chain dimensions specification


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owenp
owenp
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Dear all,

i m currently renewing the windlass and chain on my boat , Danú.
boat is 17.3 tonnes , 13m , steel.
looking at various information i have read it seems that given the weight and length that 10 mm g40 calibrated chain would be suitable . I am thinking of putting in 80 m chain.

does any one have any advice on whether to go to 12 mm or 10mm ?

Regarding the windlass, I like keeping with the manual anchor idea yet most windlasses available are electric.
There is a company still producing simpson lawrence seatiger 555 windlasses (SLSPARES UK) which seem to have a good reputation.

has anyone seen these in action ?

great to hear your suggestions / opinions on this.

thanks

Peter Owens , Galway , Ireland
Dick
Dick
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Hi Peter,
I am currently writing an article on the choosing of chain, and would be happy to send you a copy off line if you send an email to me at Alchemy128(at)gmail.com.
The gist is to choose chain by strength and not by weight. The argument for weight is it produces catenary. This argument falls apart in near gale conditions (when you need catenary most) when the chain regularly gets 2-blocked (stretched link to link) in most reasonable scopes. Your snubber then becomes crucial in absorbing and averaging loads as the catenary is for all practical purposes non-existent.
I have a similarly sized boat (12.2m and 16+ ton) and am quite content with 5/16 inch G40 from a good manufacturer. I have 80m and will get 100m when I replace it. My chain is 16yo and has been re-galvanized once and has served through thousands of nights at anchor and many gales.
I would suggest 10mm G40 (plenty strong) from a good manufacturer and put your weight and money into a good designed anchor. Mine is a 35kg Spade and I have been using Spades for almost a decade now and think it is the top bower available presently.
We spent a week in Galway this last summer and the whole summer on the west coats of Ireland. Marvelous.
My best, Dick Stevenson, s/v Alchemy
Simon Currin
Simon Currin
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Peter,
I know you are planning to use this in Greenland 's testing fjords. I would definitely go for a 100m if you have the room and using a smaller, high tensile, chain may give you enough locker room to do this. That 's what we did and kept our old chain for backup in case we lost bower for any reason. Also, with long chains, heavy anchors and solid cold winds I can 't think why you wouldn 't want a powered windlass. Presumably to keep your crew fit for those big wall climbs?
Simon
Dick
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Hi Peter,
If heading out of Europe to deep water anchorages and the type of challenges that Greenland is likely to have, then I very much echo Simon 's advice for 100m I would also believe a powered windlass (money aside) to be considered a safety issue. Sometimes, in a midnight fire drill, one needs to get the anchor handled quickly. Pumping a long handle on heaving fore-deck for periods of time is a recipe for an accident.
My best, Dick
Simon Currin
Simon Currin
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Peter I am not sure if you have already seen this thread which discusses G70 chain at some length. https://www.forum.oceancruisingclub.org/anchors-and-anchoring/760-g70-anchor-chain.html
owenp
owenp
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thanks Dick and Simon for your replies.

I think now that 10 mm of G40 is the best option. I can see the logic in the G70 and 8mm though but we have plenty of space in bow for 100 m .
re windlass I can see that not many share my view on manual ones! i suppose i am thinking of simplicity over another electrical setup. cost is a consideration with the lofrans electric windlass for our boat coming in at €2500. Also and perhaps a bit on the masochistic side, having used manual windlasses for ever , they are one of the few ways on a boat to give the arms a work out ! but repeated anchoring in stiff conditions is not fun i admit. Will think a little more on this one.
all the best

Peter
Dick
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Hi Peter,
You bring up another safety issue with having a powered windlass that I neglected to mention before. I know you are clear, but I wish to underline it for others who may be reading. There is certainly an argument for simplicity, less expense and for exercise, but it should be kept in mind that one of the appreciations most mentioned by those who switch from manual to powered winches is the ease with which they are able to re-anchor. First or even second choice anchoring spots do not always feel right when settled and to quickly and easily adjust can be a good thing. That said, adding a powered windlass is no small project.
My best,
Dick Stevenson, s/v Alchemy
Dick
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And at the risk of belaboring a point, this was started by considerations of anchoring deep. For those considering this dilemma with windlasses, one should go somewhere and either anchor deep or go to deep water and drop your bower and 25-30 meters of chain over the bow and then use the manual windlass to retrieve. Even my quite powerful electric windlass starts to strain at this level of weight and retrieval time increases a great deal.
Enough already, Dick
owenp
owenp
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Hi dick

thanks for your responses. i think i am getting around to the electric idea. The last person i talked to about all this told me to throw away the cqr, or use it as a garden ornament along with the fishermans and get a spade or vulcan ! i know this brings up a new topic on choice of anchor. Whats your thoughts on this?
all the best

Peter
Simon Currin
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Peter,
Where you are heading (Greenland) there 's loads of rock and kelp so all anchors will have limitations. We use a 45kg Manson which is similar to the ubiquitous Rocna. Might be worth keeping you Fisherman 's to cope with the kelp?
Simon
GO

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