A space saving spool holder/filament guide system for use with the Prusa MMU2. Low drag on the filament. Drag does not increase as much as spool empties. Less tangling of filament behind printer/keeps looped filament up and clear of bed/cables.
The filament guide arm is counter weighted to act as a retracting mechanism to lift the filament as it is unloaded from the hotend.
You will need some parts:
608 bearings - 3 per holder (you can use the Prusa provided ones for their holders)
3mm x10 screw- 1 per holder
5mm x 10 screw- 1 per holder
5/16"-18 x 5" carriage bolt- 1 per holder
5/16-18 nut- 2 per holder
1/4" x 1-1/4" (5mm) fender washers- 7 per holder
4" length of 1/2" EMT conduit- 2 per holder
PTFE tube- 1 per holder (use existing tubes provided with Prusa kit)
I used 3 perimeters with 4 top/bottom layers & 20% gyroid infill for the base. 2 perimeters & 15% infill for the guide_arms & other parts.
you will need 2 pipe caps & 2 tube caps per holder - 1 each of all the other parts
Assemble the guide_arm & PTFE_guide with ACC glue.