A filament spool holder for the Printrbot Simple 1405 XL that replaces the factory designed bearing filament roller, as we found this design did not work well based on the fact that it did not allow for a variety of filament spools to be used as well as we found that it caused a force on the extruder (creating instability in the Z position of the tip). Our design uses the existing bearing bolts and bolt holes. Unfortunately the designed was too big to print on the Printrbot Simple 1405 XL (because of the 100mm Y axis max) so we printed it on our Replicator 2 but it should print on a Metal Printrbot Simple. SketchUp file included for your convenience.No support needed, however the bottom right tail of the Pi character will print a little imprecise and should really have a small support for proper printing.