I will resize my photos and try to get them on tonight. After removal of the tank in the right wing I found two rivet heads corroded of on the forward half of the rear spar attach point. Drilled them out last night and the spar attach plates on the wing side of the rear attach point are corroded beyond safety. The forward carry through spar if fine, but the forward plate on the right side "A" pillar door post is corroded pretty badly, where it attached to the forward carry through spar. My plan is to replace every rivet in all four wing attach points and both carry through spars where they attach to the airframe. Also found a manufacturing booboo in the right wing front attach point, I will post a picture of that as well.counsellj wrote:Photos?
Forward carry through spar
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- learaviator
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Re: Forward carry through spar
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"You can only tie the record for flying low"
1950 170A N9907A 180hp. STOL
1950 170A N9907A 180hp. STOL
- counsellj
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Re: Forward carry through spar
Thank you for taking the time and dealing with the hassle to post the photos. I lot of other owners can learn from these.
- learaviator
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Re: Forward carry through spar
Cabin roof skin and front carry through spar removed
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"You can only tie the record for flying low"
1950 170A N9907A 180hp. STOL
1950 170A N9907A 180hp. STOL
- learaviator
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Re: Forward carry through spar
Some more pictures
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"You can only tie the record for flying low"
1950 170A N9907A 180hp. STOL
1950 170A N9907A 180hp. STOL
- n2582d
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Re: Forward carry through spar
Thanks for the photos. Surprising to see that sort of corrosion on an Arizona plane. I'm guessing it was based near the coast in the past.
Gary
- GAHorn
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Re: Forward carry through spar
Corrosion is caused by more than the storage-environment of the home-field.
Airplanes flown in rain, or humid destinations,....wash-jobs... ...leaving the ground, going up to altitude, descending back through temperature-levels for 60 years....with moisture-exhaling occupants... creates condensation...which in partnership with dust/dirt/soaps/time.... all contribute.
Inspect, Inspect, Inspect.
Airplanes flown in rain, or humid destinations,....wash-jobs... ...leaving the ground, going up to altitude, descending back through temperature-levels for 60 years....with moisture-exhaling occupants... creates condensation...which in partnership with dust/dirt/soaps/time.... all contribute.
Inspect, Inspect, Inspect.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

- n2582d
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Re: Forward carry through spar
George, what percentage of time does a plane fly in relation to sitting parked at home base? Answer: Around .8 % of the time for a 4000 hour airframe that is 60 years old.
These corrosion photos are the ones I'll be showing the wife when I try to justify hangar rent.
These corrosion photos are the ones I'll be showing the wife when I try to justify hangar rent.
Last edited by n2582d on Thu Oct 30, 2014 12:29 am, edited 2 times in total.
Gary
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Re: Forward carry through spar
Hangars don't prevent corrosion. In fact, they can speed it up if they don't have good ventilation in them.
They're also attractive homes for mice.
Hangars prolong the time between coats of wax and do a fair job of preventing hail damage tho.
They're also attractive homes for mice.
Hangars prolong the time between coats of wax and do a fair job of preventing hail damage tho.
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Re: Forward carry through spar
Obviously the affordability of a hangar varies based on location which in some areas makes hangaring a tough pill to swallow but I would hangar every time. We haven't mentioned UV damage, but next to corrosion there's another thing that eats away at our investments.
Nothing will stop corrosion, all you can do is try to control the rate.
Unfortunately for the owner based on the pics this aircraft is about to undergo a fairly extensive repair. The pictures shown so far certainly don't suggest its a dry country plane. Might be interesting to see the inside of the wings.
Nothing will stop corrosion, all you can do is try to control the rate.
Unfortunately for the owner based on the pics this aircraft is about to undergo a fairly extensive repair. The pictures shown so far certainly don't suggest its a dry country plane. Might be interesting to see the inside of the wings.
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
1953 C170B S/N 25656
02 K1200RS
- GAHorn
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Re: Forward carry through spar
It's the ...TIME...coupled with contaminates and electrolyte/moisture ...that is the essential ingredient of most corrosion.n2582d wrote:George, what percentage of time does a plane fly in relation to sitting parked at home base? Answer: Around .8 % of the time for a 4000 hour airframe that is 60 years old.
These corrosion photos are the ones I'll be showing the wife when I try to justify hangar rent.
Hangars are good anti-rain, anti-hail, anti-wind, anti-theft, anti-sun... but anti-corrosion? Not necessarily.* A buddy I know installed a drain in the center of his hangar thinking it'd be a good place to wash. He stored his car and his boat in there too. It was heated with a natural-gas furnace (which produced water vapor presumeably because it burned fossil fuel.) The entire interior was a moldy, humid, rusty shell. He was over 100 miles from the coast.
*Keeping it out of the rain, wind (dirt accumulations), and sun slows down corrosion, but it won't guarantee no corrosion.
Wash it using WD-40 as a surfactant instead of soap in the wash-water. It'll lubricate hinges, weatherseals, keep paint rejuvenated, and will penetrate lap-joints to work against corrosion-inviting moisture. Soap is alkaline and will remove lubricants and attract moisture.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

