Originally Posted by 66deuce
What about using aluminum? It doesn't conduct electricity, is lightweight, won't rust, and can be found at Home Depot or Lowes.
In fact aluminium ''rusts'' almost instanttaneously. In contact with oxygen, air or water, it forms an oxide layer that has excatly the same dimensions as the base metal, forms solid crystaline structures and adheres well to the base metal. It also protects the aluminium from further corrosion so the reaction stops once a certain thickness forms.
The rust of ferrous alloys on the other hand are larger the the base iron metal and have a brittle crystal latice. So as soon as it forms, it expands and breaks off, leaving more underlying metal to be corroded. So once ferrous alloys start rusting, it's just a matter of time.
Under the right conditions, aluminium can rust, it's called white rust, and when it does, it can rust very, very quickly.
Since salt water dissolves the aluminium oxide layer, it will in fact rust under salt water and is therefore not a good idea.
Neither is brass as it contains copper that will leach out significantly.
As for stainless, 316 should be good, but not always. Stainless steels must be passivated once they've been machined otherwise they don't retain as much of their stainless properties. I doubt very much that over the counter stainless hardware is passivated. Especially since it involves near boiling nitric acid with a chromic acid inhibitor, nasty stuff.