"W07 Wing Box - Today I first drilled out the rivets on the Root Rib angle on the rear spar. I did this so that I will be able to remove the angle when I install the root rib. Kerry at Sonex said to wait to install the root rib untill after the aft skins are fitted. Next I positioned the upper aft skin and drilled the #40 pilot holes for the row going into the rear spar. I made sure the edge of the skin and the edge of the rear spar were aligned. After that I made sure the frame was square. I located station 19"" on the main spar. Then using a square I made sure that it lined up with station 19"" on the rear spar. That station is where the bolt hole is located. Today I also started drilling the #40 pilot holes into the ribs. I lined up the ribs and made sure that there were not any edge issues."
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