the two together and touch up the first disk with a file using the second as a guide. That is if there is no possible way to glue or mount it to a shaft. Jerry Kieffer -------- Date: Thu, 20 Feb 2003 17:33:55 -0600 From: Anthony Parisi Subject: Re: Can't figure it out..... Hi JB: I'd turn an aluminum rod to the diameter, then super glue the disk to the rod., being as sure as you can that the edge is aligned. Then take light cuts...turn the disk. (I wouldn't use accelerator as general wisdom is that accelerator weakens the joint.) A bit of heat from a torch or heat gun separates the joint. Cleaner gets rid of the old Ca glue. Ventilate when you're heating... Tony ------- Date: Thu, 20 Feb 2003 16:19:11 -0800 From: Alan Marconett KM6VV Subject: Re: Can't figure it out..... Hi JB, Center it on a rotary table, and clamp one side. Mill the edge you can access. Then add a second clamp, and remove the first. Mill the remainder. Trick is to keep it clamped while switching clamps. It might also be possible to glue it down with "super glue", and heat it up to release it. This assumes the glue is OK to use on the part. HTH Alan KM6VV ------- Date: Thu, 20 Feb 2003 20:22:30 -0500 From: "Bill Rutiser" Subject: Re: Can't figure it out..... Double sided carpet tape is sometimes helpful for this sort of thing. Also consider applying pressure to a small pad with a tailstock center. Take light cuts. ------- Date: Sat, 5 Apr 2003 22:29:16 EST From: tmwade4x~xxaol.com Subject: Re: Thread cutting I'm building an alignment plate to hold a cast iron angle plate. I'm going to drill through the plate, then thread it for 1/4" - 20 bolts, then cut the heads off the bolts. The bolts will be screwed in from the bottom, of course. I also plan to put in several holes in one end, each offset by about .002" from the next. My plate is a 4" x 10" x 1" block of CRS. A bit of overkill, but it was free. Tom Wade Hope, Indiana ------- Date: Fri, 11 Apr 2003 12:47:09 -0000 From: "Bill" Subject: Holding Cylinder on rotary head faceplate I need to hold some PVC pipe on the face plate of the rotary head on the Taig. The pipe will vary from 1.3" to 3" dia. and up to 3" long. Any suggestions? It is too big for the 3jaw chuck. Many thanks in advance. Bill ------- Date: Fri, 11 Apr 2003 13:31:58 -0400 From: Stan Stocker Subject: Re: Holding Cylinder on rotary head faceplate Hi Bill; Can you use the three jaw and cut the soft jaws to allow you to use it inner jaw style? You might get away with mounting some angles (as in the angles sold at the hardware store for joining wood at corners) to the table, then hold the tube to the angles with one or more hose clamps. Setting things up for concentricity could be a bit weird. You could also turn snug plugs for the tube, mount the plug to the table and press the tube down onto the plug. A bit of squeeze with a hose clamp might stiffen it a bit. Use long studs and a clamp bar across the tube to hold it down if you are not doing something that requires access to the entire end of the pipe. If you have LOTS of these to do, make expanding mandrels to mount on the table. Lots of work, but quick to use with minimal setup once you have them made. Make a special vise with V jaws out of some half inch plate or maple and mount that to the rotary table. Cheers, Stan ------- Date: Fri, 11 Apr 2003 13:26:36 -0700 From: Don Rogers Subject: Re: Holding Cylnder One thing to keep in mind is the distortion of the PVC when using a chuck. Stan's ideas of expanding mandrel or snug pugs sound like the best solution and would minimize any distortion of the PVC pipe. You might try making wood plugs and then saw them almost in half and use a couple short, large diameter wood screws as wedges to spread the plug for a tighter fit. Don ------- Date: Mon, 14 Apr 2003 13:01:50 -0000 From: "andrewyslee" Subject: holding part on CNC rotary table Like to ask what is the best way to hold parts on a CNC rotary table? Without a chuck, how does one hold parts on the rotary table. Would a 3-jaw or 4-jaw chuck be better? Leaving out metal parts, what can one make with a CNC rotary table? Thanks Andrew ------- Date: Mon, 14 Apr 2003 08:31:20 -0700 From: "Marcus & Eva" Subject: Re: holding part on CNC rotary table Hi Andrew: On a tiny rotary table like the Sherline the two best ways I've found are: #1) the 4 jaw chuck because you can fine adjust the axis of the part to coincide with the axis of the rotary table. #2) a magnetic chuck for bigger flat ferrous parts that are not very tall, and for mounting a grinding vise. The problem with the Sherline chuck is that its diameter is so small that there is not a lot of room for clamps around the job. On a large turntable (we had an 18" diameter one at the toolroom I used to work at), you've got tons of room for clamps and step blocks and vises...whatever you wanted to bolt on.) On the Sherline, you've got to resign yourself to making very compact clamps...mine are all "L" shaped, and made of a very hard grade of aluminum so they don't bash up the table. Even so, you're unlikely to be able to clamp anything more than a 3" square on the table. If you want to mount the Sherline vise, you will probably have to drill and tap some mounting holes in the turntable, and mill a slot across the fixed jaw end of the vise. Remember, with these tiny tools, you can't squeeze the stuffing out of the mounting screws without destroying something, so you need to substitute with more clamps...four for a vise is my preferred minimum, unless I intend to take only the lightest of cuts. Cheers Marcus ------- Date: Mon, 14 Apr 2003 10:57:09 -0700 From: Alan Marconett KM6VV Subject: Re: holding part on CNC rotary table Hi Andrew: The Sherline table has 'T' slots, so you can use 'T' nuts and the Sherline hold down set to secure your stock. I don't have a Sherline lathe (YET), but I bought both the 3 and 4 jaw Sherline chucks to hold work with in conjunction with the rotary table. Nice! Make ROUND things! HTH Alan KM6VV ------- Date: Mon, 14 Apr 2003 13:09:46 -0700 From: "Brown, Mark A (SPO)" Subject: RE: holding part on CNC rotary table Here's two ways I've accomplished this. If the item has a center hole at least 1/4" in diameter I use the following. I made a threaded piece that screws down into the center of the rotary table. The part that sticks up above the rotary table is turned down to 1/4" and sticks up about 1/8". This is center drilled and tapped. Then I put double sided tape on the rotary table. The piece is put on double sided tape then I thread a screw with a nut on it into the center piece. The nut is then turned down to tighten the work piece onto the tape. It holds VERY well.....sometimes too much as getting the part back off the table can be difficult. The second was to take a large piece of 1/4" aluminum plate and put countersunk holes in it so it can be mounted to the rotary table with the T-slots on the table and some countersunk screws. Then I drill and tap this as necessary to mount my work to it with clamps and such. ------- Date: Tue, 15 Apr 2003 07:53:35 -0500 From: "Nance, Tom" Subject: RE: holding part on CNC rotary table Hi Mark: I did sorta the same thing when I was making a flywheel. I made a threaded arbor for the rotary table and mounted the flywheel blank on the arbor and then chucked the arbor into the lathe to turn the flywheel. (There's a 3/8" shoulder above the arbor theads that sits down into the center hole of the rotory table that provided enough purchase to hold the arbor in the lathe without damaging the 3/8-26 threads.) The idea of doing it that way was so the flywheel would be absolutely