Re: [Emc-users] Ballnuts
On 15 December 2012 05:14, Przemek Klosowski przemek.klosow...@gmail.com wrote: I think a tensile strength of a typical carbon steel M3 bolt should be around 4kN---why does Inventor think this has to be torqued up to 78 tons? Also, M6 should be 4x stronger---but Inventor thinks you need 1/15 the number, not 1/4. I don't get what assumptions go into those numbers. It isn't exactly 4 x (as the effective diameters are not 2:1 because of the thread depth), but you have spotted an error. Inventor was (for some random reason) working on the basis of an M3 x 1.25 bolt. Such a bolt has a tiny CSA under the thread. Using the real pitch (0.5mm) gives a rather more convincing answer. This is the sort of error you make when you are too lazy to calculate properly and trust computers instead. My servo has a max torque of 9Nm, and a 4:1 ratio drive to a 5mm pitch ballscrew. That gives me (I think) a peak axial force of 45kN. So, around 15 M3 bolts should be OK. Using the bolted joint calculator says 150 bolts. I think it is limiting on thread pressure. However: The whole assembly is mounted into the casting by two 3/8 UNC bolts. Treating those as a mechanical fuse seems like suggest that I probably don't need much more than 8. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
2012/12/15 Przemek Klosowski przemek.klosow...@gmail.comhttps://mail.google.com/mail/u/0/?view=cmfs=1tf=1to=przemek.klosow...@gmail.com I think a tensile strength of a typical carbon steel M3 bolt should be around 4kN---why does Inventor think this has to be torqued up to 78 tons? I would not agree here. For M3 the body diameter is 2.5mm, the section area is 6.25mm2 Let the ultimate strength be 250/mm2 6.25 * 250 = 1562N The thread develops a stress concentration, and a significant safety factor must be considered. So actually M3 holds less 500N. -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 15 December 2012 14:39, Andrew parallel.kinemat...@gmail.com wrote: Let the ultimate strength be 250/mm2 I wasn't planning on using cheese :-) Hex-head bolts are normally at least grade 8.8, so 600MPa proof and 800MPa UTS. http://www.engineeringtoolbox.com/steel-bolts-metric-grades-d_1428.html -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 12/15/2012 8:59 AM, andy pugh wrote: Treating those as a mechanical fuse seems like suggest that I probably don't need much more than 8. Treating those as a mechanical fuse seems like suggest that I probably don't need much more than 8. Thinking of these as a mechanical fuse is a very good idea.. I have utilized socket head cap screws in this manner before with some large ball screw drives.. when I realized too late that the hard limit switches were inoperative due to improper wiring.. :-( It was fairly easy to replace the screws, correct the wiring and continue. Dave -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On Fri, 14 Dec 2012 00:04:34 +, you wrote: On 13 December 2012 23:39, Andrew parallel.kinemat...@gmail.com wrote: The belt profile is rather simple HTD 5M. It was cut with nearly round shaped fly cutter, then some fillets made on sharp edges of teeth. Ah, I am typically using T5 belts, which are squarer. Andy - very easy to make HTD pulleys, drill holes for teeth on correct PCD then turn off excess to correct OD. The half holes left make the teeth. A quick clean on a 3M abrasive wheel cleans off the sharp edges and your done. If you do a search for making HTD pulleys there is detailed info on making them that way. Steve Blackmore -- -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On Fri, Dec 14, 2012 at 12:36 AM, andy pugh bodge...@gmail.com wrote: On 14 December 2012 00:21, andy pugh bodge...@gmail.com wrote: It is rather a tight fit under the table, between the ways. https://picasaweb.google.com/lh/photo/7PPw4pWFfZy_jHDMq_KbmdMTjNZETYmyPJy0liipFm0?feat=directlink The thing that grates with me is the rear contact of the belt to the casting. if the encoder is on the motor there will be a small hysteresis to the movement due to the friction. if on the screw then I can see a small effect on the loop as the servo will move and not the screw. can you rotate 90 degrees and hang the motor below. Dave Caroline -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 14 December 2012 09:15, Dave Caroline dave.thearchiv...@gmail.com wrote: https://picasaweb.google.com/lh/photo/7PPw4pWFfZy_jHDMq_KbmdMTjNZETYmyPJy0liipFm0?feat=directlink The thing that grates with me is the rear contact of the belt to the casting. Let me put your mind at rest and point out the tensioning/guide roller which has rather slipped out of position, and has lost its mounting boss. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 14 December 2012 05:08, Przemek Klosowski przemek.klosow...@gmail.com wrote: The collar squeezes the inner race, so it presumably is split, with a gap between the front and rear race, not reflected in the drawing, right? Yes. I didn't bother modelling that. I realise that seems odd when I did model the individual balls, but I have a pretty quick way of modelling ball bearings (using a shared sketch and revolves around two different axes) Perhaps use a split housing that has thick enough bosses in front of and behind the bearing outer race, so that you can bolt the cog wheel and ballnut to them, and another pair of mating bosses on top of the bearing, so that you can bolt the two halves together; the last two mating bosses would be right behind of the cog wheel, because it looks like their outside diameter could be larger than the cog wheel diameter. I think I know what you are saying. I have run out of diameter to the right of the casting mating face, but there might be room for a bolted flange inside the casting. it would probably make for a somewhat more straightforward assembly process too. If I did go for HTD pulleys as suggested by Steve then that section could be machined in one piece, and spigotted by the bearing outer. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
You know you can buy rotating nut assemblies, such as here: http://hiwin.com/html/ball%20screws/r1.html - Original Message - On 14 December 2012 05:08, Przemek Klosowski przemek.klosow...@gmail.com wrote: The collar squeezes the inner race, so it presumably is split, with a gap between the front and rear race, not reflected in the drawing, right? Yes. I didn't bother modelling that. I realise that seems odd when I did model the individual balls, but I have a pretty quick way of modelling ball bearings (using a shared sketch and revolves around two different axes) Perhaps use a split housing that has thick enough bosses in front of and behind the bearing outer race, so that you can bolt the cog wheel and ballnut to them, and another pair of mating bosses on top of the bearing, so that you can bolt the two halves together; the last two mating bosses would be right behind of the cog wheel, because it looks like their outside diameter could be larger than the cog wheel diameter. I think I know what you are saying. I have run out of diameter to the right of the casting mating face, but there might be room for a bolted flange inside the casting. it would probably make for a somewhat more straightforward assembly process too. If I did go for HTD pulleys as suggested by Steve then that section could be machined in one piece, and spigotted by the bearing outer. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Todd Zuercher mailto:zuerc...@embarqmail.com -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 14 December 2012 14:56, Todd Zuercher zuerc...@embarqmail.com wrote: You know you can buy rotating nut assemblies, such as here: http://hiwin.com/html/ball%20screws/r1.html I didn't know that, no. I think one would probably fit, too. However they all seem to have 1:1 pitch to diameter? -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
Dave Caroline wrote: if the encoder is on the motor there will be a small hysteresis to the movement due to the friction. if on the screw then I can see a small effect on the loop as the servo will move and not the screw. can you rotate 90 degrees and hang the motor below. I put the encoders on the ballscrew, and have had no problem with it. I do tension the belt VERY tightly to eliminate any flapping, and the belt is quite short, the shafts are about 3 apart. Jon -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
2012/12/14 Jon Elson el...@pico-systems.com: Dave Caroline wrote: if the encoder is on the motor there will be a small hysteresis to the movement due to the friction. if on the screw then I can see a small effect on the loop as the servo will move and not the screw. can you rotate 90 degrees and hang the motor below. I put the encoders on the ballscrew, and have had no problem with it. I do tension the belt VERY tightly to eliminate any flapping, and the belt is quite short, the shafts are about 3 apart. The small problem here is that putting encoder on ballscrew is just a waste of encoder as the nut is rotating and the screw is fixed :)) -- Viesturs If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 13 December 2012 23:39, Andrew parallel.kinemat...@gmail.com wrote: Also I'd turn the motor tail to the left, and make the hollow shaft a bit shorter if needed. I don't know if that was advice to me, but it looks like I need to do that, as I just realised that I can't get to the table clamps with my original positioning. (I don't know if I will ever want to, but the table swings on the mill. This might be rather pointless on a CNC machine, but ought to make for easy setup for hobbing in the horizontal spindle) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 14 December 2012 05:08, Przemek Klosowski przemek.klosow...@gmail.com wrote: Perhaps use a split housing that has thick enough bosses in front of and behind the bearing outer race, so that you can bolt the cog wheel and ballnut to them, and another pair of mating bosses on top of the bearing, so that you can bolt the two halves together; I can fit M3 bolts quite nicely. However the Inventor bolted joint designer reckons I need 175 of them. (12 M6 bolts is fine too) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
