Anyone ever broken an anchor chain?

[J Neeves]

Snubbers are a consumable and should have an anticipated life of 1-2 years. They should be chosen to maximise elasticity, not for their ultimate strength. But its a balance, it obviously has to be strong enough but not so strong there is no stretch. If they do not fail say at around 2 years then you do not anchor frequently or they are too strong and not elastic enough. If your snubber is less than 5m (of available cordage), it is not offering sufficient elasticity - ideally you should be looking for 10m. The only way to judge a snubber is by trial and error as the windage and hence load developed for every yacht is different (we all have different windage for boom, spray hood, dodgers and high rise developments on the transom). A snubber is not there to replace any part of the rode - it simply acts in a support role. So lock off the rode to a strong point - snubbers do fail, unless you retire them to schedule.

For an average AWB of around 45' and about 10t then a 12mm x 10m nylon snubber is about right upto about 35 knots, beyond 35 knots (actually at the masthead) you should be thinking of 14mm to 16mm. For a beamy yacht, say a Moody, I would look to set up a snubber as a bridle - still 10m each side. But its trial and error, both keels and windage impact snatching and all yachts are different. We use 2 x 11mm x 10m lead climbing rope on a cat with the windage of a 45' Bav (though we are obviously lighter, 7t and only have mini keels).

If it is impossible to obtain certification on a component you think critical then I would suggest the obvious - buy from a reputable, named, manufacturer and buy the next size up. Check for deterioration and retire when doubtful. Your yacht will be worth slightly more than the cost of replacing a piece of cordage in the rode.

Jonathan

 

[robertj]

Maggi offer a test certificate after proof loading the length bought. It adds about 20% (from memory) to the cost of the chain. I have no experience of others making the same offer but I have a dim memory that Bradney would do it some years ago.

What chain do you use vyv and where is it available from please?

 

[OldBawley]

I think one reason we do not hear of stretched or broken chain, bent anchors, failed swivels and shackles is for the very simple reason most people do not allow themselves to anchor where stresses are likely to be high. Most will not leave home if the conditions are to be very ordinary - one idea of sailing is that its a pleasure and relaxation from the rest of life - the last thing people want is to put their ground tackle under load. I also suspect that those that are living on their yacht, whether it be used as a floating caravan or whether they cruise long distances, choose ground tackle with some care - they use better anchors, buy rated shackles either use Kong swivels or no swivel and buy chain from a reputable source and/or even over strength chain. I also think these liveaboards take notice of forecast and when 'Storms' are forecast move to somewhere where the winds will be much less than Storm Force 10 - not to move and endure Storm Force 10 looks a way to ensure you do not sleep.

What is noticeable is that the reports of broken chain have come from a mooring environment, where the vessel could not be moved, or for a failure in the weld. The former might be under specified or old chain but the latter would and should have been identified by a simple Proof Test (and for belt and braces - maybe Vyv's twist test).

There is an underlying suggestion that Proof Testing is not the norm - and if this is the case, what assurance do you have there was any quality control at all. To me a certificated chain gives some assurance there was some form of QC, the absence of a certificate (and you will not know unless you ask) raises questions - which you can ignore if you want - we are all still able to make that choice. Vyv's research suggested most G30 chain in the UK was of a quality near G40, but he did find some questionable, or less good, product. As Chinese chain is not marked, except for CMP Titan, i do wonder how you know if its the largely good stuff or the questionable stuff. I think Bradney's should be thanked for their diligence and people take advantage of what they offer. In the Med, buy from Maggi?

But if you are a fair weather sailor, like us - I am sure your chain will be safe if you steer clear of anchorages suffering 50 knot winds and always use a snubber.