concentric to the arbor. Well, the best laid plans... When the lathe work was finished, it was time to cut the spokes and so I screwed the arbor still holding the flywheel onto the rotary table. I then drilled a hole in the flywheel in an area between the future spokes and secured the wheel to the table with a screw, spacer, and a T-nut. I then used a DTI in the mill spindle to exactly center the table by registering on the outer rim of the wheel. Things were going swimmingly until I gave the rotary table a spin. Disaster. I figured I screwed up the centering process so I did it again. When I moved the DTI around the edge of the wheel, there was no deflection. However, when I rotated the table there was a good sized deflection. No matter what I did I could not center the wheel with the set up I had. In the end I mounted the arbor in the 4-jaw chuck on the table. It was a real circus trying to change end mills. I had hardly any room at all. What I figure went wrong (or rather, the thing I didn't count on) was the fact that while the flywheel was concentric to the arbor, the arbor was not concentric to the table. Either the center hole is not concentric to the table (not likely) or the threads I cut were not exactly concentric to the arbor (much more likely). I don't think I can cut threads with the precision required to use this method. Another difficulty is that after cutting the most exact threads known to mankind one has to unchuck the work and flip it around to thread the other end of the arbor. That introduces all kinds of errors. Well, in short, I'll never use that method again. I just wished they made a more compact 4-jaw chuck. The one I have eats up a lot of precious room under the mill head. Tom Nance Corpus Christi, TX ------- Date: Tue, 15 Apr 2003 15:13:00 -0000 From: "tnance0913" Subject: Mounting Stuff on the Rotary Table. Hey, Sherliners, Since my last post I've been thinking about how to mount work on the rotary table so that it is exactly centered on the table. The 4-jaw chuck is a good way to do it, but it eats up a lot of room. I might have another solution. How about a tool similar to the adjustable tailstock thingabob that Sherline sells. There are two parts to it. The lower part is a 1- 1/2 inch diameter disk that is, say, 1/8 inch thick on the end of a 3/8"D x 3/4"L shaft. The other end of the shaft is threaded with 3/8- 26 threads so that it screws into the center hole of the rotary table. There are two, 6-32 threaded holes in the disk for the screws that will hold the two parts together. The upper part of the tool is also a 1-1/2" diameter disk but it has a thickness of 1/4". It too has a center shaft, however its shaft is, say, 1/4" diameter and is threaded with 1/4-20 threads thru most of its length except for the last 1/8" or so. There are two oversize holes in upper disk for the screws that hold the tool together. They are oversized so the upper disk can be moved around on top of the lower disk. The holes are also counterbored so the screwheads are below the disk's surface and do not interfere with the work monted on the upper disk. To use the tool, you screw the lower disk into the center hole of the rotary table and then mount the upper disk on the lower but do not fully tighten the screws. Place a DTI in the mill spindle and register it to the edge of the upper disk. Don't turn the mill spindle, but instead crank the rotary table around and change the position the upper disk until you read no deflection on the DTI. At this point the shaft of the upper disk is exactly centered on the rotational axis of the rotary table. Now you can mount your work on the shaft and tighten it down with a 1/4-20 nut. The downside of all of this is that you have only a single choice of the center bore of your work - 1/4" in this case. I guess you could made a series of upper parts with different diameters of mounting shafts. But the main thing is that here is a way to mount work on the rotary table without sacrificing the space consumed by the 4-jaw chuck. What do you think? Tom Nance Corpus Christi, TX ------- Date: Tue, 15 Apr 2003 18:25:23 -0000 From: "Bruce Buchner" Subject: Re: Mounting Stuff on the Rotary Table. I was thinking of some kind of mechnism to turn the rotary table itself into a chuck. Imagine four jaws that would ride in the T-Slots and a piece that would fit in the center with four vertical slots that would align with the T-Slots. Lengths of threaded rod would have a groove on one end to fit in the vertical slots in the center piece and have the jaws threaded on them. Each jaw would then be independent so the part could be perfectly centered to the table. It would also reduce the height which is very important when using the table. It should be possible to make jaws of different heights. I would think that each jaw should have a shoulder to ride on the surface of the table for stability. I am not enough of an engineer to make this but I'm sure one of you guys could make this work. If you do please make me one too. Bruce Buchner ------- Date: Mon, 16 Jun 2003 09:17:54 -0400 From: Ken Jenkins Subject: Re: Slick little vise arrangement. [TAIGTOOLS GROUP] Came across this vise which looks very simple to construct and very useful especially for engraving signs. http://npmccabe.tripod.com/minivise.htm ------- NOTE TO FILE: Workholding on a Sherline mill has crept heavily into the discussion of otherwise Sherline specific issues. For example, some workholding discussion with general ideas can be read in the text file Sherline Mill Quirks or Tips -- see a thread called "Z Axis rotation" (in 2003). Again, that just goes to prove that you should browse more than one file if looking for specific topics. For any mill topics, it helps to scan the Sherline and Taig mill files as well as the more general files like Milling Tips or Workshop Tips. ------- Date: Sat, 6 Sep 2003 08:28:47 -0700 From: "P. J. Hicks" Subject: Hold downs and tooling plate [SHERLINE GROUP POSTING] I made a nice tooling plate from 3.5" x 1/2" aluminum flat bar. Drilled 4 rows of staggered holes, tapped 10-32, and flycut for flatness. Works great. For hold downs I made a set of clamp bars from 3/16" x 1" steel flat stock, tapered the business end, drilled and tapped 1/4-20 hole at the other end and slotted down the centerline longitudinally. In use I use 10-32 setscrews of various lengths as a pivot tightening post, I use various lengths of 1/4"-20 round head carriage bolts head down on the tooling plate where the step block might go. The carriage bolt is easily adjusted by fingers for correct height and the 10-32 nut and setscrew in the slot tightens the whole thing down. The setscrews are also installed finger tight. Three or four can be installed in the time it takes to read this! PJH ------- Date: Thu, 9 Oct 2003 11:24:41 -0700 From: "Brown, Mark A (SPO)" Subject: RE: Securing work to the rotary table From: Lee Owens [mailto:longdistanceoperatorx~xxyahoo.com] >>How do you do it if you don't have holes in the part? I'm making my first project on my new machine tools and ran into this problem last night. The project is a 1/8 scale model of a Ferrari V-12 and I was working on the block last night. I drilled holes in it but what if I want to make something like dice? BTW I ran into clearance problems several times last night. The Tilting Angle Table w/Rotary Table kept running into the vertical arm. I ended up turning the whole setup around and using a mirror to turn the table 180deg and lock it down.