Dave’s RV-7A Building Log

Got home early after the yearly parent/teacher conference. I did another session with the labels and had one successful out of 3. Not bad. After thinking about it overnight, I decided that the fuser (a.k.a. laminating machine) is getting too hot. That’s why the first session worked well yesterday and the next two didn’t. The lettering is sticking too well to the mylar. I’m going to keep chipping away at the labels in short sessions every day. Hopefully after a week they’ll be done.

I worked on the wing tips some more. I sanded a couple spots down a bit more for a better fit and drilled out to #30. I cleaned up the notch of the cut out for the ailerons. I also fitted and drilled the ribs that reinforce and close off the trailing edge of the tips. The last task was to drill out the holes in the skins to #28, deburr, and dimple. Just a couple more things to do on the wings and I can move them down to the hangar.

And one of those last things is installing the pitot tube. Unfortunately, the Gretz pitot tube does not fit into the Gretz pitot mount. Not a big deal. The instructions suggest grinding it down with a Scotchbrite wheel. The pitot tube is such an odd shape that it’s difficult to get all surface in contact with the wheel. I had to remove the safety cover. Once I finally got them fitting together, I discovered the screw holes don’t line up. Come on. These two parts came from the same guy and they don’t even come close to fitting together. Time to haul out the Dremel.

I also took another look at the fuel flow sensor. I think using a 45 or 90 degree fitting on the outlet will solve the fit problems. I’d prefer the 45, so I’ll try that first. Almost time for another Spruce order.

Most of the day was taken up with leaf raking, gutter cleaning, etc. The rains finally stopped so it was time to work outside and enjoy the relatively nice weather. I also managed to get down to Boeing Field for a couple of touch and gos. As expected for a VFR day, it was very busy in the pattern.

After posting on the VAF forum and reading the instructions, it was obvious I needed to trim away some of the wing tips. I trimmed away just enough so the wing skins would fit into the recess in the tips. I then needed Julie’s help to mark 1/4″ over from the ailerons.

I turned to the flap sensor while waiting for her to return. It took quite a bit of messing around. I had to remake both parts, but got it all figured out eventually. The angle needed to be primed, so I took care of that. Picture soon when I get it all assembled.

I got some further advice on the labels from Frank at Pulsar. He said another builder with a powder coated panel also had some trouble. He suggested putting a light dusting of the glue spray on the panel as well as spraying the label. And I talked to Bill Repucci on the phone who suggested using a blunt object like the end of a spoon to really rub the label onto the panel. Sounds like a good plan. I also gave the panel a good washing with Dawn in the bathtub, just to make sure there were no residual oils on it.

But as a wise builder once said, man cannot live on labels alone. My order from Spruce finally arrived (last time I use USPS), so I worked on aileron rigging instead. I installed the bellcrank in the left wing and hooked up the pushrod to the aileron. Radomir sent me some advice in email for aligning the aileron. I was trying to align all of the tooling holes, which isn’t correct. The idea is to align the tooling holes in the wing rib with the trailing edge of the aileron. That makes a lot more sense. I’ll still double check the aileron position once I can get at my plywood stash and make a template.

I tweaked the pushrod lengths with the special alignment tool in place on the bellcrank. Now I can easily set the ailerons back to neutral position for fitting the wing tips. It takes an amazingly long time to get all the bolts and washers in place and everything torqued down. The bolt for the pushrod attachment to the aileron is especially difficult to get at. Hopefully I won’t have to remove the ailerons for transporting the wings.

I had another half hour left before my appointed quitting time of 9pm, so I installed the lower spark plugs. I’ve been putting it off, because I was afraid preservative oil would pour out of the cylinders. There’s only a light spray of oil in there, so none poured out. I discovered I almost completely boofed up the EGT placement on the right side. The probes are really close to the spark plugs. I have to remove one probe to install/remove the spark plug, but that’s not a big deal.

Installed the ailerons again in preparation for fitting the wing tips. The last time I installed them, I jammed in the washers exactly as specified in the plans. That didn’t really work very well. This time I installed washers to fit the space. Much better. The plans are way off on the washer call outs.

I set up the aileron neutral position by lining up the tooling holes, but I’m not very happy with that method. I can’t get all the wing and aileron holes to line up at the same time. I’m not sure which holes I’m supposed to use. Time for more research.

