These are parts that I modified from http://www.thingiverse.com/thing:3066 to fit oak dowels that I already had. I also used the Spool bushing for 608 bearings http://www.thingiverse.com/thing:15868 created by

Miro87043 for the center.

Instructions

Print out one of each stl file and connect with 3/8" dowels or equivalent aluminum rods. Sides are 200 mm long and the bottom two can be as long as you want. I used a 1 foot long 5/16" threaded rod and nuts to go through the 608 bearings. It can hold up to three spools if spaced right.