<< Sometimes I design stuff with holes in it that look decorative or are filled with ornamental plugs when the actual purpose of the hole was for hold downs. If you look at the Stirling I designed and built (the black and gold one) at www.zora-arkus.com you will find quite a bit of this. Another technique I use if the part is big enough is a holding plate of sorts. I made a piece that screws into the rotary table much like the threaded plug that holds the 3 or four jaw chuck to it (btw, using the 3 or 4 jaw is another method). However, this piece is drilled and tapped in the center and doesn't stick up higher than the rotary table top. Then I drill a hole through a blank, put double sided tape on the back of the blank and put it on the rotary table with the hole centered over the plug I built. Now you put a bolt through the blank into the threaded plug and tighten it down. Believe me, it's pretty secure (sometime takes chemicals to release the tape). Now you can drill mounting threaded holes where ever you want in the blank to hold larger or odd shapes. Mark A. Brown ------- Date: Thu, 9 Oct 2003 11:46:23 -0700 From: "Dave Hylands" Subject: RE: Securing work to the rotary table You can also use crazy glue (or other cyanoacrylate glues) to secure your work to a piece of metal which can be clamped. Apparently you can use heat to break the glue joint (I haven't tried this). There are also metals which melt in boiling water that can be used for fixturing: http://www.use-enco.com/CGI/INPDFF?PMPAGE=699 Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ ------- Date: Thu, 9 Oct 2003 20:23:00 +0100 From: "Mark Howard" Subject: RE: Securing work to the rotary table These glues work well for some things and the joint can be broken by applied heat, BUT, beware of the fumes given off (I'm led to believe that cyanoacrylate contains cyanide - the name kind of gives it away!). Only apply heat in a very well ventilated area, preferably outside with a stiff breeze blowing! I don't even know if this is recommended - although I've done it several times and managed to stay vertical! Regards Mark Howard ------- Date: Fri, 10 Oct 2003 13:33:39 -0400 From: "John Thompson" Subject: superglues Just for the record, superglues (CA glue) do NOT contain cyanide. You can use acetone to soften and remove CA glues, or sometimes a sharp rap with a deadblow will remove the part if they are both metal. Some people develop allergies to CA glues, so its best to use a fan or other ventilation when using these glues. Basically just keep your head out of the fumes. John ------- Date: Wed, 15 Oct 2003 09:35:43 -0700 From: Don Rogers Subject: Re: Out of the Box >Parallels - These can be used to set something up higher in a vise, >among other things. They're very very good to have. I just picked up a set of parallels for my Taig. I bought sets of high speed steel tool bits in every size from 1/8" through 5/8" They are not ground to size, but they are ground parallel. The cost for the smaller ones are almost nothing, $0.39 each in lots of 10. Even the 5/8" were less than $4.00 each. The lengths run from about 2.5" to near 4". Just right for the small vises. The shortest set of parallels I could find was 6". Don ------- Date: Wed, 15 Oct 2003 14:22:48 -0700 From: "Dave Hylands" Subject: RE: Re: Out of the Box Sherline makes a little set: http://www.sherline.com/7505pg.htm Little Machine Shop also sells a set that's only 3" long: http://www.littlemachineshop.com/products/product_view.php?ProductID=1893 Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ ------- Date: Wed, 15 Oct 2003 20:20:11 -0000 From: "Jim Knighton" Subject: Re: Mill vise just a little bit bigger than factory Sherline? This might not be what you're looking for, but I have a 2" screwless vise that I got from the Little Machine Shop. Like the Sherline it is abt 2" wide and 2" tall. I have both vises in front of me as I write this. The Sherline's jaws measure approx 7/8" deep, the screwless is 1". The Sherline opens to a max of abt 1 7/8" (with liners in place). The screwless doesn't have removable liners and it opens to abt 2 5/8". OAL of the Sherline is abt 4". OAL of the abt 5 1/4". The Sherline is aluminum with a few steel parts. The screwless is all steel, much more robust in construction and substantially heavier (abt 3-4 lbs). It's an all-around nice vice. I don't recall the price, but it was well under $50. Screwless vises are available from a variety of sources. LMS pricing is in the middle of the range. I've seen 1" and 1.5" models, I purchased the 2", and I've looked at 3" and 4" models. The 2" is a nice "upgrade" from the Sherline product with slightly larger work holding capabilities. The 3" from LMS is a nice vise as well and might be closer in size to what you are looking for. Check weight and dimensions before purchasing. From my own research I concluded the 3" would be a bit large for the Sherline mill, but would work nicely with my mill/drill. I haven't purchased it as yet, however. Another alternative might be the Taig milling vise. It looks more like a drill press vise and compared to the screwless and the Sherline vises it looks a tad wimpy. Looks are deceiving, however, and this is actually a nice, albeit small vise. I am using one for one of my projects. It opens a bit wider than the Sherline but not as wide as the screwless. It is also relatively inexpensive at abt $28-29. Your best alternative might be to take a close look at the Taig vise and then build your own to roughly the same pattern. Regards, Jim Knighton ------- Date: Thu, 23 Oct 2003 08:50:42 -1000 (HST) From: Tom Benedict Subject: Re: Holding irregular shaped items.... On Thu, 23 Oct 2003, scuffer52 wrote: > I was wondering what solutions have been found for holding > irregular shaped, flat backed items like a cameo pendant where you > want to engrave letters into the flat back? > Apart from holding the piece without damaging it the back has to > be square with the cutter or you will be cutting the letters at > different depths. Also the letters are not cut very deep and going > deeper with a V-tip(spade) cutter only makes the lines wider which > means the letters could run into each other. > I have thought of embedding the piece in plaster, wax etc. but > removing it without damage is a concern. Ideas?? Thx...Greg Miller I haven't used this, so I can't vouch for its effectiveness, but Rio Grande sells a fixturing compound that might work in this situation. It's a plastic putty that gets soft when it's hot and gets hard when it's cool. The "hot" temp is lower than boiling water, so it's apparently pretty easy to use. The last Rio Grande Tools catalog had mention of the stuff on almost every page. "Look! It's a fixturing compound!" "Look! You can make custom tool handles out of it!" "Look! ..." Honestly it did seem pretty neat. My guess is you could make some sort of a backer plate that you'd bolt to your mill table. Put a blob of the stuff on top of the plate, squish the cameo into the blob, put parallels on either side of the blob (1/4" or 3/8" lathe toolbits?), and put a flat plate on top of that. Squish down, and the back of the cameo should be level with the tops of the two parallels. Let the fixturing compound set, mount to the mill, and go. When you're done, put it in some hot water and the fixturing compound should let go. Again, I haven't used the stuff. This is a guess. The jewelers on the list would have a much better idea how to go about doing this. Tom ------- Date: Thu, 23 Oct 2003 19:55:58 +0100 From: Steve Blackmore Subject: Re: Holding irregular shaped items.... Jewellers used to use Bitumen. (They still may do). It's allso used in repousse work where a pattern is punched from the back