Use a cylinder square: https://www.ebay.com/i/312037924818?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=312037924818&targetid=541454015492&device=c&mktype=pla&googleloc=1014782&poi=&campaignid=6470552628&mkgroupid=81274342767&rlsatarget=aud-762207186714:pla-541454015492&abcId=1139336&merchantid=8120224&gclid=Cj0KCQiAt_PuBRDcARIsAMNlBdr9GnvyFwQqV15dYDNLYJa-MSmhDV7Y65Gp7GAnQkUOOGJ9CgQ9-2gaAn4hEALw_wcB
Ken Kenneth Lerman 55 Main Street Newtown, CT 06470 On Sun, Nov 24, 2019 at 9:35 PM Gene Heskett <ghesk...@shentel.net> wrote: > On Sunday 24 November 2019 20:54:11 Stuart Stevenson wrote: > > > I have used bidirectional compensation on several machines. The latest > > on a cinci just like the blue one at MPM. It has a Cin950 control. I > > collected data using a CMM connected to the X table. I put the data in > > the file, restarted the machine and the machine had twice the error as > > when I started. I reversed the data in the compensation table and > > voila the machine looked pretty good. Repeated for Y and Z. > > Collecting data for 3 dimensional correction may be problematic in > > some cases. > > > Nearly impossible in the case of a lathe, which generally has no facility > other that the stops of a QCTP to set tool height. Which is exactly why > I treated the sheldons bed wear which has the effect of both tilting the > carriage and allowing it to sink, as x errors only. And it seems to > have worked fairly well. > > But I'm thinking in terms 3 axis for my G0704 and its crooked post. Its > either a lot of time scraping, or a 3D COMP but how does one actually go > about measuring it. Lumberyard squares which everybody has a dozen of > will never give accurate enough results. likely aren't going to be that > true to each other. > > > thanks > > Stuart > > > > On Sun, Nov 24, 2019 at 7:26 PM Gene Heskett <ghesk...@shentel.net> > wrote: > > > On Sunday 24 November 2019 19:47:33 Stuart Stevenson wrote: > > > > A two (or three) dimension comp file could work wonders to > > > > straighten the motion. To be able to correct Y and Z motion per X > > > > motion at the same discreet points chosen for the bidirectional > > > > compensation would be a very good thing. Correcting X and Z for Y > > > > motion and correcting X and Y for Z motion would complete the > > > > package. > > > > The interpolation for the correction values would make a machine > > > > motion much straighter. > > > > > > > > This would not perfect the machine as lead screw lost motion and > > > > gib/linear (guide ways) slop would still be present until > > > > mechanically corrected. > > > > > > > > A slight warp in the bed of a lathe would be easily corrected. > > > > > > Ok, but lets pull this magic rabbit back out of the weeds. Where > > > might I find a good tut on actually putting it to work? > > > > > > Thanks Stuart, Gene. > > > > > > 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> > > > > > > > > > _______________________________________________ > > > Emc-developers mailing list > > > Emc-developers@lists.sourceforge.net > > > https://lists.sourceforge.net/lists/listinfo/emc-developers > > > 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> > > > _______________________________________________ > Emc-developers mailing list > Emc-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-developers > _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
