20 years ago, I dissasembled a little super-rusty trailer and took all the pieces to Scott Galvanizing in Ballard. They hot-dipped the whole magilla for about $30. Then I re-assembled the trailer using all SS fasteners. I am still using that trailer for my alum boat and it looks as good now as when it was first done.

The hot-dip zinc places have an acid bath that completely takes care of the rust. they don't like paint, though.
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