of the work. You can buy it in small blocks from any roofing supplier. Heating makes it soft enough to embed/remove item, white spirit will clean any residue. If your part can't stand heat, I don't know. Steve Blackmore ------- Date: Fri, 24 Oct 2003 15:35:11 -0600 From: "Tim Goldstein" Subject: RE: Holding irregular shaped items.... > but Rio Grande sells a fixturing compound that might work in > this situation. It's a plastic putty that gets soft when > it's hot and gets hard when it's cool. The "hot" temp is > lower than boiling water, so it's apparently pretty easy to use. Tom: The stuff is called Jett Set. We sell it in our store and I have used it a fair amount. The stuff works great and releases very clean. The easiest way to use it is to get a thermostatic hot pot (we also sell these and use it ourselves). Put tap water in the pot and plug it in. Put in a thermometer and adjust it to about 160 deg F (the hot pot has a temperature adjustment, but it is not calibrated). Once you set it never change the adjustment. Now put some of the Jett Set into the water. It initially comes as little pellets. Give it a few minutes to get up to temperature. Then just gather up the beads and squish it into a ball. It will be quite plastic at this point and warm enough you want to work fast. Squish it into a holder and then press in the piece you want to retain. Retention is mechanical so you have to surround the item completely on the sides. Now you can either let it cool naturally or if in a rush I throw it in the freezer for a few minutes. Once the material has cooled to room temperature it is quite hard. When you want to release the material you just throw it in the hot pot and it turns back into the plastic state and you just pull it off. As long as you don't overheat the stuff you can just keep reusing it. One pound of the stuff is about $35 and that is a lot of material. Tim A2Z Metalsmith Supply Inc 5151 S Federal Blvd Unit I-9 Littleton CO 80123 720 283-7200 www.A2ZMetalsmithSupply.com ------- Date: Thu, 13 Nov 2003 06:14:37 -1000 (HST) From: Tom Benedict Subject: Re: Stock mounting questions. On Wed, 12 Nov 2003, Aahz. wrote: > So I've made my first successful part on the mill, a small 2" > plastic gear that I eventually need to make out of aluminum. I > discovered I don't really know any reliable ways to mount metal on > the mill. Does anyone have some helpful suggestions for me? That's the question of the day, methinks... There are probably more ways to hold stuff on a mill table than there are ways to cut it once it's there. If you do a search on the terms "jig" and "fixture" you're bound to hit something. (Ok, granted 99% of it won't have anything to do with machining, but that's the way of the search engine.) One of the easiest and handiest is to have a vise. The one that came with my mill was not that well-suited for the task. I keep it in a drawer and use it as a small drill press vise, but it doesn't see much service otherwise. A nice screwless toolmaker's vise will set you back about $45 if bought new from Enco or MSC, and will save you lots of headaches. The second method, which I'm sure you'll run into as soon as you buy a toolmaker's vise, is clamps. The vise has no way for it to be mounted to the mill table, so you have to come up with some sort of clamping arrangement. The clamps I made for my vise were cut from 1"x1/8" steel angle that was drilled to take a #10-32 screw. The screw goes through the clamp, down into a T-slot, and engages a T-nut. Align the vise, crank down on the screws (gently... gently... it's an aluminum table after all), and you're good to go. I also made up a set of strap clamps along the same lines and basic geometry of the strap clamp sets you find in any Enco or MSC catalog. Only I've been too lazy to finish the job so mine have bare ends and no step blocks. At some point I need to go back and make step blocks and step the rear ends of the clamps. A nice set of strap clamps and step blocks are worth their weight in gold. (Ok, mine are made of aluminum so it's not THAT much gold.) For thin flat stuff my favorite is a sacrificial plate. Bolt the plate down to the mill table (I either clamp mine or drill it to take a #10-32 screw), and bolt the workpiece to the plate. Mill away to your heart's content. Remove the bolts and your part comes off. When the plate's too chewed up to work any more, fly cut it smooth and start over. More on the sacrificial plate: If you have a bunch of small thin parts you need to make, you can either silver solder or superglue your stock to the sacrificial plate, and cut it that way. If you use superglue, keep in mind that heat and some coolants will degrade the glue. So take light cuts and try the technique cutting something you don't care about just in case it comes loose during machining. To remove the items, heat them with a torch. Or remove the sacrificial plate and put it on top of a portable stove burner. (The fumes from superglue are really really nasty, so don't do this on your kitchen stove.) The first mention I've seen of this trick is James Nasmyth back in the 1800's. My guess is it's even older than that. Yet more on the sacrificial plate: A lot of bigger thin parts need cutting on the outside and cutting on the inside. If you're only making one or two of these parts, mill out the inside pockets and holes first. Then drill and tap some holes into the sacrificial plate so you can clamp the part through its own holes and pockets. Now mill out the outside shape of the part. I did a bad job of describing this, but it's a handy technique. That last use of a sacrificial plate would probably count as a rudimentary fixture, which leads to the next section: Fixtures! If you're making a bunch of stuff, it's often easier and quicker to spend a little time making a fixture to hold the parts. Fixtures are whatever you make that'll hold the parts while you machine them. Going back to the bit about thin parts that have holes in them, I made a bunch of parts at one point that looked like a truss. They were cut from 1/8" x 1" aluminum bar. I ran one toolpath to cut out all the holes in all the blanks while they were held in a vise. Next I made a fixture that had bosses to match the holes I'd just cut in all those parts. The parts slipped down over the bosses and could be screwed into place. Then I milled the outside of the parts. The real advantage to a fixture is that you align the fixture to the mill. Once. Swapping part to part you don't have to indicate anything in or use an edge finder to touch off any corners. It's neat. This is hardly an exhaustive list. Fixtures in particular deserve volumes. What it boils down to is this, though: Think of some way to hold what you're working on. That's how you can hold what you're working on. If it comes loose while you're machining it, think of some other way to hold what you're working on. Tom ------- Date: Fri, 14 Nov 2003 12:48:10 +0000 From: "steve sc" Subject: Fixturing... Great post on the mill fixturing! One other small technique that I have had luck with. Instead of superglue (cyanoarcylic?), I have been using a two part adhesive called typically "plastic welder". I buy it locally in an autoparts store. It is an acrylic, I believe but is very strong, and sticks to many materials. Other neat part is that it cures in under one-half hour to a good part of its final strength. Glues plastics, metals, woods. I have found that to unstick the parts after machining, soaking in the solvent used to clean plastic pipes prior to bonding will slowly swell and soften the glue...can take several hours. The glue seems pretty resistant to heat. It is very thick and definitely fills gaps. One thing that can be real trouble is double sticky tape. I once used it on a big mill and the heat generated soften the sticky and the piece slid and was ruined. OK to use on substrates that insulate the heat like wood or plastic, but not metal. ------- Date: Mon, 17 Nov 2003 14:10:55 -0800 From: "Scott A. Stephens" Subject: Re: Screwless vise >Anybody ever run into a screwless vise that will not go to the next >position when it is clamped to the table, due to lack of clearance >underneath? Is it safe to remove the little t-shaped retainer and >turn down its hub in the lathe? I found that if I pushed down on the allen head screw that pokes up that the little T thingy would go down enough so I didn't have to poke the pin out and try to push it back in threw those holes on the side. I would give that a try before you machine it down. I still have a bit of a problem moving to the next position, but this takes care of it. ------- Date: Mon, 17 Nov 2003 22:31:05 -0000 From: "John Bentley" Subject: Re: Screwless vise >I would give that a try before you machine it down. I still have a >bit of a problem moving to the next position, but this takes care of it. I tried that but there is just not quite enough space - I think I only need to remove a skim. I'm glad to hear I am not the only one who has had a problem. The cross bar on mine is held in position with a setscrew and not able to move when used as designed. Thanks, John ------- Date: Mon, 17 Nov 2003 23:05:14 +0000 From: Steve Blackmore Subject: Re: Screwless vise Mine did that John - just skimmed the retainer a little on the grinder, works great now. Sounds very much like the same make as mine, It came complete with fancy wooden box and was from J&L. Just a skim was enough to make it work as designed. It's surprisingly square and true and the surface is very hard, accidentally tried to mill mine, no damage to the vice apart from to the finish, but the mill was a "bin job" - totally blunt ;) Steve Blackmore ------- Date: Thu, 11 Dec 2003 11:53:09 -1000 (HST) From: Tom Benedict Subject: Fixturing Question Haaaalp! I've potentially run into a fixturing snafu that's got me scratching my head. There's still the off-chance someone else is going to make this part instead of me, but I'm all about hedging my bets. I need to make a part that has an outside profile similar to that of a con rod on a steam engine. It's about 0.100" long, 0.010" wide, 0.004" thick in the middle, and 0.008" thick at either end. I know it's likely to flex. That's ok, it looks like a con rod but it's being used as a strap. I'm planning on cutting it out of brass, but I'm open to options. The only way I can come up with to make this cut is to use CA glue to glue brass shim stock down to a sacrificial fixture. Brass can be cut dry, so I don't have to worry about coolant eroding the CA. I'm going to use aluminum as a fixture, so heat buildup shouldn't be a problem, either. This is going to require making a D-bit cutter about 0.010" or smaller, likely smaller. The fixturing alone is giving me fits. Making the eentsy- weentsy cutter is something I'm just not thinking about at the moment. Go ahead and point out that I'm in way way over my head. I am. But if you can come up with any better way to fixture the workpiece, or an alternative to the D-bit cutter, let me know. I'm definitely all ears on this one. Thanks, Tom ------- Date: Fri, 12 Dec 2003 00:31:43 -0500 From: Stan Stocker Subject: Re: Fixturing Question Hi Tom, Didn't know you had joined the watchmaking fraternity! Here's a couple of thoughts in addition to CA. Make the fixture from brass and solder the part down. Secure the part to the fixture with shellac or sealing wax. Releases at a lower temp, and shellac can be cleaned off with denatured alcohol. Make a birdsmouth (board with a V cut it in that clamps in a vise and use a jewelers saw for the outline. Make the part from three pieces of 0.004 shim, doubling up on the ends and soldering them. Or fold over the ends and solder, then saw to profile, bevel the transition from 8 to 4 thou with 600 grit. Might be easier to do the bevel on the ends before folding over or soldering on individual tabs. Anneal the brass first if you go the folding route, shim stock is left very hard from the rolling. Machine the part in a pocket, but in 1/4 inch thick stuff. Cut the perimeter around the part 1/8 inch deep. Fill the cavity with Cerrosafe, flip over, and flycut to final thickness. Drop in hot water to release. I have no idea if this would work for a part so thin, but one of the guys in our club makes critical pieces for laser mirror housings this way. If the thicker ends are for strength of attachment, maybe an old watch mainspring would be a source of better material? 0.1mm is a pretty common thickness, which is very,very close to 4 thou. You could then grind to width, as they are over 1 mm in width. Drill the holes by spinning a piece of 0.010 wire hard and fast against the watchspring to spot anneal the hole location, then drill (or EDM it). You could also just anneal the length of spring, machine, drill, then harden and temper if required. Pocket watch mainsprings are a bit thicker, the broken one I just measured is 0.007 thick, and 0.077 wide. Send me your address off group if you want and I'll send you a foot or so to play with. Make your 10 thou drill from music wire, or buy a pivot drill from Mascot (available from watchmakers supply houses). Mascot has flat and spiral pivot drills in this size, problem is most suppliers only sell them by the dozen (about $25/spade, $50 twist). Just imagine the fun of trying to use a spiral 0.010 drill in brass :-) Bet you don't even feel it grab and break! A high E string from a guitar is usually 0.009, might do the job, just grind to a spade point and relieve a bit behind the cutting tip. A local music store probably has an E string at 0.010 either individually or in a set. Drill by hand using a pin vise in any event. If you go this route, you'll have to chuck the drill with the tip very close to the pin vise. Mascot drills in this size have a flute around 0.060 to 0.070 long, then go up to a 1mm shank. Maybe you could reduce the tip OD of a #80 bit, they are 0.014. Never tried it, but I think rolling the drill towards you with a pin vice on a hard brass plate while pushing forward with a 400 or 600 grit sanding stick would make pretty quick work of it. Same method as used to hand polish clock and watch pivots. Finish off by flattening the cutting tips so the cutting edges have zero rake. Another possibility is a very fine needle ground to a spade point. I take it you have a magnifying headband and a double loupe already clipped to your reading glasses? :-) If you choose to buy drills, Timesavers sells Mascot drills individually for $3.25, or 3 for $9.00. URL for main site is: http:// www.timesavers.com The drills are on page 110 of the printed catalog that came in the mail recently, listed as pivot drills. They are on page 105 of the online catalog at the moment, not sure which one is out of date. The direct URL is: http://www.clock-keys.com/pdf/105.PDF Cheers, Stan ------- Date: Fri, 12 Dec 2003 00:24:45 -0500 From: "C. A. Weagle" Subject: Re: Fixturing Question Are there holes in the ends (like a stretched-out figure-8)? If so, you might be able to drill a randomly-placed through-hole for a small screw (if it's a strap, I assume you have tiny screws to fasten it down in it's desired application). You can zero off of wherever it ends up. If you clamp the other end of the (oversized) base stock to the tooling plate, you can locate and drill the other hole and screw it down too. The you're in the clear - _ might still put a drop of CA down in the middle to keep it from lifting. That's a pretty small part! I once had to make some Delrin parts on that scale in a full-sized manual milling machine. I was lucky that it had ballscrews, otherwise the backlash would have been larger that most of the dimensions! ------- Date: Sat, 13 Dec 2003 00:00:59 +0000 From: "steve sc" Subject: Fixturing... Tom, Re: the fixturing problem relating to making that little brass piece. Another option might be to make the piece out of brass using a chemical etch process like used in making PC boards. I *think* that brass is etchable using etchants such as ferric chloride (Radio Shack). What I was thinking (if I understand what you are trying to do) is to etch the piece out of brass shim stock and then thin the center section using some sort of abrasive process/filing. To make the resist pattern for the etchant, there are a couple of options. One is photochemical resist; the other that I use to make printed circuit boards is to print the positive on glossy paper on a LaserJet printer and then to iron the toner/resist onto the copper(or in this case brass). The clothes iron melts the toner and it re-fuses on the metal. Toss into the etchant and stir frequently. I guess you could even consider a two step etch process. First mask the ends, etch the middle to final thickness, then mask entire part, etch to finish. If you are interested, search the web on PC board iron laserjet resist. You should find a couple of how-tos. Steve ------- Date: Sat, 13 Dec 2003 00:34:19 +0000 From: "steve sc" Subject: Etching parts... Tom, Shortly after posting, my enthusiam is somewhat curbed about etching. The potential issue is undercutting. With a width of 0.01 and a thickness of 0.008, you are looking at a pretty high aspect ratio. That being said, I think it may be worth a try...might require tuning the geometry some and maybe playing around with the etchant concentration and/or agitation profiles. I *think* undercutting is a function of how well the etching byproducts are flushed out. Anyone out there with chemical machining experience? All I have done is PC boards. Steve ------- Date: Sat, 13 Dec 2003 05:47:22 -0000 From: "Terence T.S. Tam" Subject: Photoetching (was Re: Fixturing...) My shop teacher has a locomotive that he's been building, and tags on the locomotive were photoetched magnesium. Solid plate of aluminum went in, I guess they applied photo resist on, developed it, etched it. It looks like a cast iron plate (with his name and year the locomotive was built on it), but of course in miniature. Brass *definately* can be photo-etched. Model builders have been using photo-etched parts for years to detail model, when injection molding won't give you the level of details required. Brass is I think 60+% Cu, and ferric chloride will etch it (get this from Radio Shack as PCB Etchant). Just make sure you don't have copper pipes before pouring it down the drain :-) http://www.dynaart.com/ - these guys sell toner transfer paper - and it's good stuff. Just a happy customer. One funny note: When I first started this with etching PCBs I polished the hell out of the copper clad. Like, mirror shiny. The toner wouldn't grab on because it was polished so fine, so I called up the owner and he said, "Oh, just scour it with a scotch brite". I made PCB with SMT pads with it okay after that. Here's a link on photoetching brass. http://home.att.net/~ShipModelFAQ/ShopNotes/smf-SN-PhotoEtch.html Terence ------- Date: Sat, 13 Dec 2003 08:41:42 +0000 From: Tony Jeffree Subject: Re: Fixturing... Naturally, you would need to (accurately) position the resist on both sides. Regards, Tony ------- Date: Sat, 13 Dec 2003 20:22:35 -0000 From: "vks_generic" Subject: Re: Fixturing... > To make the resist pattern for the etchant, there are a couple of > options. One is photochemical resist; the other that I use to make > printed circuit boards is to print the positive on glossy > paper on a LaserJet printer and then to iron the toner/resist on Both work great for removing very small amount of material. I have already forgotten, how deep you need to etch, but if it is anything significantly deeper than the thickness of the conductive layer on a PCB board, you may have some problems. 1. both methods do not produce a 100% inpenetrable coating. The etchant still gets into the masked parts, just not as much, and is not agitated, hence it doesn't etch as much. The longer you etch your piece (to remove more material), the more of a problem that would be. A great replacement for the laserjet method is fingernail polish/laquer thing - whichever way you spell that. It is also easily removed with acetone. 2. When etching deeper than PCB-thickness, the etchant will eat under the masking coating, creating something that looks like a miniature overhanging cliff. The solution to that is to etch in several steps, recoating the masked area with fingernail polish or something between steps. Also, this way you can easily get a fairly precise gradual thickness change - just coat a little more or a little less area each time. Vlad ------- Date: Sun, 28 Dec 2003 19:10:45 +0000 From: Clive Foster Subject: Re: Clamp Kits [was taigtools group but applies to sherlines too] I'm inclined to be a bit wary of conventional T nuts & studs on our lightweight tables. I prefer short T studs with a tapped hexagon 'long-nut" holding it in place with whatever length of stud suits the job screwed into it. With a washer under the long-nut the the t-stud assembly can be clamped firmly to the table so virtually eliminating the risk of distorting slot or table. I have seen tables distorted or with bits torn out of the slots on larger machines by people being stupidly careless and ours are probably light enough for a moments inattention to get you into trouble. Use a bolt or allen head with a conventional tapped through T nut and its awfully easy to go just a bit too far, forcing on the bed between slots rather than on the work clamp. I fabricate larger T nuts by brazing or gluing and pinning two pieces of strip together, the upper one sized to fit the the slot and the lower one sized to go under it, with the short stud brazed or locitited in as appropriate. For our size a strip long enough for 6 or 8 assembled by the loctite method should be very little trouble to make. HTH. Clive ------- Date: Tue, 27 Jan 2004 23:15:27 +0000 From: Tony Jeffree Subject: Re: Hold-Down clamps/blocks [taigtools group] >I've seen pictures of Sherline's clamp and block sets, but don't know >what the dimensions are. Are these a reasonable starting point? >Anyone know (or willing to take measurements of) the dimensions of >the sherline clamp and block sets? Alternatively, can someone >suggest reasonable dimensions for such items for use on a Taig mill? The Sherline hold down set works just fine with the Taig mill (I have the set & use it regularly). The only bit that doesn't work is the T-nuts, which are designed to fit the Sherline slots; you will need to make some up, but this is easily done by drilling/tapping UNF 10-32 holes in short pieces of 1/2" X 1/8" steel bar. You will find that many of the Sherline milling accessories can be similarly adapted. Regards, Tony ------- Date: Tue, 27 Jan 2004 15:34:48 -0800 From: "Dave Hylands" Subject: RE: Hold-Down clamps/blocks [taigtools group] Hi Jim, Basically, the slot in the middle needs to be big enough that whatever size bolt you use for holddown can move