Cessna 120-140 Association

Considering looking at a 140 that was last recovered 56 years ago according to the owner and sometime in the 90s rejuvenated. I have not looked at the logs to confirm either. Sooo
What can I expect internally of the wing structure, assuming it's been kept inside? What should I look for? Where?
What are the possibilities that a new to the plane IA would be willing to sign off an annual? I realize I would have to approach him. (the IA)
Approximate cost in material for a wing recover, including epoxy primer for the internals? I do the work with supervision.

Also, what is the opinion on return costs of installation of an alternator and light weight starter. Guess what i'm asking is how much would it increase the value of a 120/140?
Thanks, In the looking stage.

What was it covered with? Is it currently, or was it recently airworthy? "Rejuvenated" means many things to many people. Technically (I think...) it means the top coatings were dissolved and allowed to "reflow". If it was covered with polyester fabric (Ceconite, Stits, Polyfiber, etc.) and stored inside it could still be airworthy. I'd want to get a real good look at the structure inside, though, before signing it off.

I'm too out of touch to help with the price. There are several good options out there. I'm partial to Polyfiber as that's what I have the most experience with, but my school recently started teaching the Stewart system, which is "non-toxic". Seems to work fine.

Personally, I wouldn't install a light weight starter or alternator unless the ones you have need to be replaced anyhow. You will never get your money back on resale. Two otherwise equal planes, one with a light weight starter and the other with an original will be worth the same amount. The alternator may command a slight premium over a 20 amp generator, but not much, and it depends a lot on the intentions of the buyer (night flight in controlled airspace vs. day VFR).

If you have any questions on whether your IA will "annual" the airplane, simple, have him/her annual it as a pre-buy. Or at least look at it first.

You'll want really good records. Full log books back to day 1 are preferred. Also very important is full documentation of any repairs and alterations. Are the 337s', STC's etc with the current paperwork so you don't have to dig them out.

Polyfiber is my choice of wing coverings, Like John, that is most of my experience.

Wings take about 40 hours per wing to strip and re-cover. That gets you to primer/UV-block stage. Top coat is extra as are any repairs(I would expect some) to the underlying structure.

So at a minimum 80 manhours X shop rate. Plus materials. Any good polyfiber dealer can quote you enough material, paint supplies etc to cover both wings. My guess would be several grand, but I"m out of touch with current prices.

If it was recovered 56 years ago, dollars to doughnuts it will need a recover.

How long ago was the engine opened up? And........who did it?

So far just a phone conversation and a couple of texts. Have not looked at the logs yet. I’m not sure if Poly-fiber was around 50 some years ago? In short not sure what covering process was used,but I’m sure I can get the log entry on both if I ask.
The aircraft is currently being flown and has the starter and alternator installed, so trying to get an idea what they would add to the value, if much to the asking price. I would say asking price falls in the middle of the market.
Engine major was late 80s. Was not indicated if a top O/H or any other work has been completed since. So it was a few years back and not sure how often it is flown, which I realize could be potential for issues.

Concur with Victor and John C above - yes re Polyfiber, I recovered wings in 1968/69 using Ray Stits polyvinyl process (morphed into Polyfiber) - spoke with Ray direct several times over the years. Ray is/was due a lot of credit in "fighting" the system doing all his experimentation to get data to get his system approved - interesting reading back then was the info he published with results - he "paved" the way others. Sure beats tightening the old Grade A fabric with nitrate or butyrate dope. The key to any fabric longevity is proper amount of silver dope to keep the UV rays out - good test is to open bottom inspection plate and shine light of reasonable intensity, holding next to fabric on top and see if light shines through - if seen, approach carefully - can punch test but "gold standard" test is to remove 1" strip, remove dope and pull test against the FAA spec - should be in AC43.13-2A, but I haven't checked lately.

As to procedure, get their book and read it and follow the process as detailed. John Goldenbaum, Stits successor, and Polybiber owner/principal and his crew are ready to answer questions.

As to rejuvenation, that's a term I haven't heard in years! John C is correct, the process was to soften the top dope layers almost to a liquid state to allow the dope to "flow" and give a "new" appearance to the material - didn't do anything to the fabric but possibly give a higher reading on a punch test. In fact, back in the ole days when fabric only lasted a few years with outside storage and marginal process, it wasn't uncommon to see marginal fabric painted with enamel paint to "fool" the punch test. Once saw the old "Mary Carter two for one" latex house paint applied!!

I once saw a 7AC Champ recovered with Grade A cotton and the N number painted on top of the wing in black, parked on tie down, that failed the punch test in three months!! Key to fabric longevity is the doing the job right!!

Key word in Victors' comment - "your" IA! I bought a PA-16 Piper Clipper in about 1960 that was "annualed day of sale" from previous owners in Lafayette LA. In flying home over LA swamps/bayous, I heard a ticking sound, following week found a blown exhaust gasket!! Later found some shim material under prop - bent crankshaft flange!2C

OOPS! In testing fabric with light, should have said " at night or in darken hangar" ! Sorry - senior moment!

Edd

After reading through this thread I question the quality of the fabric on the my airplane.

Researching the subject I found the fabric test in AC43.13-1B. Paragraph 2-34.

They talk about how the test is performed and once you determine the breaking point you refer to Table 2-1 to determine if it passed.

Funny thing about Table 2-1 it only list Cotton and Linen Fabric.

I got lucky and found a chart on the Stewert System website showing New and Minimum strength test numbers for the modern fabrics.

Rick

As far as I know, there is no requirement to ever pull or punch test any of the newer polyester fabrics. As long as the UV blocking coatings remain intact they can last virtually forever.

I was able to obtain a photo of the 337 and it was recovered with ceconite 101. Six coats of brushed nitrate dope,either 3 or 6 coats of sprayed silver as the paperwork is a bit confusing , and 3 coats of sprayed on white enamel.
Now the strange thing currently is the fact the wings are silver, so could it have been recovered since and not documented for some reason or painted?
What is the yearly requirement for fabric testing if any? I know the tests that can be accomplished, just how often.

8395 wrote: ↑Wed Feb 20, 2019 1:07 pmWhat is the yearly requirement for fabric testing if any? I know the tests that can be accomplished, just how often.

6643 wrote: ↑Fri Feb 15, 2019 8:04 pm As far as I know, there is no requirement to ever pull or punch test any of the newer polyester fabrics. As long as the UV blocking coatings remain intact they can last virtually forever.

It is possible you're seeing the silver coat. One of the nice things about using dope is it responds to a different solvent, and you can often remove (or rejuvenate) the top coating without ruining what's underneath.

Originally, planes were delivered from the factory with polished aluminum fuselage and wings through silver.