I have been avoiding doing fidget spinners since I figured they would be old hat by now but over the past month I have been doing Intro to Tinkercad classes and it is all the kids want to talk about and print. Of course since I don't have the ball bearings , I tried to explain it to them that it is better to have the bearing first then measure around it but they happily 3D printed ones that they could just spin using their fingers. They kinda reminded me of brass knuckles.... Coincidentally, I saw a post on Facbook highlighting how to build custom spinners. This blog has everything you will need and I am very appreciative. It took me a few tries to get the exact measurements so that the bearing would fit in snugly but not too loose as it would fall right out. My measurements for the 22mm bearing was using 2 cylinders in Tinkercad, one cylinder measures 27mm all around, 7mm high with an inner "hole" cylinder of 22.5mm all around, 7mm high. I highly recommend using Tin...