I was right, it took us 3 work sessions to finish riveting the ribs to the skin. I continued to use the long, steel bucking bar and it worked great!
Everything went very smoothly, it just took time. Here we are one quarter done:
And here is one side completely finished and without rivets!
That probably doesn't seem very exciting, but the last time there were no rivets in the skin was when we first put the skeleton and skin together in August. We were also able to remove the wooden cradles we created back in June. It was really nice not to have to deal with the cradles because they tend to slide around on the bench. We used some small pieces of foam between the horizontal stabilizer and the workbench to cushion everything. The bad part about losing the cradles was that it lowered everything by a couple of inches, which meant I had to bend down farther when we were riveting. You wouldn't think that a couple of inches would make much difference, but it was a lot harder on my back and neck.
We finally finished riveting the skin to the ribs this morning. Mike decided to show off his best Vanna White moves.
The whole thing is surprisingly light with no clecos in it.
Our next task was to go back a few steps and finish riveting a rib to the front spar. When we first worked on this step many months ago, the directions suggested these rivets would be easier to access once the cradles were out of the way.
I'm going to tell you right now, the cradles are not the problem. The problem is that this space is practically inaccessible. Here's what the instruction manual shows...
And here is where you're actually trying to work...
I put my hand in the picture to provide some sort of scale. You can just see the empty holes and ends of the clecos next to my index finger. (The fact that my fingernail polish matches the blue vinyl is a nice bonus.) These rivets are between the two halves of the horizontal stabilizer (right in the middle where the skin doesn't cover) and between the front spar and the horizontal stringers. My hand is pretty small and I estimate there's about six inches between the stringer and the spar. There's practically no room to work in there and because everything is at a funky angle, most of our tools wouldn't reach either.
The rivets wouldn't quite fit into the holes, but Mike couldn't use the regular drill bit to ream the holes. The normal bit he uses in this situation is specifically shaped so it won't enlarge the hole, just remove any tiny chips of metal that might be blocking the rivet. Instead, he had to very carefully use a really long, regular drill bit and try not to enlarge the holes .
We tried to figure out a way to squeeze those rivets, but there just wasn't enough room. Mike had to use the offset riveter and I had to revert to my tungsten bucking bar because it was the only thing that would fit in that tight space. There are so many other rivets in other pieces in that area so I also had to be careful to not accidentally damage those. To top everything off, we were using size 4-8 rivets, which are bigger in diameter and a lot longer than what we've been using. I didn't take many pictures of us trying to install these rivets, mostly because I was too busy swearing and feeling frustrated.
My hands and knuckles got banged around a lot and it took us about 45 minutes to put in 10 rivets. At one point, Mike actually ran the rivet gun and the bucking bar on his own because that was just easier.
We managed to get it done, but not without one major screw-up.
That rivet is definitely a problem. One side is basically pounded completely flat against the rib flange. It will have to come out, but that is not going to be an easy task. Normally we would drill out the rivet head and punch the shaft out the other side. Since we can't really identify the center of the rivet head, that probably won't work. We decided to leave it for now so Mike can think about the best way to get it out of there without doing serious damage.
We ended the day by (finally!) clecoing the rear spar into place. We officially have no more loose parts for the horizontal stabilizer!!! We need a few more pop rivets to connect the rear spar to the ribs and then we can rivet the skin to the rear spar.
Finally, I hit a very exciting milestone today. I have personally put 100 hours into the build. Mike has put in a lot more solo hours and hit the hundred hour mark months ago. I've been patiently watching as my total hours crept upward and hitting 100 hours feels like a pretty great achievement.