MakerGear Forum

Hi All,

After a series of mishaps (HPB wire melted the board connectors, E0 motor driver died, surface mount fuse blown) and a lengthy patient string of tech support emails with Josh, that prince, I have a working M2 again. However, now after this series of events, all the steppers are making a high pitched wine. I remember this from running a first gen Cupcake for a few years, and I recall the solution being adjusting the current going to the steppers with a little trim pot. On the RAMBo boards, I understand this value is digitally controlled, maybe in the configuration.h tab?

Does anyone know why this noise might be happening, and what the range of current values I can get away with tweaking is?


Also, on a side note, what's the GCODE command to override the motor timeout. I'm sure there must be one.

Configuration_adv.h line 250 or thereabouts. DIGIPOT_MOTOR_CURRENT

M85 S0

telephone1652 wrote:Does anyone know why this noise might be happening

Alas, that whine is inherent in the nature of microstepping motor drivers: you're hearing mechanical resonances pumped by the high-frequency pulses that regulate the motor current. The volume depends on the current, but reducing the current also reduces the motor torque, which causes far more problems than it cures.

You could dial in lower motor currents on a Cupcake, because its highest speed wasn't all that high and (apart from the monster Z stage) didn't require much torque. The M2 operates in a much higher performance realm.

For males, the simplest and most straightforward solution is to wait a few decades, while your hearing deteriorates to the point where you can't hear those annoying frequencies... [sigh]

the GCODE command to override the motor timeout

M84 and M85 are your friends...

Thanks, fellas.

telephone1652 wrote:Thanks, fellas.

Is it this sound? https://www.youtube.com/watch?v=mDeutN9CcpE

For me, the belt was too tight.