Tri Fidget Spinner with Balls

created in Tinkercad. It has a nice weight to it and enough mass for a decent spin.

a common 608 skate bearing is used in the center. The outer bearings are 6 1/2" stainless ball bearings. Mine measure 12.67mm and the hole is designed to be tight at 12.7mm. I press fit carefully with the bearings heated up. I used my toaster oven, be very careful they are hot and will burn you. The center bearing snapped into place with a little bit of force. I have center caps designed that are decently thi