3-size spool holder

A holder for different size spools: 32 mm, 38 mm and 48 mm. Print 2 of those, use 2 (or even 4 bearings) and place it on a 8 mm shaft.

Supposed to use with 608 bearings.

Inspired by http://www.thingiverse.com/thing:80580 But this one uses less material and matches better with Felix printers