About this 3D model

This is a derivative of http://www.thingiverse.com/thing:77301. I really liked the design of the spool holder but it was designed for a 10mm tube and I wanted to be able to use standard skate bearings on my filament rolls. I redesigned the holder to accept a 8mm or 5/16th solid rod. I have printed it and it works perfectly! Mentioned in more detail here: http://coherent-reprap.blogspot.com/2013/05/my-first-customized-part-new-filament.html