Dave’s RV-7A Building Log

I was getting a bit burned out on the camlocs. I decided to finish off the canopy and put it back in the guest room out of harms way. I riveted on the exterior handle and bolted on the latch fingers. Done deal. There’s some minor boogers in the primer, but it’s certainly good enough for flying.

Since I had the back rivet set out to do the canopy handle, I decided to work on the one rivet in the rear fuselage that needed back riveting. The rivet also holds a clip for the static line. Since the line transitions from under the longeron to above and it has to avoid the harness bracket, I made the clip stick out and up a ways. I also secured the static line while I was back there. Should be my last trip back there until inspection time.

From there I went back to the camloc strips. I trimmed the bottom ones a little more to avoid the honeycomb on the bottom cowl. I then riveted them to the firewall/bottom skin and riveted the camlocs to the strips. I was going to use solid rivets on the camlocs, but there is not much room. Since they provided cherry max blind rivets in the kit, I used those.

I installed the cabin frame, hopefully for the last time. I was going to rivet the support to the frame, but noticed it got pretty scratched up while fitting the canopy. I took it outside and shot it with another coat of paint.

Might as well install the F-704 covers. They’ve been waiting forever. I’m still not sure how to protect the wire to the lights that will be in the covers, but I’ll probably just use some poly tubing. I also installed the latch catch with spring. The catch is a bit stiff, but should loosen up over time.

I thought I was done for the day, but Julie went to work and Adele went to swim team practice. Might as well do some more. I had never done the final trim on the bottom cowl exhaust area. I trimmed that even with the rest of the cowl and sanded it smooth. I also started working on prepping the hinges to be riveted on. The instructions suggest drilling 1/4″ holes in the hinges for the epoxy to grab, so I did that every few inches. I also roughed up the hinges and cowl with some coarse sandpaper. The last item for the day was some retainer clips for the side hinge pins just like Dan did them.

Whew! Long, productive day.

Not much happened over the last few days with Julie’s birthday and other stuff going on.

I found some time today to work more on the camlock backing strips. I scalloped the other strips and countersunk all of the holes. Time consuming.

I also managed to do some painting in between rain storms. I put another coat on the cabin frame, painted the canopy latches, and put the final primer coat on the canopy fairing. Everything turned out great.

The weather did not hold out as was predicted. The rain prevented me from doing the last of the canopy painting. I didn’t have much time for the project anyway. Julie’s birthday is tomorrow, and I’ve been busy working on some things for her.

For plan B, I worked on the camloc strips some more. I’ve been debating about whether to scallop the camloc strips as I’ve seen other builders do. The weight savings is minimal. The only real benefit is that the camlocs can contour to the shape of the cowl better. Since the bottom strips need to be cut back anyway because of the honeycomb in the cowl, I did some experimenting. It was easy to do, so I’ll probably do the top strip as well.

I was reading some old posts on camlocs and ran across a good piece of advice. Since I’m keeping the hinges along the bottom part of the sides, I need to make sure I can get the hinge pin out. I’ll need to eliminate one camloc on each side. Had I known that in the first place, I wouldn’t have made the separate backing strips for the sides. Oh well. At least the spacing and positioning of the camlocs is still good.

May was a very productive month. Looking back over the past two years, I always seem to get a lot done in May. I guess the combination of decent weather and the Memorial Day weekend help boost the hours.

I did just a bit more sanding on the canopy to bring the upper edge of the fairing even with the single layer of electrical tape. I also sanded out a couple of spots that were rough. One more shot of primer and it’s good enough to fly.

I also sanded and prepped the cabin frame for one more shot of paint. It was just a little to bumpy after the last coat.

Today was the first unofficial function of the Eastside EAA 1440 chapter. A few of us flew down to Thun field. It had to be an unofficial function, since our chapter is not officially formed yet. Mike and Michael brought their Luscombes, which are really a pretty plane. And Ron was there with his Fly Baby, which looks like pure fun. Some day I’ll arrive in style in an RV rather than a 172.

I had a little time for the project. I re-drilled the left canopy lug and drilled both lugs out to #12 for AN3 bolts. Julie helped me remove the canopy from the plane, since that was the last thing I needed to do while it was installed. It was extemely difficult to get the struts off. There must be a trick to that. I have a few more little things to do on the canopy and then it will get stored until final assembly.

After dinner, Julie helped me finish the riveting on the back top skin. I could have reached some of the rivets from the outside, but it’s easier to just crawl inside. This skin has been in the process of being riveted for a long time (Christmas) mainly because it just wasn’t a big priority. It’s nice to have it done.

I crawled back inside again to attach the shoulder harness cable brackets. One more trip back there for the static tubing and that should be it for the rear fuselage.

I worked some more on the camloc backing strips. It’s really not obvious how to install these. I initially cut them too short. Luckily I had some extra material. I clamped the strips right where I wanted them and started drilling down from the middle.

I also drilled out the hinges I previously installed along the bottom and cut and drilled strips for that area. I’m going to keep the hinges on the sides.

Then it was time to enlarge the holes in the backing strips with a Unibit. This step makes a huge mess.

