Filament Failing to Reach Extruder Motor from MMU
I just finished setting up the MMU2 upgrade on my Prusa MK3. While I was able to get it to perform the first layer calibration I am having issues with at least two of the five filament feeds. For some of the feeds the filament seems to get caught at the end of the fitting right before entering the extruder.
I've tried going into the MMU settings and set the initial load distance, but the filament doesn't move when I do so. Examining the MMU feeder, the pulley is rotating, but doesn't seem to be moving the selected filament. Pulling the filament out, where the filament is getting stuck at the pulley, I am seeing damage dealt to the filament as it appears that the pulls is grinding down the filament.
Here is an example of the damaged filament that I pulled out.
On feeds 1, 3, and 5 I was able to get some filament to load with some issues, but a pair of the pulley gears are no longer loading filament. I'm not certain if it is because they might be damaged or dirty from running against the filament or
Are there any suggestions on how I can fix this or something else I could to help diagnose this?
Thank you
RE: Filament Failing to Reach Extruder Motor from MMU
I had a bit of an issue where filament couldn't get through the idler because I'd tightened it too much. That meant that the filament was jammed, and it was ground down like in your picture. So much filament "dust" was collected in the gear that it could barely work after that. I used one of the Prusa acupuncture needles to clean it out.. I loosened the idler, and all was good after that (in that particular regard).