Ball turning has not had much discussion in the groups; consequently some additional help ideas have been added to the start of this file. BALL TURNING (a.k.a. RADIUS TURNING) is a turning operation that can be used to: 1 - put a smooth, rounded end onto a metal rod; or 2 - starting with a thicker rod, turn a ball on the end and thin the rest of the rod to suit the project; or 3 - turn a ball that is perfectly spherical (no rod left); or 4 - turn a concave curve into an object (make a depression). This subject that has been repeatedly featured in metalworking books and magazine articles. The latest (as I write this) Home Shop Machinist (HSM) magazine, November/December 2003, has the start of a 3-part article on making a fairly complex version for the third type (true sphere). This magazine can be bought from a news-stand or you can subscribe through Village Press, or you can find other articles through the publisher in back issues or consolidated books they publish. http://www.villagepress.com/homeshop/ The simplest way to put a ball on the end of a rod is to scrounge or buy a ball. If hardened, as in a ball bearing, it can be annealed before drilling an appropriately sized hole. John Bentley, in a message dated 30 Oct 2003, was talking about threading when the conversation turned to the ball handles he made. Here is a neat alternative to turning them from scratch. See the Threading text file on this site. (Sorry, but I don't have the space to repeat stuff in multiple files when the subject changes.) Or you could buy a commercial knob to screw/glue/solder/weld onto a rod. Or you could buy a commercial ball turning attachment suitable for your lathe. I see from an ad by OMW Metalcrafts that they have versions ready to go in two sizes. http://www.omwmetal.com/ (There are many other commercial units out there. Do a Web search.) If you look up some of the articles on making your own device, they range from simple to incredibly complex. It is interesting that one author in HSM's sister publication Machinist's Workshop in the April/May 2003 magazine wrote an article to prove you can do perfectly adequate ball/radius turning (types 1, 2, and 4) using standard lathe procedures and no special accessories. (See Village Press website above.) Author Guy Lautard wrote about a mathematical stepped approach to approximate a ball, followed by filing smooth, that will work with minimal equipment. See his books at http://www.lautard.com/ And then the horological approach (clock-making) is to turn the ball/radius freehand using a hand-held graver in an operation similar to woodturning. See http://horology.magnet.fsu.edu/wrsmith.htm And on both sides of the pond you can look through the excellent British magazines published by Highbury Nexus Special Interests Ltd for articles in their back issues -- see Model Engineers' Workshop. North American distributor is http://www.wiseowlmagazines.com/ And a web search or perusing the links off this site will likely find free advice and how-to articles, perhaps with pictures. 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 - 2007 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: Date: Fri Aug 25, 2000 12:25pm Subject: Radius cutter material. Would 6061 T6 aluminum be OK to make a radius cutter? What does Sherline use on their attachment? Thanks! Rogerio ---------------- From: Date: Fri Aug 25, 2000 1:53pm Subject: Re: Radius cutter material. On Aug 25, 4:25pm, videosx~xxm... wrote: } Would 6061 T6 aluminum be OK to make a radius cutter? What does } Sherline use on their attachment? Thanks! Rogerio When I made a clone of the Sherline radius attachment, I used cast aluminum jig plate, because I had some on hand. 6061 should work as well. I don't think it's really critical. Picture available at: http://blw53.freeyellow.com/radiustool.jpg Although in the picture it looks like it's spilling off the cross slide, it actually just fits within the length. This was the first thing I made when I got the milling column for my lathe. The first thing I made with the radius cutter was the brass ball for its own handle. -Brian -------------------------- From: Date: Fri Aug 25, 2000 9:05pm Subject: Re: Re: Radius cutter material. On Aug 25, 8:49pm, "John D. Guenther" wrote: } Brian, Nice job, looks like a fairly easy project. What thickness was the } material for the H part? The rest I can figure out based on center I used 1 inch thick jig plate - minus a couple thou practicing with the flycutter. } height. I will be making for another lathe. } Thanks for sharing your project with us, it is really neat! John Guenther -Brian --------------------------------- From: Ron Ginger Date: Mon Aug 28, 2000 3:45pm Subject: Re: Bride of radius cutter I think Joe Martin comments in the Tabletop Machining book that he tooks a different approach in his radius cutter. The more common approach is to have the cutter axis vertical, mounted on the lathe slide. With that you can make a radius with its center off the axis of the lathe. There is a guy that sells a conventioanl radius tool for the Sherline, at about the same price as the Sherline version. I dont recall the name now, but he has been mentioned here, and shows his tools at NAMES and probably PRIME. I think the Sherline web site has a pointer to him. I think its a more flexible tool than the Sherline version. ron -------------- From: Date: Tue Sep 12, 2000 00:46am Subject: Radius cutter finished. Finally finished my radius cutter. It is a copy of the Sherline's tool, at least as close as I could do from their ads. I posted a picture in files on a folder named Radius cutter. Everything came out great except the body anodyzing which turned out purple instead of black, I'l have to redo it and use dark blue as in the supports which came out with a nice dark blue, almost black. Thanks for all the suggestions and help! Rogerio Odriozola ----------------- Date: Tue, 2 Jan 2001 00:29:08 EST From: SLEYKINx~xxaol.com Subject: Ball Turning tool finished :) I have been thinking about all the different ways to make ball turning tools for my lathe and finally came up with a solution that works for me. Sort of a take off on the ones discussed on RCM using a boring head. I used the tool holder from the QC kist I bought from Harbor freight that is for holding a drill chuck. I made a brass bushing with a 1/2" bore and a new spindle for the boring head with a 1/2" shaft long enough to pass through the toll holder/bushing and attach a handle. I then made a short boring bar and mounted a HSS cutting tool 90* to the normal way and presto I can make nice shiney round ball on the lathe now. First one is going on the handle for the ball turning tool :) I just used a long 1/2" bolt and the hex head is not real comfortable. I ground a round nosed tool bit and that seems to work well with this setup. Regards Glenn Neff Medford, OR --------------------------- Date: Mon, 21 May 2001 04:31:21 -0000 From: "Doug Powell" <4machiningx~xxhome.com> Subject: Re: Peatool ball turning jig? The Taig radius turning attachment is part # 1210 and was introduced about a year and a half ago. Taig lists it for $19.50. Doug Powell Taig Tools Dealer ---------------------------- From: Ron Ginger Date: Thu Jul 6, 2000 9:34 am Subject: Re: [sherline] Ball turning tools(Was Rotating Table) Bill Rutiser wrote: > > That would be Joe Osborn of OMW Metalcrafts. www.omwmetal.com > > The OMW tool rotates a bit in a horizontal plane around vertical > > axis. The Sherline device rotates the bit in a vertical plane > > around a horizontal axis. I don't immediately see how the Sherline > > design could be used for the orginal poster's problem but > > OMW's should work. The Sherline one would work the same way- its center of rotation is on the centerline of the lathe, just in the other plane. You would simply adjust the tool to extend out past the centerline by the desired radius, where for turning a ball you place the tool below the centerline. Identical to Joes device, just his is mounted 90 degrees to the Sherline version. Both tools would suffer from long overhang of the tool if you were trying to do a very big concave radius. ron ----------------------------- From: "Bill Rutiser" Date: Thu Jul 6, 2000 10:14 am Subject: Re: [sherline] Ball turning tools(Was Rotating Table) The original poster's problem was to produce a groove with circular cross section. In that application the ball turning tool's axis must be displaced from the spindle's axis. With the OMW tool this is accomplished by adjusting the cross slide. The Sherline design would need some sort of vertical adjustment. Bill Rutiser Gaithersburg, MD -------------------------- From: Ron Ginger Date: Thu Jul 6, 2000 11:50 am Subject: Re: [sherline] Ball turning tools(Was Rotating Table) You are correct. The OMW attachment is more flexible in that regard. The Sherline one can only make balls whose axis are concentric with the work. ron ------------------------- From: rdavx~xxv... Date: Fri Jul 7, 2000 3:49 pm Subject: Re: Rotating Table --- In sherlinex~xxegroups.com, Ron Ginger wrote: > Robert Davies wrote: > > I am cutting a radius in the center of a 1/4" aluminum rod, like