All Chain versus Chain/Rope?

[Sans Bateau]

This article may be of help to anyone considering anchors and warps. Take a look at page 5. We carry 25 metres of chain plus 50 metres of 18mm octaplait and a Delta anchor, all oversized for a 35 ftr, in fact they are 'suitable' sizes for a 40+ ftr.

http://www.bethandevans.com/pdf/Anchorsteps.pdf

Beth and Evan Starzinger are livaboards who have huge experience, read more about them here:

http://www.bethandevans.com/

 

[craigsmith]

I currently have 30m chain + 60m 16mm rope and a windlass that isn't particularly happy pulling in the rope. I was going to buy 45m chain (45m being a regularly used length) but all the arguments point to having less chain say 10m and the rest rope. I quote Alain Hyles below.

"The main and ONLY advantage of the chain is that it is the only and perfect means to avoid chafing of the anchoring rode on agressive sea beds...

Except for this point, chain has all the disadvantages..:
Stored in the bow chain locker, it adds a heavy weight in the last place you want one. When deployed, chain is actually working in the the opposite way to the way it should work:

with light wind, it gives a perfect horizontal pull to the anchor and the best holding.

with moderate wind, its weight and catenary effect give a perfect shock absorbing effect.

As the wind builds up, the chain will become straighter (and this with as little as 25/30 knots of wind). The pulling angle will increase and as a consequence, the holding of the anchor will decrease.

When the shock absorbing effect is most necessary, the "bar tight" chain will not allow this to happen."

I do use a snubber - which is about 5m to a centre deck cleat, but the gurus (also Anchorwatch) say this is inadequate to stop shocks to the anchor with an all chain rode.
Has anyone here used less chain and more rope? I'm used to seeing charter boats putting out 65m chain! Comments?

The answer depends on the boat size and scales accordingly. For your boat, this answer is more or less correct. Chain becomes more attractive with larger vessels.

You should also consider the practicalities of pulling in your rope and transitioning from rope to chain, depending on your windlass and gypsy, particularly in deep water where there is more weight on the rode.

How shocking, as evidenced by some of the reactions in this thread? Despite the mysticism that seems to surround these topics, they are in fact not as complex as they might appear. They are simply complicated by 1) a lingering conservative traditionalism which stems from the old days of a) an absence of small yachts, b) poor performing anchors designed more for practical manual handling, and c) poor quality ropes; and 2) an ignorance of how the situation scales from a small dinghy to a large ship.

If your interested in details of optimal ratios of chain:rope etc, Peter has an in-depth article on this exact subject:
www.petersmith.net.nz/boat-anchors/catenary.php

 

[Gypsyjoss]

This article may be of help to anyone considering anchors and warps. .
http://www.bethandevans.com/pdf/Anchorsteps.pdf

Thanks for all your replies and discussions. As a result, and after reading the very useful article, above, I'll keep my existing arrangement for another season at least but I'll turn my chain and rope around and resplice so that I'm using the least used, and improve my anchoring technique.
If I have problems running the rope through the gypsy and the chain is ready for change, I'll go to mostly chain. And if I have problems holding despite correct technique and scope I'll change the anchor - probably to a Rocna or Bruce (if I can find one). It is interesting that Beth and Evans exchanged their CQR immediately for a Bruce.

Does the CQR have a poor reputation for holding in Mediterranean waters?

 

[craigsmith]

It has a poor reputation holding anywhere.

 

[Gypsyjoss]

CQRs are useless?

It has a poor reputation holding anywhere.

Well, you would say that - with your affilliation!
How come so many boats have got them. I haven't checked prices but surely they are far more expensive than say a Bruce. Are there no loyal owners out there! Oh dear. there's a challenge!

 

[sailinglegend420]

[QUOTE...........

http://www.bethandevans.com/pdf/Anchorsteps.pdf

[/QUOTE]

A good article but we need a book on the subject.

It would seem that amongst all the arguments about catenary and rodes what is needed is good "snubbing". We have always used the largest size 4 Forsheda mooring compensator you can buy, and 4 m of warp. After 3 years as liveaboard we have never dragged, even in several Force 8 situations. Last year in Majorca we were in a tight anchorage in 6m of water with a Delta anchor and only 30m of all chain when a Katabatic wind blew up with sustained 40 knots of wind. All the 7 other boats dragged their anchors. We have 100m of chain but did not have the space to deploy.

We have never seen anyone else use these snubbers on the anchor chain, and we have never been able to buy another size 4, which is a shame since our size 3 ones we use for mooring during winter keep breaking.

 

[Deleted member 36384]

Forseheda Mooring Compensator Source

Size 4 Forsheda Mooring Compensator available here on mail order: -

https://www.svb.de/html/Docklines.html

 

[Chris_Robb]

Well, you would say that - with your affilliation!
How come so many boats have got them. I haven't checked prices but surely they are far more expensive than say a Bruce. Are there no loyal owners out there! Oh dear. there's a challenge!

