Minimalistic spool roller.
This will hold a spool while allowing it to roll freely to feed filament. It prints in one piece that will (barely) fit on a cupcake platform.
You will need 4 bearings with appropriate screws. I used 623s, but the design is, as always, parametric, so you can use whatever size you want. The STL is sized for MBI spools, which I measured as 74mm wide, but I've seen two or three other sizes, so measure your spool first! The one shown is from protoparadigm, and I had to print it 76mm wide.
Printer accessories and enhancements
3d printer upgrades