Flap 1
Once you get all the ribs clecoed up and trial fit, you need to check the rear spar/rib intersection. As instructed in the book, I had to make small shims on most all of my ribs. I cut little squares out of .020, .025, and .032 and arranged them till they fit right. I had to use two shims on some of them, as the gap was very large.
I don't have a picture, but you will also need to make small shims for the bottom of the end ribs where the top skin overlaps.
Next step is fitting the hinge. The plans call out the edge distance, so keep that in mind. I marked a centerline on the hinge at the appropriate distance, so I could see through the holes whether I was lined up or not. The trick with fitting the hinge is to eliminate friction. You can't just clamp it on and drill, or it will be very stiff. I found it best to "rough" fit it, then loosen all the clamps and slowly retighten one at a time. This seems to eliminate some of the preload. As you can see, I used small c-clamps to keep everything together.
Next comes time to c-sink the spar. You keep the hinge clecoed on, as it acts like a guide for the pilot. I blocked and clamped the assembly to the bench, as it made it much easier to work with.
The attach brackets are then fabricated out of angle stock. One you will have to rip a portion of the angle in half.
The other bracket is pre-cut, but it must be bent at a 6.3 degree angle (yeah right). Given that the aluminum was 1/8" thick, this can't exactly be done by hand. This is extremely difficult to do, and I tried doing it two different ways:
clamping it in a vise at the bend line and whacking it with an 8 lb hammer
slitting a steel pipe down the middle and sliding it over the bracket to pry (with it clamped in a vise)
Neither method worked well, but #2 was a little more effective. It does not have to be exact, just as long as everything fits up correctly (and it does).
Once the brackets are made you need to c-sink for the attach nutplate. The attachment is a little confusing, as you c-sink the bracket on one side and the rib on the other.
The instructions don't say to rivet the inboard bracket on until it is in the skin. It looked much easier to do first, and it worked out well.
