With one only skin on, the elevator rear spars are simple to rivet. The tungsten bucking bar (henceforth, "Mr. T", so dubbed by my RV-9A friend who lent me much help over four days).
The elevator rear spars, in the area absent the trim tab, are recessed behind a good 5.5 inches or so of skin. Always preferring squeezing to bucking, especially on control surfaces, I tried to get a super deep yoke, and after grinding away a notch to fit the spar, the yoke turned out not to fit my squeezer without grinding some of the bottom fork. Can't return that! So, I went with the special bucking bar suggested in the plans.
I used my steel plate to provide a rigid counterpoise against the lever arm, after shimming the elevator up.
A flashlight illuminates the contact point between the shop end and bucking bar since the bar will rotate around the fulcrum between it and the steel counterpoise during the violence of the bucking process. We managed this movement by hitting the rivet in 3 short, consecutive bursts, separated by enough time for me to yell "stop" if the bucking bar had slipped excessively. Right elevator shown below.
The left forward spar was easily riveted with the squeezer. Left elevator shown below. Skin is tight with the second-from-inboard lower sector having some oil-canning. I can reach in through the forward spar lightening holes to seal in a light stiffener. Shame, but not a big deal.
Right elevator isn't shown at the same state as above because I messed up two rivets holding the tip rib to the forward spar. When we drilled them out, it became a mess because access was, well, impossible. We managed to set the replacement rivets after upsizing one to an AD5 (from an AD4) but I didn't like how it looked. My tech counselor was okay with it, but in the end I decided I didn't want it in the plane, so I will be redoing the right front spar. I have a lot of scrap metal from this project!
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