Jonathan

Correct.
Just now I use a friends mooring. Seeing the whether forecast, I will be moving this morning.
39 kn prediction for tomorrow, I move the boat 300 yards and use my own anchor and 60 m of chain.
I don´t like a mooring in hard wind. No better than a long chain. Also the new spot is more protected from the katabatic winds.
Thunderstorm predicted, so a second anchor is laid to keep me in deep enough water during the passing of the thunderstorms. ( 360 ° wind veer )
Just 2,5 m of water on the anchor spot, very good holding. Just 100 yards behind a big eucalyptus forest. Five meter snubber with incorporated oversized rubber snubber.
Two winters ago my original 35 lbs CQR dragged 30 yards in two days on the same place. Normal for a plough anchor.
A few nights of bad sleep, the noise and movement of the boat can be rough.

 

[Rivers & creeks]

And why don;t we ask for it? Because there isn't a problem, that's why. Where there is an established problem, as with through hull fittings, we get picky but where there isn't, as with chain, we don't.

Last time I had to buy fully certified M6 washers for aircraft use, they cost about a fiver each.

We don't ask because we're British and it's rude to doubt someone's word. Next chain I get I'm asking for a certificate, why not? When I go into a take away their hygiene certificate is displayed for me, when I go into an office or factory, their public liability certificate is on display. Seems the single most important safety item on my boat - anchor and chain - deserves at least the same pre-purchase rigour as the burger I have for lunch.

 

[JumbleDuck]

Seems the single most important safety item on my boat - anchor and chain - deserves at least the same pre-purchase rigour as the burger I have for lunch.

That's why I buy my chain from a chandler I trust.

 

[vyv_cox]

What chain do you use vyv and where is it available from please?

My current chain was bought in Corsica and is either French or Italian-made. Its galvanising was poor, failing in three years despite being end-for-ended. I had it regalvanised at BE Wedge, subject of a YM article.

If I was buying now in UK I would probably buy locally to save carriage, from a chandler supplied by Bainbridge. They are a big buyer from China, where some excellent chain is made. I would certainly try my bend test to ensure the welds and galvanising are good. Alternatively, Bradney have always been reliable, (and did well in my tests) particularly if they will provide a proof test on the length being bought.

 

[prv]

Alternatively, Bradney have always been reliable, (and did well in my tests) particularly if they will provide a proof test on the length being bought.

They did on the one I bought.

40m of which, incidentally, will be for sale very shortly. Nothing wrong with the chain itself, but I got a bit enthusiastic in choosing the ground tackle and weighed the boat's bow down too much

Pete

 

[OldBawley]

On such a certificate, is there a way to know if the certificate is for exactly your chain or is it just a piece of paper? Are there identification numbers stamped into the chain ?

Before been a chandler I worked 25 years on a shipyard doing quality control. Have seen and done some qualification stunts.

 

[JumbleDuck]

On such a certificate, is there a way to know if the certificate is for exactly your chain or is it just a piece of paper? Are there identification numbers stamped into the chain ?

That's a very good question and is why I would not be bothered about certification unless there was a solid paper trail and identifying marks linking the document to the length of chain I had bought. Anyone can photocopy a certificate or stamp a grade number on a chain.

 

[OldBawley]

Fabricating chain is a fully automated process. The machine rattles and spits out chain. Cheap.

Certifying is something different. People have to do it. If it was Germany, qualified people had to do it. Herr Doctor diplomingenieur .
I have worked with such gentlemen. They ware Lloyd's or German equivalent.

One of these Doctors told me that 95% of all certificates ware never read. Just a piece of paper to file. In case of.

 

[JumbleDuck]

Certifying is something different. People have to do it.

I earned my living doing tensile testing at one time. In liquid nitrogen, which adds to the fun.

 

[vyv_cox]

Fabricating chain is a fully automated process. The machine rattles and spits out chain. Cheap.

Certifying is something different. People have to do it. If it was Germany, qualified people had to do it. Herr Doctor diplomingenieur .
I have worked with such gentlemen. They ware Lloyd's or German equivalent.

One of these Doctors told me that 95% of all certificates ware never read. Just a piece of paper to file. In case of.

