MMU 2 Filament Spool Holder

thingiverse

My solution to the Prusa MMU2 spool holders. I found the stock Prusa roller trays to be overly complicated, prone to jamming, and space hogs. Over my years of 3D printing, I never had good luck with roller trays - they tend to jam, rolls fall off, and are sensitive to the filament rolls rim design. I wanted a way to hang spools and reduce the space needed. I also needed a better way to control ejection coils. I built my stand out of 1/2 PVC pipe. PTFE tubes feed through the cross brace, held in place with rubber bands looped over each. This allows for easy separation of the printer and stand. After testing, I added a second bar to prevent spools from back feeding and tangling by keeping ejection coils between two spreaders. Short pieces of PTFE are hot glued near rolls to reduce friction - hindsight suggests drilling smaller holes could have provided friction fit. By twisting this bar, I can control the back-feeding of filament. I recommend using a PVC tubing cutter (see last picture). This gives precise, square cuts. The frame is pressed together and the hardest part was cutting PVC tee fittings to act as supports for the spool rod. Spool weight keeps support rod in place. Works awesome. Fits right behind printer and after weeks of printing hasn't jammed or tangled. I added a PTFE tube separator below the MMU2 to keep tubes going straight into unit. Prusa MMU2 PTFE Tubes Separator by fucosk https://www.thingiverse.com/thing:3166394