Extruder motor won't turn at low temperature

K8200 3D Printer
1

Greetings.
I added a second stepper motor just for testing (for a specialized project). With quick disconnect connectors I can shift power from the real extruder motor to a different motor resting on a table. The goal is to use the power normally supplied to the extruder motor, but I do not want to heat up the true extruder nozzle (which I normally set to 190C for PLA filament) since the true extruder motor is not even receiving power. Power instead is going to my second stepper motor. I set printer settings in the Repetier to a low temperature value and have edited the gcode to wait for this low temperature value. Failure. Second motor does not respond. However if I really do set everything (gcode, printer settings) to Textruder=190, the secondary motor does turn as commanded. Hmmm. My Hypothesis: There is something in the settings or firmware that says “Do not turn power on to the extruder motor unless the temperature is high enough to melt PLA.” This would make some sense as turning an extruder motor without melting the PLA would be like holdiing down the brakes of a race car.

Essence of question: How do I supply power to the extruder motor even at low extruder temperatures.

Thank You.

2

Greetings again.
I managed to determine a solution.
Very little needs to be done to perform “cold extrusion.”
In the gcode, simply insert
M302 S0 ; This turns off all temperature control.
Additionally, I commented out (with :wink: the M190 S50 and the M109 S190
commands which are wait commands for the heating bed and hotend to reach their normal printing temperature.

But be careful. Do not try this with an extruder loaded with filament.
You cannot extrude cold filament.

Happy upcoming holidays