Determined that 4 holes in the R-710 Rudder holn brace were going to need to be blind riveted with CS4-4 rivets. Holes will need to be #30, so I match drilled those on each side. After reading that the CS-4-4 rivets are 120 degree instead of the usual 100 degree countersink, I realized that I need a new dimple die set, si ordered one as well as a 120 degree countersink made specially for CS4-4 rivets. Disasssembled the rudder and dimpled the subframe spar and ribs where I could with the 3/32 subframe die. Have to wait till I get the new set to finish it. Deburred all parts and preped most of the parts for priming and shot them with primer.
