Anchor Chain Choices

[noelex 77]

Originally Posted by fxykty

Functionally in the case of chain dimensions and windlass gypsys 3/8” and 10mm are equivalent.

This is not true of all, or even most windlass gypsies.

You need to be careful with this common size of chain. There are two different sizes of metric 10mm chain, and 3/8 is different again. While the wire size is the same or similar, the other dimensions such as the length and width of each link is substantially different.

There are some gypsies that can accommodate these multiple sizes, but many are very specific.

[GordMay]

Originally Posted by fxykty

... We had 65m of 1/2” / 12/13mm G40 chain. We downsized to 90m of 3/8” / 10mm G80 chain...
... We didn’t even consider 10mm G40 due to the lower working load (about 1600kg, with break at 6500 kg), compare to G70 working load 2200kg and break at 11000kg. The 1/2” G40 we replaced was about 1800kg working and 8900kg breaking.

Was your new chain G80 alloy hoisting chain, or G70 heat treated transport chain?

[Dockhead]

Originally Posted by s/v Jedi

I can’t follow you. Option #3 which I recommend is 10mm G40. 10mm is bigger diameter than 3/8” and your post seems that you think option #3 is G70 instead of G40?
Anyway, I’m pretty sure everything I wrote is correct

Yes, you are right -- I confused my own list of choices


OK, now your post makes sense.

[fxykty]

Originally Posted by GordMay

Was your new chain G80 alloy hoisting chain, or G70 heat treated transport chain?

G80 hoisting chain. Paint was mechanically stripped and galvanising applied by Armorgalv in Newcastle Australia.

[fxykty]

Originally Posted by noelex 77

This is not true of all, or even most windlass gypsies.



You need to be careful with this common size of chain. There are two different sizes of metric 10mm chain, and 3/8 is different again. While the wire size is the same or similar, the other dimensions such as the length and width of each link is substantially different.



There are some gypsies that can accommodate these multiple sizes, but many are very specific.

Chain is either DIN766 or ISO4565. DIN chain links are shorter and wider, while ISO chain links are longer and skinnier. Good windlass brands offer gypsies for both standards - when buying chain make sure you buy the given size in the DIN/ISO standard that matches the gypsy you have or will get.

Within each standard, 1/2” imperial is equivalent to both 12mm and 13mm chain. For our Lofran’s Falkon windlass the original gypsy shows markings for 1/2”, 12mm and 13mm diameters.

3/8” and 10mm are similarly equivalent within each standard. Our new gypsy shows markings for 3/8” and 10mm diameters.

[Dockhead]

In the event I went with 100m of 12mm G40 chain, just like my previous chain.


The chain is made in France by Chaineries Limousines. The cost was reasonable (about €14.35 per meter), and the chain is supposed to be good quality, with some allegedly unique galvanizing process.


I bought it from a French retailer, "Sea Tech & Fun", whom I had never heard of, but they were remarkably efficient, answering tech support questions by telephone within minutes, and shipping the chain out the same day I ordered it. We'll see what it looks like when it gets here.


One heads up to CFers -- Many of us have had trouble finding good shackles without ears which catch in the bow roller. I have been using a high resistance stainless allen bolt shackle from Wichard which I didn't like much.


Well, Chainerie Limousines make a cool looking galvanized shackle like this:





The 12mm version of it has breaking force of fully 16 tonnes, more than 1.5x the breaking force of the chain (9.2 tonnes).


I think that the shackle, which is potentially subject to different odd loads, should be about this much stronger than the chain.


This whole system however is overkill I think, and I am paying for that in weight (330kg or a third of a metric tonne). I could have lost 100kg out of that by changing the gypsy and going down to 10mm but in the event conservatism overcame me.

[Jim Cate]

DH, how does that shackle work... that is, how does the pin come out? Not clear from the pic!

And BTW, I agree with your chain choice. Worked before, will work again with no learning curve bumped along by a failure somewhere.

JIm

[Dockhead]

Originally Posted by Jim Cate

DH, how does that shackle work... that is, how does the pin come out? Not clear from the pic!

