How do they do it ???

For an ordinary bearing, all the balls are moved together on one side, and they fit in that way - then the balls are spread out by the cage, which is riveted or welded from two bits of metal, one on each side.

For angular contact bearings, it sometimes varies - they sometimes use liquid nitrogen and heat, and sometimes for full complement bearings there is a slot in, usually, the inner race through which the balls are fed.

But even for these unusual bearings, again, mostly the balls are fitted in place while touching each other, and then kept seperated by the cage.

-- Peter Fairbrother

Thanks. That was seen on the TV show, but to be honest, some bearings don't look to have enough room between the balls to do that. I guess the easy way to prove to workmates is to remove a cage and try to take it apart. Thanks Bob