[Paddlewise] Aluminum on Kayaks

>  "Peter A. Chopelas says:
>
> Ulli Hoeger asked about skeg materials and I thought I'd add my two cents
> worth to give everyone something to think about:
>
> I would not use aluminum in a skeg and would not have aluminum in the water
> as either a skeg or a rudder on any kayak because there is some evidence it
> attracts sharks.  It is a well know fact that AL in sea water under goes a
> slow chemical reduction called electrolysis, it breaks down the molecules
> on the surface and discharges a weak electric current in the water.  It has
> been suspected by researchers that this current is mistaken by the sensing
> organs on a shark as an injured fish thrashing in the water.
>

I hadn't heard the shark story before; fascinating. But not all alminums
are subject to corrosion in salt water. Alloys containing  manganese,
magnesium, or chromium, or magnesium and silicon, like 6061, are
particularly resistent- it's the copper containing alloys like 2024 that
corrode easily.  Alclad plates,  which have a coating of pure aluminum,
are very resistent to corrosion. Alclad 6061 would be a good choice for
skegs.




***************************************************************************
PaddleWise Paddling Mailing List - All postings copyright the author and not
to be reproduced/forwarded outside PaddleWise without author's permission
Submissions:     PaddleWise_at_PaddleWise.net
Subscriptions:   PaddleWise-request_at_PaddleWise.net
Website:         http://www.paddlewise.net/
***************************************************************************