What chain do we have here?

SHUG

SHUG

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Thinking of installing a new windlass but I am having difficulty in establishing what the present anchor chain actually is. I have looked at Lewmar charts and Bradney chain but I can't get a good match.
Here are the average dimensions:

d, chain thickness, average….12.6mm
p, link inner length, average…36.1mm
w, link width, average………..45.7mm
L. overall link length. Average..60.4mm

The conclusion may be that its agricultural chain but I'd appreciate any help you can give.
 
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Presumably it's some form of standard 1/2" chain. I just went and checked some (galvanised) chain that I have in my shed.
The equivalent sizes are:-
Thickness.............12.9mm.
Inner link length....37mm.
Link width..............44.5mm
OA link length........61.9mm.

The sizes are pretty similar, but unfortunately I've had this chain for a long time, and don't know what kind it is either, so not much help to you.
 
Thanks for taking the trouble to measure up your chain.
It looks quite similar but do you know if it is calibrated chain?
 
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I've no idea if it is "Calibrated". It's a long time since chain was made by hand, so I would assume that all machine made chain has identical links. I often wonder if the term "calibrated" is just a wheeze to separate people from even more money.
 
The sizes are a bit odd.

They do not seem to match metric 12/13mm nor imperial 1/2 inch short link. The link length is about right for metric, but too wide and its about the right width for imperial but too short.

However its such a big chain I assume you already have a windlass (or are very, very strong) and one way to find out what you have might be to look at your existing gypsy. If the chain already matches your gypsy (and does not jamb) then the gypsy size will be embossed as part of the casting on one side, or half, of the gypsy. Normally access to gypsies is easy.

You could then look for a windlass with that size of gypsy. If you are really clever, and very lucky, you might be able to buy a new windlass and install your old matching gypsy on the new windlass (I don't know but maybe, say, Lewmar have kept dimensions the same even though they have upgraded their windlass) - but its a yacht and you are unlikely to be that lucky. Gypsies should last for ever. Horizontal windlass, that have a vertical gypsy are more forgiving of mismatch of chain size because the chain usually only engages for about 90 degrees whereas vertical windlass with horizontal gypsies usually engage for 270 degrees - and thus a good number of links.

The other option is to cut off about 1m of chain and take it with you and size it on the gypsy of the windlass you want to buy. But I would not buy a windlass without physically checking first. You could do the same with your old gypsy, take it and check it fits the new windlass.

12/13mm chain is huge, and in G3 has a working load limit of 2t (and a min breaking strength of 8t) - you must have an enormous yacht. It might not be much more expensive to buy a smaller windlass (than you would need for 12mm chain) and buy both new small windlass (smaller wiring, less drain on battery so no need for separate battery etc etc) and new 10mm (or even 8mm) chain. Though oversized windlass are better than ones that are a bit small.

Jonathan
 
SHUG said:
Thinking of installing a new windlass but I am having difficulty in establishing what the present anchor chain actually is. I have looked at Lewmar charts and Bradley chain but I can't get a good match.
Here are the average dimensions:

d, chain thickness, average….12.6mm
p, link inner length, average…36.1mm
w, link width, average………..45.7mm
L. overall link length. Average..60.4mm

The conclusion may be that its agricultural chain but I'd appreciate any help you can give.
Click to expand...

It sounds like 1/2" chain - being used on a winch I'd suggest it's already calibrated.

Mighty heavy stuff for a normal size boat - as suggested I'd recommend taking a length and matching the windlass gipsy to that.
 
charles_reed said:
It sounds like 1/2" chain - being used on a winch I'd suggest it's already calibrated.

Mighty heavy stuff for a normal size boat - as suggested I'd recommend taking a length and matching the windlass gipsy to that.
Click to expand...

That's a sizeist comment. :DMy previous boat had two anchor chains, one was 16mm, the other was 18mm.
 
The chain is used with a barrel windlass which does not have a gypsy.
So...the hope is that it is calibrated chain and it can be used with a gypsy BUT it may well be a nominal chain in which case I have some thinking to do.
Thanks for the contributions.
barrel windlass.jpg
 
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