Auto-rewind spool holder (for MMU)

thingiverse

This is an auto-rewind spool holder that automatically rewinds the spool on filament changes, completely replacing the filament buffer. As filament is dragged into the printer, a weight is lifted, and when MMU unloads the filament, gravity does the job of rewinding the spool. Check out this video on YouTube to see the rewind process in action: https://www.youtube.com/watch?v=TmQAFTuMKQI, or watch this other video that shows the "clicking" sound when the arm is on top during printing: https://www.youtube.com/watch?v=6MSmuZER7Ww. All you need to do is print the parts and add the bearings left over from the original MMU spool holders. You'll also require some screws to assemble the base to the stands, but any length between M3x14 and M3x40 will suffice. That's it! The entire set of parts prints in about 8.5 hours without requiring any supports. It's a pretty straightforward process, isn't it? # Supported Spool Sizes * Maximum spool width: up to 80/100/120 mm (different parts available) * Spool inner hole diameter: between 42-65 mm * Maximum spool outer diameter: up to 250 mm