Z Axis Upgrade W/ 269oz NEMA 23 Stepper

I just upgraded my Z axis to a direct drive design with a 269oz NEMA 23 stepping motor.

Everything seems to be working well except the sound of the new motor is rather harsh and not smooth like the others. It’s a grinding sort of sound even though nothing is grinding. It’s just the sound coming from the motor.

Would changing the micro step switch settings in the X Controller along with maybe some axis specific GRBL settings help make this new stepper run more smoothly?

Yes.

  • First recalibrate your $102 GRBL parameter
  • Increase your $112 and $122 setting as you now have a more powerful drive chain, the default values for Z is low.
  • Then reduce microstep setting on the Xcontroller Z-axis until you feel it run smooth. The harsh sound is most present during slow speeds/acceleration/retardation

I did the same upgrades and it was super loud. As mentioned you need to adjust your microstep for the Z-Axis which is done on the xcontroller using dip switches. I believe I changed mine to 1/4 from 1/8 so I also had to double my value for $102. It is barely audible now. I believe it is from some sound resonance causing vibrations at certain speeds.

It is. The mechanical connection is rigid so each step start/stop is “seen” by the assembly and this makes it vibrate.
Smaller steps mitigate this phenomenon. So will faster acceleration values / rapids also as it lessen the time spent at slow movement.

Imagine the feed is like 3mm / min, each step will have time to initiate and terminate motion before next step occur, causes a “jagged” motion.

I just installed the super grade direct drive z-axis and 269oz motor from tbdcnc and am having the exact same issue. Would you mind providing a little more detail On what exactly to change as it relates to the potentiometers and microstepping switches?

Gshield or Xcontroller?

X-Controller

First of all, you wouldnt need to change the potmeters as they are set to an appropriate current limit as-is.
The microstepping switches, if you feel the current value give you rough running, increase untill it run smoothtly.
A recalibration of $102 bay be needed.

Start with step 1, prepare controller board (Set all three switch #4 to OFF while you are at it):
http://x-carve-instructions.inventables.com/750mm/step8/