What do you think of this erosion?

[Chizlam]

Acid rain? road salt? it goes through the clear coat and into the aluminum.

[Safari64]

corrosion ?

[easyride]

If it won`t buff out with Nuvitte #9,or Liquid Gravel,then it time to get out the very fine wet sand paper,the finer you can get that will smooth it out the better. Dave

[Chizlam]

i have done some wet sanding before but it take forever. Any thoughts on the acid bath?

[Brett - TTT]

This is appears to be a classic example of filiform corrosion. It is extremely common on Airstream skins and other coated aluminium alloys most frequently in areas of humid atmosphere. The corrosion starts with defects in the coating which admit moisture and then progresses in presence of aggressive ions such as chloride, sulphate, etc with oxygen and sufficient humidity. ("Sufficient" actually being quite low in this case.) The filament is made up of a leading end and a trailing end. The lead acts as an
electrochemical cell containing a layer of an acidic salt (aluminium chloride) and hydrolysis products. The trailing end is usually a carbonate (aluminium hydroxyde). Essentially you have a miniature battery in action which uses the aluminum as its energy source. An acid bath is NOT the way to cure this ailment and would cause more rapid propigation of the filament and more advanced pitting of the surface.

The best method of removing this problem is to sand it out. Depending on how deep the pitting is you may need to start with 600 or 800 grit and work your way out to 1200 before starting with the appropriate Green Ox, Nuvite, or rouge polishing compound. The final finish needs to be protected with a wax containing product (NuVite is great) especially if the trailer is being returned to a high humidity location or near sources of chlorides such as coastal areas or the salt flats of Utah, Nevada, and California. If a clear coat is to be applied after polishing or texturing care must be taken to avoid materials which will react with the aluminum alloy.

[GREENovaters]

Now that was a chemistry lesson! So you are suggesting that after the clear coat and striping are removed to polish it with NUVITE? I've seen many products out there on the internet and have been wondering if any of them are truly better at polishing with less dust and more shine.

[Melody Ranch]

Jestco Products Buffing Supply (Powered by CubeCart)
Buffing Polishing Supplies Buffing Wheels Compound Polishing Aluminum Polishing Kit - Caswell Inc.

[Brett - TTT]

I am suggesting to use Green Ox which cuts and polishes faster and to finish it with NuVite. This will leave you with the best shine for the time and money invested. Many automotive waxes will tarnish the aluminum during application.

[stefle]

Interesting thread. I just purchased an '03 Airstream and it has slight filoform corrosion around the edges of the aluminum plates just about everywhere there's an edge. The people at Geo. Sutton RV (Eugene OR) do a coating that's like a wax (rub in and rub off) called Xzilon. It's supposed to protect from corrosion (stop the old stuff from spreading and stop new stuff from starting) for 10 to 12 years. Pricey: $1100 for my 22' unit. I didn't want to make the 8 hour trip up to Eugene from San Francisco to have it done at Sutton so got connected with their distributor through them and got the names of some dealers who do the ZXilon
coating near me. One of these dealers, RVs4less in Madera CA, said they no longer use Zxilon, they now use Trident. It's a 2 stage process that causes a negative charge and then a positive charge, maybe like electro-coating. It would cost about the same as Xzilon, but has only a 4 year warrantee. This guy said Xzilon only offers a 2 year warrantee, but I understood from Sutton it would protect for 10 - 12 years, as I said before.
Anyway, has anybody heard about these treatments? Any opinions? I'm trying to decide what to do.
BTW, the fellow I bought my unit from said he sprayed WD-40 on the seams to keep the filoform from spreading.