this: > I dont think a rotary table is the way to do this- its a job for one of > several ball turning tools. Sherline sells one, that mounts over the top > of the work. There is also a fellow that sells a nice one, he demoed at > NAMES, but I dont recall his name or URL. There are also MANY plans for > ball turning tools in various model engineering magazines. > For one this small I would use a form tool. Just grind the end of a 1/4" > lathe tool to the required radius and plunge cut it straight in. Unless > the grove you want to cut requires extremely accurate radius- maybe to > roll ball bearings in- a freehand grind up against a template should be > fine. Make a template by drilling and reaming a very clean hole in a > piece of sheet metal, then cut away one half the metal to leave a > half-round template. Hold this up to a light against the tool and grind > away until the fit is as good as you can make it. > Form tools can be tricky to get right- they will chatter if made to wide > or taking to deep a cut, but since you are doing 1/4" rod the radius can > not be very large. ron Thanks, Ron. I am trying to do cuts similar to what is shown in the Sherline Manual "Tabletop Machining" on pages 214 and 327. I think my problem is that both of those pictures show setups with the mill rather than with the lathe/mill column. I just purchased a mill xy table and I expect this will resolve my problem. Robert Davies ----------------------------------- Date: Wed, 4 Feb 2004 06:47:49 -0500 From: Kuechenmeister Subject: Radius Turning I started out this weekend, intent on making some sort of a ball turning attachment for my lathe. I looked through a couple magazines and realized that the compound is a pretty good ball turner, as it is installed on the lathe. This sure looks like an obvious way to turn an occasional radius. Besides increased wear on the mount, is there any other problem that I'm overlooking? Thanks, Dave Kuechenmeister Lawrenceville, GA ---------------- Date: Wed, 4 Feb 2004 13:44:33 -0000 From: "Ernest Lear" Subject: Re: Radius Turning Dave How are you going to control the direction and cut of the tool? A loose compound held in the hand to control the cut could give you a big surprise when the tool dig into the metal that you are trying to shape. And don't forget, the support casting of the mount on the cross slide is very brittle and will break very easily when the cutting tool dig in. This is very well helped by the loose compound, the leverage between the tool tip and the centre of the mount and the sharp rapid downward force applied at the tool tip. Regards Ernest ---------------- Date: Wed, 4 Feb 2004 09:41:43 EST From: jmartin957x~xxaol.com Subject: Re: Radius Turning It works, I've done it. Not for balls, but for concave pieces. Turning a new spherical washer for the toolpost, for example. There are a few precautions, most of which are common sense. The compound swivel has to be adjusted pretty closely. Loose enough so that it will just swivel, but tight enough so that there is no rocking or other play. You need as much control over the swiveling as possible. A long bar clamped to the back of the Armstrong tool holder, or clamped into the toolpost along with the bit, will allow you to feed slowly and steadily. The bit should be ground so that it is pretty much neutral. In particular, you don't want one with so much rake that it wants to self-feed. Feed slowly and with small depth of cut, and listen and feel what the lathe is trying to tell you. Convex surfaces may be more difficult than concave, due to clearance problems and the position of the cutting edge versus the axis of the compound swivel. You might have to work with the compound facing backwards, or with the compound in the normal position but cutting on the back side of the piece with an upside-down cutter. Adapt and improvise. And let us know of your success or failure, so that everyone else doesn't have to reinvent the process. I've also done some hand turning - turning steel with hand held tools as on a wood lathe. Generally for concave rather than convex surfaces, for profiles too large for a form tool. Main concern there is keeping tool overhang to a minimum. John Martin -------------------- Date: Wed, 4 Feb 2004 09:52:42 EST From: Sagebush9x~xxaol.com Subject: Re: Radius Turning I've tried that on my 12", 28990-it works OK for pretty small radii, but you can't get enough offset from center to make a very big ball-on the 12", it is rigid enough if you are VERY careful & take real light cuts, but I don't know if I'd try it on the older