[font size="3"][font face="arial"]An interesting and informative article referenced by Roger on the Yahoo LL QS forum. I'll post it here in the Camplite section, but it is equally applicable to QS, TC, TH.
The take away is that stainless steel is the best choice for fasteners in aluminum, but it will still suffer galvanic corrosion, especially in the presence of salt. There is no practical way to insulate the two metals, but the corrosion is limited to the contact area. Roger concludes the damage is confined to the stainless screws, not the aluminum, but I disagree. Further reading indicates the aluminum will always be the anode and will suffer the damage. The good news is the corrosion is limited to the contact area, usually the threads, and will be mild unless covered in salt water. So always use stainless steel rather than steel hardware and wash the camper after exposure to salt spray or road salt.
One exception to the use of stainless steel might be if a clearence hole is drilled completely through the aluminum and a galvanized steel bolt is inserted, thereby preserving the galvanized coating. Corrosion will still exist, but the bolt will be the donor and preserve the aluminum.
Another interesting observation is that stainless steel can and will rust in the presence of water. I notice this on bicycle hardware where a hex cap screw head collects water after a rain. Fortunately screws are replaceable.
[a href="http://aluminumsurface.blogspot.com/2009/04/corrosion-between-anodized-aluminum-and.html"]Aluminum Galvanic Corrosion[/a]
[a href="http://en.wikipedia.org/wiki/Galvanic_corrosion"]Galvanic Corrosion[/a]
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