Dave’s RV-7A Building Log

Did some serious dimpling. Adele helped me dimple the rest of the inboard top left skin and wing walk doubler with the C-frame. Those are now ready to rivet. Since I need something to rivet them to, I dimpled all of the ribs and rear spar with the pneumatic squeezer. Adele got some pictures of me dimpling:

I also deburred the holes on the outside of the left top outboard skin.

One thing to watch for on the pneumatic squeezer when dimpling with the adjustable set: sometimes it loosens up a bit. I had to go back over some holes when I noticed that it was really loose.

We also let loose the rockets tonight. Very, very fun. Those things really cruise way up there–supposedly 1000 feet.

Had 10 daughter and dads over at the house tonight to make rockets. Fun stuff! We’ll be launching those babies soon.

I spent a little time dimpling around the edge of the top inboard left skin with the pneumatic squeezer. This skin seems to be taking forever, working on it a few minutes here and there, but at least it’s moving forward. If I wasn’t chipping away at it, it would still be completely unprepped.

Finished deburring the left inboard top skin. It’s ready to be dimpled now.

I also put in a little time smoothing the edges of the left inboard top skin and deburring some more of the holes.

ProSeal session #2. Can’t think of a better way to spend my birthday (not). I managed to rivet in two ribs, the cover for the tooling hole on the outboard rib, and spread some ProSeal on the connector for the capacitive plate. Julie helped me with the second rib, and things went much, much faster. I’m going to beg, plead, offer back rubs–whatever it takes to get help on the other ribs. It’s just so much faster and easier.

There was a nice breeze blowing through the garage today, so I mainly wore the respirator during clean up with the MEK. It was nice not wearing that thing the whole time.

I got plenty of ProSeal on everything and still had 1/2 tube left over. There was a couple of spots in the tube that didn’t seem mixed very well. I threw them out. I’ll do more mixing next time. The directions say 50 strokes with the mixing ram. I’m counting each direction as one, but maybe that’s not enough.

Overall, the session went great.

After a few days busy with family and work, I’m finally back on the project today. Most of the day was spent re-organizing the shop. I took down the paint booth, since the weather here in Seattle is getting good enough to paint outdoors. I changed the oil in the compressor, put up a shelf over the work bench, and finally hung up the drawings. I can see the work bench again!

I spent a little time finishing up the skin riveting on the left leading edge–again solo. It definitely takes 3 to 4 times as long to do the riveting solo. It takes longer to line up the rivet gun and bucking bar. You end up screwing up more rivets that have to be drilled out and re-done. But in the end, it still turns out great. On the last row of rivets I finally realized that it’s more important to watch the rivet gun than the bucking bar. I can hold the bucking bar in place by feel, but there’s no way to tell the rivet gun is going astray without watching it. I guess that knowledge will come in handy on the fuel tank. It sure is great to have a major piece (almost) finished. The wings take a ton of prep work before you see anything go together.

There is a little bump in the leadinge edge skins near the front of each rib. I tried to take a picture of it, but it doesn’t really show up well. I did some extra Scotch-brite work on the tips of the ribs, but didn’t want to grind right through the flange. It would be nice if the bumps weren’t there, but I’m not going to worry about it. I’ll try to eliminate them on the other wing.

I also deburred the rest of the top of the inboard left top skin. Man, there is a lot of skin left to debur.

Faxed in the order for the fuselage

Decided to attempt solo riveting. I started on the bottom of the left leading edge. There’s two reasons to start on the bottom. As Dan C pointed out, starting on the bottom allows you to lay the leading edge flat on the bench to rivet the top. Another good reason is so that hopefully you’re less likely to make mistakes by the time you get to the top where it will be seen.

Another trick I figured out was that I duct taped the leading edge into the cradle. That allowed me to lay the whole thing top down on the bench. Much easier to rivet that way, at least for me.

I got into a pretty good rythym filling in each rivet from back to front, working each rib a little at a time. Watch the rivet gun angle on the end ribs. The gun tends to want to tilt in toward the middle. I had to re-do two rivets, but the rest came out great. I’ll save the top for tomorrow.

Deburred some holes on the left inboard top skin.

Still waiting for riveting assistance from my better half.

Deburred the rest of the left main skeleton. It’s now ready for dimpling.

Moved on to the pitot tube mount. I’m using the Gretz mount. The instructions are good, but it still takes a bit of figuring out the best approach and laying out the holes. You get spoiled by the prepunched stuff.

I clamped the backer plate in place on the main spar and made sure it was square. I then back-drilled through the spar flange into the backer plate. I next laid out the rest of the holes on the backer plate.

I fashioned the reinforcement angle out of some .032 goofed up spar material that I had laying around from the HS. I laid out some holes on that and drilled it to the rib with everything clamped in place. I then clecoed on the bottom skin, back drilled through the backer plate into the skin (both the rivet holes and the screw holes), and then reattached the angle and back drilled through the skin and backer plate into that.

Whew! Lots of simple steps, but it took a while to get it all figured out.