The control surface was fun to work with. I have learned to really read and follow the directions. Everything is not spelled out. You have to read and interpret the plans. Once the top skin is riveted using bucking bar and flush set, you have fun squeezing your hand and bucking bar inside to rivet the BOTTOM skin to the spar. Be careful so you limit the indents to the outer skin from the fush set. The air pressure was set at 40lbs and that worked real well. You also have to watch to use the right length rivets. Notice in the outer corners longer flush rivets are called for because you are joining 3 pieces of aluminum.. The plans called for AN426AD3-3 for the rear surface double flush riveting, but AN426-3-3.5 worked perfectly. You back rivet the rear-most surface after you dimpled both sides and countersank both sides of the tail wedge that fits between the two surface skins. Remember those holes and countersinks are at 84 degrees, not 90 degrees because of the angle going on back there. It all worked out fine. The most difficult part for me was curling the skins in front of the main spar and pop riveting them. It did not occur to me that the pop rivets used a #30 drill bit. I spent some time figuring that out. Also, if the round stick you use to curl the end skins is too large in diameter, you don't get a nice curl, you get a nice curve. I was using a 1 inch wooden dowel. I should have used something like a 1/2 inch or something smaller that the 1 inch diameter rod. I got it to work, but it was not easy. Live and learn. The thing that started settling in was how to rivet. It becomes easy fairly quickly. I only had to drill out two rivets.
