[VAL] Hoo, boy! RE: 1956 Caravanner Skin Care

["Tom" <tmeeker@xxxxxxxxxxxxxxx>]

Where do you see traces of leaks coming "in" from?  The rivet tail holes?
Dripping down from all or most of the seams?

If you seal your trailer on the outside, really seal it, it will not leak on
the inside.  If you can locate loose or ill fitting rivets (Airstream used
SOLID rivets, not the same as their "repair" rivets which are a blind rivet)
you really need to remove and replace those rivets AND re-install all of
them with a sealer like Vulkem.  The Vulkem should be shot into the rivet
hole BEFORE the rivet so that it forms a tight seal when it is either bucked
(solid rivet) or pulled (blind rivet) with the proper tools.

I would bet you dollar to donuts that the sealer you see coming off is
excess sealer from the day it was manufactured.  This sealer "coming off"
from the trailer seams most likely is due to it being squeezed out from
between the sheets of aluminum skin.  This is NOT unusual - rather is would
be expected but certainly not to excess UNLESS the technicians were sloppy
and applied way too much sealant when it was built.

I'm sure Airstream applied lots of sealer (excess width, not excess
material) to all the trailer seams when it was constructed.  Sealer coming
off skin on the inside which is merely laying on the skin is not a problem -
at all - unsightly maybe but I'm sure there are a lot of unsightly things
behind and underneath all constructed things made by man.

Unless you have leaks from rivet tails (looking from the inside outward on
the interior of the exterior skin) you really do not have a problem.  I'd
love to see pictures of what you are referring to so I can try and help both
of us understand this issue better.

IF you are using a wire brush in your sealant removal this is not in your
trailer's best interest - especially IF you have an older Airsteam with CLAD
aluminum skin.  The aluminum used back then had a CLAD covering of 100%
aluminum on the outside of the alloy sheetmetal.  What is CLAD aluminum for?
To prevent corrosion - *because* it forms an oxide coating on that coating
of 100% aluminum - it sacrifices itself to protect the rest of the aluminum
sheet.  All corrosion is not bad - especially when it's an oxide sacrificial
coating as the CLAD coating is.

Using a metal brush removes the clad coating and you are setting yourself up
for future corrosion that you won't be able to see unless you are doing an
annual inspection by tearing out the inside skin on a regular basis.  You
really want to use a nylon brush or something similar - certainly not metal.

Tom
WBCCI 5303