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?


  • 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?


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):