Dump those Zincs

[FF]

The latest 136 issue of PBB came and has an interesting article on why Aluminum , not Zinc (or Magnesium in fresh water), should be the choice.

AS we store in FW and do most cruising in the salty stuff this was real interesting.

The source was performancemetals.com and I'm sure they will explain the advantages there.

One big advantage is they are not recycled Chinese junk , yet are no more expensive than a pure US zinc product.

FF

 

[Arctic Traveller]

I read that article, but I have little understanding of why zinc is so prevalent if aluminum is a better material. Still, Steve D's usually pretty accurate in his assessment of these things and Performance metals puts out a pretty good case for aluminum. It's certainly food for thought. Too bad I just bought all new zincs, perhaps next year..........Arctic Traveller

Trawler training at www.arctictraveller.com

 

[rwidman]

I have considered changing because we are docked up a river where it's not a salty as the ocean but I would have to coordinate this with the diving company because they are using zinc anodes.
I suspect all my slip neighbors are using zinc as well.

 

[Chrisjs]

I guess I do not understand how an aluminum anode could possibly protect my aluminum Yanmar saildrive leg?? What sort of anode is normally installed on an aluminum hull boat?
Chris

 

[Phil Fill]

In order for a metal to protect another metal it must have a lower galvanic rating. Magnesium is 1, zinc is 3, Aluminum is 7, Mild steel is 14, SS is 21, Copper/Bronze 27.

The difference between Magnesium and Zinc is not that great, so it better to make sure the zinc is high grade and the zinc is clean of the white oxide coating. Aluminum is used to protect high rated metals when zinc is not practical or going to fast. However its better to find and correct the reason why.

Lastly two metal of large different galvanic rates should not be combine/connected to each other as the less rate will be sacrificed to the higher. In many application aluminum is used as the to protect higher rated metals.

 

[Larry H]

Chrisjs,

The aluminum anodes referenced at Performance Metals Products are not pure aluminum, but contain some other metals and according to their info, will protect the pure aluminum outdrive legs.

 

[Chrisjs]

Larry:
Thanks for the information. These look interesting, though I do not see shapes intended for the Sail Drive and folding prop. I'll give them a call.
Chris

 

[fstbttms]

Larry:
Thanks for the information. These look interesting, though I do not see shapes intended for the Sail Drive and folding prop. I'll give them a call.
Chris

boatzincs.com

Yanmar Saildrive Anodes - Aluminum

Volvo Penta Saildrive Anodes

 

[Chrisjs]

Thanks for the input. I think these must be recent additions to the Boatzincs line.
Chris