Flap skeletons

With flap brace parts fabricated, bent and predrilled as necessary I started fitting them to the flap skeletons. The aft-most hole on the rear brace lines up with a prepunched hole on the inboard rib, so positioning the brace is relatively easy. With a cleco in that hole I match-drilled and clecoed the forward end of the brace, then drilled the rest of the holes through the rib. After making sure that the angle was snugly in place and still clamped securely, I match-drilled the angle to the spar…at least the holes I could reach.
The upper flap skin must be removed to finish match-drilling the angle to both the spar and the inboard rib’s forward tab – in fact, the spar is sandwiched between the angle and the rib tab. I know, clear as mud. If you’re to the point of building your RV-7 or -8 flaps, you’ll understand. Some holes can be drilled from the front, but the three holes closest to the angle – the ones that go through the angle, spar and rib – have to be drilled from behind with a 12″ flexible #30 bit.
The end result looks like this…
One last detail – that reference hole at the rear end of the brace gets enlarged to accept the rod end that attaches the flap actuator arm. Once that hole is drilled, two others are drilled for the nutplate that holds the rod end. A nutplate threaded on an AN3 bolt made a good drill jig. The forward nutplate hole is countersunk to accept an AN426 rivet, and according to Vans’ plans the rear hole should be too…but the rib really isn’t thick enough to countersink. I have some AN470-3 universal head rivets, so I decided not to countersink the hole.