This is a remix of a remix to make a large ball bearing, 100mm in diameter. This is not a simple scale down that would have also reduced tolerances and made the bearing too tight to spin well. I've scaled the housing and the balls differently to ensure the 0.3mm tolerances are maintained, so the bearing runs smoothly.

It does need supports under each ball, but I found the tree type supports to break off cleanly and easily. The bearing runs well as printed but smooths out as you run it more. A few drops of light weight oil also helps it run smoothly.

This size prints fast and is a fun fidget piece to keep on your desk.

If you're looking for something larger, try my Giant 200mm ball bearing:

https://makerworld.com/en/models/187884#profileId-206999

Or the original Large 145mm ball bearing:

https://www.thingiverse.com/thing:520238