Adjustable Spool Roller

**THIS DESIGN IS OBSOLETE! Please see the newest universal design here:**
http://www.thingiverse.com/thing:1185076

This is filament spool roller that can accomodate 1kg spools from both MakerBot and DF Robot. The roller uses a couple of patio door ball bearings that you can get from Home Depot for $13. The bearings are notched, which cradles the rim of the spool while allowing it to easily turn. The base of the roller has two slots that allow you to adjust the width of the roller from 65