Van's RV-9A in Aurora

The Big Picture

The Big Picture
Flying! 8/28/2011

Thursday, January 31, 2008

Right HS assembly

Built a jig to hold the completed left HS. Felt bad just letting it flop around while working on the right side. Should have cut one, or even two, extra jig plates when I built up the factory set. Since these aren't super critical (the factory jigs aren't either, really!), I just traced the outline of the cutout onto 1/4" plywood. Didn't even bother to remove the cloth strips from the original. Cut it out with the band saw, attach a 2x4 for a base, duct tape for scratch protection, and voila - a well supported HS half.

With a way to hold the left HS, started the right HS assembly.
Clecoed the front spar to the right skin and nose ribs.

Installed the blind rivets to join the middle rib/spar/nose rib. Really people, the blind rivets are quite sufficient for this application. There's no need to go to extraordinary pain to drive 1/8" rivets at this spot. If there's enough stress on that joint to break the blind rivets, the rest of the plane is already in shards.

Riveted the inboard main rib/spar/nose rib attachment. Did not forget the shim. The -8 rivets are a bit too long, and they're difficult and awkward to drive. Used the double offset universal set for this.

Started riveting the front spar to the skin. Got a good start, driving rivets solo (I never know where that girl is anymore), and then saved the rest for later. I think the secret to driving 3/32 rivets is to use ~40 psi. Too little and it takes too long. To much more, and you greatly increase the chances of damaging the skin. At 40 psi the gun is controllable and forgiving. It does take more to set the 1/8" rib/spar rivets, and even the 4.5 skin/spar/rib rivets take a few extra hits to set properly.

BTW, I love the 3x Souix gun. Don't think twice. Just spend the extra dollars to get it. The trigger lets you adjust how hard and how many times the gun hits. Like the -8 rivets for the inboard nose rib/spar/shim/main rib joint. The rivet can be very difficult to push in. One or two gentle taps with the rivet gun and they're nice and flush, without any violence.