Low Friction Spool Holder for Wanhao Duplicator i3 and Maker Select

I made this spool holder upgrade so that it can easily fit all the spools that I own and provide extremely low resistance on the extruder. To make this you will need 4"-4.5" of 5/16" threaded rod, three nuts, one washer (recommended), and two standard 608ZZ shielded 8x22x7 miniature ball bearings. (these are the same ones that all fidget spinners use!)

Other Maker Select / i3 style printer mods I've made:
http://www.thingiverse.com/thing:1923257
http://www.thingiverse.com/thing:1921236
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