Printrite horizontal spool holder

NEW: There is now a smooth variation of the spool holder. I have been using it for a long time but i forgot to upload it :( The original version with steps does not work as well as the smooth one.

This is a spool holder for the printrite diy printer that mounts on the screws holding the vertical rods on top of the printer. It has a universal design so it should fit most spools. It uses two regular skateboard bearings to achieve a friction-free spinning.