Old wing recover and other questions.
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- Posts: 328
- Joined: Tue May 01, 2018 7:00 am
- Location: Florida
- Name: Mike Smith
- Aircraft Type: 140A (2) 1949 & 1950
- Occupation-Interests: Retired aerial power line patrol pilot for Gulf Power Co
120-140 Assoc. Florida Rep. N9633A & N9688A - Contact:
Re: Old wing recover and other questions.
I believe they were bare aluminum fuselages and tail surfaces, not polished. I may be mistaken but I believe I remember hearing that Cessna aircraft did not polish bare aluminum to the mirror surfaces as seen today because it would add too much to the cost of an aircraft out the door (FOB Wichita). They do look nice and shiny in those old BW pictures though.
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- Posts: 11
- Joined: Sun Feb 03, 2019 12:21 am
- Name: Greg
- Aircraft Type:
- Occupation-Interests: Pilot
- Contact:
Re: Old wing recover and other questions.
John,thanks for your reply. I did catch in your previous post about newer fabric pull/punch tests. Is any covering that isn’t linen or Cotten considered “newer”. The last documented recover is 50 yrs old.
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- Posts: 2383
- Joined: Tue May 01, 2018 7:00 am
- Location: KLCI, NH
- Name: John C
- Aircraft Type: 1946 C140/C90
- Occupation-Interests: A&P, semi-retired
- Contact:
Re: Old wing recover and other questions.
Yeah, pretty much so. Ceconite, Polyfiber and Stits all use the same fabric. I think Stewarts does too, but don't quote me on that. There's an outlier, Razorback, which apparently is fiberglass based, but you don't hear much about them these days.
Oratex, referred to in another thread, appears to be a different material altogether.
Oratex, referred to in another thread, appears to be a different material altogether.
John Cooper
www.skyportservices.net
www.skyportservices.net
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- Posts: 11
- Joined: Sun Feb 03, 2019 12:21 am
- Name: Greg
- Aircraft Type:
- Occupation-Interests: Pilot
- Contact:
Re: Old wing recover and other questions.
I found an STC with SA1144WE which appears to be related to covering. I can not find it in the FAA library. Anyone know of it? I was texted a few pages of the logs so I don’t have full access to them. Looks like 1972 era.
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- Posts: 10
- Joined: Wed May 02, 2018 6:35 pm
- Location: I54
- Name: David C
- Aircraft Type: C140
- Occupation-Interests: hobo
- Contact:
Re: Old wing recover and other questions.
I am in the middle of recovering my C140 wings with PolyFiber process, doing the work myself with A&P supervision. Very similar situation to what you are contemplating. I bought the plane knowing the wings were last recovered 40 years ago and would need a recover in the not too distant future. At our first annual we discovered a broken outboard dragwire and I decided to bite the bullet and do the recover now, rather than a repair and patch job.
What I have learned in the process:
1. Expect to replace drag wires - do them all since you're doing it and the wing will likely not be opened again for another 40 years! Unless you are extremely lucky your drag wires will be rusty and the nuts will be rusty. I would plan on replacing all the dragwires - available from Univair (STC'd heavier wires for the two outboard bay pairs). The #12-28 heavy jam nuts used on the 2 inboard dragwires pairs are very difficult to source. I was able to find some usable nuts on ebay and between those and enough of mine that were salvageable I had enough.
2. Expect to make repairs:
- I had a few spots where aluminum flanges were badly corroded under tinnerman clips - those all required repair with riveted patches
- anchor nuts for flap screws and flap stop screws were also badly corroded and needed to be replaced
- several tinnerman plates along the root rib had to be replaced (2 or 3 on each wing). They were broken and "repaired" with a rivnut at some point in time, I elected to drill the mess out and rivet in new tinnermans
- fuel tank filler necks will likely be rusty - I had one that was rusted through. The steel neck is soldered into the aluminum tank - can you say galvanic corrosion?
- fuel tank bottoms will likely having corrosion pitting along the felt strips on the bottom of tank. I have looked at four different C140 gas tanks and all had corrosion pitting along the felt. If bad enough that will required weld repair
3. Expect 40 hours per wing to cover AFTER all cleaning, repairs, and priming - that is just to get to point of spraying
4. It is an enjoyable process, you will thoroughly learn about your wings. PolyFiber is easy and forgiving - just be able to safely work with the solvent fumes.
Cost wise:
~$1000 for drag wires
~$2600 for cover materials
~$80 for all replacement hardware
What I have learned in the process:
1. Expect to replace drag wires - do them all since you're doing it and the wing will likely not be opened again for another 40 years! Unless you are extremely lucky your drag wires will be rusty and the nuts will be rusty. I would plan on replacing all the dragwires - available from Univair (STC'd heavier wires for the two outboard bay pairs). The #12-28 heavy jam nuts used on the 2 inboard dragwires pairs are very difficult to source. I was able to find some usable nuts on ebay and between those and enough of mine that were salvageable I had enough.
2. Expect to make repairs:
- I had a few spots where aluminum flanges were badly corroded under tinnerman clips - those all required repair with riveted patches
- anchor nuts for flap screws and flap stop screws were also badly corroded and needed to be replaced
- several tinnerman plates along the root rib had to be replaced (2 or 3 on each wing). They were broken and "repaired" with a rivnut at some point in time, I elected to drill the mess out and rivet in new tinnermans
- fuel tank filler necks will likely be rusty - I had one that was rusted through. The steel neck is soldered into the aluminum tank - can you say galvanic corrosion?
- fuel tank bottoms will likely having corrosion pitting along the felt strips on the bottom of tank. I have looked at four different C140 gas tanks and all had corrosion pitting along the felt. If bad enough that will required weld repair
3. Expect 40 hours per wing to cover AFTER all cleaning, repairs, and priming - that is just to get to point of spraying
4. It is an enjoyable process, you will thoroughly learn about your wings. PolyFiber is easy and forgiving - just be able to safely work with the solvent fumes.
Cost wise:
~$1000 for drag wires
~$2600 for cover materials
~$80 for all replacement hardware
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- Posts: 10
- Joined: Wed May 02, 2018 6:35 pm
- Location: I54
- Name: David C
- Aircraft Type: C140
- Occupation-Interests: hobo
- Contact:
Re: Old wing recover and other questions.
Forgot to mention fabric clips.
There are roughly 400 and expect that after 50 years many/most of yours will need to be replaced - budget $200-$300 for fabric clips.
There are roughly 400 and expect that after 50 years many/most of yours will need to be replaced - budget $200-$300 for fabric clips.
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- Posts: 11
- Joined: Sun Feb 03, 2019 12:21 am
- Name: Greg
- Aircraft Type:
- Occupation-Interests: Pilot
- Contact:
Re: Old wing recover and other questions.
Thanks David, helps out a bunch on the discussion process and budget.
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