5 Dollar Filament Spool

I really like 5 Dollar Filaments from http://www.protoparadigm.com/5DollarFilament/, especially for project that I do not need a large amount of a special color. Just do not like the flimsy spools they come on. Design this replacement that can be used again. This was the second attempt, first one was not worth publishing. Used 123d Design included files. Currently has 28mm center the spool holder I use (http://www.thingiverse.com/thing:1428581), which why I included the files so that others can change the center.

Use 3 3mm screws to hold it together. I used 20mm long ones on mine.