There are a number of moisture barriers on the market.
Aluminum-based types are NoAlox or Penatrox. We sell a
copper-based product which is part of our model CCK (Copper
Cleaning Kit). A moisture barrier is imperative if you are
dealing with dissimilar metals (e.g. aluminum and copper). While
overkill for your application, exothermic welding (most folks
refer to it as Cadweld; which is a trademark of Erico in
Cleveland, Ohio) is a way of connecting two dissimilar metals
without necessarily needing a moisture barrier.
Sincerely and 73,
Bob Wanderer AA0CY
Senior Applications Engineer
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