Viesturs Lācis wrote: The small problem here is that putting encoder on ballscrew is just a waste of encoder as the nut is rotating and the screw is fixed :)) Oh, yes, in this case, the encoder would need to either be on the motor, or driven by a separate belt from the rotating nut. If one was really resourceful, you could get a large-bore hollow-shaft encoder disc or resolver and mount it directly on the encoder, but those are usually expensive. Otherwise, I think an encoder on the motor would be perfectly fine. Jon -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On Fri, Dec 14, 2012 at 8:04 PM, andy pugh bodge...@gmail.com wrote: I can fit M3 bolts quite nicely. However the Inventor bolted joint designer reckons I need 175 of them. (12 M6 bolts is fine too) I think a tensile strength of a typical carbon steel M3 bolt should be around 4kN---why does Inventor think this has to be torqued up to 78 tons? Also, M6 should be 4x stronger---but Inventor thinks you need 1/15 the number, not 1/4. I don't get what assumptions go into those numbers. -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
Jon Elson wrote: Viesturs Lācis wrote: The small problem here is that putting encoder on ballscrew is just a waste of encoder as the nut is rotating and the screw is fixed :)) Oh, yes, in this case, the encoder would need to either be on the motor, or driven by a separate belt from the rotating nut. If one was really resourceful, you could get a large-bore hollow-shaft encoder disc or resolver and mount it directly on the encoder, but those are usually expensive. should read rotating nut not encoder in the above line -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
I like #1 also. Use Locktite on the threads? #2 has to much cantelever on the bearing. #3 isn't bad but looks more complex at first glance and the bearing appears to not be nearly as beefy, however it might be more than adequate. Looks like you are making an actuator of sorts. I could use a source for some of those, but scaled down just a bit. Ball screw actuators seem to be very expensive.. Dave On 12/13/2012 5:11 PM, andy pugh wrote: I have designed three alternatives. They all use bearings that I know I can get, rather than bizarre exotica. The first idea is: https://picasaweb.google.com/lh/photo/EqgIdXH-kCH8I90oYKfm2dMTjNZETYmyPJy0liipFm0?feat=directlink This actually uses a car wheel bearing, which is angular-contact and has adjustable preload. The preload is adjusted by the orange threaded collar. The pulley screws on and in doing so it clamps the outer race. Clearly some means is needed to stop it unscrewing again. I am not sure I have the available length for this design, though. The next alternative is more conventional, and uses a double-row angular-contact bearing (3809). This bearing is not adjustable, and looks like it would be a lot less stiff than the first one. https://picasaweb.google.com/lh/photo/DELJ44ystXfa1HavUrYFmtMTjNZETYmyPJy0liipFm0?feat=directlink This requires a more complex casting shape to get the belt into place, and a separate end cover. It also puts the bearing a long way from the belt tension load. The third design uses the second bearing again, but in a better place. https://picasaweb.google.com/lh/photo/X9ZXwL-oMXpF9cc6wAIbQNMTjNZETYmyPJy0liipFm0?feat=directlink This design is growing on me, the only problem being that I can't quite see how to retain the bearing outer race in the casting. It has a nice direct drive from the belt to the ballnut. I think the first option looks like the best, if it can fit. For reference I have a 40mm OD on the ballnut and a 76mm diameter hole 90mm deep in the machine bed. This means the protrusion to the left of the casting in the pictures has to be shorter than 90mm and less than 75mm dia. -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 13 December 2012 22:38, Dave e...@dc9.tzo.com wrote: #3 isn't bad but looks more complex at first glance and the bearing appears to not be nearly as beefy, It also isn't held in very well, and I am struggling to think of a way to fix that. Looks like you are making an actuator of sorts. It's the X axis for my mill. The alternative is to have it sticking out the end of the table with a long loop of wire. And I am bound to use it as a hip-detector when doing other things. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
