Rollerspooler

Rollerspooler is the latest in TUSH-Varientalology, using the base Idea from the original The Ultimate Spool Holder (by filamentry) then adding the Clamp from the original Prusa Spool Holder (because, why reinvent a perfectly working wheel?) to mount it to a Prusa i3 MK3S+ Frame.

This is probably more industrial art than an honest attempt at creating something primarily useful.

There are many popular takes on this very combination of ideas, but if you like something new and purposefully different, then this the one for you.

Still, if you don't like the idea/insanity of something that looks like it shouldn't work as good as it does, you can just print it with default settings and have a working filament roller.

The dark areas of the model on the Image shows how much more could be removed without sacrificing any of its stiffness. Even more could be removed if the Validation/Analysis/Study wouldn't require a Safety Margin of five times the projected weight of 2 kg.

So, this should easily hold the probable normal strain of 1 kg. 

Instructions

• Print two sets of left/right each
  • 0.3 mm / Draft Settings
  • No Top/Bottom Layers
  • 3 Perimeters (makes screw holes more stable)
  • Variable Layer Height if you like
  • 20% Gyroid Infill 
  • Add a Range Modifier for 5 mm up and re-enable Top-Layer to make the Top Surfaces look neater
• Prepare (per set)
  • 2 — 608 Bearings
      or any bearing with an inner diameter of 8 mm and depth of 7 mm
  • 4 — M4x20
      Longer Screws can be used
  • 4 — M4 Nuts
      Lock nuts can be used but are not necessary

How to mount

1. Place 608 Bearing on Spacer of right Side
   • Bearings should have a tight fit but should seat without force
   • If the Bearing would require force to go on, check for burs or if it sits canted
   • Place printed Part flat on Table and press bearing on, not the other way around
2. Place left Side on right Side
3. Insert 4 M4x20 Screws through right Side
4. Add M4 Nuts to left Side
5. Tighten without inhibiting rotation of Bearings
   • Screws are only there to keep alignment between the two halves, no need to crank them down

FAQ

• Isn't there a large amount of side flex without the walls?
  • No. Especially not after having it sit on the Frame and screwed together, and also never to a point where it could have realistic impact on doing its job
• I don't have any Hardware on Hand, what should I do?
  • Use PrusaSlicer to make dowels from cylinders with a diameter of 4.5 mm and a length of 22 mm. They should naturally fit snugly enough to not fall out.
  • Alternatively, you can add these dowels directly to one side of each set before printing. Take your time to align them properly.
• The Screw holes are just hanging in there! That can't be safe!
  • The Screws are just there to align the set and keep the layers within the bearings from shearing off.
• If the Filament gets caught on the spool, isn't the Spool dragged right off?
  • The filament is more likely to be sheared off inside the extruder before there is enough force on the spool to tip it off.