Flaps 11 (2.5 hrs)


After priming the flaps in my last shop session, it was time to start final assembly. First thing first, I went to borrow my buddy Mike’s heater. Its better than my propane setup. I’ve never seen it state “LO” as the temperature. I guess it doesn’t read below 30… it was 20 degrees F outside… and in the hangar!(null)

Nothing warms my soul like a little beer!(null)

The first thing I needed to do was to make a cradle for the flaps. Van’s instructions calls for it, and its a good idea, but you can probably get by without one. I used some spare board I had laying around. I screwed the two pieces together. I used an end rib to trace where to cut, and then cut with a circular saw. I used my belt sander to make sure the bottoms were absolutely identical so they would mount to the bench and maintain a true alignment. (null)

I attached the little brackets I made for the ailerons as feet and then clamped the feet to the workbench. (null)

The first step was to rivet the rear spar and ribs. I started with the right flap, which unlike the left, required shims. (null)

Both flaps with the rear spar riveted to the ribs. (null)

Next, it was time to install the nut plates for the flap attachment point. Don’t forget to do this before you close up the flaps!(null)

The nut plate is a little odd, in that it has one rivet through the 706 and the other just through the rib. The directions call for the 706 to be countersunk for a 426 rivet, but there is no mention of the other rivet. The rib is too thin of a material to countersink, and dimpling would likely leave the nut plate slightly uneven. The course of action chosen by several builders is to use an Oops rivet, which needs significantly less countersink.(null)

Here is my Oops rivet set from Avery. For this I used the NAS 1097 3-3.5. (null)

In this picture I have already countersunk the hole for the Oops rivet (shown on the right). I have placed the Oops rivet in the left un-countersunk hole to show how little it protrudes. (null)

This picture is a standard 426 rivet for comparison. (null)

Final products. (null)

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