Slightly over the top anchor chain

NormanS

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All multihulls are equipped with bridles, which are two snubbers joined together. One concept fits all multihulls (and can be used on beamy monohulls). Mine start at the transom, and others do exactly the same thing.
That's good. It works for you. I don't need to.
 

iamtjc

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With all this talk of 6mm Grade 70 chain being better for smaller yachts I thought I would price some up and consider a change from my 8mm chain (27ft boat < 3 tonnes).
Despite a lot of time googling, I couldn't find any UK source of 6mm Grade 70 chain. Anyone have any suggestions?
 

Tranona

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With all this talk of 6mm Grade 70 chain being better for smaller yachts I thought I would price some up and consider a change from my 8mm chain (27ft boat < 3 tonnes).
Despite a lot of time googling, I couldn't find any UK source of 6mm Grade 70 chain. Anyone have any suggestions?
It is not readily available although member Zoidberg bought some recently and has the supplier details. However it is really not necessary for a typical 27' boat. Grade 40 which is widely available is fine. Grade 70 is suggested if you intend replacing 8mm on a boat in the 10-13m size range. Even then from a strength point of view there is still a good margin. Just as important is to check the connectors - shackles and pins.
 

Neeves

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Gunnebo make a galvanised G80. In order to achieve this strength they have made a link Xmm + 10% - which may not fit on some gypsies. If you hand retrieve not an issue. Their market is aquaculture. If you go into their website you can find it. A slight contradiction to Tranona's post - the chain is readily available - under certain conditions...read on.

I believe, as Tranona mentioned - Zoidberg bought some from a local distributor, send him a PM. Gunnebo is now part of Crosby and Crosby a part of Kito. There are lots of options for connectors, Omega links, hammer locks or shackles - I've used them all they all work to a greater or lesser degree. I recall Zoidberg's biggest problem was that the chain is sold in a fixed length, 100m?, and Zoidberg found someone, relatively easy and quickly to share in the 100m

Again as Tranona says - check with Gunnebo which connectors fit the chain, ask for the dimension and ensure the connectors fit your anchor. Another source for Crosby shackles is Tecni, I think based in or near Bristol.

You reduce the catenary effect by using smaller chain, its lighter, and you should consider replacing the absence of catenary with a snubber.

I 'made' my own HT 6mm chain, Gunnebo had not released their G80 + 10% and I have an article I can send to you if you send me an email address via PM, I'd include details of snubbers at the same time - though if you search here, on YBW, there are plenty of threads. Sadly I cannot make a rode for you - I live in Australia - but I have made for a couple of YBW members from the UK who happened to be in Oz.

If you hand retreive you will find the Gunnebo chain a revelation. So easy to handle and you will have more room in the chain locker - though you might opt for a longer rode.

Jonathan
 

Neeves

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Here we go

https://www.gunneboindustries.com/Lifting/Products/Aquaculture/Hot-dip-galvanized/Chain-KLZ-HDG/

Look for the 6mm+ 10%.

If you have a windlass and you already use 8mm you would need a new gypsy. 6mm. chain will not fit an 8mm gypsy, and vice versa. Gypsies are extortionate and it is simply too expensive to buy both a new gypsy and new chain - unless you are really flush. When we changed we bought a new windlass - the old one was well used and tired. We optioned a Maxwell, I think coded an RC8-6, - like chalk and cheese to the windlass it replaced.

The exercise is best conducted when you buy a new yacht and then you ensure all the equipment, chain, windlass, anchor, connectors are all compatible for both fit and strength. None of this is difficult.

Some gypsies are more accommodating of different link sizes than others. You would need a short length of the Gunnebo chain to test, say 1m. I know that some windlass makers are looking at this very issue and are actually testing the Gunnebo chain in their gypsies - but I have not been appraised, yet, of any results.

Again as Tranona mentions - look at 6mm G40, it will be more than strong enough, cheaper and if you use a snubber the actual loads are significantly reduced. Again check that the connectors fit. We used High Tensile 6mm chain with the same strength as the G30 8mm chain it replaced - our yacht was a 38'x 7t cat with the windage of a Bavaria 45 (and its windage that is the killer)


A complete aside - if you strip out the keel ballast of the Bav 45 the 2 yachts, 38'cat and 45' mono have a similar weight, so similar amount of glass fibre and resin, hence similar windage as the accomodation volume will be more similar than different (though I measured windage slightly differently).

Jonathan
 

doug748

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With all this talk of 6mm Grade 70 chain being better for smaller yachts I thought I would price some up and consider a change from my 8mm chain (27ft boat < 3 tonnes).
Despite a lot of time googling, I couldn't find any UK source of 6mm Grade 70 chain. Anyone have any suggestions?

Yes, theories are great things, but fancy chain is an irrelevance for most.
Tho , as above, in your case you could probably go down to bog standard 6mm without losing too much sleep.

.
 

Neeves

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What for?so you can store extra suff? Weight?

But that's weight isn't it...?

Fenders don't weight very much, but take up an inordinate amount of room. Being able to store fenders in the bow frees up space in the cockpit for items that are needed more frequently.

If you have, say, 50m of 8mm chain it weighs 72kg, you can carry 70m of 6mm chain 56kg - saving weight and have a longer rode (and still leave room for a fender, or two :)

A win win?

But, if you have these choices when you buy a new yacht - your use of the battery will be reduced, the windlass will cost less (and also be slightly lighter), the wiring will be smaller and your sailing performance - potentially better.

I know you now need a snubber - cheap as chips.

A win win win?

You sacrifice nothing - but have a better sailing experience - you drag yourself from the 'technology' of the mid 20th century, or earlier, into the 21st century. :).



If you read threads and posts from as recently as 20/30 years ago - these concepts were simply not discussed - you, obviously, would be surprised - the changes for many are simply not a point of discussion, they cannot understand why they did not downsize earlier. Dashew was an early proponent, he championed gal G70, Starzingers (2 circumnavigations) championed snubbers (based on retired climbing rope). Since then access to different alloys and galvanising techniques have opened new opportunities. Oddly - snubbers have not improved - we still rely on nylon - but have found that a 'cat's cradle' of nylon works a dream. :)

Jonathan
 
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Neeves

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Yes, theories are great things, but fancy chain is an irrelevance for most.
Tho , as above, in your case you could probably go down to bog standard 6mm without losing too much sleep.

.

Who would have thought that G40 x 6mm, G70 chain would be described as fancy - the lifting industry and the oil industry have discarded these qualities (some chain makers no longer make these grades) - the focus now is G100 and G120. G43, and G70 has been used for the anchor rode by Americans for decades. Jimmy Green has been selling G70 for some considerable time now. I would agree Cromox (a G60) quality is 'fancy' but is used by some (its absence of penetration to the market is simply a factor of cost - not the advantage of strength, reducing weight etc).

Cromox - irrelevant? that's a major product line for Kettern Walder, as is galvanised G70 for Jimmy Green and Peerless in America.

Jonathan
 
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