2012/12/14 andy pugh bodge...@gmail.com I have designed three alternatives. They all use bearings that I know I can get, rather than bizarre exotica. The first idea is: https://picasaweb.google.com/lh/photo/EqgIdXH-kCH8I90oYKfm2dMTjNZETYmyPJy0liipFm0?feat=directlink This actually uses a car wheel bearing, which is angular-contact and has adjustable preload. The preload is adjusted by the orange threaded collar. The pulley screws on and in doing so it clamps the outer race. Clearly some means is needed to stop it unscrewing again. I am not sure I have the available length for this design, though. The next alternative is more conventional, and uses a double-row angular-contact bearing (3809). This bearing is not adjustable, and looks like it would be a lot less stiff than the first one. https://picasaweb.google.com/lh/photo/DELJ44ystXfa1HavUrYFmtMTjNZETYmyPJy0liipFm0?feat=directlink This requires a more complex casting shape to get the belt into place, and a separate end cover. It also puts the bearing a long way from the belt tension load. The third design uses the second bearing again, but in a better place. https://picasaweb.google.com/lh/photo/X9ZXwL-oMXpF9cc6wAIbQNMTjNZETYmyPJy0liipFm0?feat=directlink This design is growing on me, the only problem being that I can't quite see how to retain the bearing outer race in the casting. It has a nice direct drive from the belt to the ballnut. I think the first option looks like the best, if it can fit. For reference I have a 40mm OD on the ballnut and a 76mm diameter hole 90mm deep in the machine bed. This means the protrusion to the left of the casting in the pictures has to be shorter than 90mm and less than 75mm dia. Andy, you might want to take a look at my design http://img338.imageshack.us/img338/7208/screenshot20121214c.png http://img255.imageshack.us/img255/7208/screenshot20121214c.png The green part is a hollow shaft, there are two angular contact roller bearings, preload is adjusted by two nuts I had to cut the timing pulley on the hollow shaft, and consider many other limitations to keep it small as a part of a joint. But I tried to keep it as simple as possible. Regards, Andrew -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 13 December 2012 22:56, Andrew parallel.kinemat...@gmail.com wrote: I had to cut the timing pulley on the hollow shaft, and consider many other limitations to keep it small as a part of a joint. That would probably help in my case too, but how did you get the correct tooth profile? ( want a 4:1 ratio too, 15 m/min is rather more than I would need) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 12/13/2012 5:52 PM, andy pugh wrote: On 13 December 2012 22:38, Dave e...@dc9.tzo.com wrote: #3 isn't bad but looks more complex at first glance and the bearing appears to not be nearly as beefy, It also isn't held in very well, and I am struggling to think of a way to fix that. Looks like you are making an actuator of sorts. It's the X axis for my mill. The alternative is to have it sticking out the end of the table with a long loop of wire. And I am bound to use it as a hip-detector when doing other things. So where does it go? I'm having trouble visualizing how to introduce this drive scheme without reducing the amount of available travel of the bed (I assume this is a retrofit). The older I get the more I resemble that hip-detector remark. Regards, kent -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 13 December 2012 23:13, Kent A. Reed kentallanr...@gmail.com wrote: So where does it go? I'm having trouble visualizing how to introduce this drive scheme without reducing the amount of available travel of the bed (I assume this is a retrofit). You are right, it is 28mm thick, and the original nut housing (ballnut was an option, and it even rotated in bearings, though that was to allow for use of the drive for the rotary axis) was proobably 3/4 thick, so I will lose some of the travel. Losing the other power-feed I might get it back at the other and, and I doubt I need all of it anyway. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
Make the bearing larger, make the pulley larger and use long bolts through the ball screw flange to clamp everything together inside the ID of the bearing? On 12/13/2012 5:52 PM, andy pugh wrote: On 13 December 2012 22:38, Davee...@dc9.tzo.com wrote: #3 isn't bad but looks more complex at first glance and the bearing appears to not be nearly as beefy, It also isn't held in very well, and I am struggling to think of a way to fix that. Looks like you are making an actuator of sorts. It's the X axis for my mill. The alternative is to have it sticking out the end of the table with a long loop of wire. And I am bound to use it as a hip-detector when doing other things. -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 13 December 2012 23:39, Andrew parallel.kinemat...