freely. The length can be quite variable. I've found several situations where the sherline holders were too big or too small, so having a variety of length is useful. Make the sides about the same thickness as the bolt clearance slot, and make the whole thing about two bolt slot thicknesses high (This is also quite forgiving, but longer ones should probably be thicker). So basically, there is no "right" hold-down clamp, other than the one that works for the task at hand. If you want the exact dimensions of the Sherline parts, goto this page: http://www.sherline.com/prices3.htm There's a section called 3D Part drawings, where you can download ACTIFY. Then for any part listed further down, where the part number has a bold red number, you can view the part in Actify and pull off dimensions. Parts 30130, 30134, and 30135 will be of interest to you. Sherline sells two different style of hold-down clamps: http://www.sherline.com/3012pg.htm http://www.sherline.com/3013pg.htm A coupe of others you might find interesting: http://www.sherline.com/tip3.htm http://www.sherline.com/tip5.htm Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com ------- Date: Wed, 28 Jan 2004 01:27:03 -0500 From: Stan Stocker Subject: Re: Hold-Down clamps/blocks sdw wrote: > I'm a beginner and i'm curious. What are you planning to use to > clamp down whatever material your going to be making into clamps > without clamps to hold it down in the first place? Hi sdw, Sorry, no stupid beginner question of the month award for you! Your question shows you're thinking. The question opens up a couple of areas beyond just how to hold stuff without having a complete shop. One of the "joys" of machining is figuring out how to do what you want with what you have. Usually it is a joy, sometimes it's a PITA, hence the quotes. Hobby and prototype machining is a lot like software development or any other complex but creative task. You usually get better results in less overall time if you stare out the window turning things over in your head for a while before starting the actual "work". Particularly true if there's some vagueness about how to go about the job at hand. I don't have a Taig mill, just the lathe. My mill is a bit larger, but the same approach works, you just scale up or down as you change machine size. IIRC, the mill also uses #10 hardware, so I'll go with that size. Quick and dirty starter strap clamping set up: Drill a hole sized to be a loose fit on a number 10 screw in the middle of 2 aluminum straps around 1 1/2 inches long, say 1/2 inch wide, and 1/4 inch thick. Then get some 10-24 or 10-32 square nuts at the local hardware store, along with several pairs of cap screws in assorted lengths, and a dozen or more #10 washers. Add some assorted bits of packing, say two pieces of keystock in 1/8, 3/16, 1/4, and 3/8 sizes. Might be cheaper to buy lengths of aluminum square stock than keystock, all depends on what you have handy and what you can get easily. Maybe some lengths of 10-24 or 10-32 allthread and matching hex nuts also, you can slice it up into the lengths you need. Just be sure all the hardware matches for thread pitch, and that you buy a couple of hex keys to fit the cap screws. One quick and dirty set of strap clamps all done. Not the ones you want to use forever, but good enough to clamp stuff to the table. Using strap clamps (or how to keep your mill table nice and your work held fast): Put the work up on 1/8 spacers (parallels if you want to use the correct terminology) so you don't cut into the table. If the work is 1/4 inch thick, use the 3/8 keystock under one end of the strap clamps, the work (on the 1/8 inch parallels) under the other. Strap clamps should be parallel with the table in use, not tilted up or down. Drop a long enough cap screw into the hole in the middle of each clamp, tightened into a square nut slid into the mill slots. If you can't line up the holes in your straps with the T slots, just drill another hole in the strap where you need it. Be sure the screw doesn't go though the nut and turn into a jack. If the cap screw threads in too far, use a shorter cap screw or add a few more washers between the head of the cap screw and the strap. More than one mill has had a tee slot cracked by ignoring this. Commercial T nuts are made with imperfect threads, meaning that the last 2 or so threads aren't fully cut. This keeps studs from becoming jacks. A good practice to follow when you make your good clamping kit. Don't go nuts tightening when using strap clamps, there is nothing on top of the table to help protect the T slots from being cracked or pulled through. Snug enough is good, heavy handed is bad. That's it for bootstrapping your way to strap clamps. The following is some general advice on making clamping goodies, along with some alternate approaches and comments on the why as much as the how of getting things done in the small shop. When making your step blocks, cut the steps in a long piece of stock, then cut into individual blocks. It takes a lot less time to make one long step block then slice it up than it does to make four short ones. Once you've made a few straps, go back and mill the slots in the 2 "make do" ones you started with. Nothing purchased for the starter clamps goes to waste. Make some real T nuts while you're at it. Use steel for these. Farm and Tractor supply houses sometimes have square stock that is a good starting point. The stuff sold as "weldable steel" at the local home center can be pretty nasty to work with. Buy good taps, and stop threading when a plug tap just starts to come through the bottom side of the T nut (imperfect threads are good for this application.) If you think about it, there are other ways to make your straps. You could use a long piece of 3/4 X 1/4 or 1/2 X 1/4 aluminum, and screw that to the table with some spacers (smaller fender washers would be a good bet here, they would span the T slots but be out of the cutting area) between the work and table. Put the screws through in between the ends of what will become the finished straps. Then you could mill the slots for four or more straps at once. Take the slotted strip off the mill, cut the clamps apart where the screws went through, finish up the ends with a file or belt sander. Remount the straps and mill the steps if you want to make your straps similar to the commercial ones. Don't forget to match the sizes of the steps on your step blocks - obvious once said, but the sort of detail it's easy to miss when starting out. If you have a bandsaw you could even use a rectangular piece of plate. Mill the steps along one side, mill the slots, then dice up the straps using the bandsaw. Could do this with a hacksaw too, if you have a high tension hacksaw frame, good blades, and like sawing. If you like making swarf I suppose you could even mill the straps apart, but this seems like a lot of time on a smaller machine. Always more than one way to get there, it's just a matter of what you have available. Get an industrial supply catalog (MSC, Enco, Travers, Rutland/Airgas) and spend some time absorbing the ideas behind all the neat goodies available to secure work. Many of these can be made very inexpensively, but cost quite a bit as they are specialty items. Just because the smallest commercially made "Clampitall XL MaxiUltimoso" gizmo is for full sized mills and costs $300 doesn't mean you can't make one sized for your machine from scrapyard bits and pieces. You need a decent vise with a mill, but it's amazing what you can do with some bits of metal, nuts, washers, allthread, and cap screws until you get one. The