Changing course and working on the tail

So…after thinking over my next move quite a bit, I’ve decided to change up what I’m working on. Originally my plan had been to try and get the canopy cutting done this fall, before winter set in. The idea there is that cold temperatures increase the chances of cracking the canopy ($$$), and I figured otherwise I’d likely be getting to the point of canopy work sometime around the coldest part of the year. Thing is, at this point I’m a good month or more behind where I thought I might be, so rethinking things isn’t totally out of line.

What really pushed me in this direction was considering what I’d need to do to work on the canopy bubble. Broadly, there are two parts of the cutting portion of the program: first, the entire bubble gets progressively trimmed until it fits on the fuselage and frame correctly, and second, the bubble gets cut into two pieces, forming the windshield that gets affixed to the roll bar and forward upper skin, and the bubble that get attached to the sliding frame.

After doing a decent amount of reading on this work, one thing I really want to do is to attach the uncut bubble to the roll bar before cutting, to better ensure a really good fit. But I can’t do that until the forward upper skin is permanently riveted in place, and I’m nowhere near ready to do that. So that means either I don’t attach the bubble beforehand, or I don’t make the big cut right now.

Even setting that decision aside, no matter what I do right now I still have to put the canopy back in storage for a while after trimming and/or cutting. And honestly, I think I’d feel better just storing it as-is instead of after trimming, when I feel like it might be even a slight bit more prone to cracking unless I support it really carefully. Bottom line, I don’t think there’s a real need to try and rush into the canopy work right now, and I don’t see myself making such rapid progress that I’m at a point where I need to be cutting it any sooner than, say, next March, maybe later.

So, what to work on instead? I could pick back up with the wiring inside the airplane, maybe working on the stick grip wiring, but I think I need the control column in place before I can really do that, and with that installed getting in the fuselage and moving around is a little tougher. Instead, I decided to start thinking in terms of closing stuff out at the tail and working my way forward. This means permanently attaching the empennage, reinstalling the elevator control system, and maybe even moving on to fiberglass work, depending on how things progress with my engine order.

So that leads me to tonight. I figured I’d try and work on really attaching the horizontal stab, but first I needed to remove it again. I never did permanently install the two elevator control stop pieces I worked on a while back, and getting that riveting done would have been somewhere between difficult and impossible with the stab mounted. So I pulled that off, set it aside, and got the two stop pieces riveted (and, in the case of the aft stop, bolted) in place.

Next, I reinstalled the stab, this time inserting brand new bolts that I ordered specifically for final installation. The four bolts that attach the rear spar to the vertical stab bars were easy enough to torque, but the four bolts that drop in through the forward spare and down into the fuselage are another matter. Torquing these, I think, has to be a two-person job, with one person working inside the tailcone. If I contort my hand really carefully, I can touch the bolts inside the fuselage, but doing anything like starting the buts or operating a torque wrench isn’t happening.

I did decide, however, to see about crawling back into the tail and at least starting the nuts. I was under the impression that accessing the bolts that way would be no fun at all, but it turns out to be physically impossible as far as I can tell. I could probably do it if the ADAHRS mount wasn’t back there, but that’s riveted in place now and removing those rivets would be tough to do without causing damage. So I think I’ve got no choice but to find/bribe a very small person to crawl in there and help me out with this.

So that’s where I finished the night. Thing is, I’m kinda stuck until I get those bolts installed, since the next steps I’d be taking would involve adding even more stuff back there, and probably starting to remove the backboards that I lay on while crawling into the cave. Or maybe I’ll try going back out, inserting the bolts from below, and installing the nuts above. That might be doable, and wouldn’t require trusting, say, a neighborhood kid with properly torquing fasteners that attach an extremely critical piece of structure.

We’ll see, I guess.

Update: Well, my idea worked out fairly well. I was able to get three of the four bolts inserted from below, working through the aft deck, and I got those four torqued as well. The last one is proving to be a real bear to get the bolt inserted – that’s the hardest part. If i could get that done I’d be pretty much home free. Maybe I’ll give that one another try tomorrow evening, for tonight I’ve had my fill of contorting my arm and wrist.

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