Thoughts on Stainless Steel Anchor Chain?

[conchaway]

The MAIN thing is make the the last foot or so that attaches to the boat should be LINE, NOT CHAIN! When your anchor is jammed on the bottom, you'll never get a rusted metal attachment loose! ( Yes, stainless WILL rust under the right conditions). Been there.

[Departing2017]

Originally Posted by Alan Mighty

Excellent choice, D2017.

I tried to design my questionnaire so that those choosing (a) at each question were suitable customers for stainless steel anchor chain. While those who chose (b) were better staying with galvanized steel.

The boat in the next marina berth to me is a good example. He (let's call him R) has a 30-something foot runabout, called a 'bowrunner'. It's a sort of party boat thing. Rumoured to sometimes have skimpily-clad people on board (an unfounded rumour, Mrs R).

R drives out of the marina, anchors in coastal aerated water over clean quartz sand. Has a cold beer, chars some mammal flesh on the BBQ, then runs back to the marina.

The anchor and chain come up clean. Look superb - genuine boat jewelry. Chain stows neatly in the locker.

R uses 316 austenitic stainless steel chain, an austenitic stainless steel shackle, and an austenitic stainless steel anchor. Washes it down with dock water back at the marina.

The clean quartz sand presents little galvanic risk to the stainless steel. The short dunking, followed by a freshwater wash, minimises a lot of the corrosion risk. The anchoring and the stowage present little risk of low oxygen levels.

Cruisers know that 316 austenitic ss is a compromise and a compromised material.

For a cruiser, the duplex stainless steel chains and shackles (2205 or 318LN) are much less of a compromise. Jolly expensive (~US$15 a foot for 8 mm 5/16" short link) to buy. And only worth buying if tested and certified. And then either inspected. tested, and re-certified or replaced.

As Simi 60 and others have mentioned, Cromox Suprene 40 at Euro 60/metre for 8 mm 5/16" short link, made of 2507 super-duplex stainless steel is the one to get.

I've followed Jim Cate and others in replacing 316 austenitic chainplates and chainplate bolts with 2205 duplex and/or 2507 super-duplex ss.

Galvanized steel ground tackle, likely to bend or stretch before it breaks, remains my choice, even though I have embraced duplex and super-duplex to anchor the rig to the hull.

Jim Cate has proven duplex ss chainplates for 25+ years of service. No one has yet proven super-duplex anchor chains for that duration.

You'll like my other thread. Replacing chainplates with titanium, including titanium bolts. Now that's boat jewelry. https://www.cruisersforum.com/forums...ms-238462.html

[skipmac]

Originally Posted by conchaway

The MAIN thing is make the the last foot or so that attaches to the boat should be LINE, NOT CHAIN! When your anchor is jammed on the bottom, you'll never get a rusted metal attachment loose! ( Yes, stainless WILL rust under the right conditions). Been there.

Yes. Could be a boat saver.

AND to go along with this advice, always make sure your anchor is ready for immediate deployment anytime you are close to shore, reefs, etc.

[Nani Kai]

Originally Posted by HopCar

.......I’ve seen various pyramid shaped things put into the chain locker to keep the chain from piling up. As the incoming chain hits the top of the pyramid it is forced to fall to one of the sides preventing it from piling up in the center of the locker........

This seems to me to be the best suggestion. I modified our anchor locker by installing a wall just forward of where the spurling pipe drops chain through the deck. I also tilted the bottom of the box aft so that the chain is distributed away from the pipe. There is not enough space forward of the spurling pipe to allow chain to stack up so the pile has no where to go except where I want it to.

Works great.

[Nani Kai]

Originally Posted by joelhemington

I'm curious, having lived on Oahu for twenty years and sailed around the whole island at least a couple of times, where exactly do you anchor? Waikiki has a pretty good sand bottom but it's about a 60' drop (so lots of scope needed) Every where else is pretty much surrounded by reef and drops off radically deep once you get out far enough to avoid washing up on the reef. Sunset Beach in the summer is very calm but the bottom there is all rock as the winter swell tosses all the sand back up on the beach. Hanalei Bay on Kauai is the only place I recall seeing people anchor and that could be a three day sail from Oahu.

