I bought a used MPCNC a few weeks ago and am just now trying to get it up and operational.
I’ve got an issue with the z-axis stepper motor or driver. When I use the LCD or Repetier to manually move all axis move properly and the proper amount IE: distance. The trouble is when I send a print the z-axis motor spins all of a sudden and seems to stall or snag thus getting out of alignment. Here is a video showing the behavior: www(dot) dropbox (dot) com/s/9d9zhxya3zbofkm/z-axis.mov?dl=0 Can someone help me troubleshoot this? Is it a hardware issue, assembly issue, or software issue. If the z movement during the LCD or manual movement is working fine can’t I just set that “rpm” or speed in the driver somewhere? TIA
P.S. I’m just getting started so the machine is not organized and the wiring is haphazard. Once I get things working properly I’ll get cable chain rails etc.
You have the allthread Z. Which is very sensitive to Z speeds. A leadscrew is about 4x fewer steps/mm.
You got it nailed on the head that too fast Z is causing lower torque. We usually recommend fixing it in cam, but I am happy to hear the firmware fixed it. It didn’t used to. What controller and marlin version are you using?
A 24V power supply would help too, giving you a higher speed range with full torque. But not all controllers and accessories can handle that.
In Estlcam, and I think in fusion, you can tell it to add a speed to every move and to limit the Z speeds. Otherwise, you might be doing an XY move at 15mm/s and then lose steps when you try to drive Z at 15mm/s.
