I started work on riveting the rudder spar and ribs together as part of final assembly of the rudder. The first step directed riveting on the spar doubler plates where the nutplates would secure the hinges to the spar. The plans made no rivet callout for the rivet length required to attach the nutplates to the spar and reinforcement plates, even though they had callouts for attaching the reinforcement plates to te spar. I used the rivet length guage to determine that AN470AD4-6 rivets would work dest in this situation.
The plans also contained no callout for attaching the counterbalance rib to the spar, in this case I simply opted to use AN470AD4-4 rivets in place. this seemed the most logical based on previous uses in this and other structures.
I was able to attach the R-405PD Rudder control horn along with the associated R-917 shim, nutplate, R-606 reinforcement plate, and the R-904 Bottom rib with the correct size rivets. To attach the R-710 horn brace, I elected to use AN470AD4-4 rivets on the upper attachment points, However te plans advised that swapping to LP4-3 pulled rivets was possible on the lower four rivets. I didn't feel that the use of driven rivets here was ideal based on the lack of working space. As such, I opted to install LP4-3 rivets.
