On Mon, 19 Jun 2006 18:34:46 +0000, Front Office
wrote:

I need to build a dozen outdoor canopies for an office building.
I want to use structural aluminum channel, bolted with steel bolts.

Where might expect corrosion to arise over the years, and would
it be mainly in the aluminum or in the steel bolts?

Thanks for any help.

Please post here or email me at grayscale[AT]verizon.net

Ralph

a product called Duralac is designed to prevent the electrolytic
corrosion between dissimilar metals.
it is an aviation product made in england. comes in a white and yellow
tube.
it is a toothpaste consistency yellow fluid containing zinc chromate.
it dries slowly to a rubber consistency.

the stuff is used for pop rivets with great benefit in corrosion
control. you just dip them in it prior to setting the pop in a wing
skin.

it is good stuff. two tubes in my aviation tool box.
Stealth Pilot