Riveting Leading Edge Skin

Between more snow then we've seen in ages and a few days with the flu, I'm a little behind what I had hoped. I found the easiest way to rivet the Leading Edge skin to the Spar aft edge was with my trusty rivet squeezer. The inspection mirror made it easy to see how the shop end formed. Near the compression ribs the skin had to be clamped to hold it tight while riveting because the compression member sits on top of the spar. I had modified the squeezer in the past for repairing Cub ribs and that worked great for getting the tools down close to the spar. The hardest part was remembering that the Spar Flange is not square to the Web so the squeezer handle had to be tipped down to keep it square to the flange. If not held right the rivet would bend and have to be drilled out and start over.

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I found it easier to work this edge with the Leading Edge down. I fitted the drag wires in and adjusted them to hold everything straight. They have to be out to rivet the compression members on the forward side of the Spar.

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Because of the angle of the Spar Flange the rivet on the forward side needed a special bucking bar. I got some 1" x 1/2" steel bar stock at Tractor Supply and made this bar to fit around the ribs over the lower spar flange and provide a surface square to the rivets. The handle allowed me to hold it well even though the mass was a little light. It worked well for both 3/32" and 1/8" rivets on both sides of the ribs. .

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I ground the tip at a 14 degree angle and the 45 degree relief at the top so it would clear the lip of the flange when riveting in the area of the doubler. The tip is radiused and polished.

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The cut out was sawed to a 1-1/2" radius so I could smooth it on the roller end of my belt sander. I screwed the handle on but would have welded it if that were available in my attic shop.

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Everything went well. The 5/32" rivets for the drag wire brackets take a fairly heavy bucking bar about 4 lbs. to form the heads well

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The top surface of the skin is now on and I just have to figure out how to pull it tight to locate the lower rivet holes. I have the feeling I should have bent the Skin more to the finished shape. The drag wires are permanently installed and the wing trammeled per the factory service letter.