MP Select Mini Universal Bearing for stock spool holder

thingiverse

The stock spool holder on my Mini is a hard-edged beast that jerks the filament violently as it rolls. This creates a cascade of problems, including excess vibration and resistance on the extruder gear, not to mention the ear-piercing noise it produces. But fear not, because this quick 30-minute print has a simple solution. To fix it, simply print two bearings upright with support touching the bed in your filament of choice. Drop them onto the stock spool holder and slide them under each end of your spool's center hub. And voila! Your filament feeding machine is now rolling smoothly.