Manalua Bay near Hawaii Kai has anchorage just off the channel to the south for shallow draft vessels. Depending on your ground tackle and the swell you can also anchor on the north side of that channel in about 30'-40' depth; mind the swell here if it has any south component. Waikiki: just offshore you can anchor in 30-40' of water, if you know the area well, in between the finger reefs running perpendicular to the beach south of the Ala Wai Marina just outside the surf break known as "Kaisers". Off Ala Moana beach park, north of Magic Island you can anchor in 30' most of the year except when a south swell is running. A couple of spots here until you approach Kewalo Basin channel. Keehi Lagoon of course has anchorage, or at least there was still space available when I was last there in 1996. Could be all mooring balls now or so crowded you might not want to anchor there. Safe anchorage on the west side as you continue north from Keehi is pretty iffy. I know some areas you might investigate just north of Campbell Industrial Park barge harbor entrance. North of Kahe point is a possibility. There are a couple of spots just outside the breakwater at Waianae Harbor. I've anchored big dive boats near an airplane wreck there. 25-35' of water if memory serves. You know what, PM me and let's talk. I don't know the North Shore quite as well and pretty much nothing about the NNE shore until you get to Kaneohe Bay, the Mokoluas, then eastward to Rabbit Island, Makai pier, etc. I realized a little late that this post is pretty meaningless to other CFers not living on Oahu. Aloha, Nani Kai

[Alan Mighty]

Originally Posted by Alan Mighty

DSS was invented a couple three times, just but increasing the proportion of chromium in the melt. At least once it was by accident. That was in about '35, when a factory was making a standard austenite ss by the formula and blundered because one bloke tipped too much chromium into the melt. That resulted in a demerit for the worker who'd 'wasted' the precious chromium powder, but the foundry got a patent for the result! I don't remember if the first foundry making dss (Avesta of Sweden making 453 dss) held a patent for dss (I've always found Swedish patents difficult to research - feel free to interrupt if you're good at Sverige patents from the 1930s to 1960s).

I stole time from my stern employ today and worked through the archive of French patents.

I'm not certain that the story about accidental discovery of duplex steel stands up (but that's the job of historiography, not patents).

I quickly found a patent for the enterprise at which duplex steel was supposedly discovered by accident, applied for in '35 and granted in'36, for "Leur structure comporte une proportion importante de ferrite à côté de l'austénite, ce qui leur permet de résister à la corrosion intercristalline après recuit entre 500 et 800 degrés C."

The same enterprise applied for a patent in '40, granted in '41, that is explicitly for what we today call duplex steel: "La présente invention est relative aux aciers inoxydables à deux phases: austénite-ferrite. Elle a pour buts ou résultats industriels de durcir les aciers de ce genre, c'est-àr, dire d'augmenter leur limite élastique et feur charge de rupture, sans en amoindrir sensiblement l'allongement, ni la résilience, ni les qualités de résistance à la corrosion."

The date of application of the second patent was in April 1940 and the grant in May 1941 (made public in August 1941). Big surprise. That period straddles the invasion that ends the Third Republic and then the start of Regime de Vichy, no?

I quickly searched the Swedish patents. I've not found anything that looks like duplex ss yet.

[skenn_ie]

Originally Posted by chrisr

my thoughts on chinese stainless chain : irrespective of the origin, if brand A is say half the price of brand B, i'm always suspicious of the quality. sometimes it doesn't matter...sometimes it does.

the chinese are capable of world class engineering when they want to. trouble is we in the west pay bottom price and then complain because we get bottom quality.

i would not automatically steer away from chinese ss chain, but i would stay away from any supplier that i could not verify as producing a quality product.

cheers,

A retailer in the UK asked a Chinese supplier if they could supply 316 fittings. The supplier replied "we can mark it however you want" !!!!!!!!!

