I was regrinding a razor tonight for a fellow, and had taken it down to the 800 grit cork belt for final belt polishing before buffing. All of a sudden, for no reason, a chunk just falls out of the blade. The blade hadn't been banged on anything, and up until then, the regrind was proceeding pretty rountinely. Still don't really know what happened, other than there must've just been a flaw in the blade. Luckily for him, I have a similar-sized W&B here I'd already reground and just didn't do anything with. Guess I got a use for it now. Stuff like this'll make you scratch your head, but I reckon it's the cost of doing business.