Stupid questions about anchor chain

[LadyInBed]

Re: gypsy size

If you strip down the windlass and extract the gypsy, there should be some numbers stamped on the side. You should be able to get these cross referenced for size and type.

 

[hylas]

Re: SAFETY - believe me..

I have asked several magazines (in U.S.A., France, as well as PBO) to make a test of not only the "C" type links, but also the swivels and the various type of splicing Rope to Chain.. and this will give you the answer..

I did have a look in my documentation, but I was not able to find the documentation of these "c" connecting links.. but I know (from memory) that their Breaking Load Limit is MUCH lower than the one of the chain..

On the PLASTIMO catalog, the connecting swivel given for connecting an anchor to a 10 mm chain has only a BLL of 3 tons, compared to 5 tons for a 10 mm chain..

As far as I'm concerned, I will never use such a connecting link, unless I will have a very precise indication of the Breaking Load Limit given by the manufacturer..

 

[hylas]

Re: Following with Interest!

And PLEASE believe me, I have NO COMMERCIAL INTEREST neither in "C" links nor in chain or rope.. or any component of the mooring line.. but for my own boat I will never use such links..

 

[MedMan]

Re: chain versus Warp

As a liveaboard I am always interested in views on anchoring and I have read your thesis several times over. Much of it makes good sense, but nothing , not even your eloquence, would ever persuade me to abandon my 60 metres of 10mm chain.

I have a Simpson Lawrence electric vertical windlass that has a profiled hawse pipe just wide enough to take the chain. There is no rope to chain splice that I know of that could conceivably pass through it, ruling out a rope/chain combination completely. Furthermore, although we are all worried about anchoring in extremis, the most frequent danger of damage comes from swinging into another boat in today's crowded anchorages, not from being driven on to the shore. Rope requires a greater scope and a greater scope requires more swinging room that more often than not is simply not available.

There is a further factor in favour of all chain out here in the Med. Common practice is to lie bows to your anchor, stern to the quay, something we do regularly. We use 40 to 50 metres of chain in order to keep the anchor well clear of others and we can sleep knowing that our only contact with terra firma will not be sliced in half by the fishing boats storming out of the harbour at 0400 just a few metres off our bow.

It is true that chain puts weight in the wrong place, but so do my two extra water tanks, my sailmaker's sewing machine, my extensive tool kit, my spares and the spares for the spares, my charts and pilots and reading books and all the other 'essential' cruising gear I carry. Safety comes first in my book, not speed, so weight is not an issue. In extremis I have enough chain to veer to keep a catenary and, in any case, I always rig a nylon snubbing line to reduce shock loads.

 

[halcyon]

Re: SAFETY - believe me..

Out of interest I did a look at a chain firm's site, and it looks like a KENTER type joining shackle.
Shown as replacing a 'D' shackle as the modern way of joining anchor chains.
They give no tech specs, may need someone e-mailing a chain manufacturer for details if keen.


Brian

 

[LadyInBed]

Re: KENTER shackle

<A target="_blank" HREF=http://www.anchormarinehouston.com/Kenter.html> KENTER shackle spec </A>

 

[ccscott49]

Re: KENTER shackle

I have 5/8 chain, and the lionk is too big to go round my gypsy. But they are strong!! Not much use to the yachtsman though, starting at 5/8, thanks for the info.

 

[ccscott49]

Re: chain versus Warp

There is also no way I can use chain rope and may even put some more chain on! I only have 50 meters of 5/8 chain, but I think I may need more! I've had it all out a few times this year. But I need a new anchor anyway aswell.

 

[duncan]

anchor chain - a further confusion

following the earlier part of this thread through in my mind I was somewhat surprised to see in the Plastimo catalogue that for 8mm chain they quote 3200kg BS for calibrated and 2000kg BS for uncalibrated (but still short link) chain.
This is of course entirely inconsistent with some of the earlier posts and indicated uncalibrated chain to be a true 'second' or inferior product.
With a differential like this loosing a few % through the connector - c link or whatever - pales into insignificance!

 

[hylas]

Re: chain versus Warp

Hi Medman..
Yes I'm very familiar with this type of comments.. as well as the one about HEAVY anchors.. as these theories have been in use since so long now..

I also know that Galileo was nearly burnt for saying that the earth was round.. :0).. Luky I am.. since I have nearly no risks for explaining my theories on the Net.. :0)

I'ts just a question of time, but I already can feel the changes: - my anchoring theories about weighting the anchor's tip, about the right penetrating angle and the concave surface giving an higher holding.. are now well accepted and all tests have proved that I was right..

Don't be anxious.. if your hawse pipe is too nairow to accept the splice.. they are at least two solutions..:
The first one is simply to change it for a bigger one.. :0)..
The second one, as a Blue water sailor you should already use it.. I suppose that, when anchored, you never keep your chain on the gypsy of your Capstan, but you should use any kind of chain-riding stopper?? The Nylon rope should be attached to the chain either using a rolling hitch or a "Devil Claw hook" or a grab hook.. then pay out about ten meters of Nylon rope, this will give you the elasticity you need for your mooring line..

The danger of damage coming from swinging into another boat in today's crowded anchorages is another point. I fully agree that rope require a greater scope.. but also if you go back to the study done by John Knox (PBO August 2002) you will see that some anchors are very sensitive to a reduction of scope. One anchor tested gave only 45% of the maximum hold at scope 3 when some others still keep 70 to 80% of the maximum holding.. then I will also suggest to have a line consisting of some chain, rope and an anchor not too sensitive to the reduction of scope..

If you have an anchor with a better holding.. one danger also comme from others boats which are still equiped with old technology anchors and which will drag onto your own boat.. Sailing is always a question of compromise..

I spent ten years sailing full time the Med, from Gibraltar to Ashkelon in Israël.. I was also used to anchor bow to.. as this will give more privacy.. I was using my stern aluminum anchor with 5 metres of chain and then Nylon rope.. Like you, trying to keep my anchor well clear from others anchors, and in ten years, I didn't have once my wrap cut by another boat..

But at the end of your question.. you also give the right answer.. " in any case, I always rig a nylon snubbing line to reduce shock loads."..

So, we fully agree with each other..
Fair winds and peacefull anchorages..

Alain

 

[hylas]

Re: \"C\" links - the real figure!

I just receive today the latest issue of PLASTIMO catalogue and page 211 (spanish edition) you can read the CMU (maximal Utile charge) for te "C" links:

Diameter 8 mm - Ref: 13250 - CMU 150 kg
10 mm 13251 200 kg
12 mm 13252 700 kg
14 mm 13253 1100 kg

Although you can use a 12 mm "C" link on a 10 mm chain, its strenght will only be 700 kg compared to 5 000 kg for the chain...

 

[pvb]

Apples and oranges...

Think you're getting a bit confused here, and you're certainly trying to compare apples with oranges by comparing the working load of a connecting link with the breaking strength of the chain!

Like chain itself, connecting links have different mechanical properties according to what material they're made from. So, just because they look the same doesn't mean they behave in the same way.

West Marine (as well as many other US suppliers) rate their connecting links to be about the same strength as the chain. This also applies to stainless steel connecting links. Bearing in mind the litigious nature of the market over there, and therefore the caution they have to exercise in their marketing claims, I'd be happy to regard the figures they quote as fairly reliable.

It's possible that the Plastimo products are inferior in manufacture to other connecting links. Incidentally, you should note that Plastimo quote SWL (safe working load) at 50% of the breaking strength, whereas the Americans tend to quote a WLL (working load limit) at only 25% of the breaking strength.