smaller lathes W/a a lighter compound...a recent issue of HSM or MW had plans for a pretty simple ball turner, don't remember which mag right now. HTH Ron in CO... -------------------- Date: Wed, 04 Feb 2004 11:22:08 -0600 From: Jon Elson Subject: Re: Radius Turning The big problem is to make a toolpost that holds a tool BEHIND the center of rotation of the compound. You can't do it with a standard toolpost, the way most lathes are set up. Jon ----------------------- Date: Wed, 04 Feb 2004 16:30:50 -0000 From: "kplus13" Subject: Re: Radius Turning Thanks for the advice. The ball turner in the latest HSM/MW [3-part article started with Nov/Dec 2003] is what I will probably make, if only for the larger radii available. What made me think of using the compound is that this accessory just sits on top of the compound like a tool holder would. I've got some one inch brass that I am going to experiment on. I'll let you know how it goes. Regards, Dave Kuechenmeister --------------------- Date: Wed, 04 Feb 2004 10:35:47 -0600 From: xlch58x~xxswbell.net Subject: Re: Re: Radius Turning There was an article years ago in one of the village press magazines that showed how to make a plate to insert between the compound and its mount. It bolted to the cross slide and had several predrilled holes for mounting the compound to cut common radiuses. Very simple. This idea could be adapted to the Atlas, though it was applied there to a Southbend. Charles --------------------- Date: Wed, 4 Feb 2004 12:00:00 -0500 From: "Dr Robert Harms" Subject: Re: Re: Radius Turning I have never needed to turn a precise radius so if your need is to do so discount what follows (although Im not sure why the radius would need to be exact unless it was to fit into some corriisponding type of female recess). All of the radius turning that I have needed to do is cosmetic like on acorn nuts and the like. To make such products, I simply rough them in and then profile them with a 4 1/2 inch hand held grinder while the piece is spinning in the chuck. Merely cover the ways and grind away. The fact that they are spinning in the chuck assures that they are symmetrical. Multiple pieces can be compared to templates. Again, this is for cosmetic rather than precise pieces. --------------------- Date: Thu, 05 Feb 2004 02:40:03 -0000 From: "mikehenryil" Subject: Re: Radius Turning Jerry Howell has a set of plans for a ball turner/radiusing attachment. It's designed for a different lathe, but it wasn't hard to modify the base to fit a Craftsman 12" lathe. You can see a picture of the the one I made for my old Craftsman lathe in Jerry's gallery: http://www.jerry-howell.com/Cust-Pix-5.html The plans were good quality and only $10: http://www.jerry-howell.com/Radius.html Mike ------------------------ Date: Thu, 5 Feb 2004 08:53:10 -0000 From: "Alan Barnett" Subject: Re: Re: Radius Turning Have a look here under Home Shop Software it might help. http://www.geocities.com/mklotz.geo/#shop Regards Alan ------- NOTE TO FILE: Marv Klotz's site has MANY useful programs for the home shop machinist to simplify cutting gears, knurling, etc. etc. etc. ------- Date: Wed, 23 Feb 2005 18:54:38 -0500 From: "Chris Boyer \(CB\)" Subject: Re: Ball turning [Prints_and_Plans group] "wesley5060" wrote: > Hi all any one got a drawing on how to make a ball turning attachment > for the lathe please. wes Not a drawing but see: http://bedair.org/Ball/ball.html There is a lot of useful info on the other pages as well. Many versions of this tool have been made. ------- Date: Fri, 25 Feb 2005 04:51:19 -0000 From: "Ned Seith" Subject: Re: Ball turning [Prints_and_Plans group] Greetings, I use a custom carbide insert tool holder for ball turning. Pictures: http://users.rcn.com/seiths/projects/tooling/index.html Ned ------- Date: Thu, 24 Feb 2005 14:42:46 +0000 From: Clive Foster Subject: Re: Ball turning [Prints_and_Plans group] Wes, there are loads of variations on the horizontal sweep design available as plans from various magazine back numbers. I've got at least 4 in the archives varying from rudimentary to excessively complicated multi- adjustable worm drive beasts. Depending on your particular time/work/scrapbox contents situation I think the best way of doing the job is to make a vertical sweep version using a cheap boring head for the tool holder. Most of the inexpensive boring heads screw on the arbor so all you have to make is a block for the toolpost bored on centre height for the pivot and a hefty pivot bar with a handle one side and a threaded spigot to fit the boring head on the other. By