I countersunk the bottom strips, clecoed them in place and enlarged the holes in the cowl. I installed the collars and camlocs into the cowl and then test fit it. Looks good.

Long day, but very productive.

I sanded the filler on the fairing and shot another coat of primer on it. It turned out much better this time. It’s good enough for now. I’ll do more prep work on it later, maybe even wait until I get it painted. It’s certainly flyable right now.

I decided to fit the canopy latch fingers onto the canopy. I wheeled the plane out into the driveway and Julie helped me get the canopy on. It’s tough to get the pins lined up. Initially I tried to keep the forward top skin on, but without being able to cleco it down it was obvious there would be binding. I just took it off.

I attached the gas struts and watched the canopy lift on it own for the first time. Very cool.

After some fiddling around, it became apparent that the holes in the canopy deck were not big enough. I used the cutter in the Dremel to extend them forward. Even then if the canopy doesn’t come straight down, it will bind up on one side or the other. I might need some spacers under the fingers.

I placed 1/8″ spacers under the canopy rails and removed the cabin frame. From there I positioned the fingers, marked them, and drilled them on the drill press. The left one got way off center. I thought it was going to be fine, until I realized these are attached with bolts, not rivets. Time to order a new one.

One thing I noticed is that with the gas struts pushing the canopy upward, there’s a sizeable gap under the front of the canopy. Hopefully once the forward top skin is on, this will be reduced.

(Edit 5/15/2006: After sleeping on it, I figured out the issue. Without the forward top skin in place, the whole subpanel assembly has shifted forward. That explains why the latch fingers aren’t fitting through the holes in the canopy deck and why there is such a big gap under just the forward part of the canopy.)

I was hoping to take the canopy right back off again and store it until final assembly, but now I need to order a new latch finger and wait for it to arrive so I can mark and drill it correctly.

After dinner, I did some prepping and filling on the cabin frame. I decided to use some filler since the gap between the two halves is so wavy.

I wasn’t sure I was going to do anything on the plane today, but Adele was busy playing with her friend and Julie was happy working in the yard. Sounds like a great Mother’s Day to me.

I painted the F-704 covers and upper baggage bulkhead. They turned out great.

I then turned to sanding and filling the canopy fairing. Pretty boring, so I didn’t snap any pictures.

I did have a little fun today. I rented a 172 and did some touch and goes at Boeing Field. Even though the wind was right down the runway, with all the hills and building around BFI there was a lot of mechanical turbulence in the air. Very bumpy and swirly. I did 4 T&Gs and was proud of all but one. Not bad. Still knocking the rust off.

The microlight filler is much easier to sand. I sanded down the canopy fairing starting with 80, then 100, then 150, and then 200. The shape looks great. I found that feeling the contour was a better indicator than looking at it. I kept sanding it little by little. I would try painting some primer on it, but the wind really kicked up today. I’ll wait on that step.

I was planning on installing the latch fingers. Thus, I installed all the canopy latch hardware. I’m not sure why I didn’t install these before. I guess I painted them and then never put them in. Installing the mounting points for the gas struts was really tricky. A little EZ-turn helped out. That stuff is super sticky. I used that to stick the washers and nuts to the tip of my finger while I turned the screws. I didn’t install all the cotter pins yet. They’ll be tricky, and I’m not sure if I’ll need to remove them again anyway.

I think I finally have the cabin heat muff figured out. I’m going to have a custom muff made. I’ll feed the fresh air into the bottom of the muff.

The outlet will then point aft where the SCAT is positioned in this picture.

The tubing will then fit between the intake tubes and sump. It’s tight in there, but I can secure the SCAT to the oil return lines. I think it will work out quite well.

I also messed with the breather tube. The angle oil adapter interferes with the standard route. I think using a straight section of the radiator hose, I found a route that will work. It might requre a little tweaking of the bends in the tube.

I hadn’t planned on spending so much time on the plane today, but I got a lot done. It’s nice to see the interior coming together.

I spent a heck of a long time sanding down the filler. I wish that I had just used the microlight filler. It’s much easier to sand. I also wish that I had been more careful about squeezing the excess from the top edge. Sanding along that line without going right through the electrical tape was very time consuming. I eventually got it sanded down to a decent shape.

I ended up removing the electrical tape, as I was worried that I had sanded through it in a few spots. Turns out the tape was fine. I replaced it with another double layer of tape.

I mixed up a batch of microlight filler and smoothed that very carefully over the fairing area. The nice part about the microlight is it tends to self-level. I learned how quickly epoxy can flash. I had quite a bit extra in the cup and it turned into a ball of smoking epoxy. I’m glad I noticed it before it melted through the cup.

Leo decided I was spending too much time on the plane and not enough with him.

While the epoxy set up, I went back to installing the control cable eyeballs. I enlarged all the holes to 1-1/8″ and made a new hole for the alternate air cable. I used the template for the eyeballs to drill the 6 little holes. On almost every one, I had to file a little bit to make it fit correctly. The eyeball for the mixture was especially difficult to work on. I had to crawl inside the cockpit for that one. It’s great to have the eyeballs installed. As soon as I get the control cables figured out (and the panel back from Ross), I can install the quadrant and cables. The far right hole in the second picture is for the alternate air.