Mounting the Ailerons   January 10th, 2010

With the wings in the cradle, I can now start mounting the ailerons on the wings. First I gathered all of the hardware required, as shown in the plans. There are two spacers that need to be fabricated from aluminum tubing. for the aileron-to-wing bolts. First I cut the aluminum tube slightly longer than needed, and chucked it into the drill press. I used a block of wood and some sandpaper (probably 100 grit – whatever I had around) and applied light pressure first to square the end of the tube, and then to get it to the final length. Using this method, I could take off less than 0.001″ at a time, so it makes for very precise spacer lengths!
Getting all those washers in the tight spaces of the aileron brackets was no fun. I probably dropped ten or fifteen washers on the floor before I decided to tape them together and put them in all at one time. I could now use needle-nose pliers to put the washers precisely where I needed them without having them slip and fall on the floor.
These are two views of the inboard aileron bracket — the bracket that holds the aileron to the wing and connects to the pushrod that controls aileron movement. As you can see, I am not tightening the nuts yet, as I will probably take the ailerons off a few times before this things flies..
While I am working on this part of the wing, I am going to install the bracket for the Dynon autopilot servo. You can buy the bracket now and wait until much later to buy the servo ($$) and autopilot/EFIS ($$$!) Basically, the servo mounts next to the aileron bellcrank, and it uses a small pushrod to move the bellcrank when the autopilot is engaged. In order to attach the pushrod to the bellcrank, a single hole is drilled in the bellcrank:
The bracket simply replaces the oiginal bottom bellcrank bracket, and it also includes another support arm that bolts from the upper bracket to the servo
I repeated the whole process on the left wing. Here are a couple of pictures of the aileron mounted on the wing and the bellcrank bracket (the autopilot servo is installed on one wing only).

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Riveting the Ailerons   April 26th, 2009

The ailerons are supposedly the ‘hardest riveting in the whole airplane’. Once I figured out how to do it, it wasn’t really that hard. I placed the aileron upside down in the fuel tank cradle, and propped the skin open with a roll of masking tape. I also placed a light near the opening so I could see what I was doing. The only tricky part was towards the middle of the aileron, where I couldn’t really watch the rivet from both sides (I would have needed gorilla arms). So, I placed the bucking bar in about the right spot, and watched the rivet gun. I just tried to hold the bucking bar in about the same spot as where I originally placed it. Most rivets turns out really good, and I only had to drill out one or two per aileron.
The picture below shows the bucking bar I used. I covered almost all of it in duct tape so I could place it right on the spar and it wouldn’t scratch anything as it bounced around.
Ok, so at this point the skins-to-spar rivet line on the top was fully riveted on.
The next step was to dimple the row of holes where the counterbalance pipe is riveted to the leading edge. The only way to do this is to take the dimple die and the arbor that comes with the riveting C-frame, and just hammer right into the hole (with the water countersink pipe in place, obviously).
The very last step is to blind-rivet the bottom spar to the skins. The only trick is to remembe to that these holes have to be drilled to #30, and not #40 like the ones on the top. Finally, here is a completed aileron:
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More Aileron Work   March 15th, 2009

I had some 2×8’s laying around. They were several years old and all warped. Rather than throw them away, I built a handy priming frame for all of the aileron parts:

And the last step before assembling the aileron was to countersink the counterbalance pipe. Rather than using a countersink bit, I just used a 1/4″ drill bit.

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Bending Aileron Skins   March 15th, 2009

The aileron skin needs to be bent to a fairly small angle before it can be assembled. Van’s recommends using a bending brake made out of 2×6 lumber. This is what I did for the elevators, but that was over a year ago. The wood became so warped I had to make another one. This time, instead of pine, I used MDF. I had some 2’x4′ MDF laying around, but I needed the brake to be just slightly longer than four feet. Rather than go out and buy a huge 4’x8′ piece, I made each section of two pieces, two layers deep. So, each flap is 1.5 inches thick, and 60 inches long. Because it is MDF, the brake is heavy enough that it won’t slide around like the 2×6’s I was using before.

The brake is so long it was much easier to have two people pushing on it to get a uniform bend. So, Fabiola got on one side and I got on the other, and we laid some weight into it…

Using this brake, and having two people doing the pushing, we got the bend to the right angle pretty fast, and the entire edge looked really good afterwards. Here are a couple of pictures of the ailerons fully assembled with clecoes, just before priming…

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Aileron Leading Edge   January 19th, 2009

Back to the Ailerons for a while… I have been working on the leading edges this time. The leading edge of the aileron goes somewhat into the wing, and has a counterbalance weight to make up for the weight of the aileron itself (picture it trailing the structure in the photo below)

The counterbalance is a steel water pipe! It fits right into the tip of the leading edge, and is held to the leading edge with a row of pull-rivets. It is also attached to the little side ribs with a single rivet. To drill this hole, the plans have a note about using a long drill to go through one of the holes in the spar right into this hole. I did not catch this, and just used my WWII-vintage 90 degree drill.. 🙂

Finally, here is me drilling the leading edge and water pipe
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Starting Aileron Construction   January 3rd, 2009

At this point we are ready to start riveting the main skins. Since this is a two-person operation, I’m getting started with the Ailerons as well. Fabiola and I will work on the wings as her schedule permits, and I’ll continue on with Aileron construction.

Here is a not-very-good picture of one of the aileron skins sitting on the bench, with about half the stiffeners drilled and clecoed.

While at it, I also drilled the reinforcement plates and aileron brackets to the aileron spar. The outer brackets are pre-driled, bu there are only two holes. I used these handy little vice-grips to hold them tight in place while drilling the holes to final size.

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