On Tuesday 25 August 2015 19:57:24 Tom Easterday wrote: > I was working on some issues with the lathe today and discovered that > what I thought was a 1:1 relationship between the pulley on my spindle > motor and pulley on the spindle head - is not. The diameter of the > spindle pulley is 4.2125” while the spindle itself is 5.175” (they are > probably actually 107mm and 130mm or thereabouts). This give a 0.833 > ratio and explains why 3500rpm is actually spinning at about 3000rpm > according to my tach. I am wondering the best way to let Linuxcnc > know that this is the case so that commanding 3000 gives me 3000. > > -Tom
I can't help you, Tom, other than to say that the revs commanded vs revs obtained seem to be rather arbitrary on both my lathe and my new mill. If there is a general "rule of thumb" for setting the PWMGEN SCALE, (and other stuff in the signal chain between the spindle PID and the pwmgen input, it would be helpful to me if someone either wrote the tome that explains that, or perhaps supplies a link to an already valid method to contain the madness. I have something that does approximately what I ask, but it was turning knobs in the dark for sure. 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> ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
