The Barn Find Build

[avidflyer]

I wouldn't think you need to pull the rivets. I would just wash off all the grease I could, move the tube, and do it again. Keep at it till the grease is gone. I think I would make some provision so that the bushing can't move out of it's location. JImChuk

[Eric Page]

Sorry, Jim, I saw your comment about the bearing coming out and forgot to respond. I don't think mine is going anywhere, as it was installed with Scotch-Weld. I've tried shifting that stuff with everything up to a propane torch and had no luck.

[Eric Page]

Well, a couple more days of life happened. I spent one of them under my parents' house, repairing HVAC ducts that were chewed up by rats. If they can get to warm air, they'll chew a hole big enough to put your fist through. This is an 18" trunk line coming out of the furnace manifold, and the amount of hot air being lost into the crawlspace was impressive.

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Check your crawlspace vent screens, people!

Anyway, this isn't a pest control forum...

I did another day of work sanding and filling the horizontal and vertical stab tips. I started out with this.

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Then I formed it with a wood rasp to get this.

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Then I sanded it with 100-grit to remove the rasp marks.

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And finally sanded with 320 grit to eliminate the scratches.

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There were still a few small divots and scratches left, so I mixed and applied a coat of SuperFil.

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I'm not 100% certain, but I'm pretty sure I screwed up the SuperFil mix. The first batch I neglected to stir up the gunk at the bottom of the jar that had precipitated out of the hardener, and the second batch I think I mixed at 1:1 instead of 1:2. Good thing this stuff is only cosmetic! In any case, both batches have hardened just fine.

On the vertical, I followed the same procedure of rasp shaping, sanding and SuperFil.

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While I had the SuperFil out, I took care of the areas around the door openings and rear quarter windows where the aluminum angle overlaps itself and leaves a small step edge, or where there were small voids.

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Next up I got started on tips for the new elevator. I began by cutting two pieces of rigid insulation foam a bit wider and a few inches longer than needed.

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Then I used 100-grit wrapped around the handle of a small pair of pliers to sand a channel in the foam to receive the steel end tube of the elevator, and cut away a bit of foam at one end to make room for the end of the elevator's spar tube.

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Finally, I mixed up some Hysol and glued the foam blocks to the ends of the elevator.

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[bbs428]

LOL - yes life happens and critters can do a lot of damage!

Tips are looking good!

[Eric Page]

Had my FAA medical today. I made it to one week short of my 50th before I got stuck with, "Must wear corrective lenses." Grrrr!!!

Another round of sanding this evening. The horizontal and vertical stab tips are getting close.

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It's hard to tell from these photos, but this one is a little lopsided; the lower half is a bit "fuller" than the upper half. I did another layer of SuperFil (mixed 2:1 this time!) there to see if I can get a more uniform shape.

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Both ends of the horizontal also got more SuperFil around the leading edges. I'm hoping to get a better transition from the tube to the end rib.

I'm quite happy with the shape of the vertical tip. Like the horizontal, it needs some work at the leading edges, as well as the right side of the trailing edge. I applied more SuperFil there as well.

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Finally, I sanded the areas around the doors and rear windows where I had applied SuperFil. They mostly turned out fine, but I added a bit more in a few places to smooth out some rivets that were set a little poorly.

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[jiott]

You guys are doing a fantastic job on smoothing those tips. Just in the interest of saving some of your time may I say that all those areas that get covered with fabric, most get 3 layers, are far less needful of perfectly smooth (paint grade) finish than say a fiberglass or aluminum area that gets painted only. Scratches and small pits will never show thru all that fabric. I am not suggesting poor workmanship by any means, just maybe a little time-saving realism. That said, I also was caught up in obsessive perfectionism on my project just because it felt good on my baby. Of course it is better to overdo something than just let it slide by. Looking good guys!

[Eric Page]

That would have been great advice three days ago, Jim! Just kidding -- I figured that was probably the case, but I think I'm doing it just to prove to myself that the first builder could have done it right but just chose not to. Anyway, I'm nearly done with the stabs and should be able to finish up the elevator within a couple of days.

[Eric Page]

More work on the vertical and horizontal stab tips today. I'm mostly happy with the vertical; it just needed another dab of filler on the right side to get the transition I want from the forward tube.

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The horizontal tips are now dialed in just how I wanted them. The first photo looks a little lopsided, but that's due to camera angle.

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The aluminum angles around the door openings and rear windows are getting really close. The right side is good, and I smeared a bit more SuperFil on the left side.

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I got to work on the elevator tips next. First I used a utility knife to cut away most of the rigid foam, leaving a very rough shape, then used a block with 100-grit to shape it closer to what I wanted. This left some voids at the leading and trailing edges, but those were easily filled with a few grams of SuperFil while I was coating the rest of the foam. These will get sanded (and probably coated again) tomorrow.

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Some hardware arrived a couple days ago from Spruce, so I finished assembly of the notched rudder pedal adjustment brackets.

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I really wanted to keep moving on installing the controls, but I'm stuck until I get the floorboards re-varnished. I did get the rudder pedal adjustment handles fitted, which required relieving a little metal from the bottom of one handle so it didn't foul on the fuselage tube. That got a shot of primer/paint before being installed.

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Final task today was getting the grease removed from the mid-fuselage push-pull tube bearing. There was just enough room around the tube to slip a piece of paper towel in there, so I was able to get virtually all of the grease out without too much hassle.

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[alexM]

Remember way back when you looked at the pile of parts and read the manual and thought it was way too vague? It's funny that as you proceed through your build the statement "slap some s*** on there and sand it to a pleasing shape" makes complete sense.

When I started with my horizontal and elevator they were mounted to the fuselage. I got as far as bonding on the balsa, rough shaping it and gooping it up with SuperFil before I realized it would be much easier if I hung it with the leading edge straight up at eye level so I could sand the it symmetrically. Once I had the basic shape, you know, pleasing I took the stab/elevator apart so I could smooth out he joint between them.

[Eric Page]

Very true! I'm doing just the opposite; some time pretty soon I'm going to have to connect them together to be sure the shape on the elevator matches the one on the stab.