far the best solution if you have a milling machine as now you have a dual purpose tool! That's the way I'm going to make mine when I've collected enough round tuits! Clive ------- Re: Ball/Radius turning tool [atlas_craftsman] Posted by: "Glenn N" sleykinx~xxcharter.net Date: Wed Jan 17, 2007 9:56 am ((PST)) "mrkharriss" wrote: > Hi, does anyone own one of these? If so, where did you get it and how > well does it work? Having only just bought my 10" F model, I'm in the > process of assembling a selection of tools which will be of use to me > as asnd when future projects arrive. Has anyone made one and if so, > can you please point me towards the plans? Thanks Mark I made one by mounting a boring head on a shaft sized to fit the boring bar holder on my QCTP. Put a cutter bit in a piece of rod I broached a square hole in and I can do a ball close to 2" in dia very quickly and easily. I posted pictures of it many moons ago but if you can't find them or want some more holler. Glenn ------- Re: Ball/Radius turning tool Posted by: "Joe R" jromasx~xxcolumbus.rr.com Date: Wed Jan 17, 2007 4:15 pm ((PST)) Mark: I recently made one of these. http://alisam.com/page/14g9f/Metalworking.html I also made one like Glenn mentioned. I liked the one in the link better except for one thing. If you don't have a broach just drill a round hole! Otherwise you'll be trying to get the bit to fit right. ------- Re: Ball/Radius turning tool Posted by: "Jim" clipper_2x~xxcharter.net Date: Wed Jan 17, 2007 5:36 pm ((PST)) Go to the files section and check this one out. http://groups.yahoo.com/group/atlas_craftsman/files/Ball%20turn ing%20attachment/ I like this one about the best of all the designs I've used. Jim ------- Re: Ball/Radius turning tool Posted by: "Zort C. Brown" mtrsicklemanx~xxearthlink.net Date: Wed Jan 17, 2007 6:50 pm ((PST)) Mark: I just bought a ball turning frame kit on eBay. Nice quality -- just needs to be finished. His current auction is # 180075693819 He also has a website where he sells them around for $25 + shipping. www.alisam.com Zort Brown Lincoln, NE ------- Re: Ball/Radius turning tool Posted by: "Bruce Koch" tkd_master38x~xxyahoo.com Date: Wed Jan 17, 2007 7:25 pm ((PST)) Hey Gang, I have a Holdredge that I bought on Ebay some time back; it is a big heavy duty thing and well constructed. It mounts onto the t slot in the compound. So far I have not tried it on my Craftsman or Atlas, but afraid that it will be too big for a small machine to handle. It worked fine on the 13 " Harrison at school. A smaller version would be great. This thing will do concave and convex, so it really handy, much faster than grinding a radius tool. Here is another thought, for a small lathe something that fits onto the cross slide rather than the compound might be ideal. These things do not have to be mounted vertically; no reason that it cannot be mounted horizontally and swing upward to turn a radius. It is my understanding that Sherline mini lathes use such an arrangement. One more thought, why all the fuss over broaching a square hole? HSS comes in round stock and is just as easy to grind a tool on it. Save a lot of hassle. Bruce ------- Re: Ball/Radius turning tool Posted by: "azbruno" azbrunox~xxyahoo.com Date: Wed Jan 17, 2007 8:16 pm ((PST)) Guy Lautard, in his excellent book "The Machinist's Bedside Reader", discussed a method of turning radii using a parting tool. In the same vein, I do a lot of radius ends using nothing more than a turning tool and math. A radius is a part of a circle and the points on a circle can be calculated with a formula. Earlier this week, I was putting 5/16" radius ends on 5/8" diameter rods, the ends being a semicircle. Using a series of successive cuts where I'd move the cross slide in .010" on each cut, and then following up with a file, I could do the job in about 5 minutes. I do this a lot, so I made a simple word macro that lists out all the cross slide and carriage movements. Of course, one does need accurate measurements and I have a DI on the cross slide and on the carriage. My next task is to radius from the front, not the end, so I'll need to use the Lautard method with the parting tool, I suspect. Bruno ------- Re: Ball/Radius turning tool Posted by: "n8as1x~xxaol.com" n8as1x~xxaol.com Date: Wed Jan 17, 2007 8:34 pm ((PST)) FWIW ...have made balls, radii, curves using hand held scrapers made from old files used in manner of a wood lathe ...yes works on mild steel also ...use back of bit holder for a rest & grind a rt /left skew from flat file, round point from 1/2 round & round files.....earliest