This uses a 22mm bearing and 4, 1/2 inch steel ball bearings.
For the 1/2 inch bearing placement I channeled it out slightly so that the ball bearings have room to move so you can roll this spinner around on a surface or with your finger or thumb.
Included is an STL for the Caps that I used
Rafts:
No
Supports:
No
Resolution:
1.75
Infill:
50% or more
