It would technically still have thrust bearings, no? But on the nut instead of on the screw. I’m not sure this changes anything.
> On Apr 12, 2021, at 3:55 PM, Gene Heskett <ghesk...@shentel.net> wrote: > > On Monday 12 April 2021 14:55:18 Ralph Stirling wrote: > >> Thrust bearings at the ball screw ends perhaps? >> > You may want to read it again Ralph, the screw is fixed, with a rotating > nut. > > I had one like that I built once. I think Todd is correct and the screw > needs to go to a rebuilder. With the nut still on it because they may > have to work on both. My $0.02 of coarse. >> -- Ralph >> ________________________________________ >> From: Todd Zuercher [to...@pgrahamdunn.com] >> Sent: Monday, April 12, 2021 7:48 AM >> To: Enhanced Machine Controller (EMC) >> Subject: [Emc-users] Worn Ball Screw? >> >> CAUTION: This email originated from outside the Walla Walla University >> email system. >> >> >> Those here who have had to deal with a worn out ball screw. How is >> this normally manifested. I have a machine that is only showing >> backlash under load. Is that normally how a worn out screw shows it's >> age? I was expecting it to be normal loose backlash that you can >> measure. But this is showing up as springy softness that you have to >> give a pretty hard shove against to move the dial indicator, then it >> snaps back to zero when you let go. Using the usual jogging methods >> to read backlash, the machine reads zero backlash and positions well. >> But dynamically it is awful, with loud clucking noises on direction >> changes and horribly wavy marks left on the pieces milled at those >> changes. Giving a shove on the table, I can measure more than >> +/-0.01" of this "springy" backlash, but moving the screw to a >> normally unused position I can only measure about 0.001". This is a >> big fixed screw (about 2" diameter and more than 14ft long) with >> rotating nut, is there any hope of fixing it? I'm considering trying >> to send the screw out to one of those screw refurbishing places. The >> machine manufacturer quoted us over $18,000 to replace it. >> >> Todd Zuercher >> P. Graham Dunn >> Inc.<https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2F >> www.pgrahamdunn.com%2Findex.php&data=04%7C01%7Cralph.stirling%40wal >> lawalla.edu%7C58338609df8b45b6914308d8fde00b00%7Cd958f048e43142779c8deb >> fb75e7aa64%7C0%7C0%7C637538485997249904%7CUnknown%7CTWFpbGZsb3d8eyJWIjo >> iMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000& >> sdata=Ld9xm92SAMAjLkMiiIF8IUVaEr%2FNPwfF0CkiXtceb3E%3D&reserved=0> >> 630 Henry Street >> Dalton, Ohio 44618 >> Phone: (330)828-2105ext. 2031 >> >> >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Flist >> s.sourceforge.net%2Flists%2Flistinfo%2Femc-users&data=04%7C01%7Cral >> ph.stirling%40wallawalla.edu%7C58338609df8b45b6914308d8fde00b00%7Cd958f >> 048e43142779c8debfb75e7aa64%7C0%7C0%7C637538485997249904%7CUnknown%7CTW >> FpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6M >> n0%3D%7C1000&sdata=IkA489PPWpVFBGtsJze2eyUhLWfAKYR3Lw2k0frRhLc%3D&a >> mp;reserved=0 >> >> >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users > > > 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) > If we desire respect for the law, we must first make the law respectable. > - Louis D. Brandeis > Genes Web page <http://geneslinuxbox.net:6309/gene > <http://geneslinuxbox.net:6309/gene>> > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net <mailto:Emc-users@lists.sourceforge.net> > https://lists.sourceforge.net/lists/listinfo/emc-users > <https://lists.sourceforge.net/lists/listinfo/emc-users> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
