I put off back-riveting the trailing edge as long as I could, and finally ran out of excuses. I decided to follow several other builders' paths and alternate shop head/manufactured head to try to limit any distortion (Van's limits deviation from a line stretched from top to bottom of the rudder along the trailing edge to 0.10").
First I taped in half of the rivets, then followed Van's instructions, partially setting every 10th rivet, then every 6th.
The 3x rivet gun with a back-rivet set at about 40 PSI made this easy, and I was glad to have practiced this in the EAA Sportair Workshop.
The rivet set starts vertical relative to the rivet, and after a few taps swings perpendicular to the surface of the skin.
After partially setting all rivets on one side, I flipped the rudder over, finish-set the rivets with the mushroom head rivet set on a swivel at 50 PSI. Once this was done, I repeated the above steps on the opposite side.
I did manage to slightly mar the skin in 2 spots, but all rivets were set clean with good shop heads, and our deviation measured at 0.0470", so we're within tolerance. Whew!
The last step (for forming metal, anyway) involves rolling the leading edge. Some people buy new dowels for this...
It took some finesse & re-rolling, but all 3 sections came together.
I squeezed some pop rivets, and voila - another finished part!!
I still need to install rod-end bearings (which allow the rudder to connect to the vertical stabilizer), and install the fiberglass top and bottom, but I'm calling this one complete.
Empennage: 2 hrs
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