Would wonder about shatter resistance. Not experienced with ceramic bearings, but in most things, there is a trade between hardness and flexibility. Make something too hard, and it may break or shatter under high pressure, such as the leading edge of a drill bit focussing all the force into a very tiny surface area.
The ceramic bearings is probably a great idea, but love Squelchtone's idea of putting bearings there in the first place.
Perhaps you could drill a hole in the end of the screw about the size of the bearing, so the screw still has the strengty of all the threads. The bearing would reinforce the inside of the screw, keeping the threads from collapsing under tension during a snapping attack, yet still provide drilling protection.
See what happens when a 'simple' question is brought up here? We pool our ideas and come up with some good suggestions.
Absolutely love this site for the continuing ingenious ideas that pop up.
Gordon
Just when you finally think you have learned it all, that is when you learn that you don't know anything yet.
)
