Spool Holder for Printrbot Simple Metal

I have an updated version here...
http://www.thingiverse.com/thing:510696

I wanted a simple spool holder that fit these 4 requirements:
Required no extra parts after printing
Required no support material during the print.
Mounted securely above the Printrbot
Rotates vertically to feed the filament (working with gravity), minimizing strain on the extruder gears.
Well, I couldn't find one like that, so I made my own!