First though I looked at the Proseal results from yesterday. The steps were successfully sealed although I will probably add another thin layer of Proseal on one of the steps next time I have to mix some more of it as an air bubble got caught and I can't see if it would provide a path for water getting into the step. So I'll just cover that bubble up next time.
The left one in this picture is the one with the air bubble.
Then I went ahead and added the optional nutplates for the VHF antenna installation on page 21-16. This required match drilling holes with the K1000-08 nutplates that are supposed to get used. I haven't had to do this so far, so I experimented with it, knowing that the result would be on the belly as well as probably covered my the antenna mounting plate.
The clamp and my thumb were holding the nutplate in place while I was drilling with my free hand. Once one hole has been drilled, I could insert a cleco to hold the nutplate supported on one end.
That didn't turn out so perfectly as I wanted it to be. The problem is that the nutplate does move a bit as it is only firmly supported on one end. To stop this from happening I did two things. I drew a center line through the screw hole and beyond to mark on which line the rivet holes should be, so the adjustment of the nutplate would be easier and I drove a screw through the nutplate from the opposite side which would support the nutplate in the screw hole a bit during drilling.
This worked much better even though the clamp couldn't be placed on the center anymore. Still the nutplate was easy to hold in place while drilling the first hole and after the cleco was set it was much easier to ensure that the nutplate wouldn't turn while drilling the second hole.
After drilling and deburring the holes, the next task was to dimple the holes. While this would have been very easy before putting the skin on it became almost impossible afterwards. Although the access holes in the belly skin would have provided enough room to get the squeezer through to do the job, the stiffener left and right of the antenna attach point would have interfered with the yoke of the squeezer as the dies are not long enough to ensure clearance. In order to dimple these holes anyway I had to get dies that get used with a pop riveter.
These dies have a dimple form carved into their surface and use a simple nail as the mandrel that gets pulled by the pop riveter. If you're careful and use a hand riveter to can even dimple multiple holes before the nail breaks. The only thing you have to worry about when using them is to put the right die on the right side of the skin.
After a few minutes all the holes were dimpled to receive CCR264 rivets and I could put the nutplates in place.
Since my drill out experience with this type of rivet I learned to be extremely careful and focussed when riveting them to make sure I never have to drill one out again. So it took longer than usual but it looks perfect, if I may say that.
Then it was time to work on the other side of the skin while the fuselage was still on its side. This was to insert those 6 screws and tighten with the nuts I had just recently acquired the necessary deep 7/32" socket. My wife was up to the task and except for one slightly resistant nut all of them went in without any problems.
And this concluded the tasks of section 21. So on to the last step in section 22 then ...
... which was to attach the forward lower fuselage to the mid section and riveted it in place. That was not easy at all. The instructions didn't give any hint as to how the best approach connecting those two large and heavy parts to each other, so it took some consideration and creativity to come up with a good way.
I know that Dave did it with the fuselage upside down and he experienced some problems because of the way how the skins overlap. That led me to the idea of trying it while the fuselage is on its side. That way I could walk around and fiddle with the overlap issues on the inside if necessary.
It still is awkward as you have to support the forward part which tapers significantly to the front to allow some of the weight to rest on the bench while you try to align the holes. I'm not even sure if a second hand would help so much as most of the problem was to find out where it interfered.
Anyway, after a full hour of fiddling, thinking that I got it, removing clecos again as I had a bad overlap and doing it again, I finally succeeded and had those two parts correctly connected.
A lunch break and some riveting action later, the parts were attached for good. Make sure you rivet the vertical flanges (inside the cockpit) before doing the skin as the rivets might otherwise interfere. Still there are some rivets in the skin center that wouldn't go all the way in as Van's had you already install the snap bushings and they are in the way. A good way of pulling these is with the manual puller and applying a lot of pressure while slowly pulling them.
And then I turned it over to get the real look of an airplane.
Well, it might look much like an airplane to you, but I can definitely see it already ;-).
So, now I have to decide which section to work on next. I think it'll be the fuel line installation, section 28, as this is a good time to do it and I am a bit afraid of the longeron bending that would start with section 23.
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