how do i measure chain

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blackbess2

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re chain size ie 6mm 8mm and so for anchor how do i measure chain to determine what size it is ??
 
I believe it is the diameter of the rod used for the links. So measure the thickness of one side of a link - ie it's height if a single link were laid flat.

Cor, that's hard to explain without a picture! :confused:
 
re chain size ie 6mm 8mm and so for anchor how do i measure chain to determine what size it is ??
Depending on what you're needing to do, you may need to know more than just the size (which is correctly said above to be the OD of the rod). Anchor chain is short link, should be calibrated if for use with a windlass, and there are a number of different standards which vary the pitch and breadth slightly from one to the other.
 
The rod size comments are spot on, but if you are using a windlass with your chain, the dimensions of the chain are more complicated: the chain proportions could comply with one of three or more standards relating to the internal measurements of each link, so 10mm chain could be anything from about 28mm to 32mm long, which has huge implications for the windlass...
 
Revive an old post as i was searching.So what size would be a good choice for a 10t yacht which would give the most flexibility with a modern electric windlass.
 
Revive an old post as i was searching.So what size would be a good choice for a 10t yacht which would give the most flexibility with a modern electric windlass.

With a boat of that displacement you are in the region between 8 mm and 10 mm if considering Grade 30 chain. However, most Chinese production nowadays is well into Grade 40 strength, for which 8 mm should be sufficient. Buy from a known source, e.g. many chandleries are supplied by Bainbridge, or go direct to William Hackett or Bradney, all buy in from China and can be trusted. If you go to 10 mm the added weight will be considerable, maybe 80 kg difference for a typical rode length.

Main thing of course is that the chain bought must match the gypsy. All modern European windlasses will be to DIN 766 for 8 mm chain but be careful with 10 mm, in which there is a 2 mm difference in link length between the DIN 766 and ISO 4565 standards.

Lots of info under 'anchoring' on my website.
 
Revive an old post as i was searching.So what size would be a good choice for a 10t yacht which would give the most flexibility with a modern electric windlass.

That depends entirely on the windlass gypsy spec. It will be designed for a specific size of chain & any other size will not fit like it should & will ride up, clog or slip every few links. If you decide you want a different sized chain to the current gypsy calibration, you should be able to change the gypsy to suit. As stated earlier in the thread, your chain needs to be calibrated (ie tested to make sure all links are within the tolerances the gypsy will have been designed for). Cheap chain is often lengths that have failed calibration & which are only suitable for manual deployment & recovery.
 
Link length has to match the gipsy on the windlass. To determine that, takes a bit more headscratching. You will need "calibrated" chain with the matching bar diameter. Really, the only way to find that, beyond guessing, is to find a short length of chain that fits the gipsy, then measure the bar. If the chain doesn't fit properly, don't get your fingers in the way when winching !
 
Main thing of course is that the chain bought must match the gypsy. All modern European windlasses will be to DIN 766 for 8 mm chain but be careful with 10 mm, in which there is a 2 mm difference in link length between the DIN 766 and ISO 4565 standards.

Just bought 50m of calibrated 10mm chain in Croatia for a Quick windlass. I took a few links from the existing chain to the chandlers at the marina and he measured the inside link length as 30mm (50mm external length including the two sections of 10mm chain itself). He measured the chain he stocks as 28mm inside link and said that the 30mm was difficult to obtain in Croatia. However, after asking around I managed to find the 50m of 30mm link I wanted at a reputable chandlers in Split. Transporting 50m of chain by car from chandlers to boat 25 miles away with only SWMBO was an interesting experience but where there's a will etc.

Richard
 
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