Charles I used the Ultracote to make the hinges for the flaps. I cut them 1" wide and 1-1/2" long and placed them right next to each other to give me a sealed hinge line. People refer to them as "Monokote" hinges but I do not use Monokote brand, I use Ultracote brand.
On the elevator I did the same thing only I used Dacron hinges, doped them down and then painted over them.
Mike