04-19-2011: 3hrs
Continue deburring, boring!04-20-2011: 10hrs
Continue deburring and smoothing, boring!!04-21-2011: 3.5hrs
Continue deburring and smoothing, boring!!! Finally deburred and primed left side HS parts, using DupliColor self-eching primer, I got the primer in a local auto parts store, cost about $6/can. It is cheaper than getting from NAPA store ($9/can). I used the empennage packing card board as my priming bed. For surface prep, I use actone to wipe clean the smoothed parts until I don't see black stuff on the paper towel. For skin, I only prime the areas in contact with other parts (ribs, spars, etc.)
This most inboard hole on the HS702 (right side) has a small edge margin e/D=5/3=1.67. Fatigue strength reduction factor is about 0.94, while static strength reduction factor is about 0.90. The static strength of the joint (426AD3 and 0.032" 2024-T3 sheet) with 2D edge margin is about 178 lbs, and is limited by the rivet shear strength. The bearing strength of the sheet with D/e=1.7 is about 198 lbs, still higher than the rivet shear strength. This small edge margin is acceptable
