JUs for some background: how is the motor connected to the spindle? Is it V-belts, cog belts, or gears?
V-belts would cause me to think twice due to possible slippage introducing error. Ray --J. Ray Mitchell Jr. jrmitche...@gmail.com The dogmas of the quiet past, are inadequate to the stormy present. The occasion is piled high with difficulty, and we must rise with the occasion. As our case is new, so we must think anew and act anew. We must disenthrall ourselves, and then we shall save our country.*Abraham Lincoln <http://www.quotationspage.com/quotes/Abraham_Lincoln/>*, *Annual message to Congress, December 1, 1862* *16th president of US (1809 - 1865)* On Fri, Nov 24, 2017 at 8:49 AM, Gene Heskett <ghesk...@shentel.net> wrote: > On Friday 24 November 2017 11:04:16 Peter C. Wallace wrote: > > > Why dont you just make an index mark/pointer on the headstock and > > chuck This should be hand settable to less than a degree of chuck > > motion then just note the motor encoder count when the chuck is > > aligned with the mark and then rotate the motor until the chuck has > > turned say 20 turns. This should give you the ratio to within 1/7200 > > which should be better than needed. if thats not enough, just do more > > turns, you could get to PPM accuracy is less time than it takes to > > futz with doing this is hal > > > > Peter Wallace > > Mesa Electronics > > > That might be one way, Peter, and likely less time. But accessing the > motor shaft is going to be difficult, perhaps with pliers on the encoder > coupling. A bent wire in the chuck to use as a pointer. And running the > motor very slowly until that 20th is about to come up would greatly > simplicate that. Then just subtract the first raw-count from the last. > > Better yet would be a counter on the index and just let it run a while. > Then the question is how can I do that. I'll figure out something. That > is what gpio's are for... > > But first, transfer the wiring... > > ---------------------------------------------------------------------- > >-------- Check out the vibrant tech community on one of the world's > > most engaging tech sites, Slashdot.org! http://sdm.link/slashdot > > _______________________________________________ > > 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) > Genes Web page <http://geneslinuxbox.net:6309/gene> > > ------------------------------------------------------------ > ------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
