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-   -   What about seaside salt air? (https://www.airforums.com/forums/f458/what-about-seaside-salt-air-19735.html)

26.982 amu 12-19-2005 10:13 AM

What about seaside salt air?
 
For those of you who park your Airstreams at the seaside for long periods: does the salt air (that stuff that gives the air the "tang" we all love) pose a problem for the exterior?

RichardT 12-19-2005 10:47 AM

No worries about the exterior (boats are made of aluminum and sit in salt water)
But you should worry about the frame rusting.
Keep the tounge and exposed frame painted and look for signs of problems inside of the belly pan as frames can rust away if not taken care of.

Devoman 12-19-2005 11:39 AM

Salt
 
I live on the beach and have my Airstream out here parked as well.The best solution I have come up with over the years living out here is to wash it down with water at least once a week or every so many days.You tend to have to do with everything such as cars,windows on house,Plants,lawn furniture,etc,etc,I do it to be safer than sorry in the future.salt build always leaves this nasty film on everything that it can touch.

Tinsel Loaf 12-19-2005 08:15 PM

Salt is aggressive on all metals, it brings out the worst in them. A scratch to the aluminum will oxidize and creep under the new coating giving it a powdery edge that gets worse with age. Walberize a lot paying special attention to scratches will reduce the oxidize creep.

jcanavera 12-19-2005 08:33 PM

While I haven't done any beachfront camping with the A/S, I do remember some trips to Myrtle Beach and to St. Augustine. In each case I stayed 7-9 days. I remember a glistening on my trailers which in effect was the salt that was in the air coming off the ocean. My advice is also frequent washing and keeping the trailer Walbernized.

Jack

Boondocker 12-19-2005 08:38 PM

Quote:

Originally Posted by jcanavera
While I haven't done any beachfront camping with the A/S, I do remember some trips to Myrtle Beach and to St. Augustine. In each case I stayed 7-9 days. I remember a glistening on my trailers which in effect was the salt that was in the air coming off the ocean. My advice is also frequent washing and keeping the trailer Walbernized.

Jack

Good thing I am not afraid to look like an idiot :ermm: , so here we go... do I understand correctly that walbernizer is a wash/protectant and not a compounding product? If so is there any merit in using it on my as yet un polished coach? I am still a little confused on this getting buffed process....

wahoonc 12-19-2005 09:07 PM

Quote:

Originally Posted by Gen Disarray
Good thing I am not afraid to look like an idiot :ermm: , so here we go... do I understand correctly that walbernizer is a wash/protectant and not a compounding product? If so is there any merit in using it on my as yet un polished coach? I am still a little confused on this getting buffed process....

I are a charter member of IA (idiots anonymous:lol: ) Walbernize is a protectorant...I have never seen the ingredient list so I have no clue as to what the active ingredients could be ie; carnuba, beeswax, silicone, etc. IMHO I would not want to waste my time or money on applying something that I am going to have to strip off in the near future. FWIW my Clearcoat looks like crap, but other than a very occasional wash that is all it is going to get until I decide to STRIP and then paint, polish or clearcoat.


Aaron:cool:

dwightdi 12-19-2005 11:11 PM

Salt Air vs Airstreams
 
2 Attachment(s)
Airstreams are not ALL aluminum. In fact the salt air can cause a battery effect if there are other metals touching the aluminum. They call it galvanic corrosion. Contact with glavanized metals to aluminum will also cause the galvanized coating to erode much faster and then there is rusting of the underlying steel. The pictures are from an Airstream that spent time on the Maryland sea shore.

26.982 amu 12-20-2005 01:58 PM

Cathodic corrosion protection
 
Quote:

Originally Posted by dwightdi
Airstreams are not ALL aluminum. In fact the salt air can cause a battery effect if there are other metals touching the aluminum. They call it galvanic corrosion. Contact with glavanized metals to aluminum will also cause the galvanized coating to erode much faster and then there is rusting of the underlying steel. The pictures are from an Airstream that spent time on the Maryland sea shore.

