At 09:01 AM 3/25/2010, you wrote: >Mark Wendt (Contractor) pravi: > > At 08:43 AM 3/25/2010, you wrote: > > > >> Mark Wendt (Contractor) pravi: > >> > >>> At > >>> .001, sometimes I'd get no movement (I'd here stepper motor noise but > >>> no movement on the dial indicator), other times I'd get a half-thou, > >>> > >>> > >> This can be only mechanical then... Check backlash and endplay of nut... > >> check coupler too.. If motor make step and gantry not then don't blew > >> software :D > >> > >> Slavko. > >> > > > > > > This is on a rack and pinion system, pulley mounted directly on > > stepper, pinion has pulley mounted directly to it, with cogged timing > > belt driving the pinion. All these numbers were with the gantry > > moving in one direction, jog and hold, jog and hold, while watching > > the dial indicator for movement between jogs, which there was > > none. Does backlash come into play when all moves are in the > same direction? > > > > Mark > > > > > > >If you use microstepping then you can just need to much.. Anything above >8th is wasted. Regular steppers doesn't make same steps with microstepping. >Backlash can deflect measurment even if you move in same direction. >Seems silly but it's true. >If you tend to stop gantry to fast then stored kinetic energy in gantry >move "slash" and voila.
I'm pretty sure I've got the machine set up to 1/8 micro step now. I tried doing this at different jog and acceleration speeds and still saw the same discrepancies. 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