metal lathe work was done in this manner & even 80 yrs ago, fillets in flanges were smoothed this way best wishes docn8as ps ...for one-offs, it goes faster than setting up for ball turning ------- Re: Ball Turning on Taig Lathe [taigtools] Posted by: "Rich Crook" richcrook9418x~xxyahoo.com Date: Sat Jul 7, 2007 1:21 pm ((PDT)) At 11:10 AM 7/7/2007, you wrote: >I've purchased a Small Ball Turning Attachment from omw: >http://www.omwcorp.com/pr od_srt.shtml >Can anyone offer any advice using this item? What's the best way of >setting up the tool and using the attachment? Make sure your tool point is centered vertically, & take light passes till you get a feel for it. If you can, measure the distance from the face of the movable "C" toolholder to the pivot centerline - then you can set the tool to a specific cutting radius with a depth gage or mike. If you have a caliper with a depth rod, use a parallel faced block (of known thickness) with a hole drilled in it for the depth rod to pass thru. Figuring out when the pivot center is exactly on the spindle center isn't hard *if* you know what the cutting radius is set to. If you make a straight tool holder (to replace the "C" holder) you can cut concave radii with it. I've used a much bigger version of this (on a bigger lathe) to make hemispherical plastic shells with a constant wall thickness; it worked very nicely. Note: for a full concave hemisphere, you'll need a tool with an offset tip, like a boring bar, or an OD turning tool. Otherwise, use a centered "V" point tool (like a threading tool.) Rich ------- Re: Ball turning attachment [atlas_craftsman] Posted by: "Russ Kepler" russx~xxkepler-eng.com Date: Thu Nov 15, 2007 6:49 am ((PST)) On Wednesday 14 November 2007 22:26:43 pjamesanderson wrote: > Anybody have one for sale or know where I can get one? I dont have > time to make one and would like to buy one for my 12" craftsman. I can > pay with paypal if desired. Thanx...Pete The Shaplane radius tools from Eagle Rock are OK. Here's a link: http://www.eaglerockonline.com/index.php?Catalog=View&ProductLine=32 You can sometimes find them on eBay. Other than that the Holdridge tools are about it. I made the MLA ball turning attachment and it went pretty well - it's a fast kit to make. ------- Re: Ball turning attachment Posted by: "Russ Kepler" russx~xxkepler-eng.com Date: Thu Nov 15, 2007 10:06 am ((PST)) On Thursday 15 November 2007 Jay Greer wrote: > Question, Will the Shaplane radius tool work on the six inch Atlas? Nope. You might make something that would work, but the smallest of the Shaplane tools is too big for the 6". ------- Re: Ball turning attachment Posted by: "Brian" brianmc4x~xxcomcast.net Date: Thu Nov 15, 2007 7:16 am ((PST)) I would not bother with a ball turning attachment after using a corner rounding end mill, mounted in boring bar tool post and getting good results. The only problem is that you're cutting in reverse from the back side. Brian ------- Re: Ball turning attachment Posted by: "Jim Ash" ashcanx~xxearthlink.net Date: Thu Nov 15, 2007 10:18 am ((PST)) Not that this really answers your question, but: If you've just got one ball-turning job to do, you can skip the attachment and use the method described in Guy Lautard's Bedside Readers. It basically means cutting the ball in steps, then bluing and lathe-filing until the blue stripes disappear. I've turned a few balls this way. I put together a spreadsheet showing me the coordinates I need for each cut, then print it and check each step off as I go. It's obviously more tedious than using a ball-turning attachment, but for my frequency of need I can't justify spending the bucks. Jim Ash ------- RE; Ball turning attachment Posted by: "wkmacy" wkmacyx~xxgso.uri.edu Date: Thu Nov 15, 2007 1:10 pm ((PST)) Hello all -- check out Alisam Tools at http://alisam.com/page/14g9f/ Metalworking.html for 2 sizes of ball turning kits at very reasonable prices. The frames are laser-cut and require only drilling several holes, a short length of 1/4 in drill rod, and a few set screws to complete. NO milling is needed, but you must be able to drill the axle/pivot holes accurately. Best of luck, Bill from RI ------- Re: Ball turning attachment Posted by: "Bobby May" widgitsx~xxsbcglobal.net Date: Thu Nov 15, 2007 12:07 pm ((PST)) Check out the files directory on the atlas_craftsman main page. Real cool layout from the 60's for how to make and use one of these radius attachments. Different from a Holdridge type, just swings the compound rest. Something to think about, pretty cool!!! Later Bobby -------