Anchor Chain.....

[vyv_cox]

Vyv,

what is the 'stronger' chain material that you recommend to allow the chain size to be as small as possible?

The strongest that I am aware of in a galvanised ISO 766 chain is grade 70. This has the same composition as Grade 40, a bit more carbon and manganese than Grade 30, but it is heat treated and therefore more expensive. Paul Chandler bought Grade 70 8mm when refitting Lorne Rival instead of the Grade 30 10 mm that would otherwise be considered normal for a 38 foot boat. Grade 70 is rather difficult to purchase but I believe it can be ordered direct from Maggi in Italy, or maybe a specialist in UK.

Most Chinese made chain supplied by the likes of Bradney, William Hackett or any chandler supplied by Bainbridge, is nominally Grade 30 but found in my testing to be up to Grade 40 strength.

Jonathan Neeves is considering, and may have purchased, 6 mm Grade 70 for his 38 ft catamaran. This is in line with current thinking that it is better to have a heavier anchor and lighter chain than the opposite. There is a limit of course and this thread has highlighted that an all-rope rode (or nearly so) creates problems of its own.

 

[oldbilbo]

.....This is in line with current thinking that it is better to have a heavier anchor and lighter chain than the opposite.....

'Fraid I'm something of a plain ol' fashioned reactionary when it comes to h'ankering. IMHO it is better to have a heavier anchor AND heavier chain.....

There's nowt wrong with having/using a light anchor and light chain in light conditions. When conditions get really heavy, it's time for the really heavy tackle.

If you doubt that, have a look at Skip Novak's video ( elsewhere on this site ), showing him preparing the decks for heavy weather, and in particular at around 2:40. Note the size of his bower anchor as he manoeuvres it on a halyard down the forehatch. Oh, and the make......

[video]http://www.yachtingworld.com/specials/536047/skip-novak-storm-sailing-pt-6-preparing-the-deck[/video]

 

[srah1953]

I was going to raise this sometime and now seems as good as any. I've been reading a book, written in 2011, on boat manoeuvres by the editor of the German “Yacht” magazine. He says that outdated theories and stubborn prejudices often lead to uncertainty and incorrect buying decisions. He says a combination of chain and rope is best for holding an anchor. That way the strength of both systems is combined and weaknesses mitigated as far as is possible. He says that all chain increases weight in the sensitive bow area and, more importantly, causes peak loads, as when jerked about by the swell, not absorbed by the anchor which can then brake out. He says that the assumption of shock absorption by the chain has been disproved as the chain can be stretched taut, depending on the boat, in as little as 20 knots. He recommends to only use 10m or so of chain with rope for the rest.

Put that in your pipe ..

 

[NormanS]

We are all entitled to our (differing) opinions. And that's all they are, opinions. If you are happy with your own ways, and get good results, why change?

 

[Iliade]

Stick the current gear in the bilges for use if it ever gets scary. For the rest of your anchoring time use a danforth/fortress, a few metres of chain and a big bucket of blue poo or anchorplait if you choose to afford it. The rope will provide a good spring making anchoring quiet and secure, providing the anchor is good enough... (Hold tight! Here we go again... It's yet another anchor thread!)

For years I anchored with a slightly bigger boat than yours, which weighed next to nothing and had a high flush deck so therefore rode to the wind and gave the anchor (not to mention the crew) a really hard time in any sort of seaway, with a similar arrangement. Now I have loads of chain with a CQR on the end and anchoring is less secure, less frequently immediately successful (until I learnt the CQR drop technique!) and harsher. the only saving grace is I don't need to put a noise-deadening cloth around the cable where is passes over the bow roller etc.

The lighter ground tackle will be a lot easier to bring up, tempting you to anchor more frequently and the bows may ride to the sea better, keeping the boat dryer when sailing. Actually I was paranoid about this and used to keep my ground tackle under the cockpit sole, leaving the bows very light, so as to ride up the sea, rather than allowing every wave to sweep the deck.

 

[Scotty_Tradewind]

who's got the courage an' gonna answer or comment on those anchor posts then!

 

[NormanS]

who's got the courage an' gonna answer or comment on those anchor posts then!

What's the point? We've heard them all before.

 

[William_H]

From all the varying answers the answer for the OP is really up to him. Around here all chain anchor is fairly unusual except for bigger boats with power anchor winch.
Far more common is the short chain then rope. I would agrree that a bigger anchor especially if you are in mud is better than heavier chain.
Then much dpends on the boat. Is it bow heavy or is it a heavy boat anyway? Does OP just do picnic anchoring or does he want to be able to leave his boat on the anchor for short or long periods?
I have just a few metres of chain on a danforth and a pile of old rope on a light 21fter but then I can't rmemeber when I last anchored. So it is just safety gear. But on the other hand in a beat to windward in choppy conditions I like to get the bow down on my boat to stop it lifting and slamming in small waves. It seems to cut through the chop much easier.
So I suggest the OP remove the chain intact and fit a chain rope system and see how he feels after some use. Certainly if he is doing a voyage with critical anchoring expected then the chain might be well stored in the bilge. Certainly a lighter rope is easier to lift by hand. good luck olewill

 

[Scotty_Tradewind]

What's the point? We've heard them all before.

 

[vyv_cox]

I was going to raise this sometime and now seems as good as any. I've been reading a book, written in 2011, on boat manoeuvres by the editor of the German “Yacht” magazine. He says that outdated theories and stubborn prejudices often lead to uncertainty and incorrect buying decisions. He says a combination of chain and rope is best for holding an anchor. That way the strength of both systems is combined and weaknesses mitigated as far as is possible. He says that all chain increases weight in the sensitive bow area and, more importantly, causes peak loads, as when jerked about by the swell, not absorbed by the anchor which can then brake out. He says that the assumption of shock absorption by the chain has been disproved as the chain can be stretched taut, depending on the boat, in as little as 20 knots. He recommends to only use 10m or so of chain with rope for the rest.

Put that in your pipe ..

That statement is the result of the theoretical work carried out by Alain Fraysse, showing that despite people's convictions, catenary provided by massive weight of chain actually does very little to retain a boat at anchor. His theories were convincingly tested by the late Alain Poireaud, designer of the Spade anchor, who used only a relatively short length of chain in conjunction with rope as his primary rode. His boat was a Hylas 47 which he cruised extensively in Patagonia and other notoriously windy spots.

My view, which I argued with him many times, is that his arrangement is fine in empty anchorages, particularly in fairly constant wind directions, but in the crowded anchorages of Europe a rode consisting of mostly rope introduces many more problems that can be overcome by using all chain.

 

[JimC]

My boat is rather fine forward and I don't like to carry much weight there so I've opted to use most of the weight for the anchor and use a minimum of chain, in my case 10 metres. The only drawback I've found with this is that the boat wanders around more at anchor and if you're sharing a crowded anchorage this can be a problem. I'm now starting to experiment with using an angel of about half the weight of the anchor and first signs are that this is going to solve or greatly reduce the problem. The angel clips over the anchor rope with a big carbine hook and is lowered using a light line. When not in use it can be stored away from the bows.