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Galvanized shackle to stainless steel for saltwater buoy

My question deals with attaching a buoy to a permanet anchor with a stainless steel eye in salt water. The depth of the water is 55 feet at high tide. Can I install galvanized shackle and chain to the stainless steel eye or will that cause electrolysis? If I can not connect galvanized to stainless steel is there a different metal that will hold up?

Fred Abrahamson
Boater - Seabeck, Washington, USA
2005

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2005

I had a different but similar problem - I cast a SS chain in concrete as the anchor for a mooring buoy. The chain ran up to the buoy, was connected by threading the chain through an eye on the buoy and the free and working portions of the chain secured using a SS shackle. Later, I became fearful that SS chain end cast in concrete would not have access to O2 needed to maintain its anti-corrosion property (that's another story) and was trying to investigate it when I noticed the free end of the chain at the buoy end had tremendous pitting and loss of material.

The 'corrosion' was inversely proportional to the distance to the end of the chain and I suspected that end links may have already corrded themselves free and were MIA. The corrosion and loss of metal was a very noticeable effect. I investigated some on the net, and decided the protective 'corroded' surface of the SS chain was being constantly 'renewed' by movement of the chain (investigate the 'another story' above for yourself) and resulting in rapid loss of metal. I decided to try a sacrificial anode , so I put a plain carbon steel shackle on the end of chain and for whatever reasons - the problem seems to have disappeared.

Gary E
- Annapolis, Maryland