Print in place Ball Bearing

This is a print in place ball bearing, REV 5 has .45mm of clearance for printers with less then perfect dimensional control, REV 6 has .2mm of clearance for printers with better dimensional control. Can be printed with bearings in place.

If printed with the correct supports ball bearing rolls completely smooth making 4-5 rotations before stopping. I'm using this as a bearing for my Inland 1kg spools in conjunction with the http://www.thingiverse.com/thing:1375089 printer upgrades I'm doing no