When I lived in Florida, I was advised to have my then-new Land Rover rustproofed because of its aluminum body. This involved a cathodic protection system that connected to the battery, and it really worked! Might such a system also work with Airstreams?

26.982 amu 12-22-2005 10:28 AM

Ruststop Cathodic Protection systems
 
I'm looking at this website, which deals with cathodic corrosion protection systems designed for cars. I talked to their sales rep, and it seems like just the ticket for Airstreams! The sacrificial anode is a pure aluminum strip. I would love to get some input from some of you on this before I actually buy the system (about $200) to install on my '69 Int'l Ambassador which will be parked near the ocean.

https://www.ruststopnorthamerica.com/contact-us.htm

26.982 amu 12-25-2005 11:27 AM

Quote:

Originally Posted by Vince Brach
I'm looking at this website, which deals with cathodic corrosion protection systems designed for cars. I talked to their sales rep, and it seems like just the ticket for Airstreams! The sacrificial anode is a pure aluminum strip. I would love to get some input from some of you on this before I actually buy the system (about $200) to install on my '69 Int'l Ambassador which will be parked near the ocean.

https://www.ruststopnorthamerica.com/contact-us.htm

I would be REALLY grateful if someone knowledgeable would give me some input on this! I've been reading about filiform corrosion, especially where salt is a problem, and it seems that a cathodic protection system would be just the ticket--especially if you plan to keep your AS polished!!

ABRACADABRA 12-25-2005 01:20 PM

Not on your Airstream!
 
Vince Brach,

You asked for it ... so hang on!

Cathodic protection is not gong to work with air as the medium. There is not enough continuous continuity for the flow of electrons to follow for protection. One needs an electrically conductive environment (i.e. environments containing enough ions to conduct electricity). Sea air doesn’t get it, undersea does.

Underwater, where the passage of electrons between a nobler and less noble metal occurs, the sacrifice of a material (galvanic anode – surface to protect is made the cathode)) is applicable. In this environment, the sacrificial material requires continuity with the metal intended to protect.

Even under water, isolation of the material to be protected, such as paint (e.g. your Airstream plasti-coat) is the primary defense of the skin material deteriorating. Coatings have been developed as a need to protect equipment from environmental damage. When the coating fails, or is scarred to expose the aluminum, corrosion sets in. (OXIDATION)
Aluminum, vastly different that ferrous materials, is a self-protecting material. It will corrode or oxidize enough to stop the exposure of oxygen and stop. You wash it off and do not re-coat it; it will corrode itself again, but only to the point of protecting itself from oxygen exposure. Some material will be lost in this process.

Unprotected steel forms a layer of iron oxide, which is permeable to air and water and allows corrosion to continue underneath. Therefor the POR 15 applications to frames, so prevelant within this Forum.

Galvanized steel (zinc-coated) is an interesting combination of materials. Zinc oxide (produced on the surface of zinc-protected objects) is impermeable, as long as the zinc and zinc oxide layers are undisturbed (i.e. not scraped or sanded off), the steel underneath will not rust. [This is the cool part] Galvanised steel has some self repairing properties; small scratches where the steel becomes exposed will be re-covered by the zinc. The zinc from the surrounding area will dissolve and be deposited on the steel, replacing what was lost to the scratch.

There is another steel, Cor-Ten steel. Somewhat different it the fact that it is slightly self protecting, although requires a total different dissertation. You see it used often in bridge construction. Not related to this discussion.

Now the (GALVANIC) inter-action of adjacent or connected dissimilar materials is somewhat of a different story. (e.g. clearance lights, etc.). There you have the passage again of electrons between the nobler and less noble metals occurring, and the less noble will deteriorate. Here, an isolation (dielectric) material should be used to avoid the direct contact of the two dissimilar materials. Isolation is the only solution to avoid corrosion in these types of fittings.

