Printrbot Simple XL - Spool Expander

The newer XL tower kits fixed this issue, but if you have an older tower kit with 4 casters, it only really fits the included spool. Instead of rewinding filament or only ordering from brands with the exact spool size, just print 2 of these spool expanders to allow any size spool to sit on the tower.
Printing recommendation - This is a tall object to print, your z calibration might be a little off since small amounts will multiple with 180 layers. This takes about 1 hr to print. Use a piece of