Ok, so it’s time to begin the infamous Section 29 – Side Skins. Going into this I’m already worried as there are a few new skills that I’m going to have to learn with little room for error. Bending the Longerons (yes, I did do a little of this on the Tailcone), and bending the fuselage skins themselves. No reason to drag my feet, let’s get past this and move on!
So the very first step is to bend the longerons. With memories of bending the longerons on the empennage, I decided to purchase a set of bending dies from Buller Enterprises. While not cheap, I figured they were worth a shot and I may be able to sell them at a small discount or donate to our EAA chapter tool crib. I’ll say that I’m happy with the bending dies. They worked as expected and made very quick work with bending the longerons once I got the hang of things.
With the mid-fuse longerons bent, I was about to drill the holes per the template, only to realize I bent both longerons the same way. UGH!! Remember I mentioned that I was happy I purchased spare angle aluminum? This is why! After checking I had enough spare, I went ahead and cut another longeron and correctly bent it the correct direction. Then, it was on to drilling the holes per the template.
With the mid-fuse longerons done, I moved to the fwd fuse longerons. I stressed myself out more on these as I really only had 1 shot to get these right (without costing a lot more to get a replacement shipped to me). Luckily I had sufficient practice and these went without a hitch. (I did remember that the Right and Left longerons were very different lengths!) I then also driled the holes per the templates in both of these longerons and proceeded to twist the ends of the longerons per the plans.
Then it was onto another new skill. Bending the side skins. Once again I was lucky that Todd Stoval had provided me his bending jig for my use. One less thing for me to create and I can pass it along to another builder in our chapter once I’m done with it. First thing I had to do we get more c-clamps from harbor freight. With those purchased, I then began to bend the skins ever so slightly. Honestly I was a weenie at first. After double checking other builder logs I realized I really needed to put my weight behind the bends. That really made things move along nicely. By the fourth skins, I felt more like a pro and was able to quickly bent things into position.
With the longerons and the skins ready I then assemble and drill the seat back brace and the baggage door seal angles. Pretty straight forward all things considered. Cutting down the door seals was interesting, but easily accomplished. I actually like some of the fabrication side of the build.
As I go to start installing these parts on the fuselage, I found myself getting really excited as this really starts to look nice. Then it’s on to match drilling. One thing that had me doubting myself was the drill lines on the longerons. I drew the lines at 5/16 per 29-2 Figure 1 on all the longerons and that worked well.
I borrowed an angle drill from Jeff Karrels to drill some of the holes in the longerons due to the tight spacing. After a day with this drill I decided I really needed to get one of my own. The only issue I found was with the right mid-fuse longeron where it connects to the F-1050c brace. My first attempt left the edge distance a little off for me. After checking my aluminum stock, I realized I had enough to remake yet another longeron. 10 mins later, I re-drilled and was much happier with the result. Only issue was I was a little to far off in the other direction. Decided that a thin shim would correct the situation and prevent distortion on the skin.
Lastly before I wrap up this update, I put the appropriate twist in the Fuse Channels. Only recommendation here is sand/round the corners of the wooden spaces you use.