Brief Description: Repair Per Van's Engineering Instructions
Summary: Drill and install 7/32 solid AL rivet.
Instructions: Comparing the diameter of the nearby LP4-3 in the photo, which is .239 in., the keyhole max diameter appears to be slightly under that. Recommend carefully cleaning up the hole by drilling to .219 or whatever size is recommended by the mfr of a universal head, 7/32 diameter solid AL rivet (see mfr info below). Use the match-drill method to align the drill bit and a piece of material that is at least 1/16 thick and pre-drilled with a 7/32 hole as a guide. If that yields a good hole then order the 7/32 diameter solid universal head rivet. A solid rivet is preferred over a blind rivet since the solid rivet will swell more and fill irregularities better. Also this size rivet will require a large rivet gun. See the rivet supplier contact info below.
Rivet Length: Recommended rivet length = material stack-up + 1.5 x D (where D = rivet diameter; for 7/32 D = .219 in) Total material stack-up = .040 doubler + .020 skin + .063 spar flange => .123 in. Therefore rivet length = .123 + 1.5 x .219 => .452 in. Rivets are supplied in 3/8 or ½ in lengths I believe but I fear 3/8 may be on the short side. Therefore to play it safe recommend ordering the ½ inch length and cutting them down slightly so as to minimize the chance of them bending over. Highly recommend performing a good number of trials beforehand to get a desirable bucked head dimension without having to use an overly long rivet to begin with and setting yourself up for failure.
