With all those shims in place, it was time to drill the flap hinge and lower skins to the skeleton. With the spars and shims drilled, match-drilling the lower skins was easy. Drilling the flap hinge took a little more work, since it’s one, long floppy piece of AN piano hinge. There’s also very little room for error when drilling it with the proper edge distance as specified by the plans.

The first step was marking a centerline on one leaf of the hinge. I fabbed up a homemade edge marker block similar to the one sold by Avery Tools and marked the leaves of both flap hinges. I then clamped the hinge in place on each flap spar, making sure to align the centerline and spar holes. One minor trick…I used small pieces of thin plywood between the clamps and hinge leaf to avoid squeezing and deforming any hinge eyes. A few minutes with the Sioux and a #41 drill bit, and the hinges were match-drilled to the spar. I then match-drilled the entire structure to #40.
Things were going great, I was on a roll…so I decided to finish up by match-drilling the upper flap skins to the lower skins, spars and flaps I had done over the last two days. I grabbed those flap skins, clecoed them in place…and then found a problem. Remember that picture from October 6?
If you noticed before that the trailing edge bend didn’t look right, you’re very observant. Other builders have had the same problem with flap skins delivered in late 2005 and received replacement skins at no charge. I called Vans and reported the problem, we’ll see what they propose.