On race cars the floor trays are often carbon composite flat panels and
held to the main carbon tub by countersink Allen screws. Grounding or
general butchery sometimes makes the female hex unusable, or they are
rounded off. Drilling is often the only way to remove them, by taking their
heads off and removing the rest with grips once the panel is out of the
way. HOWEVER, I get through umpteen bits like this, good ones I might add.
What am i doing wrong, a pistol drill is the only option. I start with
maybe a 1/8 bit then go to something like a 5/16 or 3/8 bit. I now have a
retirement home for knackered drill bits..... Is there some trick to this?