Lengthening chain

[TiggerToo]

I'd like to add a few metres or twenty to Tigger's anchor chain (8mm, calibrated). What is the best way of joining galvanised chain so that it goes over a windlass gypsy without too many problems?

 

[pcatterall]

Well; this months PBO has an article about putting a new link in chain so I s'pose that that is also an appropiate way to extend one.

 

[TiggerToo]

Well; this months PBO has an article about putting a new link in chain so I s'pose that that is also an appropiate way to extend one.

don't take PBO: can you suggest where to get kosher chain links?

 

[Heckler]

don't take PBO: can you suggest where to get kosher chain links?

me or vyv cox
Stu

 

[Alex_Blackwood]

Here!
http://www.amazon.co.uk/Stainless-Steel-Chain-Connecting-Link/dp/B004U4WWRG

 

[srah1953]

Here!
http://www.amazon.co.uk/Stainless-Steel-Chain-Connecting-Link/dp/B004U4WWRG

Is there not some issue about joing stainless to galvanised?

 

[prv]

Here!
http://www.amazon.co.uk/Stainless-Steel-Chain-Connecting-Link/dp/B004U4WWRG

"Tmc Technology Corp"? Never heard of 'em.

I'd rather have one of Stu's links, made by Crosby and with its own load-test certificate.

As, indeed, I do.

Pete

 

[Poignard]

Here!
http://www.amazon.co.uk/Stainless-Steel-Chain-Connecting-Link/dp/B004U4WWRG

Do you think they as strong as the chain they join?

Seems counter-intuitive to me. I mean, if you split a chain link in two and then rivetted it back together, (which is effectively what you have there) would it be as strong as it was before?

 

[rob2]

If you use a stainless link, once it gets in salt water it will strip the galvanising from adjacent links which will then rust out. When I bought Mojo, the anchor was attached with a stainless shackle. The end six inches of chain was rotten and the galvanising gone from the end of the shank. The shackle was fine, though...

Rob.

 

[cliff]

Do you think they as strong as the chain they join?

Seems counter-intuitive to me. I mean, if you split a chain link in two and then rivetted it back together, (which is effectively what you have there) would it be as strong as it was before?

In one word, NO.

You have a 50% reduction in XSA hence only 50% of original full section tensile strength. The only way round this is to use high tensile materials with a tensile strength double that of the original material.

I prefer to use a welded joining link when I am joining, two or more, lengths of chain together. The welded link can be fettled and then phosphated and finally coated with galvafroid™.

 

[Poignard]

In one word, NO.

You have a 50% reduction in XSA hence only 50% of original full section tensile strength. The only way round this is to use high tensile materials with a tensile strength double that of the original material.

Just so. Those things are a complete con.

 

[Searush]

Just so. Those things are a complete con.

Well, is strength of chain critical to its use for anchoring, or is it the weight that is critical? I suspect that most of us won't use a tenth of the strength of our anchor chains - even in extremis - so that still leaves a factor of safety of 5 (ie 5 times stronger than required)

Please note, no calculations or accurate data have been used in this post. Please feel free to do that for yourselves as I can't be @rsed.

 

[Caladh]

Like Tigger I am thinking of extending my chain. Assuming we join it somehow, is it best to join it at the anchor end of the existing chain or the locker end ?

 

[DaiB]

C links

http://coxengineering.web.officelive.com/Clinks.aspx

Read this test and then make your own mind up!!

If you do get a Crosby link be prepared for a lot of work with a ball pein hammer to rivet it together.

 

[Rivers & creeks]

What about a short length of anchorplait spliced onto both lengths of chain as a joining piece?

 

[V1701]

Like Tigger I am thinking of extending my chain. Assuming we join it somehow, is it best to join it at the anchor end of the existing chain or the locker end ?

I can't see any circumstance where there'd be more strain at the anchor end than the boat end whereas there could well be more at the boat end, so joining at the anchor end would be the way to go I'd have thought...

 

[Poignard]

I can't see any circumstance where there'd be more strain at the anchor end than the boat end whereas there could well be more at the boat end, so joining at the anchor end would be the way to go I'd have thought...

+1. That way if it breaks you have something left to attach your spare anchor to. Also the chain will act as a drag and give you a little more 'What now, skipper?' time as you make your way across the anchorage.

 

[sailorman]

What about a short length of anchorplait spliced onto both lengths of chain as a joining piece?

lateral thinking Eh.
it wont run around his calibrated gypsy

 

[wazza]

This is what we DONE 2 seasons ago! Went to a welder with both lengths and he cut the last link and welded it together.. at an angle so the was more surface area to 'stick' together..
It has lasted 2 seasons with constant anchoring..

 

[vyv_cox]

In one word, NO.

You have a 50% reduction in XSA hence only 50% of original full section tensile strength. The only way round this is to use high tensile materials with a tensile strength double that of the original material.

I prefer to use a welded joining link when I am joining, two or more, lengths of chain together. The welded link can be fettled and then phosphated and finally coated with galvafroid™.

The good ones are high tensile. Crosby, Seafit (sold by West Marine) and possibly ACCO, have a UTS around 90% of chain strength. All of these are manufactured for hoisting duties for which there are arduous standards, unlike yachting. Stainless steel ones have a UTS of 50 - 60 % and some of the ones sold in chandleries far worse. See my website for detailed info.

You would need a high confidence level in the welder butt-welding a link so that it would pass through a windlass.