On Tuesday 05 July 2016 09:49:08 Leonardo Marsaglia wrote: > 2016-07-05 9:34 GMT-03:00 Rick Lair <[email protected]>: > > I have been having a problem on another one of our turning centers > > where the x axis will "twitch", for lack of a better word, at random > > times while moving down ( slant bed, back tool lathe). I have > > checked all couplings between the encoder and ball screw, checked > > the synchronous belt tension between the ball screw and the servo, I > > just replaced the encoder, and I still cannot figure out what my be > > causing this. It is not every time it is moving, and it is not in > > the same place every time when it does happen. Could there be > > something funky going on in the servo? I was thinking if I had a > > storage oscilloscope I could what the motor voltage to see what that > > is doing, but I don't have one of those, but have flirted with > > buying one in the past. > > > > Any thoughts as to what would cause this? > > Hello Rick. > > Not an expert on this list but, could it be this is is happening > because you have the gibs of the joint a little loose? Since it's only > happening while moving down it's more than a possibility. > > Off course this could only affect the movement of the joint no more > than the backlash of the screw, in fact if you have this problem with > the gibs it's time to check also the backlash too.
This sounds odd, but I found my table, with the gibs set for easy motion but couldn't feel any slop when I grabbed the end and tried to rotate it, would at times move on the oil film with no ground contact for 2 or 3 inches at a time. I debated putting a ground on the table but snugged the gibs instead. I mention it only because the motor driving the table is generally mounted solid to the table. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Attend Shape: An AT&T Tech Expo July 15-16. Meet us at AT&T Park in San Francisco, CA to explore cutting-edge tech and listen to tech luminaries present their vision of the future. This family event has something for everyone, including kids. Get more information and register today. http://sdm.link/attshape _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