@gmail.com wrote: The belt profile is rather simple HTD 5M. It was cut with nearly round shaped fly cutter, then some fillets made on sharp edges of teeth. Ah, I am typically using T5 belts, which are squarer. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On Dec 14, 2012 1:39 AM, Andrew parallel.kinemat...@gmail.com wrote: For 4:1 I'd better put larger timing pulley with taper bush on that hollow shaft, just next to the nuts. Also I'd turn the motor tail to the left, and make the hollow shaft a bit shorter if needed. Also, if the timing pulley is large enough, it better get moved over the ballnut flange. Similar to your design #2 Andrew -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 14 December 2012 00:06, Dave e...@dc9.tzo.com wrote: Make the bearing larger, make the pulley larger and use long bolts through the ball screw flange to clamp everything together inside the ID of the bearing? It is rather a tight fit under the table, between the ways. The problem is holding the bearing into the cast housing, and whereas I could do that using the flange bolts, I think that would stop the nut rotating :-) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 14 December 2012 00:21, andy pugh bodge...@gmail.com wrote: It is rather a tight fit under the table, between the ways. https://picasaweb.google.com/lh/photo/7PPw4pWFfZy_jHDMq_KbmdMTjNZETYmyPJy0liipFm0?feat=directlink The servo is slightly fatter than the gap under the square slide, or it would be closer in and pointing the other way for a shorter (and better) belt run. Ball nut OD is 40mm and the flange is 61mm. The gap under the bed is 77.6mm. The main problem is the availability of suitable bearings in suitable sizes. Despite appearances, this isn't a lot more complex than a spinning-screw, as I would still need a motor mount and a ballscrew mount, suitable bearings, and their clamping arrangements. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 12/13/2012 7:36 PM, andy pugh wrote: Despite appearances, this isn't a lot more complex than a spinning-screw True, but you could probably buy the screw support thrust bearing off the shelf, if you wanted to do that. Dave -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On Thu, Dec 13, 2012 at 5:11 PM, andy pugh bodge...@gmail.com wrote: The first idea is: https://picasaweb.google.com/lh/photo/EqgIdXH-kCH8I90oYKfm2dMTjNZETYmyPJy0liipFm0?feat=directlink This actually uses a car wheel bearing, which is angular-contact and has adjustable preload. The preload is adjusted by the orange threaded collar. The collar squeezes the inner race, so it presumably is split, with a gap between the front and rear race, not reflected in the drawing, right? Otherwise, I don't see how you'd preload it. As to the outer race, I agree that transfering the torque through cog wheel/housing thread is iffy. Perhaps use a split housing that has thick enough bosses in front of and behind the bearing outer race, so that you can bolt the cog wheel and ballnut to them, and another pair of mating bosses on top of the bearing, so that you can bolt the two halves together; the last two mating bosses would be right behind of the cog wheel, because it looks like their outside diameter could be larger than the cog wheel diameter. -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] Ballnuts
Has anyone ever seen a bearing press-fitted to the outside of a ballnut? I am designing a rotating-nut system, and simply pressing the ballnut into the middle of a double-row angular contact bearing would be very simple. I suppose an alternative would be to look at threading a part of the OD of a flanged ballnut. http://simplybearings.co.uk/shop/p150726/3808B2RSRTVH+Rubber+Sealed+Double+Row+Angular+Contact+Ball+Bearing+40x52x10mm/product_info.html For example looks like a very nice fit on the outside of a 2005 ballnut. I suppose I could easily use the next size up and a threaded sleeve. (I only just found that style, I had been looking at wheel bearings, which also look rather usable, relatively slim, and preload adjustable) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
Andy, I have not seen such an arrangement. The ones I have seen have the nut mounted in a carrier first. Things to consider: Are the OD of the ball nut and the centerline of the ball screw concentric? Some castings are offset to help with mounting the return tubes. Is the OD perfectly round? The bearing that you referenced is a very thin section and would easily distort if the OD of the ball nut was out of round. How are you going to attach a pulley to rotate the ball nut? You should be aware of lubrication issues. A spinning nut tends to expel it own lubricant. The industrial ones I have seen provide for lubricant feed into the carrier holding the ball nut. Steve Stallings -Original Message- From: andy pugh [mailto:bodge...