wrote:
....
I'm working with some galvanized metal ...
... that I'm bending into a box... about 16" x 4". ...
... I want to make sure that it is waterproof as it is
going outside, and want to ensure that it will stand the test of time
in regards to moisture, heat, cold, etc. What is the best way to
ensure this? I've thought that maybe I should purchase a soldering
gun and put some solder on the joins...will this stand the test of
time? How about epoxy or liquid nails? How about using both solder
and some sort of adhesive?
....

http://www.uss.com/corp/sheet/coated/hotfab.htm

How are you planning on mounting the lid (I assume there must be an
access of some sort to get the contents into the box)?

If that has to have access, it'll need a good gasket or if access rarely
needed it could be caulked w/ a good rtv but will be a pita to get into.

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