Much better with this morning’s test. I milled a the same small part out of some moderately hard wood. No false limit alarm and I had dropped the Z axis max speed and acceleration back to what I had with my old stepper. I have some room to push the current limit up on the Z Axis and since the motor is still staying quite cool compared to the old stepper I think that I’ll push it up to gain some more torque, then I’ll repeat my test taking the Z speed and acceleration back up at least a little bit.
I thought that I might have an issue with the X and Y but double checked the gcode and it was just that the gcode was slightly offset from 0,0 to allow for adding support tabs to the piece. So other than the fact that I could probably use more torque on the X and Y it’s looking pretty good at the moment.
BTW in one of the posts here you had posted the code for the Z torture test. A couple of the lines of gcode are missing the “F” for the feed rate. With GRBL at least this caused some interesting moments as the tool was trying to go to -3522. Here’s one of the lines from the post:
G1 Z-3 522 should be G1 Z-3 F522 There is another further down.
Maybe this works OK with the RAMPS Marlin firmware? But with GRBL it ignores the space and treats it as a relative move to -3522. Just thought I’d mention it.
Running a test with .4mm step down but leaving my slower Z Axis firmware configuration for this one.