After a little practice on some scrap aluminum, I back riveted the stiffeners onto the right rudder skin tonight. It was getting late by the time I finished, so I didn’t try to tackle the left skin. Riveting at midnight isn’t ideal with young kids sleeping in the house. It was a little slow at first as I measured each rivet with digital calipers to calibrate my technique. In the end I was moving quickly and getting a consistent head on each rivet. A couple of rivets ended up driven slightly more than I was aiming for, but are still within tolerance.
This was my setup, with a practice piece on the back riveting plate.
I started with this stiffener, and was happy with the results. I later increased the PSI from 20 to around 22, and the difference was noticeable; fewer hits needed to form the shop head. I’m using a 3x gun, which has a lot of power.
Here are all the stiffeners fastened to the skin:
I realized yesterday that I don’t have a #40 countersink that will work on the trailing edge wedge. Because the countersink is flush with the side of the wedge, but the hole isn’t (it’s perpendicular to the chord of the wedge), I need a countersink with a short and/or tapered pilot. I could probably grind one down, but I only have one. So I went ahead and ordered the special part from Cleveland tools. $20, and will arrive on Monday. That means I can’t finish the rudder until next week, but what’s the rush? I can always start on the Horizontal Stabilizer.