Originally Posted by BWT
How about a weak magnet? I use my screwdriver that has a weak magnetic tip. Perfect for holding the balls where I want them, and then I just knock them off with my finger. Usually* they stick in the grease where I want them. Obviously, this means you have to put a layer of grease down first. This also allows me to flip the hub and do the other side without putting the cone in and the balls stay put! For this to work, you have to press the balls down into the grease a bit too.
Yeah, i agree with that. You can also coat the bearings before hand (especially tiny ones) with grease incase you drop one , it will help to keep it from bouncing &/or rolling away.