On Tue, 30 Aug 2011 18:58:53 +0700, Bruce
wrote:

By the by, I've used 5200 when mounting stainless hardware on aluminum
when I didn't have anything else. several years later I had occasion
to take the fittings off to repaint the spars and the screws came out
with a common screwdriver and there was no signs of corrosion
anywhere.

====

Yes, it's good for preventing fastener corrosion but Skip's
application is different. Essentially he is trying to seal up an
external seam between the toe rail and the deck as I understand it.
That is a somewhat problematic application because it depends on
adhesion to exposed surfaces for effectiveness, and it gets full
exposure to sunlight. We've had good luck with the 3M 4000UV on our
front widshields which have a similar issue. Nothing is truly
permanent in that application but we've been getting 2 or 3 years on
average.