This spinner can be balanced by turning three carriage bolts in and out of the three arms. If the spinner is held vertical, it can be balanced such that none of the bolts will gravitate toward the lowest position. The o-rings put more squeeze on the bolts (they could fly out at high speed), but they also make the spinner nicer to grip in your hand. I also chose to go with a standard hex nut and bolt for the thumb pieces just to keep with the mechanical look.

The second version is more robust and keeps a tighter grip on the screws.

Extra Materials: + (1x) 608 skateboard or fidget spinner bearing + (1x) 5/16-18 x ½ long Hex Bolt (for thumb piece) + (1x) 5/16-18 Hex Nut (for thumb piece) + (3x) 5/16-18 x 1 long Carriage Bolts + (3x) #204 O-rings (3/8 ID x 5/8 OD)