@gmail.com] Sent: Tuesday, December 11, 2012 7:04 AM To: Enhanced Machine Controller (EMC) Subject: [Emc-users] Ballnuts Has anyone ever seen a bearing press-fitted to the outside of a ballnut? I am designing a rotating-nut system, and simply pressing the ballnut into the middle of a double-row angular contact bearing would be very simple. I suppose an alternative would be to look at threading a part of the OD of a flanged ballnut. http://simplybearings.co.uk/shop/p150726/3808B2RSRTVH+Rubber+S ealed+Double+Row+Angular+Contact+Ball+Bearing+40x52x10mm/produ ct_info.html For example looks like a very nice fit on the outside of a 2005 ballnut. I suppose I could easily use the next size up and a threaded sleeve. (I only just found that style, I had been looking at wheel bearings, which also look rather usable, relatively slim, and preload adjustable) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 11 December 2012 14:49, Steve Stallings steve...@newsguy.com wrote: Are the OD of the ball nut and the centerline of the ball screw concentric? Some castings are offset to help with mounting the return tubes. I would hope that the outer diameter was concentric, as no other register is available. Is the OD perfectly round? The bearing that you referenced is a very thin section and would easily distort if the OD of the ball nut was out of round. Again, it would be harder to make it oval than round, so one would rather hope so. How are you going to attach a pulley to rotate the ball nut? Bolted to the flange. You should be aware of lubrication issues. A spinning nut tends to expel it own lubricant. A good point, but one that I will choose to ignore :) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
comment on pulley below -Original Message- From: andy pugh [mailto:bodge...@gmail.com] Sent: Tuesday, December 11, 2012 10:01 AM To: Enhanced Machine Controller (EMC) Subject: Re: [Emc-users] Ballnuts On 11 December 2012 14:49, Steve Stallings steve...@newsguy.com wrote: Are the OD of the ball nut and the centerline of the ball screw concentric? Some castings are offset to help with mounting the return tubes. I would hope that the outer diameter was concentric, as no other register is available. Is the OD perfectly round? The bearing that you referenced is a very thin section and would easily distort if the OD of the ball nut was out of round. Again, it would be harder to make it oval than round, so one would rather hope so. How are you going to attach a pulley to rotate the ball nut? Bolted to the flange. So the ball nut has a flange on one end? Would you need to remove the ball return tubes to press the bearing down the length of the body to get one bearing next to the flange? Guessing here since I do not know what your ball nut looks like. If so, careful of any burrs that may have been raised when the body was machined for the holes associated with the return tubes. You should be aware of lubrication issues. A spinning nut tends to expel it own lubricant. A good point, but one that I will choose to ignore :) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 11 December 2012 15:12, Steve Stallings steve...@newsguy.com wrote: So the ball nut has a flange on one end? Would you need to remove the ball return tubes to press the bearing down the length of the body to get one bearing next to the flange? I will probably use one of these: http://www.zappautomation.co.uk/en/fsud-ballnuts/69-r25-05t4-fsud.html Which appears to be designed to be mounted in a bore. (Pushing the boat out relative to the budget version: http://www.zappautomation.co.uk/en/chinese-brand-ballnuts/185-sfbn2505.html ) I think I will put together models of the three options I am thinking of. I am rather too fond of multiply-concentric designs :-) (And I don't now think that there is any need to rely on a press-fit onto the ballnut, now I found some more bearing types hidden in another part of the website I tend t use) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
A ball nut with an internal ball return would make it easier: http://www.drakeballnut.com/ On Tue, Dec 11, 2012 at 4:03 AM, andy pugh bodge...@gmail.com wrote: Has anyone ever seen a bearing press-fitted to the outside of a ballnut? I am designing a rotating-nut system, and simply pressing the ballnut into the middle of a double-row angular contact bearing would be very simple. I suppose an alternative would be to look at threading a part of the OD of a flanged ballnut. http://simplybearings.co.uk/shop/p150726/3808B2RSRTVH+Rubber+Sealed+Double+Row+Angular+Contact+Ball+Bearing+40x52x10mm/product_info.html For example looks like a very nice fit on the outside of a 2005 ballnut. I suppose I could easily use the next size up and a threaded sleeve. (I only just found that style, I had been looking at wheel bearings, which also look rather usable, relatively slim, and preload adjustable) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Best regards, -- -- Glenn Rapid Converting LLC gl...