practice pays off down the road when you want to do something that doesn't fit in your normal workholding vises or setups. Sometimes you just can't afford the extra height of the vise. Doesn't matter if your mill weighs 60 pounds or 1200 pounds, there's always something that wants more table, daylight under the spindle, or rigidity. On the subject of vises, you can make a screwless vise using your mill without having a vise, provided you have an angle plate and a test indicator. A good project for the developing machinist, but not a good first project. Tom mentioned using screws and blocks of material to make a vise substitute in another posting. Works well, and such things are available commercially for larger mills. Sort of handy when you want to secure a long slab of material, while keeping the upper surface clear of hardware. I sometimes use such a setup when doing engine heads and other large items. You have to be careful of how hard you tighten things up, in effect you have a pair of levers trying to break out the T slots. Once again, tight is good, but this isn't a place to get in an upper body workout. When you work on the table surface, you usually have a more rigid setup, and you are working at the basic accuracy of the machine. When doing picky work I often work on the table, even if the work would fit one of my vises. Always nice to get rid of variables in the process. Maybe I just spent too many years doing test engineering to like stray variables. Just keep track of where the cutting tip is, it's hard to hide a spare slot on the mill table. My neighbor and I once cut a keyway in the crank of a Briggs and Stratton engine to take a different blade adapter without pulling the crank. Took a couple of angle plates, a precision level, and a sense of humor, but the job got done in a lot less time than it would have taken to tear the engine down. Not something you would do on a Taig or mini mill, but it shows that sometimes you just have to do "weird" things when it comes to fixturing. Old machine shop books have a lot of neat ideas from a time when shops didn't always have huge tool cribs. They are worth reading for the hobby shop machinist. Basic (mindset) rules of shop work: Know what are you going to do, and about how you intend to do it, before beginning. You just get used to making it up as you go. This doesn't contradict the item above, it simply accepts that not everything goes exactly as originally planned or expected. Blindly following a plan can be as bad as having no plan. Metal isn't very flexible, so you have to be :-) The more shop time you have, the less this comes into play for typical tasks. It always comes into play to some extent for the weird jobs. If it isn't going right, stop and figure it out. Pushing on when something is out of sorts is more likely to produce damaged tools, work, or machinist than astounding success. It isn't rare to have the setup time take far longer than the cutting. When doing oddball jobs the actual cutting is anti climactic, provided your setup is right... If not, it can be very exciting. Aim for dead on always. If you figure 10 thou is close enough, but you miss, it's scrap. If you aim for within a thou, and the part can be +/- 5 thou, you can slip up a bit and still have a good part. Good training for those jobs that really do have to be dead on. Cheers, Stan ------- Date: Tue, 27 Jan 2004 23:26:50 -0800 From: "Dave Hylands" Subject: RE: Re: Hold-Down clamps/blocks >One other question - what material should these be made of? Do I use >aluminum clamps for aluminum projects? Steel clamps all around? How >about the blocks (if I decide to go so far as attempting to make those?) Aluminum should be fine for a taig sized mill. Even if you want steel ones, I'd make a few out of aluminum to practice with. Use 6061 or 7075 aluminum, not the stuff you get at the hardware store. You'll probably want to make the T-Nuts out of steel (as per Nick's process), but even here you could make a few out of aluminum to start with. They'll just strip their threads much sooner :) Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ ------- Date: Wed, 28 Jan 2004 22:50:18 +0000 From: Clive Foster Subject: Re: Hold-Down clamps/blocks I'd be inclined to steer beginners clear of using aluminium for any purpose. Being so soft its a right pain for building up on cutters even if they are sharpened dead right with just the right feed rate, speed and lubricant. Hard enough for the experienced to get consistently right, highly dispiriting for a beginner especially if un-mentored. 'Tis a so and so to tap as well. Best use for pure aluminium is in small sheet scraps as clamp point protectors for work pieces. What you want is one of the light aluminium alloys of the sort usually collectively (and incorrectly) known as Dural on the UK side of the pond. Basically make sure you ask for a free machining alloy, the ones containing bismuth are relatively expensive but good for the beginners confidence as they machine easily to a good finish on any half decent approach to a good set up. Even Homer Simpson is in with a chance! "Dural" is a good choice for Tee nuts. Being softer its kinder to the table than steel and you will never strip the thread if you use them as Tee studs with a nut on top for the clamp, as I prefer, rather than Tee nuts with a bolt or allen head holding the clamp down. I always feel that plain Tee nuts are an open temptation to use the wrong length bolt when you haven't got the right length in stock or have robbed the workshop kit to repair the washing machine. It is important that both the ledges of the Tee nut which pull up against the table are at the same level. A canted nut puts horrible loads on the slot and having the bolt or stud anything other than perpendicular to the table is not good for clamping. Light alloy nuts have a bit more give than steel and so are more tolerant of small errors. Personally I'm too lazy to machine Tee nuts so I fabricate them by brazing two bits of suitably sized steel together, one thin to fit in the slots and one wide to go underneath, before drilling and tapping. This ensures that the pulling face is flat and at the same level on both sides. I'm also not the greatest fan of stepped packing block type clamps for anything other thing heavy duty jobs. I prefer a plain slotted clamp with a jacking screw. Either do the screw with a permanent foot to run on table or just de-thread the end and run it into a locating hole going about halfway through a load spreader plate 1/4 inch thick or so. Permanent feet are convenient but you end up making more clamps. Different length screws are easier to make as and when required so you soon build up a collection to suit your jobs. HTH. Clive ------- Date: Thu, 29 Jan 2004 08:17:43 -0800 From: James Eckman Subject: Re: Re: Hold-Down clamps/blocks > I'd be inclined to steer beginners clear of using aluminium for > any purpose ??? I guess I'm spoiled, I never get anything but good machining aluminum because it's offcuts from a local machine shop supply outfit. Build up can occur, especially if you are using steel tools on aluminum, I recommend always using cutters that have not been used on steel if you are using run of the mill cutters for this. I also use flycutters for finishing plate, the cutting angles I use can be used for hardwood as well, they are fairly radical and very sharp. I always use tapping fluid for Al so I've never had a problem with tapping. > Best use for pure aluminium is in small sheet scraps as clamp point > protectors for work pieces. I don't know if you can buy pure Al that easil