Drilled forward cockpit side details to 1/8" size. Broke 4 1/8" drill bits drilling through. The up-sizing of the holes is hard on a drill bit anyway - no working up the cutting surface to the full size, more of just impacting the chip removal flutes with the cutting force, but the polished surface seems to play into this. I have not experienced this problem before. Also, adding Boelube to the drill bit makes it immediately grab and snap. I was able to remove the broken bits ok and finish the holes with an old more dull drill bit.
