1977 Super Decathlon 8KCAB Rebuild

Bartman

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hard to tell, there are rings showing in the flare, probably just lighting. I use scotchbrite pads to clean those faces up. I turn the flare tool down until I get that "sharp rise in torque", then back out and in 2 or 3 times. makes me feel like I get a nice even clean flare with over doing it.
That’s the trick, not overdoing it so there won’t be a thin spot where a crack/leak can start later.
 

Bruce

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That is factory mine originally went behind the pedals and was dented so it’s been relocated.
 

Bartman

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Finally making a little progress, the aft fuel lines are in and the fear of breaking everything I touch is subsiding!

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Bartman

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Fuel and vent lines are all in. Took way longer to figure out where to put them than it did to fit them. 🤬

If anyone sees anything that can be done better, please chime in. Thanks!

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Bruce

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That looks great, we’re u a engineer in a prior life? The only thing I see is where fuel Lines come through bulk head I might put a rubber hose around so no rubbing but there may be clearance there I’m thinking mine were centered. Hard to tell if they touch from shot. One thing I would do different next time is before the fabric application is to run some cloth over anywhere fabric might touch the structures for any small points. I had several spots wile sanding that made pinholes most I could patch from backside. This being my first if I do this again the next will be much nicer. I’m just going for a solid flyer and I like things to look nice.
 

Bob Turner

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That is why surface tapes are so important. Always tape anything that touches structure or a former, or could touch when applying pressure.

Oops - I think this got tagged to the wrong thread?
 
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Bartman

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don't quote me on this but I think factory puts a zip tie around the fuel line first before putting a second that holds it to the frame. the first zip tie bears against the frame tube in the way you guys said something else might be there for protection. the main line that goes from the rear manifold to the header tank has a fuel tubing sleeve over it in two places where it passes through formers. and yes, I was an engineer in a past life but don't hold that against me! lol. I have to be anal about all of this if I am going to post pictures! thanks for the replies.
 

Bartman

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I didn't nail the centers of those holes in the formers but there is enough room to keep it from rubbing. My IA may ask for a bit of hose or something over the tube there, I'll look at it again.
 

Bartman

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Moving on to getting the cockpit controls assembled, there's an interesting note in the Decathlon parts manual that says castings, like the stick sockets, have to be radiograph and penetrant checked for cracks and then marked blue and stamped with an X, P, or Z. The other parts that have this note applied are the aileron control bellcranks in the fuselage, the aileron hinge/bellcrank assemblies in the wings, and the yoke at the rear of the torque tube. When I first went through the parts I just thought they all had overspray on them! Here are pics before/after using some Spray 9 and red scotch brite on them. Given that the 8KCAB castings need the extra inspections I gotta think I'm lucky that the parts that came with the project are all usable!

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Bartman

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trim lever is all jazzed up and back in the frame with new cables and leather drag washers.
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here's the detail as to how the stack of washers and stuff are installed
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this is what washer 1-2380 looks like (usually plated, not primer and rusting, it's from my spares bin). it hooks onto a tab that protrudes from the mounting arm on the frame.
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Bartman

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Given that the 8KCAB castings need the extra inspections I gotta think I'm lucky that the parts that came with the project are all usable!
I spoke too soon, had to order a new aileron control yoke for the torque tube today. After getting the bearing off it looked like either there was wear or I was too rough with it getting the bearing off. A new assembly with a new bearing installed was about $130, not too bad I guess.
 

Hiperbiper

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Doesn't the headliner need to go around the two tubes you have the fuel lines zip tied to?
The only other thing I would add is always clip the zip ties flush with the receptacle...those sharp little ends draw blood and poke holes in stuff .

Chris
 

Bartman

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yes, that's where the headliner goes. i just taped it there to keep it from poking me in the eye while I was fitting the other tubes.

I leave a little tab so I can pull them tight again if needed but they'll be clipped before the fabric goes on.

thanks for having a look at things.
Bart
 

Bartman

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Doesn't the headliner need to go around the two tubes you have the fuel lines zip tied to?
The only other thing I would add is always clip the zip ties flush with the receptacle...those sharp little ends draw blood and poke holes in stuff .

Chris
I might have misunderstood which tubes you were talking about. which tubes were you talking about?
 

Hiperbiper

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The tubes I was referring to go from the rear spar carry thru back to the first tubing cluster...
The ones your fuel lines are tied to.
On the 7AC the headliner attaches to them:
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20200723_174250.jpg

Chris
 

Bartman

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I found this photo that shows those tubes are not used for the headliner but you get extra credit for actually looking at the photos! I also feel better seeing that the factory didn't exactly nail the center of those holes with the fuel lines.


Being that I didn't take the plane apart before trying to put it back together it's inevitable that I'm going to have to backtrack at some point after getting the assembly sequence wrong. It's still early, hopefully I won't dork things up too badly but it's bound to happen.
 

Bruce

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So your telling us you like life size puzzles🥸I took mine apart 2 1/2 years ago and not sure if I rember where all the parts go. I keep picking up things and think “what’s this” so looking forward to meeting some of you guys maybe a meet up at Airventure