Worked on left outboard wing: Riveted rear spar backer plate to spar. Also drilled & reamed inside four holes of plate, spar and rib attach bracket for AN3 bolts. Had to file off about 1/32" from the back edge of the trailing rib backer plate in order for the rib to clear the rear spar and fit flush against its attach angle. I polished the end of the rear spar backer plate since it will be exposed when the wing is folded and cannot be painted.
Drilled and reamed to AN3 size the main spar mounting holes for the first rib attachment. I had already riveted the attach bracket to the front half of the rib but not the rear half which was good. I first drilled the spar holes out to #40 holes and then used pieces of a metal coat hanger as alignment pins. With the front rib and attach bracket in place along with the read attach bracket, I used 2 welders clamps to clamp the attach brackets to the spar and then I drilled and reamed the two inside holes of the attach brackets from the rear. I then inserted 2 AN3 bolts and tightened them. Then I removed the welder clamps, drilled and reamed 2 more holes, inserted 2 more AN3 bolts and then drilled the final 2 holes, 6 holes total. I also used a Dremel tool to grind out the spar web blocking part of the short aileron rod pass through.
Used a similar process on the second rib from the inside folding rib location except instead of AN3 bolts, it uses 8-32 screws and nuts. The rest of the ribs are riveted and will be up drilled to the spar to #30 holes similar to the first two ribs.
Should be able to match drill and bolt/rivet all the ribs tomorrow provided the weather doesn't get too hot and unbearable like it did today.
Read spar backer and attach bracker attached.
2nd rib attach bracket being match drilled.to spar
