Today I drilled both F-695 forward fuselage gussets to the main longerons and top firewall cross member (photo 1), which required a long #30 bit to clear the firewall and adjacent clecos.
Next I laid out and drilled the F-636 seatbelt anchors to the main longerons just forward of the F-708 bulkhead (photo 3). The layout required drilling the aft bolt hole 17/32" forward of the forward edge of the bulkhead flange as measured perpendicular to the bulkhead web, however it was much easier to use my dial calipers to measure from the aft face of the bulkhead, so I just added 5/8". To drill the holes on the left side, I tried using my transfer punches then pilot drilling with a #40 bit, but somehow the holes came out a little off center, so I had to drill out with an 11/64 being careful to drill light enough so as to not allow the bit to follow the offset hole. On the left side I went straight to the 11/64 bit with good results. I finished the holes on both sides with a #12 reamer.
I finished up the day by deburring all new holes in the structure and all holes and edges in the gussets and anchors. Deburring the holes on the underside of the forward gusset structure was a bear due to access, and I had the best luck using my pilotless countersink bit in my right angle drill and just feathering the trigger to get a few turns (photo 3).
I'm going to wait until I have a few more small parts before prepping and priming.
F-695R drilled to structure.
Right forward gusset rivet holes after deburring.
Shoulder harness anchors drilled to main longerons just forward of the F-708 bulkhead.