I hadn’t cut the bushings yet for the push rod attachment, so I did that on the band saw followed by drill press. It used to be fun making the bushings, but after a dozen or so bushings around the plane I’m tired of it. I picked up some plastic bushings at Lowes to go over the aluminum bushings. These serve as aileron stops. I measured the upward deflection with a digital level, and it’s almost exactly 32 degrees. Perfect. Thanks to the builder(s) that thought of that idea.

Installed the AOA ports on the left wing. The only tricky part was figuring out how to dimple for the #6 screws. I ended up using the 2X rivet gun turned down real low with the #30 dimples and the set holders from the long reach dimpler. Worked really well. Leo was supervising.

I also did the service bulletin for the left tank. Unfortunately, I had a brain fart and tried to turn one of the stainless socket head screws tighter rather than looser. I ended up stripping the socket. I made a quick run down to the hardware store for a #1 screw extractor and picked up two dozen new #8 socket-head stainless screws. Figured I’d better just replace them all and not press my luck. I also picked up a couple 1/16″ drill bits, as a broke my last one on the other tank. Once home, I drilled a 5/64″ hole into the stripped screw per instructions, and the screw extractor worked perfectly. Drilled the fuel pick-up nut, torqued, safety wired, and cleaned up the residual Proseal. Almost time to break out the Proseal cartridge. The “$20″ service bulletin so far is more like $50.

I had a little more time in the day, so I made a new top ignition wire to cylinder 2. Another fairly long day on the project, but productive.

I didn’t get much done, as I wasn’t feeling well. I started the process of finishing the details in the left wing. It will take a little longer than the right wing because of the pitot tube and AOA ports. I tried to install the bellcrank, but didn’t have enough AN3-6A screws. I at least got the bushing trimmed down a bit.

Julie helped me flip the wing onto some saw horses. I installed the remaining tank screws and taped the Duckworks light template in place.

I started messing around some more with the flap sensor, when Julie volunteered to help finish the riveting on the left bottom wing skin. I jumped at that opportunity. It was just more of the same rivet pounding, with the minor complication of the pitot mount. It feels really good to finally have the riveting on both wings done. Thanks Jules. She caught a picture of me jammed in this tight space inspecting some of our riveting.

For some reason, I only get motivated to work on the plane after noon. Despite that, we got a ton accomplished. Julie helped me a bunch with the left wing bottom skin riveting. We got the entire inboard skin riveted. It definitely seemed to go quicker than the first wing. I followed up by squeezing the flap hinge rivets and inboard-most rib.

I also decided it’s high time to get the panel painted. I removed everything from the panel and pulled it out. Didn’t take as long as I thought it would. Looks kind of sad missing the panel.

With the panel off, I drilled holes for the parking brake above the left switch bank and holes to mount the alternate air bracket. There was also one hole in the panel that was pre-drilled for a support rib that I’m not using. I filled that in along with a minor spot that the water jet cutter seemed to have slipped while cutting. I did a ton of other tiny stuff on the panel like cut the cabin heat control cable to size and take an inventory of instrument mounting screws (for ordering hex cap screws from McMaster).

Very productive day.

There’s more to these landing lights than I expected. It mainly took a while because I spread it over so many sessions. Well, I finally finished the one for the right wing. The instructions make it sound like the lens will fit through the hole with the bracket in place, but I didn’t find that to be the case. No big deal, though. Just wait until the end to secure the bracket. I used the tape handle trick to hold the lens in place, drilled, deburred, dimpled, etc. In the end the plexiglass fits pretty good. There’s a couple of gappies at the top between the screws, but it still looks great overall.

There hasn’t been much progress this week. Last night I went to a runway safety meeting at Renton Airport. I was expecting more specific local information, but it was all generic stuff like yellow lines are taxiways and white lines are runways. Yawn.

Tonight I got a bit further on the landing lights, installing nut plates for the bracket and then putting it in place. I trimmed the plexiglass lens to size as well. It seems to be a slightly different material than the canopy plexi. Using the fiberglass cutting wheel for the big cuts, it kind of melted instead of making a snow storm. I used the stationary belt sander to get right to the lines, which also made kind of a melted slurry.

I just about have the landing light wrapped up, and that’s about all I did this week. Hopefully this weekend will be productive as next week isn’t looking much better with Halloween and Adele’s birthday coming up.