MP Select Mini Extruder Knob

thingiverse

I had to get around the fact that I couldn't visually tell when filament was being sucked into the extruder, so I came up with this little knob. It serves two purposes: as a visual indicator of the extruder's suction and as a way to manually feed in or pull out filament. What really gets me is being able to see that the extruder is running. It's a pretty tight fit, and I made it that tight on purpose. It shouldn't need any glue at all. I simply jammed the part onto the extruder motor shaft as far as I could with my bare hands, then gave it a few taps with a heavy object to get it in place. If I ever need to take it off, some pliers should do the trick.