@infiniteloop I hadn't thought of that, I will try a fresh nozzle and upgrade the fan, thanks for the suggestion

@elmoret This problem started while printing ABS but I have since reverted to testing with PLA with the same results, the motor keeps stalling after 15-20 minutes of printing when coming from a cold start and sooner on later prints.

@Notepad I have also tested with the absolute max current E3D recomends, 0.6A peak with the same result, I think anything beyond that might risk damaging the coils.

I will open a case with E3D to be sure the motor is not damaged at this point.

For anyone following.

I just measured the coils resistance in "hope" for them to be out of spec but they are not. Both measured 7.6 ohms at room temperature.

I haven't been able to print ABS nor PLA. I will keep trying tweaking the configuration but I feel that I have tried everything.

@dc42 the Duet3 control board is not installed inside the closed chamber as the roto toolboard is. How can this calibration affect the outcome of the printing tests?

Is there anything off in the M69 P121.0 report?

@dc42 these are the current settings:

M569 P121.0
Driver 121.0 runs forwards, active low enable, mode spreadCycle, ccr 0x00053, toff 3, tblank 0, hstart/hend/hdec 5/0/0, pos 8

@dc42 I sent the command as soon as I realized it was failing, 2minutes difference top, at that point I hadn't enabled anything related to stall detection.

Quick update of my tests:

• Disconnected the Roto motor from the Roto toolboard and rewired it to use a Duet3 stepper driver - Still failing
• Printed the exact same test print but now with PLA hoping that the ABS ambient temperature was the trigger of the motor failure but it also failed
• Inspected the whole motor assembly but found no issues apart from maybe insufficient grease on the gears (waiting for the grease to test)

At this point I'm almost sure the motor or some configuration is the problem but I can't find the root cause of it

I haven't been able to conrrectly configure stall detection for the extruder, I just found this post from some years ago https://forum.duet3d.com/post/102570 so I'm running out of options if CoolStep can't be implemented...

@dc42 I've been reading about CoolStep and I think it is the next step, unless you have another idea for me to try before.

Are there any special considerations when implementing CoolStep for the extruder? Most of the documentation is oriented for the other motors

@dc42 Understood. I did the test grounding the metal body of the Roto through a wire soldered to the V- terminal of the power connector in the toolboard with a 100k serial resistor but it didn't work, it failed just like before even without reaching 70C

@dc42 My bad, there is no connection between them as the way I created the fan shroud requires the mounting screw not touching the toolboard but instead coming from the shroud. I have now read the wiring notes from the docs and will be trying it.

How can this cascade to a motor stall?