Dave’s RV-7A Building Log

Started riveting together the firewall. I’m using the squeezer wherever I can, following the tips on Dan C’s web site. I took it real slow, because I don’t want to drill out any of these rivets.

Every rivet call-out on the plans so far has been on the short side. I used the called out size along the bottom, and the shop heads are barely large enough. I used the next size up for the rest of the rivets, and they are setting fine with not even a hint of cleating.

I have all of the rivets on the sides squeezed and most of the rivets along the bottom. Now I’m to the point where I need to back-rivet.

Clecoed together the firewall.

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.

Cleaned and primed the firewall parts.

Since the firewall parts need to be primed and the weather isn’t cooperating, I pulled out the parts for the F-704 center section bulkhead. They are very cool looking, solid and anodized. I carefully located and drilled out the holes for the snap bushings. Next, I clecoed the parts together including the spacer bars and put in the close tolerance bolts. Those things are a tight fit. I put them in the freezer first, but I don’t think that helped.

Next, I drilled all of the rivets holes to full size. I actually had more trouble getting the close tolerance bolts out, because the web was pulling away from the bar. Once I clamped that tightly together, the bolts dropped out pretty easily.

And finally I deburred all of the holes.

On Dan C’s web site, it says the fuselage instructions are sparse. Van’s must have updated them, because the instructions I have a pretty detailed so far. The funny part is they left out one important part. In the section called “Assembly of F-704 bulkhead”, nowhere does it say to rivet together the F-704 bulkhead. Must have been an oversight.

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.

Deburred the rest of the firewall parts, dimpled the stainless steel sheet, and countersunk everything that needed it.

Finished final drilling the firewall, including the floor brackets and the recess. A couple of the holes on the recess didn’t line up very well, but it’s not a structural part. I just drilled them out, leaving them a little oblong.

When I took the firewall apart, I marked which parts need to be countersunk. It won’t be obvious once everything is apart.

I started deburring the firewall after that. The thin stainless sheet deburs almost like aluminum–just a little tougher.

Final drilled most of the firewall. This was a pretty easy step. I used Boelube and kept the drill speed low. One of the corner angles was super powdercoated, so I had to use silver clecos in the holes temporarily.