Prusa i3 Mk3 Roller Spool Holder with Safety Bar

thingiverse

I've used both Olef's remix of DWONH's spool roller and my own version for my Einstart-S and Prusa i3 MK3, with amazing results. However, even with proper care, filament can sometimes get tangled or knotted, causing it to be pulled off the rollers. To prevent this from happening, I've designed a new type of roller stand that allows the bar to pass through the center of the spool without touching it. This way, if the spool gets stuck, the rollers will move freely and won't pull the filament onto the bed below. I'm pleased to say that after some trial and error, I've finally achieved perfect alignment on both Inland and Prusa brand filament spools using this new design.