And BTW, I agree with your chain choice. Worked before, will work again with no learning curve bumped along by a failure somewhere.

JIm

It works basically like my previous Wichard one did -- allen key and Locktite.


Difference is this one is stronger and galvanized instead of stainless. We'll see if it's any good; I'll report here after trying it.

[BigAl.NZ]

Whats are these ratings I see of G40, G43 etc?

I am on the market for new chain. Some say the Italian stuff is ok, some say Australian.

Hope this isnt considered a hijack but it seems pointless to start a new thread. Boat is a mono hull 12ton currently with 90m of 5/16th but will change to 8mm.

Thoughts and brand reccomendations?

[fxykty]

Originally Posted by BigAl.NZ

Whats are these ratings I see of G40, G43 etc?



I am on the market for new chain. Some say the Italian stuff is ok, some say Australian.



Hope this isnt considered a hijack but it seems pointless to start a new thread. Boat is a mono hull 12ton currently with 90m of 5/16th but will change to 8mm.



Thoughts and brand reccomendations?

If you’re in NZ (Auckland according to your profile) then go in and talk to Chains, Ropes and Anchors https://chainsropesandanchors.co.nz/ in the Wairau Valley. For higher grades (G40 and G70) they stock Italian Maggi and MFI Chains.

If you want a bit more strength than G40 but don’t want to deal with potentially brittle G70 then check out Ozzie Marine http://www.ozzimarine.com.au/ in Queensland. They sell an Australian made G43 chain.

[BigAl.NZ]

What does G40, G43 and G70 mean? What are the pros and cons?

[fxykty]

Originally Posted by BigAl.NZ

What does G40, G43 and G70 mean? What are the pros and cons?

https://chainsropesandanchors.co.nz/...are-they-about

Not quite the same controversy as anchor discussion, so I’ll take a chance with some generalisations:

The pros of higher grade chain is more strength for a given size, which generally means you can go down a size (say from 10mm to 8mm) and reduce the weight of chain for a given length while maintaining the strength your anchoring system needs. Smaller links will also slide over themselves better, suiting a smaller chain locker.

But less weight in chain may mean less chain catenary and more load on your anchor. Your snubber becomes more important and you may need to use longer scopes - it’s a little like what happens when you switch from an all chain rode to one that is all rope.

Also, G70 chain is more brittle and cannot be regalvinised. G40 chain is less brittle but shouldn’t be regalvinised more than once. G30 can be regalvinised however many times you want. But it’s links will be most prone to stretching over time, eventually wearing and then not fitting your gypsy.

[Dockhead]

Originally Posted by fxykty

https://chainsropesandanchors.co.nz/...are-they-about

Not quite the same controversy as anchor discussion, so I’ll take a chance with some generalisations:

The pros of higher grade chain is more strength for a given size, which generally means you can go down a size (say from 10mm to 8mm) and reduce the weight of chain for a given length while maintaining the strength your anchoring system needs. Smaller links will also slide over themselves better, suiting a smaller chain locker.

But less weight in chain may mean less chain catenary and more load on your anchor. Your snubber becomes more important and you may need to use longer scopes - it’s a little like what happens when you switch from an all chain rode to one that is all rope.

Also, G70 chain is more brittle and cannot be regalvinised. G40 chain is less brittle but shouldn’t be regalvinised more than once. G30 can be regalvinised however many times you want. But it’s links will be most prone to stretching over time, eventually wearing and then not fitting your gypsy.

I used to think that G70 is more brittle, as you stated, but I have been told by knowledgeable people that this is not so. Don't know about regalvanizing.

It's true what you say about the catenary, however, and furthermore, thinner chain, no matter how strong it is, will degrade faster from corrosion -- there is less "meat" on it. That's why I ended up going with 12mm again and not downsizing to 10mm, although 10mm even G40 would probably be strong enough for my boat.

Although it's 330kg of chain, I don't notice any difference in how she sits on her lines, and it only fills half of the divided chain locker less than half way up. The ride in deep water with 330kg of chain out is PLUSH. I almost never use a snubber.