The final tasks on the rudder assembly are the riveting of the trailing edge (earlier bonded into place using tank sealant), riveting of the hard-to-reach narrow sections of the top and bottom ribs, the setting of the rivets inside the lower brace, and the curving of the leading edge.
The rivets in the narrow aft portion of the ribs have very little clearance around them and they cannot be set using the squeezer or a normal bucking bar. Here is a close-up view of the aft-most rivets on the top rib:
To set these rivets, I used the back-riveting plate and two pieces of steel bar shaped for this purpose:
The top bar was used as a lever to transmit the impact from the rivet gun to the shop head of the rivet. The lower bar served as a fulcrum for the lever. This worked well, but it was difficult keeping everything aligned during riveting.
The final task was to shape the leading edge sections into curves that fit in the aft section of the vertical stabilizer. I did this one section at a time:
The curves were formed by taping a wooden dowel to the tabs of aluminum sheet and carefully bending them around the curve of the dowel. Once shaped, the halves were clecoed together, drilled to 1/8″ (#30) for the blind rivets, deburred, and finally riveted permanently together.
The result is the completed rudder assembly: