Re: Measuring backlash more accurately?

At 11:24 PM 2/16/03 -0600, Jon Elson wrote:

>You might make sure the steppulse polarity is going the right
>way for these drivers, too.

I think you nailed it, Jon. I had not even paid attention to the pulse
polarity. But near the back of the 29A55 brochure, it says "The step
occurs on the rising edge of this signal." CNCPro was set "High-to-Low" as
it was, and I flipped it to "Low-to-High" and the anomalous behavior seems
to have stopped. When I cycle back and forth, there is no accumulation of
movement now whether I have the backlash set at .0008, .001 or .0011. I
will leave the compensation on all axes as I had originally measured it
(.002X, .001Y and .002Z) and try my contouring program again tomorrow.

I wonder if that has been the source of my "drifting" all along?!? Thanks
for your insight, Jon! At least I now have a *very* carefully wired
controller box... :-)

Best regards,

Randy

Randy Gordon-Gilmore ,----.___________ ______________ _________________
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