At 09:45 AM 3/25/2010, you wrote: >Mark Wendt (Contractor) wrote: > > [snip] ><more snippage> > >> > > Steve, > > > > It doesn't seem to matter where along the length of the rack the > > gantry is, it happens whether it's in the middle of the rack or at > > either end (the rack is 6' long). > > > > The pinion diameter is 1", according to the maker of the R&P > > setup, and when I measured the OD of the pinion it was slightly > > larger than 1" which makes sense if the pitch diameter is 1". Works > > out pretty easy in my case since with a 1" pitch diameter, the pinion > > moves 3.14159 per revoultion. Microstepping was set to 8, gearing is > > 3:1 reduction, and if I remember right there was a scale of somewhere > > around 1579.xxxxx or something close. > > >OK, 1527.xxx is what you'd get there. The thing is, microsteps don't >really increase your resolution, they're mostly there to prevent >resonance. The number of real steps you have, where the motor has full >torque, is 190.985/inch. That translates to a 0.005-ish step size. I >think that might also explain the 0.001 moves - nothing happens until >you get to the next full step (or close enough that it's the closer >one), when the motor then clicks over to that full step position. > >- Steve
Yeah, I knew it was close to somewhere around 1500 something. So, based on the 190.985, that would cause resolution problems at .1" moves too? Guessing that the only way to fix this then would be to use a different pulley then - I'd either have to go at least 1/2 the size on the stepper pulley or double the pinion pulley to get enough resolution? Or change the pinion size, correct? (In reality, I'm pretty much stuck with changing out the stepper pulley, because the pinion/pulley assembly is a machined unit). Mark ------------------------------------------------------------------------------ Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
