intergrandular corrosion of wing spar

My A&P has dignosed this condition on my 1964 (Piper)PA28-140. Has
anyone dealt with this? Can the wings be repaired or rebuilt? Is there
a good source for spare wings? I'm in North Carolina.
Thanks,

Chris Hight

N6414W
JQF

It will be far less expensive to purchase a set of used servicable wings,
than to re-build yours. Subscribe to Trade-A-Plane:

http://www.trade-a-plane.com/index.shtml

Karl


"ChrisH" wrote in message
oups.com...
My A&P has dignosed this condition on my 1964 (Piper)PA28-140. Has
anyone dealt with this? Can the wings be repaired or rebuilt? Is there
a good source for spare wings? I'm in North Carolina.
Thanks,

Chris Hight

N6414W
JQF

On 15 Jan 2005 14:24:53 -0800, "ChrisH" wrote:

My A&P has dignosed this condition on my 1964 (Piper)PA28-140. Has
anyone dealt with this? Can the wings be repaired or rebuilt? Is there
a good source for spare wings? I'm in North Carolina.
Thanks,

What does intergrandular corrosion mean? Sounds like a medical
condition.

You should check with Wentworth Aircraft on spare wings. I have also
seen them on eBay.

-Nathan

"Nathan Young" wrote in message
...
On 15 Jan 2005 14:24:53 -0800, "ChrisH" wrote:

My A&P has dignosed this condition on my 1964 (Piper)PA28-140. Has
anyone dealt with this? Can the wings be repaired or rebuilt? Is there
a good source for spare wings? I'm in North Carolina.
Thanks,

What does intergrandular corrosion mean? Sounds like a medical
condition.

You should check with Wentworth Aircraft on spare wings. I have also
seen them on eBay.

-Nathan


It's some pretty bad stuff. But it's 'intergranular.' No 'd' in it if
you want to google and read about it, it means that the corrosion involves
the grain boundaries of the aluminum alloy.

In article ,
" jls" wrote:

"Nathan Young" wrote in message
...
On 15 Jan 2005 14:24:53 -0800, "ChrisH" wrote:

My A&P has dignosed this condition on my 1964 (Piper)PA28-140. Has
anyone dealt with this? Can the wings be repaired or rebuilt? Is there
a good source for spare wings? I'm in North Carolina.
Thanks,

What does intergrandular corrosion mean? Sounds like a medical
condition.

You should check with Wentworth Aircraft on spare wings. I have also
seen them on eBay.

-Nathan


It's some pretty bad stuff. But it's 'intergranular.' No 'd' in it if
you want to google and read about it, it means that the corrosion involves
the grain boundaries of the aluminum alloy.


In worst case, you can crumble the aluminum with your bare fingers. The
most prone alloys are 7075 and (non-clad) 2024, due to their high
magnesium content. Moisture is the big enemy here, as it promouet
surface corrosion, which then attacks the grain structure of the
aluminum alloy.

The only solution is to replace the offending part.

ChrisH wrote:
My A&P has dignosed this condition on my 1964 (Piper)PA28-140. Has
anyone dealt with this? Can the wings be repaired or rebuilt? Is
there
a good source for spare wings? I'm in North Carolina.
Thanks,

Chris Hight

N6414W
JQF

Their has been discussion about this on the Cardinal owner's group.
Apparently intergranular corrosion is actually caused by improper heat
treating of the part, which leaves it vulnerable to the corrosion
causing elements of moisture, etc. As has been pointed out, it is very
bad stuff as you cannot remove the corrosion and treat it if you catch
it early enough, as you can with Galvanic corrosion. The offending
parts must be replaced.

Bruce Cunningham
N30464 C177A

On 16 Jan 2005 12:03:42 -0800, wrote:


ChrisH wrote:
My A&P has dignosed this condition on my 1964 (Piper)PA28-140. Has
anyone dealt with this? Can the wings be repaired or rebuilt? Is
there
a good source for spare wings? I'm in North Carolina.
Thanks,

Chris Hight

N6414W
JQF

Their has been discussion about this on the Cardinal owner's group.
Apparently intergranular corrosion is actually caused by improper heat
treating of the part, which leaves it vulnerable to the corrosion
causing elements of moisture, etc. As has been pointed out, it is very
bad stuff as you cannot remove the corrosion and treat it if you catch
it early enough, as you can with Galvanic corrosion. The offending
parts must be replaced.

Correct, it is in the manufacturing process.

Does stuff like Corrosion X help prevent it?

My A&P has dignosed this condition on my 1964 (Piper)PA28-140. Has
anyone dealt with this? Can the wings be repaired or rebuilt? Is there
a good source for spare wings? I'm in North Carolina.

A good friend of mine went through this exact problem with his 140. It is
not a good deal.

As others have pointed out, it is a non-repairable problem -- the wing spars
cannot be replaced economically. The only fix is to replace the wings, and
that is not cheap.

My friend's experience was a long series of nightmarish problems with
unforeseen consequences (One example: The first set of replacement wings he
found were crushed in shipping, and the shippers refused to pay to replace
them.), and the plane was "down" for well over a year.

You've really only got two choices: Part the plane out, or fix it. If you
want to fix it, call Wentworth, bite the bullet, and pay their ridiculous
price for serviceable wings. Have them ship the wings directly to your A&P,
and get it done as quickly as possible. Having watched this ordeal from
afar, it seems that attempts to find alternate sources for wings will end up
taking far longer, and cost far more, than you expect, and the aggravation
factor is not to be underestimated.

Good luck.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

On 16 Jan 2005 18:07:39 -0800, "Robert M. Gary"
wrote:

Does stuff like Corrosion X help prevent it?

no
because the corrosion is actually occuring between the metallic
components of the alloy deep below the surface.
in 2024 the copper and aluminium can react together.

anticorrosives applied to the surface cant get near it so they are
ineffective.

dont feel too special even boeing airliners have had expensive spar
repairs because of it. piper cherokee flap ribs are quite susceptible
to it.

if you ever take a little tap hammer and tap along a spar web surface
and hear the sound change for no apparent reason you've probably found
intergranular corrosion. (thats how the boeing corrosion was found)

Stealth Pilot