Dave’s RV-7A Building Log

Spent most of yesterday evening messing around with the computers. The fan in our Dell started making a high pitched noise a while back. Tried ordering a replacement fan. Same thing. I ended up replacing the fan with a quieter version. We’ll see if that fixes it.

On the plane, I marked and cut the hole in the right wing for the Duckworks landing light. I used a cut off wheel in the die grinder followed by a cutting bit in the Dremel for the corners. A bit nerve wracking cutting a hole in the wing, but it turned out really nice after some filing and smoothing. Drilled the holes for the attachment nut plates and that was it for the night. The drilling is a little tricky, but overall it’s been a pretty easy install even with the leading edge on the wing.

A must-do for today was to rent a 172. I can’t believe it’s been almost 3 months since my BFR, and I’ve done no flying. Boeing Field was a bit crazy when I got there with lots of business jets arriving for the Seahawks game. By the time I was in the air, I was the only one around. Eerie. I did 4 perfect touch and gos (not surprising considering the perfect weather) and called it good. I’ll need to do a lot more flying to get ready for the test phase.

With the wing riveting done, it was time to install the servo for the wing leveler autopilot. I assembled most of it on the bench, although doing the safety wire for the servo bolts would have been a really good idea, too.

The bellcrank had some fore/aft slop in it. I chucked the brass bushing in the drill press and shortened it up about 1/32″. That caused a minor problem when I went to install the assembly in the wing. The bolt holes didn’t line up. I added a -416 washer between the bushing and the bellcrank bracket and the problem was solved. I used the jig Vans provides to find the neutral point for the bellcrank and made sure the servo arm was at a 90 degree angle per the instructions. I maneuvered the torque wrench in there to tighten everything down and applied torque seal.

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.

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.

Did a bunch of miscellaneous finishing work on the wings. Took the tank off the right wing and torqued the tie down bolts and dabbed them with inspection laquer. Tapped on a few skin rivets that weren’t set enough. Drilled out a couple of bad rivets and re-set them. Put both tanks back on. The left tank fits after sanding down the ProSeal. Yeah! The wings are back in the cradle and going to stay there for a while. I’ll do the bottom skins at some future date. For now, I’m done messing with the wings.

Positioned the flap and drilled out the wing side of the hinge. Since the instructions on doing this are a little sparse, this is what I did. Use side cleco clamps to hold the hinge in place.

Position the aileron to the neutral position. I did this by lining up the tooling holes in the end ribs. I jammed a towel between the flap and the wing to hold it in position. It doesn’t have to be exact. Next adjust the flap so that it lines up with the aileron. Then start drilling the hinge starting at one end. Put a cleco in every hole as you drill to hold the hinge in tight.

You’ll find that the flap brace doesn’t stay lined up with the wing skin very well. I used a couple of rivets to line up the holes and keep it aligned while I was drilling.

After that, I disassembled and deburred everything. I clecoed on the hinge to countersink the flap brace.

And finally, I dimpled the flap brace area of the wing skin and primed the scarf area.

Finished the right flap!! Julie helped me rivet the spar to skin rivets under the curl and I squeezed the rest of the rivets. It’s nice to finally have that thing done and off of the bench.

Julie helped me rivet most of the right flap. This one went much easier than the left flap. We almost got it done in one session, but we started having problems with the front spar rivets. Better to wait until tomorrow rather than screw up a dozen rivets.

I also pulled the spar to rib blind rivets.