Dave’s RV-7A Building Log

The ailerons are done!!! I woke up before the family and had an itch to finish the aileron I started yesterday. I finished it off in an hour or so, still before anybody was up. I threw it onto the wing with just a couple of bolts to check it out. Too cool.

After breakfast I polished off the other aileron and temporarily mounted it as well.

There wasn’t anything too difficult about riveting the ailerons. I used the control surface break to hold the trailing edge nice and straight. Seemed to work great. Both ailerons look perfectly straight to me. Tightening the bolts on the smaller brackets was tough. I ended up putting a wrench on it sideways sort of jammed in there. That worked ok. I torqued all of the nuts to the correct value and sealed them with paint. One minor thing I did mess up, was that the third bolt on the larger bracket (the one that goes in the nut plate) apparently needed an -10L washer instead of a -10 like all of the other bolts. I thought about it for quite a while to decide if it would really make a difference, and then just decided to fix it.

Clecoed one aileron together in preparation for finishing off the riveting. Set half of the remaining rivets on one aileron.

Another big day. Julie helped me rivet the top and bottom skins of the ailerons to the top of the spar. From this point, I think I can do the rest solo. It looks like the remaining riveting is blind or squeezable.

I screwed the aileron spar to a 2×4 on each end and clamped that to the workbench and rolling tool cart. It worked out great. We each had great access for riveting and bucking. I’m not sure why some people have trouble with this step. I found it to be pretty easy.

I started off by priming the inside of the counterweights. It would have been much easier to do this before drilling all of the holes. I taped over the holes and poured in some primer. One of the holes wasn’t well sealed, and I ended up with paint everywhere. Oh well.

I then started to put together the aileron skeletons. Van’s has definitely changed the nose rib to counterweight connection. The instructions say to do this blind rivet first, which is pretty easy to do. Just bend the tab a little bit, pull the rivet, and then bend the rib back in position. Very easy.

I also riveted the reinforcement plates to the spar and the spar to the nose ribs.

The last thing I did on the ailerons today was to cleco the skins to the top of the spar in preparation for riveting. I’m going to wait until Julie can help with it, though.

The hot weather has finally broken. I was going to fly this morning, but we have very low ceilings. I don’t even mind, because today will be 20 degrees cooler than yesterday. Whew!

Cleaned, prepped, and primed the aileron parts. I also sprayed some rattle can self-etching primer on the inside of the nose rib where it will contact the counter weight galvanized pipe.

This is the entry that broke the 500 total hour mark on the project. I’m hoping to get this thing done in less than 2000 hours, so hopefully I’m at least 1/4 of the way there!!

Countersunk the holes on the reinforcement plates for the ailerons. Deburred the ends of the counterweights and countersunk the attach holes with a regular drill bit. The instructions go to great length to say the countersink can be 100 degrees instead of 120 degrees, but they don’t say what difference it makes. The Orndorff video suggests not to use countersink cutters as they will get chewed up by the steel. Instead, a regular old drill bit is good enough. It doesn’t make a pretty countersink, but it works fine.

I then did the trick of putting the counterweight plus nose skin on a couple of 2×4’s and whacked a dimple die into the skin. Works pretty good.
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The CS4-4 rivets aren’t going to set perfectly flush anyway, because the skin bends right there. I also dimpled all of the other holes on the spars and skins. For being so small, the ailerons have a lot of holes. I think I’m ready for primer.

The counterweights are each just a tiny bit longer than the nose skin. It’s only about 1/32″ on each side. I’m not sure if that is important or not.

I noticed on somebody’s web site that they had polished the outside of the counterweight. I don’t think that’s a good idea. A galvanized pipe is fairly rustproof, because of the galvanization. It’s a thin layer of I think zinc. If you sand that off, it’s not going to be very resistant to corrosion.

It has been blazin’ hot here lately, mid to upper 90’s. It just doesn’t normally get that hot here in Seattle. The shop was toasty:

Deburring the aileron parts took a long time, especially the nose ribs. Watched Lance clinch his record six win while filing and sanding away. All of the parts are now deburred. On to countersinking, dimpling, priming, and finally assembly.

Spent more time deburring the aileron structure and skins. For being so small, the ailerons sure have a lot of edges and holes to deburr.

Julie offered to schedule a riveting “date.” If she isn’t at work too late, maybe we’ll get something done on the wing skins tomorrow. I think it helped when a neighbor stopped by Sunday and was asking about all the rivets taped into the wing skin. “What are these for?” “Oh, I’m just waiting for some help with riveting.” I was almost afraid he was going to volunteer. I wouldn’t be excited about training a new riveter on the top wing skins.

Last night we were at the Mariners game. The M’s are not doing well this year. They were down 4-1 in the 8th and we were tired, so we headed home. Wouldn’t you know they pulled out 3 runs in the 8th and 9th and then a grand slam in the 11th. Oh well.

Finished drilling the first aileron. Clecoed together and drilled the second aileron to final size. Drilling the galvanized pipe takes quite a while and makes a mess of iron shavings. Drilling the hole that holds the little tab to the galvanized pipe is tricky. The instructions say to go through one of the holes on the spar with a long drill bit. It works!

I just noticed something interesting. On Dan’s aileron drilling page at the bottom, you’ll notice that the tabs on the aileron nose ribs point inward. Apparently, Van’s changed this since the tabs now face outward. I guess this was done to make drilling and pulling those blind rivets easier.

I also started deburring all of the parts.

Working on the ailerons is pretty fun. It reminds me of working on the empennage. After a few dozen hours, you have a complete part versus the hundreds of hours that the wings take.

Clecoed one aileron together and after carefully checking the rivet call-outs, drilled most of the holes to final size.