I got inspiration for this from another spool holder, but decided that it needed a hinge for easy loading and unloading of spools. I also sized it to utilize cheap electrical conduit as the solid rod ($3 for 10 ft. at a hardware store). It should fit any printer that uses the same 12mm smooth rods that the printrbot has.
1.This spool holder sits on the smooth rods, so it reduces your max build height. If you need the extra couple mm, just remove it.
- When X carriage is raised up high, don't attempt to home the X axis. The spool holder will hit the extruder motor, and it won't reach the endstop switch. Just make sure not to hit "Home All" when the X carriage is very high.
Simply print out the pieces, glue a piece of conduit into the hinge piece, and attach it all with a 4mm nut and bolt.
The hole for the 12mm smooth rod is slightly oversized. To make it fit snugly, you can wrap a layer of blue painters tape around the rod to slightly increase its diameter. It will fit snugly if you do this.