Extruder Stepper Very Hot
Anyone else notice the extruder stepper on the MK3 getting very hot, at least compared to the MK2S? I imagine it has to work harder at the MK3 speeds but I was quite surprised by how hot it was getting. I'm assuming it's doing what it needs to current wise since that is all automatically controlled. Just curious.
Re: Extruder Stepper Very Hot
Mine runs very hot too.
I don't think current is regulated automatically. I looked in in the firmware sources and found the extruder motor current is set to 35.
//new settings is possible for vsense = 1, running current value > 31 set vsense to zero and shift both currents by 1 bit right (Z axis only)
#define TMC2130_CURRENTS_H {13, 20, 20, 35} // default holding currents for all axes
#define TMC2130_CURRENTS_R {13, 20, 20, 35} // default running currents for all axes
Coolstep (Trinamic autoamtic current scaling) does not seem to be used.
I don't know if my calculations are right, but with Rsense = 0.22Ω, Vsense = 0, 35 >> 1 = 17, extruder current would be about (17+1)/32*0.96A = 540mA.
Re: Extruder Stepper Very Hot
If you're using Linear Advance (which is enabled by default in the MK3 profile of Slic3r), the extruder motor has to work harder and will get warmer, but it's still well within the recommended working temperature.