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Re: Forward carry through spar
George, complete your WD-40 recommendation for washing our planes by repeating the ratio of WD-40 / water.
OLE POKEY
170C
Director:
2012-2018
170C
Director:
2012-2018
- GAHorn
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Re: Forward carry through spar
The exact specifications of the recipie is critical!
(A few cups of WD-40 to a 5 gallon bucket filled about 2/3rds under the force of a garden nozzle. I buy WD-40 in gallon cans.)
Rinse the dust off the airplane with a hose, mop it down with the WD-40 solution using a dedicated cotton mop and old towels used only for plane washing, rinse with the hose again, and dry with old cotton towels.
WD-40 in a spray-bottle is also very good with which to wipe the belly down between flights, laying on a creeper and a roll of paper towels. A squirt or two onto the tailwheel spring-set/tailwheel, then scrubbed with a car-wash tire-brush, and a rinse with the hose will keep the tailwheel in show-condition.
WD-40 does not hurt plastic (windshields) or rubber but I don't deliberately apply it there. The little that gets there accidentally just does no harm. I use a good windshield cleaner like Davis, Prist, etc.. and do not use or recommend Pledge (and I absolutely condemn Simple Green in any flavor including their "aircraft" stuff, which anodizes/stains aluminum.)
(A few cups of WD-40 to a 5 gallon bucket filled about 2/3rds under the force of a garden nozzle. I buy WD-40 in gallon cans.)

Rinse the dust off the airplane with a hose, mop it down with the WD-40 solution using a dedicated cotton mop and old towels used only for plane washing, rinse with the hose again, and dry with old cotton towels.
WD-40 in a spray-bottle is also very good with which to wipe the belly down between flights, laying on a creeper and a roll of paper towels. A squirt or two onto the tailwheel spring-set/tailwheel, then scrubbed with a car-wash tire-brush, and a rinse with the hose will keep the tailwheel in show-condition.
WD-40 does not hurt plastic (windshields) or rubber but I don't deliberately apply it there. The little that gets there accidentally just does no harm. I use a good windshield cleaner like Davis, Prist, etc.. and do not use or recommend Pledge (and I absolutely condemn Simple Green in any flavor including their "aircraft" stuff, which anodizes/stains aluminum.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

- Joe Moilanen
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Re: Forward carry through spar
I did a complete corrosion proofing of my entire belly all the way to the tailwheel yesterday. Not an approved method though, and hate to admit the process ( reminder to me: don't answer the cell phone as you just finish adding a quart of oil... glad the oil cap has a chain on it...)
I have been doing a 26 year test of pledge on the windshield though, still looks as good as any that I've seen...
Joe
I have been doing a 26 year test of pledge on the windshield though, still looks as good as any that I've seen...
Joe
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Re: Forward carry through spar
Joe, rest assured you aren't the first nor will you be the last to forget to replace the oil filler cap. It happened to me twice within 6 months several years ago
Sure makes a mess
Fortunately our filler is behind the pressure bulkhead so we don't get the suction that the larger bore Continentals do. I understand they will suck out most of the oil in a fairely short time. The first time I forgot (got distracted) I flew for over 3 hours with the cap off and the tail wheel springs got a good lubercating. As I seem to recall that I only lost less than 1/2 a quart.


OLE POKEY
170C
Director:
2012-2018
170C
Director:
2012-2018
- learaviator
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Re: Forward carry through spar
Bingo!!gahorn wrote:Corrosion is caused by more than the storage-environment of the home-field.
Airplanes flown in rain, or humid destinations,....wash-jobs... ...leaving the ground, going up to altitude, descending back through temperature-levels for 60 years....with moisture-exhaling occupants... creates condensation...which in partnership with dust/dirt/soaps/time.... all contribute.
Inspect, Inspect, Inspect.
"You can only tie the record for flying low"
1950 170A N9907A 180hp. STOL
1950 170A N9907A 180hp. STOL
Cessna® is a registered trademark of Textron Aviation, Inc. The International Cessna® 170 Association is an independent owners/operators association dedicated to C170 aircraft and early O-300-powered C172s. We are not affiliated with Cessna® or Textron Aviation, Inc. in any way.