There is such a thing as impressed current cathodic protection, but here again you require the medium to allow continuous continuity for the flow of electrons. This system can be applied if the metal to be protected is coupled to the negative pole of a direct current (DC) source, while the positive pole is coupled to an auxiliary anode.

SUMMATION In an airborne environment, your best protection is an adequate coating. Minute areas where the coating may not have penetrated or has been slightly scarred, can be washed frequently and avoid any loss (deterioration/corrosion) of the material. Only re-coating the section or spot coating will stop corrosion. (need to eliminate the exposure to oxygen)

Now Ya’ll may want to pick this apart, or attempt to get technical, and that is your prerogative...

BUT THAT’S MY STORY & I’M STICKEN’ TO IT! It’s all chemical Magic!

Creampuff 12-25-2005 01:46 PM

I live over a mountain range 5 miles from the coast in CA. and can tell you that polishing without some kind of clearcoat protection is only going to lead to disappointment after as little as 6 months,
I have polished 2 trailers and seen the first go very bad due to proximity to salt air. I have experimented with a spray on clearcoat with modest success and am watching side by side test panels oxidize over a few months. The jury is still out as to whether this is the magic solution to the problem, primarily because it does take some of the high polishsd look down somewhat- but it does definitely seem to solve the oxidqtion issue. I plan on posting more on this as the tests become more conclusive.
Bottom line - IMHO, resist the temptation to polish until you can get away from the ocean.
I just bought a '58 Flying Cloud which I'm DYING to polish- but I'm NOT GOING THERE
(yet!!!)

dwightdi 12-25-2005 05:25 PM

Galvanic corrosion
 
Galvanized (zinc coated) steel in contact with unclearcoated aluminum in sea coast or salted road enviroments.

Zinc is higher than aluminum on the galvanic series and therefore corrodes and generates a battery, protecting the aluminum. That unfortunately, also means the zinc will rapidly deteriorate to protect the aluminum. The usual life expectancy of zinc coated fasteners will be greatly reduced. After the zinc is gone, the base steel will then immediately start to rust but because steel (iron) is lower on the galvanic table than aluminum the aluminum will also start to deteriorate to protect the iron. Pure aluminum (like on the surface of Alcad sheet) will form a protective oxide coating to help stop the corrosion of the aluminum and stop the protective effect of the aluminium.

Early WWII airplanes were made from an aluminum alloy called 2024 which contains a small amount of copper (so the material can be heat treated to give higher strength). Unfortunately, the planes in the Pacific and on carriers corroded badly because the alloy did not form a good protective barrier. As a result, they invented Alclad ( which is a sandwich of pure aluminum on the two outsides skins and a heat treatable 2024 core). This solved the problem. You can still buy the stuff.

Our trailers are not made with Alclad. The alloy Airstream uses had better corrosion resistance than 2024 but not as good as pure aluminum (which is pretty soft and has poor yeild strength properties). There are also some aluminum castings on some of the trailers. The alloy they use for these parts has poorer corrosion resistance than the sheet materials.

If you are going to use zinc coated steel fasteners or accesories (on the trailer in a salt seacoast enviroment) you should keep an eye on them and replace them as soon as they start showing rust. Another alternative is to use a plastic washer or gasket to prevent steel touching the aluminum. (I put HDPE washers under the bolts holding the belly skin on.) The zinc coating on the self tapping screws gets eaten by the salt or worn away quickly by the movement between the skin and the frame. The skin then corrodes leaving a big hole and no support.

If you have to use other than aluminum fasteners on the trailer, use stainless steel fasteners (insulating them should also be considered) wherever you can.

dwightdi 12-25-2005 05:43 PM

Galvanic corrosion
 
Special precautions should be used when disimilar metals are used in a sea coast or salted road enviroment.