@rapidconverting.com www.rapidgasket.com -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On Tuesday 11 December 2012 11:47:32 andy pugh did opine: On 11 December 2012 14:49, Steve Stallings steve...@newsguy.com wrote: Are the OD of the ball nut and the centerline of the ball screw concentric? Some castings are offset to help with mounting the return tubes. I would hope that the outer diameter was concentric, as no other register is available. Is the OD perfectly round? The bearing that you referenced is a very thin section and would easily distort if the OD of the ball nut was out of round. Again, it would be harder to make it oval than round, so one would rather hope so. How are you going to attach a pulley to rotate the ball nut? Bolted to the flange. You should be aware of lubrication issues. A spinning nut tends to expel it own lubricant. A good point, but one that I will choose to ignore :) I put zerks into my bearing carriers for the rotating nuts, aligned well enough with a factory hole in the outer race so I can grease mine in the Z drive of my mill, but the spin rate doesn't seem to be high enough to throw it out. I greased them originally, and once since in the 6 or 7 years since I made it. Since I used nooks bronze nuts on 1/2 10tpi acme bolt for the drive nuts, which can be adjusted to near zero backlash by adjusting the top nut a few degrees, keeping a decently clean coat of grease on the bolt is a larger concern. It is exposed to the elements although not directly dirtied by swarf as its above the head sled casting on that toy. Cheers, Gene -- There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) My web page: http://coyoteden.dyndns-free.com:85/gene is up! All God's children are not beautiful. Most of God's children are, in fact, barely presentable. -- Fran Lebowitz, Metropolitan Life I was taught to respect my elders, but its getting harder and harder to find any... -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
Andy, I would be surprised if you could do what you describe.. since the ballnut is likely hardened so unless you grind it, altering the OD will not be easy. The ID of the bearing is obviously hardened as well. What are the chances that you will have the proper dimensions for a light press fit? Do you play the lottery? ;-) Dave On 12/11/2012 10:46 AM, andy pugh wrote: On 11 December 2012 15:12, Steve Stallingssteve...@newsguy.com wrote: So the ball nut has a flange on one end? Would you need to remove the ball return tubes to press the bearing down the length of the body to get one bearing next to the flange? I will probably use one of these: http://www.zappautomation.co.uk/en/fsud-ballnuts/69-r25-05t4-fsud.html Which appears to be designed to be mounted in a bore. (Pushing the boat out relative to the budget version: http://www.zappautomation.co.uk/en/chinese-brand-ballnuts/185-sfbn2505.html ) I think I will put together models of the three options I am thinking of. I am rather too fond of multiply-concentric designs :-) (And I don't now think that there is any need to rely on a press-fit onto the ballnut, now I found some more bearing types hidden in another part of the website I tend t use) -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
Andy, everything is a dough (as one of the elder workers in my shop used to say), meaning: be aware of the expansion of the inner race of the bearing by pressing things in! Peter andy pugh schrieb: Has anyone ever seen a bearing press-fitted to the outside of a ballnut? I am designing a rotating-nut system, and simply pressing the ballnut into the middle of a double-row angular contact bearing would be very simple. I suppose an alternative would be to look at threading a part of the OD of a flanged ballnut. http://simplybearings.co.uk/shop/p150726/3808B2RSRTVH+Rubber+Sealed+Double+Row+Angular+Contact+Ball+Bearing+40x52x10mm/product_info.html For example looks like a very nice fit on the outside of a 2005 ballnut. I suppose I could easily use the next size up and a threaded sleeve. (I only just found that style, I had been looking at wheel bearings, which also look rather usable, relatively slim, and preload adjustable) -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Ballnuts
On 11 December 2012 17:11, Dave e...@dc9.tzo.com wrote: What are the chances that you will have the proper dimensions for a light press fit? The Nut is g6 according to the catalogue, that gives me somewhere between 3um interference or 25um clearance. So glue would probably be needed. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] Ballnuts
On 11 December 2012 17:48, Glenn Edwards gl...@rapidconverting.com wrote: A ball nut with an internal ball return would make it easier: http://www.drakeballnut.com/ Novel. I see you couldn't use a plain tube as a ball retainer if you wanted to remove the nut. Roland -- LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
