Microsteps and motor current

[aguinaldoabbj]

Congrats @JoeTodes on this great achievement on such a cheap printer.

I've recently installed Klipper on my Biqu B1, the learning curve is a bit slow, but i'm making progress.
I checked out your printer.cfg, It caught my attention that you are using 128 microsteps for your xy stepper motors. This differs from absolutely all other examples I could find regarding Biqu B1 with Klipper. Why is that? Are you using the default stepper motors?

How about the current applied to the motors? How did you get to thus 1.2A ?

Thanks in advance.

[JoeTodes]

I can't remember now why I went with 128 microsteps but it's been working fine. For current, because I wanted to push the machine to the fastest I could, I looked up the max rated current of the stepper drivers (which I think is actually something even higher IIRC) and found a value around there that didn't overheat the motors. 1.2A seems stable for me but your mileage may vary with the variability of individual motors, ambient room temperature, airflow, etc.

[aguinaldoabbj]

I can't remember now why I went with 128 microsteps but it's been working fine. For current, because I wanted to push the machine to the fastest I could, I looked up the max rated current of the stepper drivers (which I think is actually something even higher IIRC) and found a value around there that didn't overheat the motors. 1.2A seems stable for me but your mileage may vary with the variability of individual motors, ambient room temperature, airflow, etc.

Thanx @JoeTodes. If I go this fast on mine, I can hear very annoying squeaky and high pitch noise coming mainly from the Y axis (bed). Is this current increase going to lower the noise?

[M1k1m40]

For more information about this matther in TMC2208 read:
https://www.klipper3d.org/TMC_Drivers.html
Section:
Setting "spreadCycle" vs "stealthChop" Mode and TMC interpolate setting introduces small position deviation
You have to choose desviation or noise.
However I use 0.8A for the motor becouse with 1.2A motor too hot.
Joe decide spreadcycle, interpolate, steps 164. I'm too noob to give an opinion yet.
Thanx @JoeTodes.