Storage of Anchor Chain

[cat man do]

I just made a bargain purchase on a pile of 2nd hand 10mm chain (my god this stuff is heavy) and being 2nd hand is showing signs of rust, no flakes, just rusty muck that comes off when wiped.

What I am wondering, as it will be a while before I use it, what is the best storage method to prevent further deterioration.

I was thinking piling it up in a drum and filling the drum with water, cutting off the oxygen supply.

Thoughts?

[osirissail]

Unless you use totally de-oxygenated water, the chain will rust. Submerging it in oil might work.
- - Once the zinc galvanized coating is eaten or worn off the chain it will quickly rust away. This not only eats away at the size of the chain but also makes a considerable mess on deck or in the chain locker as flakes of rust chip or fall off the chain.
- - The only remedy is to take the chain to a company that can strip/clean the chain and then re-galvanize it. Problem is the cost of the process is about equal or more than the cost of buying new chain.
- - Which is why you got that "bargain" price.

[cat man do]

The reason I asked is that there was water in the bottom of the container when I got it, enough to cover 10 metres or so and this looks pristine.
Certainly in much better condition than the chain I had on my previous boat, which, if not sailed for a few weeks also got the rusty look in spots, but after the first drop was all good again

There is still heaps of galv on the chain, but it is scratched, obviously used in reef areas, so like I said, no flake, more just a rust colour that wipes off.

[Delfin]

Originally Posted by cat man do

I just made a bargain purchase on a pile of 2nd hand 10mm chain (my god this stuff is heavy) and being 2nd hand is showing signs of rust, no flakes, just rusty muck that comes off when wiped.

What I am wondering, as it will be a while before I use it, what is the best storage method to prevent further deterioration.

I was thinking piling it up in a drum and filling the drum with water, cutting off the oxygen supply.

Thoughts?

Buy a couple of cans of Fluid Film and spray it on. This is basically lanolin in a can and will preserve the chain for years.

[Steve Pope]

you may find that the "rust" is a stain from the previous chain locker (steel) and that the chain itself is OK. A suggestion I read recently to clean up a length of chain is to take it to a beach and tow it behind a car / 4 wheel drive for a short while, apparently it will clean up very quickly. Also suggested if you needed to get it regalved, as 1/2 the cost of a regalve job is sand blasting it. Tow it, take it in clean, No blasting required! reduce your costs by half.
But to answer your question, you can put it in an airtite container, the oxygen will quickly be used up and there will be no more corrosion until more oxygen can get in.

[captain58sailin]

Maybe you could store it in some fish oil.

[Unicorn Dreams]

Or diesel fuel

[Dockhead]

I would regalvanize it now and sell it if you don't need it. Or store it in clean condition and dry after regalvanizing.

[cat man do]

Originally Posted by Unicorn Dreams

Or diesel fuel

Now we're talkin'

Thanks

Still has me buggered why water wouldnt work, like I said, the stuff that was in the bucket covered was perfect

[cat man do]

Originally Posted by Dockhead

I would regalvanize it now and sell it if you don't need it.

I just bought it because I do need it
and like the tyres on my car, I dont replace them when they still have 80% tread left

[sctpc]

Originally Posted by Unicorn Dreams

Or diesel fuel

.
Or can wd40 stops the rust for years

[tager]

Probably, the chain was just sitting out in the rain, and the stuff that was sitting in the water was not constantly cycling between wet and dry.

[osirissail]

Put the chain out in the sun to dry and then store it in a dry bucket/container away from any water. The idea is to stop any further "rusting" of the chain and submerging it in normal water will cause rusting in those areas where the galvanizing has been compromised.
- - The main wear points of anchor chain is not along the long portion of each link but instead in the inside of the ends of each link where the link and the next link are constantly rubbing against each other. Examine this area carefully to see if there is any apparent reduction in the thickness/size of the chain link. If not, or if not very much then there is considerable life left in the chain.
- - In the modern world the ocean, bays and even inland waterways all contain "acidic water" due to pollution and other run-off. Galvanized chain just does not last very long before the zinc is gone. Welcome to the modern world.
- - However, if the link size is not significantly worn, especially in the ends where each link rubs on the next link then you can decide whether a little rust discoloration and possibly deck staining is objectionable to you or not.
- - Chain is not cheap anymore and I use my chain until the link wear is significant which is usually also means the chain is almost totally rusted. So in the end, it is really a personal decision on how long you can use the chain. Keeping the chain dry and ventilated be it in the anchor locker or stored ashore will minimize any eating away of the zinc and prolong the useful life of the chain.

[Hud3]

Here's how you can remove the rust with a little home electrochemistry setup...

Rust Removal using Electrolysis

Not too complicated, and if you do it in a well-ventilated space you won't blow yourself up.

Next, how to keep the rust off. A favorite trick of live-aboards anchored for months at a time in the same spot is to let out chain every now and then. Dropping the rusty part that's been suspend in the water down into the muddy bottom subjects the rust to anaerobic conditions, which causes the oxidation reaction that created the rust in the first place to be reversed, converting the iron oxides back to iron.

So, if you can find a secure spot somewhere in a backwater creek with gooey black mud on the bottom, that would be a great spot to store your chain.

Or, you could just keep it in a barrel of diesel.

[Dockhead]

Originally Posted by cat man do

I just bought it because I do need it
and like the tyres on my car, I dont replace them when they still have 80% tread left

If you need it, then why store it? Just regalvanize and use.

The reason why I say regalvanize now if because rusty metal will continue to rust whatever you do. Maybe it will slow if you've stored in in oil or diesel, but you will make a hell of a mess, and waste a bunch of expensive hydrocarbons. Once you have eliminated the rust and regalvanized, the chain will be stable and won't deteriorate if you keep it in a reasonably dry place. Especially if it has never touched salt water, it will last for years like that.