Dave’s RV-7A Building Log

Previewed the instructions for the rudder and stared at the stiffener stock, trying to figure out exactly where the cuts go.

Dimpled the holes in the VS skin. Used the squeezer around the edge and the C-frame in the middle.

The last work item before priming the VS parts is to make the lightening holes in the rear spar doubler. Then I wait for good weather.

Julie helped me knock out the rest of the rivets in the field of the HS today. I cleco’ed on the rear spar, and squeezed the rivets around the outside, except for the rear spar rivets. I want the EAA Technical Advisor to be able to look inside the HS, so I’ll leave the rear spar until after he comes by.

I was pretty successful with the squeezer. I had to drill out the first rivet I set, but was more careful after that. You just need to make sure the squeezer is parallel with the rivet. Since I just received the no-hole/thin-nose yoke Friday, I used that for the rivets way in the leading edge. I then left it on and did all of the rest of the rivets with it. That’s a pretty handy yoke.

Very cool to have the HS basically done.

Deburred holes on the VS skin. Didn’t build last night, as I was at the local EAA chapter meeting. Looks like a good group.

Started prepping the VS skin. Smoothed and deburred edges of the skin. Removed the plastic from the inside and along the rivet lines on the outside.

Prepared VS ribs and spars. Such a simple phrase, but it takes so long. I disassembled everything, then deburred all of the holes in the ribs and spars, followed by smoothing and deburring the edges. I dimpled the holes for attaching the skins and for the area on the rear spar that attaches to the fuselage. Counter-sunk the holes in the lower rear spar stiffener. Also smoothed the edges of the stiffener, which took a while.

This shows how the bottom of the rear spar and stiffener are dimpled and countersunk to allow for flush head rivets where the VS attaches to the fuselage.

Drilled the VS ribs to the spars. Clecoed on the skins and final drilled the skin to the ribs and spars.

Finished riveting the left side HS. Started on the right side. From Dan C’s site, I got a tip to put duct tape on the corners of the bucking bar. That kept it from marring the neighboring ribs. I also read on the rv-list that putting riveting tape over the heads will keep the surface from getting marred. Both tips worked great. Marring the surface is not a big deal, since I plan on painting the plane in the end. I just want it to look the best it can while it hangs from the rafters for months. I also ordered a swivel mushroom rivet set with a rubber guard. That will help too.

Clecoed together the VS spars and ribs. Drilled out the hinge brackets and the rear spar stiffener. I can already tell this part is going to be a breeze compared to the HS.

We’re riveting! With Julie’s helped we did all of the field (i.e. can’t reach with a squeezer) rivets on the bottom side of the left HS. It took a fair amount of monkeying with air pressure and the regulator at the gun in order to get the right combo. We used 80# at the compressor outlet and about 1/2 closed on the gun regulator. We practiced a bit on a piece of scrap until Julie felt she had the timing down pretty good. She generally would shoot for 3 seconds. And then I’d signal whether it needed another 1/2 second by visually looking at it. And then I’d follow up with the gauge after a whole line was done.

The rivets turned out better than I expected. It wasn’t nearly as hard as I thought it was going to be. I did have to drill out one rivet. I let the bucking bar slip off the shop head. Julie was so understanding, “It’s nobody’s fault.”

I had a tough time getting even the small bucking bar into the small space inside the HS. I ended up polishing a spot on the side of the bucking bar–easily done with the grinder followed by Scotch-brite.

We also shot the two 470AD4 rivets that hold the 702 and 706 together, per the instructions. That took more adjustments with the rivet gun, since they’re a bigger rivet. It was also hard for Julie to keep the gun on the round head (vs. the flat heads with the 426AD3 rivets on the skin). She did a great job, though.

Big day. It’s starting to look like a real airplane part!!