I am trying to replace the exterior door trim on my 66 chevy pickup. The trim clips have nuts that have to be attached from inside the door. I am having a devil of a time getting the door panel screws out. Neither cobalt or titanium bits seem to drill in them. The ones I have drilled in far enough to get an ezout into have just snapped the heads of so now I'm left with the broken bolt. What kind of bit will drill these stainless screws?
I drilled one of mine out with a new normal drill bit. Next time try this. Heat stubborn screw, nut, bolt with a propane torch and melt as much candle wax into the threads. (or, try to draw the wax in by "capilary attraction" of heating one side and melting wax in the other) I have had amazing results using this method. Good luck with the drill-out and any future stuck screws.