Underextrusion/unloading issues
The problem:
My newly arrived mini is exhibiting an unfortunate tendency to under-extrude. Even when slowed down to 30% speed during prints, I can still hear the hobbed gear skipping a few times each layer. When I attempt to unload filament, the end will catch at the beginning of the PTFE tube and won't go further proceeding to grind the filament. From partial disassemblies, the culprit appears to the be the brass fitting squeezing the PTFE tube too tightly on the extruder end.
Potential solutions:
Loosening the tensioning bolt. I have gone both directions to no avail thus fair, bu perhaps I just haven't found the magic number yet
Get some abrasive filament to ream out the tube more. I'd just rather not ream out the all-brass hotend nozzle at the same time.
Replace fittings with Festos so that it's at least earier to clear jams.
I'd be curious to hear the thoughts of the collected wisdom of the forum.
RE: Underextrusion/unloading issues
I've had similar problems, filament stops extruding after a few layers and then starts grinding the filament to dust.
And then, my lcd knob siezed and refused to rotate.
I'm currently waiting for my new lcd to arrive and then it'll be back to trying to get this thing to print.
RE: Underextrusion/unloading issues
I too have had filament get stuck and grind away. Had to remove by dismantling the PTFE tube then force out the jammed section. Then my LCD knob seized. I have to wait ten days until the replacement LCD gets here.