Simple Spool Holder Roller

I use a variety of spool sizes with my printer, ranging from wide spools to the slim Replicator Gen 5 spools. Recently I printed out the simple spool holder by 3DMakeMe (link: http://www.thingiverse.com/thing:281848), and, rather than making multiple holders for my various spools, I designed this roller.

Update 11/24/2014: Printed out the rollers, turned out to be slightly too long. Also, the bearings took too much force to install. The model has been revised accordingly.