On Monday, April 16, 2012 05:18:47 AM Gary P. Fiber did opine: > I need to find the start of this thread. i am running a G540, an Intel > M525MW board
Other than both of mine are D525MW's > with Probotix steppers motors and all 3 axes move fine. I > just need to calibrate them for proper distance and get the homing Hall > effect sensors connected.I am not running the charge pump enabled in the > G540. Am I missing something? > > Gary K8IZ Probably not Gary, but that should probably be qualified by writing a loop that starts and ends 20 thou into a dial indicator and runs back and forth 2 or 3" a few hundred times, to check for missing pulses, too short a setup and hold times on direction reversals and such in the stepper pulse generation. Obviously it should end at the same location it started at. Because of backlash, I'd throw away the first run, re-zero the indicator and use the second runs results. As for scaling that should be nothing but math. For instance the motor needs 200 full steps to make one turn, and your drivers are set to do 8 microsteps 200x8=1600 Then the motor is geared down so it makes 2 revs to turn the screw one rev so 1600x2=3200 Then the screw is 16 tpi, so it takes 16 turns to move an inch. 3200x16=51200 and that becomes the scale factor for that axis in your .ini file. Metric machines running in the millimeter mode should divide that by the usual inch to mm conversion: 51200/25.4=2015.7480315. Floating point is fine there. That may well be more accurate than your screws. My cheap OEM Z screw, moving .10000" at a time, has places where either it, or the dial indicator, are off by 2 or 3 thou, so I may have to either map it, or put decent ball screws in it. Bring $ in little red wagons, I am trying to make a poor mans silk purse out of a 7x12, so I am not expecting micron results most of the time. So my first attempt at mapping will be to prove the indicator, its a $60 Grizzly. Say no more. :( Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> Absence makes the heart grow fonder. -- Sextus Aurelius ------------------------------------------------------------------------------ For Developers, A Lot Can Happen In A Second. Boundary is the first to Know...and Tell You. Monitor Your Applications in Ultra-Fine Resolution. Try it FREE! http://p.sf.net/sfu/Boundary-d2dvs2 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
