Brief Description: snapped a drill bit in center spar
I was working on the last bolt hole through the 4130 steel strap following the dihedral setting, and in the process I snapped a drill bit down inside the hole. This was a big problem which I worked on for the rest of the day without success. The drill bit that snapped was a 7/64, which is what I have been using to start these bolt holes, step drilling them up to 15/64 and then using a reamer to finish them to exactly a quarter inch. I was using a brand new 7/64 bit, and it had made it through the top 4130 strap and through the aluminum layers, but when it hit the bottom 4130 strap it snapped, deep down in the assembly. I started drilling with larger and larger bits, hoping to drill through the broken piece, but it just was not working. gave up and went to work on nose ribs.
