Dave’s RV-7A Building Log

EAA 1440 meeting last night. Terry Burch talked about building challenges and first flight issues. Very interesting stuff. I’m thinking about using him for my first flight. He has a ton of RV experience.

I received engine sensors, wiring harnesses, and AOA kit from AFS. Woohoo! Everything looks top notch.

I started by installing the cylinder head temp sensors. Those went in very easily. Next was the oil temp sensor, then oil and fuel pressure. I also started running some wires from the EFIS harness around.

I spent some time trying to figure out where to install the fuel flow sensor. It’s a red aluminum block made by Electronics International. I went on their web site and found some more info on mounting. It can be mounted with any of the following sides (or combination thereof) pointing upward: wires, cap with 5 screws, outlet. There weren’t any restrictions mentioned about straight tubing before or after. If that’s the case, I might install it on the vertical run of tubing up the firewall on the cabin side. Second choice would be right after the mechanical pump.

The other challenge is the manifold pressure sensor. I need to run the manifold pressure from the 1/8″ NPT fitting on the cylinder to the 1/4″ barbed fitting on the sensor AND to the two 1/8″ barbed fittings on the P-mags. I’m thinking about using an AN840 fitting on the cylinder with a mini clamp and then running Tygon tubing to the sensor and P-mags via some T fittings. I’m just not sure about attaching plastic tubing to an engine fitting. Tygon is supposed to be abrasion and chemical resistant, and handle temps up to 200-250F. I’ll figure out a way to restrict the flow through the AN840 fitting just in case the tubing ever does burst.

I did some of the solo work on the right bottom skin, like squeezing the rivets along the inboard edge and flap hinge. I also drilled out (why does Van pre-punch some nut plate holes to full size and not others??), deburred, dimpled, and riveted the nut plates in place for the access panels.

I spent most of the weekend finishing up the move of my web sites to a new server, which will hopefully be faster and more stable.

Julie and I spent a few hours continuing the riveting on the bottom skins. We’re about 3/4 of the way through the right wing. We’ve mostly been following the Van’s instructions of riveting in an L pattern, although I still haven’t figured out which way the L is supposed to be facing. I’ll probably get it perfected as soon as both wings are done.

After consulting the usual sources, I decided to put the wing back into the cradle for riveting the bottom skins. I used some boards between the cradle and the wall to keep it from moving while Julie leaned into the rivet gun. The rivets along the rear spar in one of the wing walk bays were pretty tough, but nothing was impossible. We got half of the wing walk area done.

The BNC connectors arrived from Mouser and they are indeed the exact same ones as from SteinAir. I hooked up some coax for the VOR, glide slope, and marker beacon antennas.

I also tried out some knobs I ordered from Mouser for the dimmers. I like it better than the blue knobs I picked up at Radio Shack a few weeks ago.

Yesterday was my lucky day. Renton airport called and informed me that a hangar became available. I was actually #7 on the list, but the hangar is in a tight spot, so the first 6 people passed. The apron is only about 32′ wide out front. A little tight, but doable for an RV. I went and looked at it today, and wrote a check for the first month’s rent. Renton is much closer to my house than Auburn, and will make it much easier to get the plane finished down at the hangar.

Now I just need to sell the hangar at Auburn (S50). Anybody need a nice condo hangar?

My order from Spruce arrived with the VOR/GS splitter. I mounted that to the subpanel and strung coax from the right side of the fuselage to there for the VOR/GS and marker beacon.

Waiting on the order from Mouser before I can hook everything up. I had a little trouble running the coax through F-704. The snap bushings are reduced in size a little bit because of the poor placement Vans has on these bushings. They’re right up against the doublers, which squish the bushings. I ended up having extra room in the bushings in the middle of F-704, so I moved the COM2 antenna over there. Problem solved.

Didn’t get much done. I installed most of the bolts and screws for the right fuel tank.

Didn’t get very much useful work done. I spent some time looking over what I needed to do before riveting on the bottom skin. I thought I might want to install the autopilot servo, or Duckworks landing lights. I looked over the drawings and instructions and both can easily be installed with the bottom skins in place. Must be time for some riveting. Julie helped me get the right wing out of the cradle and onto a temporary work surface. I read through the instructions for riveting the bottom skins and got mentally prepared.

Pop riveted the seals in place. The RTV didn’t hold so well. The seal material puckered between the rivets and lifted right off the RTV. Maybe I should have riveted them with the RTV not set up?? It won’t be a big deal. It seems like the seal will still push tightly against the baffle.

Worked on trimming the baffle seals to fit. I cut a few notches to allow the seal material to conform to the cowl and trimmed around the inlets a bit. The cowl seems to be sitting down pretty good. The process reminds me of trimming the baffles. It’s a lot of taking the cowl on and off and trimming.