Pure aluminum forms as good protective coating (as stated in the above posting) Unfortunately, our trailers are not made of pure aluminum. Pure aluminum is fairly soft and has poor yield strength. The early airplanes were made from a heat treated alloy called 2024 for strength. Unfortunately, the copper contained made it form poor (non-protective) coating and the planes corroded badly. That is why they invented Alclad. Alclad is two sheets of pure aluminum sandwiching a core of heat treatable alloy. Our trailers are not made from Alclad, but the alloy Airstream uses has better corrosion resistance than 2024.

Zinc is higher on the galvanic scale than aluminum or steel and will protect them from corrosion by sacaficing itself. The zinc gets destroyed in the process. That is why galvanized fasteners have a shorter than normal useful life when in contact with the skin of the aluminum trailers. Keep an eye on them and replace them at the first signs of rust because when the steel is exposed and the aluminum trailer will start to corrode to protect the fasteners. Put a plastic gasket or washer between any disimialar metals when ever you can. Use stainless steel fasteners (with insulation) where ever you can on the trailer.

26.982 amu 12-25-2005 06:01 PM

[quote=ABRACADABRA]Vince Brach,

. . . There is such a thing as impressed current cathodic protection, but here again you require the medium to allow continuous continuity for the flow of electrons. This system can be applied if the metal to be protected is coupled to the negative pole of a direct current (DC) source, while the positive pole is coupled to an auxiliary anode. . . .

This is exactly what the people at the rustproofing site are offering. Given that mornings on the coast are often dripping wet and salt is everywhere, I think that impressed current cathodic protection should work--especially if a sacrificial anode of zinc is used. The sales rep mentioned that a current of only 38 mA at 12V is all it takes. He also said that you can SEE the effectiveness as the sacrificial anode corrodes!

What I am surprised about is that almost no one on this Airstream site seems to have experience with having tried this form of corrosion protection. I'll say this--it worked great on the aluminum-body Land Rover I had in Miami for six years!

ABRACADABRA 12-26-2005 04:29 PM

I don't thnk so!
 
Vincie Baby,

Your impressed current cathodic protection needs an electrolyte to work. You do not have enough ion concentration in your ‘wet air’ to conduct electricity.

Your sacrificial anode of zinc will deteriorate (corrode) by itself, without the impressed current. You do not even have to pay $$ in order for that to happen.

I guess my aluminum bodied 1987 Aston Martin Volante, always kept on Palm Beach Island, was protected by the impressed current of ZZ TOP being blasted through the material ... thus keeping the body panels in constant vibration and shaking off any corrosion. :alien:

yochanan 01-21-2006 11:56 PM

Thanks for all of the fantastic input. I bought a Tradewind that I have parked, undercover, across the street from the beach in Oregon. I needed all of this information and more. Much of the clearcoat is gone from the top and I understand that the Walbernize will be of little use on the metal in the absence of the clearcoat. That being the case, are there any waxes I can use to keep that bare aluminum protected??

Regarding the frame, I was considering as a stopgap measure, keeping it coated with a nice film of LPS-3.

John

dwightdi 01-22-2006 07:55 AM

Coating systems
 
When I was the materials engineer for Johnson/Evinrude (OMC) I tested LPS-3 at our Florida salt spray rack for resistance to enviroment and corrosion protection. It turned out to be one of the best products on the market for protecting steel and zinc plated steel. Gave a fairly heavy fairly hard coating that did not wash off easily.

Also tested alot of waxes. All the competitors were about the same at that time, but that was along time ago. You might check consumers report for car waxes.

Tested many galvanic protection systems for imersion applications but never on the salt spray rack. For imersion, both sacrificial anode and electronic systems worked well.

razorback 01-30-2006 12:39 AM

Can the Walbernize be used on a new AS? I looked at their website and it stated:

WALBERNIZE glaze finish is long lasting and detergent resistant. It can be used on chrome and glass.
Not recommended for clear coat finishes.

Doesn't a new AS have a clear coat of some type on the metal? Do owners use this product on the newer AS?


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