[CaptainDanny]

Stainless steel chain is the best thing you could do in your life if you anchor in a muddy place. Mud falls off of stainless fast. It's also good if you don't like rust on your deck. You don't have to have all stainless just enough to cover the deck and down the hole a little bit.
You'll find all kinds of people warning you about dissimilar metals but the fact is anything galvanized will be gone long before dissimilar metal issues are anything to worry about. Just put a foot of it across your deck and you're going to be fine.
I have a 30-ft boat with 45 ft of stainless chain on each of my three anchors. you don't have to spend a fortune on chain to get good chain. The same chain that sells at West Marine for your kidney and first born can be purchased for about $3 a foot if you go to the right place. Should only be about twice the cost of galvanized. Just make sure if you have a gypsy that you get the right link to fit.

[sailorladd]

You might consider looking at prices of 316L stainless steel rather than the soon-to-rust industrial grade 304...

also hopefully when you get to a port or marina you hose off the salt water from your galvanized chain, it should behave better and last a lot longer.. galvanized chain has been used for a very long time and in my opinion it is stronger than SS...

[Nicholson58]

Living aboard in the Caribbean and anchoring every day.

Galvanized chain lasts about three years. SS will survive much longer. It is slippery. New galvanized is also slippery and doesn’t pile high but that doesn’t last long. We buy Italian galvanized chains in the French islands for half the cost of anywhere else. I have not priced SS yet but that may be next.

SS is not near the strength of good steel chain. Stay away from bad weather.

[moseriw]

Stainless seems to be the wrong way as the rupture load for a 10 mm galvanized steel chain ist 5800 kgs. SS rupture load is much less.

[thinwater]

Originally Posted by conchaway

The MAIN thing is make the the last foot or so that attaches to the boat should be LINE, NOT CHAIN! When your anchor is jammed on the bottom, you'll never get a rusted metal attachment loose! ( Yes, stainless WILL rust under the right conditions). Been there.

Better yet, just enough length that it will come up through the hawse pipe to on deck, so you don't have to crawl into a dark, bouncing locker in the middle of a storm. Obviously, this depends on the accessibility of the rode termination.

[CaptainDanny]

[QUOTE=GB32;3321647]Quote:
Worthless trivia: it’s the spruling pipe that goes into the chain locker, hawse pipe goes from deck overboard.
Sp. Spurling:

Just so you know, the two are synonymous. Not only that, they are the same thing.

[cromox Jeff]

Originally Posted by Departing2017

Ok, so once you've stopped laughing and rolling your eyes at my vanity and extravagance (probably justified, if you ask the Admiral), I have a couple of serious questions.


I have been exploring the option of upgrading to stainless anchor chain, and here's why. We do not have access to our chain locker from the deck, and our current chain (3/8" galvanized G4) makes a nice cone-shaped pile in the locker that fouls the hawse pipe long before we have the anchor up. This necessitates placing a crew member below in the V-berth to reach through a small opening in the bulkhead and manually stack the chain. Problem is, we're usually short handed and don't have a crew member to spare.


My understanding is that stainless chain being a bit more slippery won't pile itself into a cone. So first questions: Is this true? And do you think SS chain would solve my problem as described?


Next question. As I'm researching online, I'm running into huge variation on the price of SS chain. Around $2,700 for 300 feet on the low end up to almost $9,000. Nine grand is a non-starter, but the bottom end of the range might be worth it. I'm guessing the price difference boils down to Made in China versus Made in Not China. The sources for the lower priced chain at least appear to be fairly reputable marine retailers. How much do I worry about quality control on SS chain if it is made in China?


Thanks for sharing any thoughts.

Stainless steel chain ideal for anchor chain. The surface of the steel allows you to save space and achieve a better weight distribution in the chain locker. It also prevents the high piling that galvanized chain causes.

[cromox Jeff]

The outstanding surface of cromox stainless steel anchor chains allows you to save space and achieve a better
weight distribution in the anchor locker. It will also help with piling in the chain locker