I would heartily agree with Craig. I am an ex CQR user, bought a Manson Supreme 3 years ago. There is absolutley no contest - Rocna is certainly as good, if not better (for Craigs benefit) My CQR is now an ornament in the Garden, I would not even give it space on board as a spare - they are that bad in comparison. Why are they popular? Dunno - perhaps CQR lovers have not used anything else, so just are not aware. I would also warn against the modern Bruce copy, which seems to all accounts nothing like as good as it original "Bruce".

 

[Quandary]

Looked into this (Manson V Rocna V Spade thoroughly) before buying a new main anchor last year, went for the Manson for the following reasons
1 a bit heavier in each size
2 looked like better galvanizing
3 considerably cheaper in the U.K. enough to buy quite a bit of extra chain or rope
4 was able to ascertain where it was actually made
5 preferred to contibute to the New Zealand rather than Chinese or American or wherever economy ( retailer was uncertain which plant the Rocna came from but guessed China via Ireland)
(Spade was ruled out on price/availability at the start)

but why can no one in the UK make a competing anchor, importing lumps of galv. steel wrapped in bubble wrap from the other side of the world makes no sense to me.

 

[Tranona]

but why can no one in the UK make a competing anchor, importing lumps of galv. steel wrapped in bubble wrap from the other side of the world makes no sense to me.

I agree with your sentiments. I believe even Deltas are made in China now - can't be many products that are simpler to make. Notice there are now Delta copies coming on the market just the same as there are CQR and Bruce copies and likewise much cheaper than the genuine article.

 

[Chris_Robb]

I agree with your sentiments. I believe even Deltas are made in China now - can't be many products that are simpler to make. Notice there are now Delta copies coming on the market just the same as there are CQR and Bruce copies and likewise much cheaper than the genuine article.

But how strong are they..... We all know how weak some of the CQR copies were compared with the forged real CQR. You sometimes get what you pays for - or rather leave it behind on the ocean floor - hopefully with your boat not on the rocks!

 

[Murph404]

Thanks for all your replies. Should've given more info - must update my profile! Boat is a Sadler 32 out in the Aegean (into 2nd season, didn't have a windlass on previous boat)-
So no tides, rarely crowded anchorages. Racing is rare out here!
Typical depths 2 to 8 metres.
Anchor is a 35lb CQR (might buy a Rocna next year).

Is part of the reason for having all chain the positive drive given by the windlass?

I have a Centurion 32 which I have 12 m of 8mm chain with 50 m of 14mm on a Bruce anchor. I have used this set on the south Coast of the UK and have never dragged.
only place I found it tight was Cowes week Osborne bay when it was packed.

 

[Neeves]

Murph,

Welcome to the forum

The thread you have resurrected is over 10 years old?!!

Some of the people who posted are still around and active, others have disappeared (for a variety of reasons)

Jonathan

 

[Kilo]

Whilst in strong winds the chain rode may get close to being straight, it wont stay permanently like that cos as the wind varies so the boat moves. But in the end, all you are doing is changing the boats kinetic energy into potential energy by raising the chain and chum hopefully before the chain rode becomes bar tight.

Just been playing with some numbers. Ignoring the water resistance as the chain is straightened, the kinetic energy of a 5 tonne boat moving at 1 kn ( and I would have thought that the movement under wind would be a lot less quick) is easily absorbed by lifting 100lbs of chain about 12ft. Which is to say that the rode you put out for your 5 tonnes boat in a depth of 8m at a 4 to 1 scope will absorb the 1 knot sheer.

Interestingly, adding a chum mid way down the rode is approximately twice as effective as adding the same extra weight of chain to the length of the rode.

I like your calculation though couldn't have done it myself, not without hrs of head scratching & poor assumptions, ashamed to say my physics came to a halt after o levels.
Anyway, is there a formula - simple - for those of us of the physics challenged persuasion - to give the optimal weight of the chum?
Maybe also a formula to prevent the split infinitive too ?

 

[RichardS]

I like your calculation though couldn't have done it myself, not without hrs of head scratching & poor assumptions, ashamed to say my physics came to a halt after o levels.
Anyway, is there a formula - simple - for those of us of the physics challenged persuasion - to give the optimal weight of the chum?
Maybe also a formula to prevent the split infinitive too ?

I suspect that Bosun Higgs might well have "passed over" a decade ago.

Richard

 

[Kilo]

I suspect that Bosun Higgs might well have "passed over" a decade ago.

Richard

Oh dear, thanks for the note.

 

[Kilo]

I suspect that Bosun Higgs might well have "passed over" a decade ago.

Richard

Bosun Higgs, great name, hope he had a sense of humour as all that comes to mind now with the resurrection of the thread & my reply to his comment are many v irreverent puns, especially at this time of year ?