MMU2s extruder stepper doesn't turn during print
TL;DR: this seems similar to https://github.com/prusa3d/Prusa-Firmware/issues/1377 but the stepper motors act fine immediately before and after the print is attempted.
The problem: The MMU2s "extruder" stepper doesn't turn while the print is in progress. However, it does turn as expected via the "load to nozzle" menu option, when loading the filament to the nozzle at the start of the multi-material print and when unloading when the print is stopped manually. Additionally, the extruder stepper functioned well enough to print about half of the dual color benchy gcode that was included in the sample files before failing for unrelated reasons (the filament broke in the buffer and I didn't realize that until I stopped the print).
Short video of this happening:
Setup:
- MK3s (kit, upgraded from MK3 which worked pretty much flawlessly since last June), firmware version 3.7.0
- MMU2s, firmware version 1.0.5
- Amazon Basics brand PLA
Troubleshooting steps:
- Updated firmware
- Reset MMU memory
- Unplugged/replugged all MMU cables, including the ones inside the einsy case
- Checked bondtech gear alignment and screw tightness
- Sliced the dual color benchy myself
RE: MMU2s extruder stepper doesn't turn during print
Good morning Matthew,
the mmu2 only transports the filament during filament load, and filament unload, once the filament reaches the extruder bondtech gears, they take over the filament drive, the selector drum in the mmu2 moves the pressure roller out of the way, and the mmu2 hobbed gear shaft motor stops rotating...
so it sounds like your mmu2 is working correctly
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK