Dave’s RV-7A Building Log

Dimpled all of the seat and baggage ribs and then deburred the F-704 and F-705 bulkheads.

The picture Dan posted was so inspirational that I went back out to the garage and deburred the baggage ribs.

Deburred the rest of the seat ribs. Also removed the plastic from the bottom center fuselage skin in preparation for deburring.

Enlarged the tooling holes in the seat ribs. It looks like some are for wiring and some are for the pitot tube. Rather than trying to figure which ones I might need and might not need at this point, I just drilled them all out as indicated in the plans.

Also started deburring the center fuselage parts.

Drilled the sides of the center section and then disassembled the center fuselage. In the process of taking things apart, I realized I hadn’t drilled the seat and baggage ribs to the bulkheads. I did that drilling once the skin was off.

I also figured out that the outboard seat ribs didn’t need to be drilled so early. The instructions have you drilling them later in the process. It certainly didn’t hurt to drill them early, though.

One more thing I forgot was to trim the inboard-most seat and baggage ribs for the wiring holes through the F-705 bulkhead. I put the ribs on temporarily and marked the areas to be trimmed.

Speaking of things I need to go back and do: I need to trim the seat belt anchors so the seat ribs will fit. I also need to enlarge the tooling holes in the seat ribs for wiring per the plans. Lots of pick up work to do.

With the center fuselage apart, I should now have enough clecos to put the aft section back together. I definitely need to get more clecos. I thought the wings used a lot of clecos, but the fuselage really gobbles them up.

I picked up some temporary bolts at Home Depot for holding the center section together. They didn’t have 7/16″ bolts at all, so I went with 1/4″ bolts in the small holes. I put the two halves of the center section together on the center fuselage assembly and drilled out the holes on the front edge. I also countersunk the 4 holes that are indicated in the instructions and plans.

After that, I spent a bunch of time just studying the instructions and plans. The order of assembly is not immediately obvious, but I think I’m figuring it out. I’m not ready for assembly yet, but I like to stay one or two steps ahead of the game.

Drilled the center bottom fuselage skin to the structure.

Trimmed the corner ribs following the way that Matthew Brandes did it. As others have pointed out, the plans are very vague on how to trim the ends of the corner ribs. Seeing how somebody else did it saved me a lot of time worrying about it. Thanks Matthew.

After trimming a bit off the end, the corner ribs matched the skin edge within 1/32″, which should be good enough. The instructions say to flute the rib. It doesn’t need much fluting, just enough to match the slight bend of the baggage ribs. I worried for a while how to figure out where the holes are on the rib flanges, so I could flute between them. Turns out there are no holes in the flanges on the corner ribs.

After getting the corner ribs fitted, I drilled the bottom skin to the ribs. I also fitted the forward attach strips and drilled them.

The next step is to mate the two halves of the center section again, but I don’t want to use the close tolerance bolts. A few builders have bought plain bolts at the hardware store. That’s what I’m planning on doing tomorrow. I’m setting the center fuselage aside for now.

Seems like I haven’t had any time to work on the project this week. I was out of town one day, and just too beat tired the next. And even today I spent time on other stuff like raking leaves, blowing air through the sprinkler system, changing the oil in the compressor, etc.

I managed to do a few things on the plane. I finished riveting the nut plates on the seat ribs, and then put the whole center fuselage assembly back together again, including the bottom skin. The fit is a bit tight in places, but good overall. I fabricated the weird attach strips for the baggage corner ribs. Those things seem like a total after-thought. It seems like they could have been fabricated so that the attach strips aren’t needed.

After staring at the plans a while, I noticed some other snap bushing holes I need to drill out. I’ll take care of that after I take the assembly apart again. I also don’t have the seat belt brackets attached quite yet. According to Dan’s site, they need to be removed later anyway for skin riveting access. However, I noticed that I need to trim still more off of the brackets in order to clear the seat rib flanges.

Started riveting nut plates to the seat ribs.

Etched and primed all of the seat and baggage ribs. This was probably the worst painting session yet. The paint gun has been giving me more and more trouble lately. I cleaned it out twice while painting, and it kept clogging up. Well, I finally took more of it apart and discovered a screen inside it that was really clogged up. I cleaned that out along with all the other parts, and the gun works like new now.

The other problem was the weather. It never outright rained, but it kept sprinkling every 20 minutes or so. I had to keep running everything inside, wait for the sprinkles to stop, and then take everything back out and continue. Luckily the paint I’m using is water based, so the few rain drops that did fall on the parts didn’t ruin the paint job. It’s good enough for primer.