Thursday, July 27, 2006

Anodes

AnodesMy anodes need replacing.

The picture you see is of Lady Jane's dark underbelly, right at the stern.

The grey lumps in the picture are the sacrificial anodes, which are bolted onto the hull.

The idea is that the rust attacks the anodes, which are of a softer metal than steel, so they corrode away before the steel that is the hull.

Once the anodes themselves are gone, the hull itself starts to disappear.

I have a few anodes which have completely disappeared, so they need replacing pretty quickly to prevent poor old Lady Jane from wasting away completely.

6 comments:

  1. Hi Tim Thanks for your visit to my site and your congratulations, very much appreciated!

    With regard to the anodes, when I was on the thames I used to make my own by getting old car carburettas and melting them down and pouring them into a sand mould! it would appear that the metal was the right sort and they worked well but carbs have change since and not of the right material. Its just a thought but how about buying some footage of the right sort of metal for the sea Zinc? is it (Magnesium for fresh water) and bolting it on to the hull. it strikes me that the ready made ones are "tres expensive" for what they are MG Duff will tell you what the right metal is and lets face it it has only to be "humbler" than the hull and shaft steel to corrode first. I do know that the metal for the sea anodes has just gone up in srcond hand value and thus MG Duff have been able to have a field day. If you know a casting company it would also be really simple to make a wooden pattern for what you require and have them to actually cast them for you Im sure that it would be considerably cheaper than full retail price.

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  2. If they have dissapeared then they are really do1ng their lob properly! I have never known a marine electrician that fully appreciates the benefit of the anodes on a boat. they all pay lip service to them and then wire the kit up incorrectly.
    JMHO that is :o)) A point worth considering. have you checked the "anodic" protection to your engine and generators, now thats an expencive bit of kit that also needs to be looked after, They may have anodes in the cooling system of the main blocks or heat exchangers?

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  3. A good point rob, and one I'll be scratching my head over for a while before actually getting something done about it.

    Regards

    Tim

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  4. I like the idea of melting stuff down - I guess I could use the old plates as a template.

    Just need to find some metal.

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  5. Does it matter that during the period when the tide is out and the hull is resting on the bottom that your anodes are not in contact with the water even though the hull is still in water?

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  6. A good question Litoralis, and one I don't know the answer to - yet.

    Rob, any idea?

    Cheers, Tim

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