Chain Rust Prevention (but then easily removed)

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Dave100456

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I'm end for ending my 100m chain as the first 30m has lost its galvanising.

In a year or so I'll get the whole chain regalvanised.

Any suggestions to stop the 30m in the locker from rusting anymore? However, I want to avoid paint it as, prior to regalvanising, it will require removal which will be a pain.

So is there a "preserver" thats easily applied yet easily removed?

I did think about storing/coating in veg oil as it can be washed off with minimum environmental impact.


Thanks
 
Aside of any coating (I'd use Wayoyl too BTW) the biggest favour you can do the whole chain, not just the rusty bit, is to rinse it with fresh water after every use. Leaving it pickling in dried seawater in the chain locker for weeks is asking for corrosion. Treat seawater like you would battery acid - to be avoided on metal wherever possible and minimised when it's unavoidable.
 
LadyInBed said:
I thought that part of the prep before the hot dip was to degrease and clean the chain.
If you don't want to paint, how about Waxol or similar name product. Used on the underside of cars and in trailer box sections.
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My thoughts too. Speak to the galvaniser, the one I used was more bothered by grease and dirt than he was by paint.
 
Dave100456 said:
Thanks, Spoke with a galvanising company who said the opposite of the one you used.
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Paint and weld lag will prevent the galvanising sticking to the steel. In fact if these was any part that I did not want the zinc I would paint it like and threaded parts of stainless steel.

Grease or oil would be removed in the pre galvanising wash/ acid baths
 
Had a look on internet for amateur test of home preventions and there didn't seem to be much difference between expensive and cheap coatings.

Yes, I agree that some form of oil is prob the best way fwd. I can make a cover for the chain thats going to reside in the locker so that it doesn't get wetted by the used retrieved chain dropping on top of it. However, if extra scope is needed the ungalvanised chain can be deployed as a last resort.

What oil do you think would be best? heavy engine oil, veg oil or something else?
 
I'd use ACF50, used it for years on motorbikes through winters as a rust preventer, I coat boat engines with it. Buy the litre bottle with refillable spray bottle rather than the spray cans, about £25 and it'll last you forever. Washes off easily with warmsoapy water or dunking the lot in the sea. FWIW it's also about the best penetrant I've come across...
 
When I took chain that had some paint marks and loose rust to BE Wedge for re-galvanising, they burnt it off beforehand. The procedure is to pass the chain through the galvanising bath without the prior cleaning, pickling and flux baths. The clean chain then goes through the full process. Something like 50% is added to the cost.
 
Thanks Vyv. I knew the cost increased if the chain was not "process ready" but didn't think it would be as much as +50%. With extras added on the regalvanising route becomes less financially attractive.

At present, I'm sailing in very shallow area (Bahamas and Raggeds) that requires only around 50m chain capacity. I could just cut off the rusty bit but its a shame to break up a 100m length.

Have to say the 8mm G70 Maggi has not been the best in terms of galvanising as is well documented on forums.

There are lots of galvanising plants near to Virginia where I'm currently on the hard and some have spin capacity, haven't contacted them to make sure they are familiar with G70. If I come back to Europe next year Ill contact BE Wedge.
 
There is a lot of rubbish published on forum on regalvanising G70. Mostly by people who know little about galvanising, less about Maggi's G70 and will certainly never have re-galvanised Maggi's G70 nor tested before and after.

I suspect that Maggi's G70 was based on a G100 feedstock, or something similar. When it is originally manufactured, as G100, the alloy for the steel is carefully selected and the product is quench and tempered. The result is a chain of G100 specification. Maggi then take this product, around a G100 quality, and then galvanise it - they effectively retemper it. If you re-galvanise the chain you will subject it to the same heat process, or as similar as makes no difference, as Maggi did and the product after the second galvanising will be the same strength, or the difference will be negligable, You can confidently regalvanise Maggi's chain and expect the same strength before and after.

Most industrial hot dipped galvanisers work to exactly the same temperature baths, the same soak times - Maggi's process will be within world wide practices.

I took some of Magghi's G70 and subjected it to galvanising here (in Sydney), the strengths before and after were similar. Independently Peerless told me the same thing.

I don't know if Maggi shot blast or pickle (acid wash). Pickling has caused Hydrogen Embrittlement.

If you shot blast you need to do so and get the chain to the galvaniser the same day and galvanise the same day - corrosion stops for no man and if its not spotless - the gal will not take. You need to get all your ducks in a row :( You could enquire - think shot blasting, drop into diesel and maybe this will give you time to get the timing wrong. I don't know how a galvaniser will react to a diesel soaked chain. One problem of chain - it needs men to load it for the gal bath - the galvaniser might be less enthusiastic if it is soaked in diesel.

The enthusiasm for US galvanisers to re-galvanise chain appears to be waning - check - it might be more difficult than you think to have it done.

One way to clean up chain - drag it behind a vehicle on a beach.

I'd try to clean up the 30m of rusty chain, maybe drag is along a beach! Then try whatever treatment you think best for the now clean portion and store it separately from the 70m you are using (hang it from the sides of the chain locker ABOVE the daily use chain (so you can keep it accessible should you need to deploy more than 70m). Wash it regularly with fresh water - and air it when ever possible.

Just out of interest - how long has it lasted?

Jonathan

Regalvanizing G70 Chain - Practical Sailor

Regalvanization of anchor chain - Cruisers & Sailing Forums
 
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Hi Jonathan
Thanks for the useful info.

I have a deep anchor locker at the foot of the mast and can bag up the rusty chain in preservative to isolate it from the length in use. Should I need all 100m it can be deployed from its storage.

I'll measure the rusty links to ascertain material loss. Am I correct in thinking that a maximum of 10% loss in diameter is the point at which the chain should be scrapped?

The Maggi was new in April 18 shipped from Italy to the boat in France. The galvanising didn't look very thick when new. I specced the 8mm rather than the std 10mm G40 chain the shipyard usually uses.

In the last 24 months we have anchored most days but still I'd have expected the galvanising to last more than 2 years.
 
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Dave100456 said:
Have to say the 8mm G70 Maggi has not been the best in terms of galvanising as is well documented on forums.
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Before re-galvanising, scrape some of the rust away and check the thickness with callipers.

It does not take much material loss to make the reduction of strength unacceptable for thinner G70 chains. A 10% loss in diameter (this is about a 19% loss of strength) is often quoted as a maximum. So you are checking for less than a 0.8mm loss for your 8mm chain, although you may choose to be more conservative than these general recommendations depending on your requirements.
 
noelex said:
Unfortunately, we had a similar experience.
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Because of the reports on the web of people having similar experiences and my distance at the time from Italy or the country where I bought the chain, I did not take this up with Maggi.

I like the weight saving of 8mm and wonder if there are US 5/16" equivalents which I could explore although they would need a new gypsy.
 
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