Stepper Motor Noise

Hi, Just got my CNC put together and getting to know it. My motors (Y motors) are make a strange noise when they are at idle. It’s not quite humming but more like a fly buzzing in the window trying to get out. Is that normal? I have another CNC and the motors are dead silent. Thanks. Jeff

1 Like

Mine as well. Just got to put together my Journeyman and get a high pitch noise while idling.
Can someone give us a clue on why that may happen?

I don’t know the full answer, but I think it has something to do with the idle current frequency being in the audible range. Whenever the controller is powered up, the stepper motors are fully energized, even when idle. FAQ: What is stepper drive idle-current reduction and why does it help?

Even though my other CNC doesn’t make the noise the folks at OF told me the noise is normal. The motors still make the noise but after nearly a year the CNC runs fine. No issues at all and I guess I do not notice the noise much like I did at first.

It’s idle (holding) current. It’s normal.