Damn. my dad was cutting off a mounting block (round stock with dovetails) and the cut-off tool wasn't set right, probably too high. I could hear it rubbing on the part. He launched the cut-off insert into never-never land, plus damaged the lower "jaw".
Looks like a "T" blade is in my future, I can't afford to let him learn that way. Course, he's hard of hearing, so he probably didn't hear the death scream...