I spent some time today getting the top rib riveted along with the skins to the main spar. The counterbalance rib was riveted on next. Then it was time to move onto the trailing edge of the rudder and riveting a “double flush” rivet. Essentially a normal flush rivet where the shop head is set in a dimple and set flush to the skin on both sides.
I ended up using my pneumatic squeezer to partially set each of the rivets along the trailing edge. Starting in the center and working towards the outside edges, I partially set every 10th rivet, then every 5th rivet. This kept on until all rivets were partially set. I then used a flush die set in a C-frame rivet set holder in my rivet gun to finish each shop head flush to the skin following the same pattern that was used to partially set them. All the while making sure that there was no bowing, hooking, or pillowing of the edge going on. An overview of the technique below:
I’m not 100% happy with how it turned out, but that’s just the perfectionist in me. The results were a relatively straight trailing edge.
Next up is rolling the leading edges. The idea here is to tape the metal to a rod and roll it upwards creating a nice even bend in the metal.
I recently read on Van’s Air Force a tool that Eric, a fellow RV-10 builder, had created to make this job easy. I decided to give it a try, so in preparation to do that, I spent some time fabricating this tool from some closet rod, two 3/8″ drive sockets, and JB Weld that I bought from Home Depot.
I had purchased 1.25″ diameter closet rod, as that is the size suggested in the RV-10 plans, and 7/8″ sockets, which fit perfectly inside. I cut the rod to match the length of each leading edge section to roll. I also drilled some holes in the closet rod end and also used the grinding wheel to scruff up the sockets for better adhesion of the sockets to the rod.
Once this dries overnight, the idea is to use two 3/8″ drive socket wrenches in each end to easily roll the metal taped to the rod.