"Main Spar Assemblies Mating - I set the spars on 4 saw horses and used the three 3/32 pins to align the spars. I made two 3/16th pins and inserted them in the two wing attach block holes. I then clamped the spars together inplace. After verifying that there were no clearence problems and that the spars where aligned I updrilled the 5 holes to 1/4th inch. The three 3/32 holes were done 1/8 5/32 3/16 7/32 and 1/4th. I started with the center hole. After reaching 1/4th I inserted a AN4-10 bolt to help hold the location. The two attach block holes I first redrilled with 3/16th. The next larger 6"" drill bit I have is 1/4th so I went directly to the final size. I did use candle wax to lubricate the drill bit."

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