What Type of Aluminum for Seam Flashing?

Let me start by saying this forum has been a great help. You all are awesome and filled with knowledge that knows no bounds. (Have I buttered you all up enough )

I don't have an Airstream, but I do have a very old (1940's) AS knock-off that I am repairing. I have another thread (http://www.rvforum.net/SMF_forum/index.php?topic=87437.new;topicseen#new)where I received great suggestions on how to seal the lap joint between the 2 seams.

After really inspecting the current rivet holes and the wooden ribbing within the trailer, I've realized that I can't just rivet them together. For one there is too much damage (holes elongated, gashes between holes, etc. Secondly, the wooden ribbing is supposed to attach to the roof. Apparently, when the unit was first built, the ribbing was installed and the skin laid over it.

What I have decided to do is fill the seam with Vulkem 116 and then use stainless steel aluminum flat head screws to close the seam by attaching it to the interior wood ribbing. My plan is to then cover the entire exterior seam with a 6 to 8 inch wide strip of aluminum. This would be sealed with Vulkem and riveted along the edges. This would cover all of the screw holes, gouges, etc. The only thing someone would see is a riveted band from one side to the other.

I hope I described what I need to do. The question I have is:

What type of aluminum should I use for this band? It needs to be flexible enough to conform to the bend in the trailer but sturdy enough that it won't rip. While the trailer currently is painted, my wife wants it to be bare aluminum. I have no idea what type of aluminum is under the paint nor if it can even be polished like an AS.

While I only showed the front of the trailer, I have the same repair on the rear.

The original aluminum is probably .040 thick. A strip of .040 would be flexible enough to make the radius and stiff enough to stay pretty flat over the  uneven areas. It also will not dimple as quick as thinner aluminum. .040, .032 and .024 are common thicknesses. I would check out the different thicknesses and see what feels comfortable to work with. What ever you use I would pre-shape it, start at the top center and work toward the edges. Fastening in the same order. You might want to consider leaving the band long and pulling the band down tight on each side after you have started several fasteners along the top center. I would do a dry run first before starting with the caulk.

Hope this helps, Tom

tc tom said:

The original aluminum is probably .040 thick. A strip of .040 would be flexible enough to make the radius and stiff enough to stay pretty flat over the  uneven areas. It also will not dimple as quick as thinner aluminum. .040, .032 and .024 are common thicknesses. I would check out the different thicknesses and see what feels comfortable to work with. What ever you use I would pre-shape it, start at the top center and work toward the edges. Fastening in the same order. You might want to consider leaving the band long and pulling the band down tight on each side after you have started several fasteners along the top center. I would do a dry run first before starting with the caulk.

Hope this helps, Tom

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Thanks Tom - Any suggestions on where I can get the aluminum from?

You might try a machine shop. I don't know if you have a Alro Steel distributor where your at but they sell damaged and cut offs a lot cheaper. Check to see if there are any other steel distributors in your area. You might also check a roofing supply.  There is also a company called Town and Country Industrial Metals. If all that fails you can probably get it on line and shipping would not be much because of the small quantity.

Tom