Re-Galvanizing

[model 10]

I am thinking of sending the chain in for a re-coat. It is priced by the pound and the more the better price so I am also thinking of getting the anchor done at the same time. My concern is, do you loose the old coating on the surface or does it just add on to the old surface? More would be better but a new coating might be pretty thin and the Rocna looks pretty good still. I would hate to loose the coating that is still there.

[bstreep]

My opinion is this: If you want to get the anchor re-done, by all means.

As for chain... You will not be happy. The zinc gets caught up in your gypsy, it also makes a mess on your deck. They don't get it all, and some links get stuck together. My advice is save the money, and apply it towards some new chain. Wish we had.

[wsmurdoch]

Galvanizing Process | AZZ

The acid bath should strip the surface zinc.

AZZ in Bristol, VA has done my chains twice and anchors once with no problems. I've had no stuck links and no flaking of the zinc coating.

[biker6977]

If you find the right supplier you shouldn't have a problem. They will have to clean them and quite possibly strip them. You can ask what the finished coating thickness will be. The links should not stick together and if done properly won't. In my automotive life I've worked with a lot of coating suppliers and the best is not the cheapest.

[sy_gilana]

We have re galvanized our anchors and chain twice. Once in Cape Town and once in Venezuela. Both times a great success.
Generally the hot dipped re-galvanizing s better than the original thin coat.
It also adds several kilos of weight.
Acid bath is the first part of the process so no, none of the original will be left, its naked etched steel that goes in the bath.
If a ''dirty'' item gets dumped in the 600 deg C molten zinc bath there will be an explosion.

[Night_Sailor]

Cheaper to buy new chain than to re-galvanize.

Properly done it is not a coating so much as a tradition between steel and increasing amounts of zinc.

Hot dipping ? I think that is just a coating not a metallurgical blending with the outlet layers of steel.

I'll ask my girlfriend about it. She is a PHD materials guru.


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[sestina]

It's a matter of finding a galvanizer who has got the right equipment for handling chain, otherwise it will end up as a congealed lump.

Here in the UK, B E Wedge, in Willenhall re-galvanized 60m of 8mm chain, plus my 35lb CQR for £170. Took under a week. Considerably cheaper than replacing my UK made chain with Chinese rubbish.

All items for galvanizing are acid dipped to clean them back to bare steel.

[JPA Cate]

FWIW, we've re-galvinized for years. No complaints.

Heard one time, where it is not shaken, people received their chain rode back on a pallet, all secured in a lump that had once been molten zinc. They broke it up with sledges, and somehow, after a while, the galvo had crept around and sealed the voids.... Amazing chemistry.

Ann

[OceanSeaSpray]

Originally Posted by Ann T. Cate

FWIW, we've re-galvinized for years. No complaints.

Heard one time, where it is not shaken, people received their chain rode back on a pallet, all secured in a lump that had once been molten zinc. They broke it up with sledges, and somehow, after a while, the galvo had crept around and sealed the voids.... Amazing chemistry.

Ann

Same. I re-galvanize, it seems such a waste to toss out a perfectly good chain... Best job I ever got was in Durban, South Africa. It came back with many frozen links, which I had to break up, but no big deal.

Ideally chain needs to be spun when coming out of the bath, but few places are geared for that. Shaking it does a reasonable job. A good re-galvanising job often leaves more zinc on the chain that it originally had in my experience.
G30 / G40 grade chains, standard for anchor chains, take the heat quite well and can be redone many times. The few misguided ones that have opted for smaller chains of higher tensile strength got it wrong there too, because the reheating can lead to embrittlement etc. Those are throw-away.

Eric

[wsmurdoch]

I was charged $105 in November of 2012 to regalvanize 246lb of chain and anchors. I had no frozen links in the 5/16" BBB chain, and I was quite happy with the work. One of the anchors was a Simpson Lawrence Delta with a lead filled tip. It was suspended tip down in the zinc bath to keep the lead from spilling and I lost less than an ounce of lead from the fill hole. Regalvanizing was much less expensive than replacing.