In modern chain-making equipment a proof test is carried out length by length, I believe about a metre at a time. If it fails the machine stops. Proof tests should be 50% of MBL.

 

[OldBawley]

Modern technology never stops to amaze me.

 

[JumbleDuck]

In modern chain-making equipment a proof test is carried out length by length, I believe about a metre at a time. If it fails the machine stops. Proof tests should be 50% of MBL.

That sounds like a good reason to trust the makers and not worry about certificates. Not least because you'd need 50 (or possibly 51) of them for a 50m length of chain ...

 

[charles_reed]

That sounds like a good reason to trust the makers and not worry about certificates. Not least because you'd need 50 (or possibly 51) of them for a 50m length of chain ...

Quite a circular argument, this one.
Why bother about a free certificate? If it's free it must be worthless.
There's a U-Tube post about a Chinese chain-maker and it actually showed the test taking place (but not for every link)

 

[macd]

That sounds like a good reason to trust the makers and not worry about certificates.

No it doesn't. It sounds like a good reason to trust the makers using "modern chain-making equipment", to quote Vyv. My guess is that many chain plants, perhaps particularly in Europe, will have pretty antiquated equipment. That's no reason their chain will necessarily be sub-standard, but some of us would prefer some evidence either way.

 

[JumbleDuck]

No it doesn't. It sounds like a good reason to trust the makers using "modern chain-making equipment", to quote Vyv. My guess is that many chain plants, perhaps particularly in Europe, will have pretty antiquated equipment. That's no reason their chain will necessarily be sub-standard, but some of us would prefer some evidence either way.

That's fine, as long as you accept that it will cost you a substantial amount of money for proper independent testing. Manufacturer's tests aren't much use - if you don;t trust them to make the chain, why would you trust them to send you a correct certificate? It reminds me of the offers in the back of Radio Times designed to part senescent grandparents from their pensions: "Buy our dambusters plate. It comes with a certificate of quality".

When I was at primary school they tried to get me to sing "Jesus loves me / this I know / for the bible/ tells me so" but I never bought it - at the age of 6 I could spot a circular argument and spurious appeal to authority ...

 

[J Neeves]

As Vyv points out modern chain machinery measures Proof Load as part of the process, older equipment may not have the facility, which would you rather have as your source of chain? Break testing is commonly done off the end or beginning of a batch run. Which would you rather have, a chain with no check or a chain with a check?

The batch number is on the drum from which you buy the chain, not on the chain itself. Which would you rather have a chain where no certificate can be made available or one that links your chain to that batch number.

The test certificate should be part of a standard quality control process, which would you rather have a certificate at least indicating they can spell quality control or nothing.

The certificates are free.

We have trustworthy chandlers in Australia, I ordered chain for testing, it came with the mark of a competitor to the supplier I had requested. Fortunately the chain was marked, on the link and I had a free length of chain to support the cause. The chain I wanted was rubbish, the chain I received by mistake was consistent with 2 other samples I had bought independently.

Vyv raises an issue - complaints about chain breaking are not common, (but there are enough here to raise questions as to how a buyer can protect themselves - if they so desire some peace of mind, accepting the answers are not perfect). Most complaints about chain are to do with lifespan - how long will the gal last? I am not aware of one chain maker nor one chandler that sells chain with a gal thickness - yet this one piece of data determines the chain's useful life (especially as chain has so few reports of failure through breaking or stretching).

So, given that most chain today is safe, the one critical determinant of quality (or potential lifespan) is missing.

Jonathan

 

[Rivers & creeks]

That sounds like a good reason to trust the makers and not worry about certificates.

JD, I think we got what you were saying the first time, repeating it in each of your posts doesn't make it more convincing. We get it, to you a certificate is worthless.

 

[JumbleDuck]

JD, I think we got what you were saying the first time, repeating it in each of your posts doesn't make it more convincing. We get it, to you a certificate is worthless.

Thanks. Have you got Mr Neeves's message too? In case not, it's that without a photocopied piece of paper we are All Going To Die.