Couple nights worth of work to log. After getting a good review of my work from the tech counselor, it was time to start the final riveting of the skin to the frame to include all sections.
Spent a few hours the first night completing the rest of the interior rivets with the rivet gun and bucking bar. I experimented with a couple different ways to protect the internal structure from the bucking bar. Tape only was not enough to keep the bar from marring the surface. Eventually I settled on a small piece of scrap about 3"x2" to use as a shield on top of the tape. This ultimately did the trick and once I started using that along with the masking tape, I was no longer scuffing up the ribs and spars, all of that damage was occurring to the small piece of scrap. So good lesson there on how to deal with that. I did finally manage to mangle one rivet which considering how many I'd set over the past few sessions, I was almost relieved to know that it's still possible to screw up the -3 rivets.
Fortunately one of the points of discussion with Gary from the tech inspection was how I was going about removing rivets. In talking with him I realized I was making my life a lot harder doing it the way I was doing it. For a while now I have been drilling all the way through the rivet and then trying to work the heads off before popping the rivet out or drilling the rest of the rivet out. With Gary's advice this time I only drilled down to depth just slightly below the head of the rivet, in this case a flush (426) rivet. With that done I was able to pop the head off fairly cleanly revealing the shank of the rivet but more importantly preserving the original hole size. I simply used the #40 bit to drill out the rest of the rivet and I was able to use another -3 rivet and finish it off no worse for ware. So thanks Gary for the suggestion, it worked a lot better this way. Always learning!
Anyways finished this night with all of the interior rivets set and by test fitting the rear spar to the rear of the stab. WHAAAAAAAAAAAAAAAT!!!!!! It didn't fit!!!!! What the @#$$ ???? Much to my chagrin, the rear spar was about a 1/4" short of fitting properly from one side to the other. I started to get that sinking feeling in the pit of my stomach that somehow, someway, after all this time and effort, after being so careful that somehow I had managed to dork this up. I tried multiple times to cleco the rear spar in only to see that it just wasn't fitting like it should on one half. I could see that the middle of the rear spar was not aligned on the centerline of the piece. Kinda started to panic here a bit until I slowly nudged the short side of the spar into place.
All in all it wasn't screwed up after all. Like a lot of the pieces, it just needed a bit of encouragement to fit into place. The aluminum is forgiving in places and this was a case of just tightening up the skin to match the structure. So crisis adverted! Whew! It finally fit and all that worrying was for nothing. Again lesson learned. So the night ended with the rear spar cleco'd into place and ready to be riveted.
The following evening gave me a chance to relax a little from the violence that is riveting with a bucking bar and gun. All of these outside rivets can be done with a squeezer. I started out with the intention of using the pneumatic squeezer but quickly realized that due to its weight and shape, it was going to be more trouble than it was worth to use. The small -3 rivets are fairly easy to squeeze with a hand squeezer so once I got the depth dialed in, it was off to the races and I set all of the top side rear skin rivets without issue. I ended by riveting the majority of the tip rib top side rivets as well. I went as far as I could with the yoke I was using on the hand squeezer. Gary mentioned during the inspection that I may have to use a pair of vice grips for the last few rivets as there isn't enough room to get a bucking bar or squeezer yoke in there. We'll see what I end up doing, done slowly and cautiously, I can probably set those few with a small bucking bar.
By the end of the night it's starting to look like a completed part!
One final bit I wanted to mention is that at the end of the previous night I stopped and looked over the assembly drawing to make sure I had completed all of the tasks that are called for on the drawing (most are not mentioned in the plans). I came across one task that I had neglected to get to yet. This task has you leave 10 of the top side interior rivets empty and unfilled to make room for (eventually) nutplates to hold the empennage fairing in place. It's a good thing I caught this because I was all set to rivet these holes in the coming days. However the instruction left me a bit confused so I asked the question on the Facebook Vans builder group as to whether these holes were really supposed to be left without being riveted. As always you get about 5 or 6 different answers and you have to sort out who is most likely correct or who has the best advice. The answer is that "yes" these 10 holes are supposed to be left blank and eventually nut plates will use these holes to make room for the empennage fairing waaaaaaaaaaaaaaaaaaaaaaaaaaaay down the road when you get to that point. However I have seen and several people on that post mentioned that this is not a very good way to secure that fairing, that there was a better way. The 'better' way is to go ahead and rivet these 10 holes like the rest of the skin and instead, form the empennage fairing in a different way and thereby secure it in a different way that avoids using nutplates at all. I have seen that on other builds and that's what I intend to do so asking the question definitely paid off. I will go ahead and rivet those holes and attach the fairing differently than what the plans call for.
This is a great example of tying to think ahead, far ahead in this case, about how you will ultimately complete the airplane way down the road and how some things that you are doing here at the very beginning can affect that outcome years from now. Gotta be careful about how you do some of these things so that you don't paint yourself into a corner a few years from now.