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Old 11-09-2012, 06:22   #16
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Re: Which Anchor Chain

Go cheap and g30/40 you loose the strength as soon as the chain is redipped and would your deck hardware be ripped out before the chain snapped?
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Old 11-09-2012, 11:23   #17
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Re: Which Anchor Chain

The use of a snubber is almost mandatory with all chain to keep from doing damage to chain, shackles, bow roller,windlass. I must take exception to something capta said(no offense ment) about having a great big loop in the chain when using a snubber. A nylon snubber(just plain rope) is or should be sized to your boat so that you get plenty of stretch out of it. A 30 foot nylon rope can safely be streched about another 10 feet. When you attach the snubber(I just use a rolling hitch) let out the chain until the nylon takes the strain and then let just enough extra chain to allow for the 10 foot or so stretch of the nylon. The reason IMO that you dont want a huge loop of chain is that if or when the nylon chafes through, or breaks, or the cleat gets ripped out of the deck, your boat doesnt have enough room(slack) to build up momentum and then really stress the chain when it jerks up tight. The chain coming up tight when the line is stretched nearly to its limit is not a problem since the snubber will have allready taken the snap out of it. The thread on this forum titled BOUNTY BAY should be looked at to see a situation where chain could easily break. My first thought when I watched the vidio was that they must have used a snubber or the chain would have allready broken. __My 2 cents worth.____Grant.
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Old 11-09-2012, 11:48   #18
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Re: Which Anchor Chain

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Originally Posted by Andrew Troup View Post
I think the recent fashion for using smaller chain of higher strength steels is likely to end badly when an increasing number of these rodes have seen a few regalv cycles, a lot of wear, and many many load reversals.

Relying on this combination, it seems to me, is a bit like using a racehorse for a job which (when things get ugly) really requires a draught horse.

I wouldn't be surprised to see a rebound in due course, to something more akin to former proportions and material strengths.
IMHO, there are some good arguments for G70 chain of a smaller size. But it can be expensive, since AFAIK you can't regalvanize G70 chain even once. If you can stand the weight in our bow -- and many can't -- I would go with G40 and a robust size.

I have 330 feet of 1/2" G40, weighing the better part of half a ton, but my boat has plenty of buoyancy in the bow and doesn't seem to mind it. YMMV.

There is an excellent discussion of the various tradeoffs on the old Rocna site -- Chain (Rocna Knowledge Base)

I respectfully disagree with Capta about the strength of chain not mattering. The anchoring system as a whole is only as strong as its weakest link. Of course a good snubber is essential to avoid the snatch loads which will break any chain, but the whole system still needs to have minimum strength appropriate to the loads likely to be encountered without snatch loads. I think the ground tackle is something every sailor needs to have total confidence in - because its failure can be so disastrous. So I would never compromise on strength of the chain, personally.
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Old 11-09-2012, 11:50   #19
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Re: Which Anchor Chain

Quote:
Originally Posted by gjordan View Post
The use of a snubber is almost mandatory with all chain to keep from doing damage to chain, shackles, bow roller,windlass. I must take exception to something capta said(no offense ment) about having a great big loop in the chain when using a snubber. A nylon snubber(just plain rope) is or should be sized to your boat so that you get plenty of stretch out of it. A 30 foot nylon rope can safely be streched about another 10 feet. When you attach the snubber(I just use a rolling hitch) let out the chain until the nylon takes the strain and then let just enough extra chain to allow for the 10 foot or so stretch of the nylon. The reason IMO that you dont want a huge loop of chain is that if or when the nylon chafes through, or breaks, or the cleat gets ripped out of the deck, your boat doesnt have enough room(slack) to build up momentum and then really stress the chain when it jerks up tight. The chain coming up tight when the line is stretched nearly to its limit is not a problem since the snubber will have allready taken the snap out of it. The thread on this forum titled BOUNTY BAY should be looked at to see a situation where chain could easily break. My first thought when I watched the vidio was that they must have used a snubber or the chain would have allready broken. __My 2 cents worth.____Grant.
+1

I agree with this analysis entirely.
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Old 12-09-2012, 07:27   #20
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Re: Which Anchor Chain

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Originally Posted by Dockhead View Post
IMHO, there are some good arguments for G70 chain of a smaller size. But it can be expensive, since AFAIK you can't regalvanize G70 chain even once.........
Got any evidence about not be benig able to regalvanize G70 chain? Here's some info from Facts About Anchor Chain Strength and Grades on the Morgan Cloud site.
Quote:
All three chain grades can be supplied galvanized. With grades 30 and 43 this process has no deleterious effect on strength. However, because grade 70 is already heat treated, the heat in the galvanizing process causes it to lose about 10% of its strength, both WLL and MBL.
By the way, contrary to a widely held opinion, re-galvanizing does not reduce the strength of any of the three grades—no, not even grade 70—because the effect of heating in the galvanizing process is not cumulative. But this is only true provided said re-galvanizing is done properly.
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Old 12-09-2012, 12:42   #21
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Re: Which Anchor Chain

If some shop botches the re-galvanizing process it does not turn your G70 into wet noodles. It turns it into un-heat-treated 1022 carbon steel.

Also known as G43.....
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Old 12-09-2012, 13:59   #22
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Re: Which Anchor Chain

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Originally Posted by Paul L View Post
Got any evidence about not be benig able to regalvanize G70 chain? Here's some info from Facts About Anchor Chain Strength and Grades on the Morgan Cloud site.
Your information is more detailed and precise than what I wrote.

Naturally you can regalvanize anything. It's a different question, however, what you will get in the end. It is often said that regalvanizing G70 chain is a bad idea, because it can easily lose even much more than the 10% figure stated if the temperature is wrong (because the strength of G70 comes from heat treatment). Even the Morgan's Cloud site you cited says you shouldn't do it. I should have said it that way, but was too lazy at the time -- thank you for calling me on it.
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Old 12-09-2012, 15:19   #23
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Re: Which Anchor Chain

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Originally Posted by Exmoor View Post
I ned to buy anchor 5/16" chain for my new Maxwell windless

what is the best type of chain to use ie; g4, g3, BBB, HiTest etc

Dont Have much idea about chain so any help would be appricated

Also the names of good suppliers would be appriciated.

Thanks

Chris
For your boat, 42ft/14" beam, ABYC indicates 1800lb working load, 3600 storm load (42kt winds & waves).
Hurricane Survival

5/16 G4 has a Safe working load of 2925lb.

If you are going to be inland sailing or coastal cruising that should suffice. If you are intending to go offshore then you need to reconsider the whole setup. If you are going to sail in high latitudes then even the storm loads listed above need to be increased.

ABYC loads are pretty conservative and you probably could get away with the 5/16-G4 offshore but no garuntees.

If you went with a 5/16-G7 you will be OK if you can get shackles that meet the 3600. I do not have the Crosby values handy. The downside to G7 is regalvanizing when the chain gets worn is problematical. The regalvanizing process may heat the chain up enough to remove the temper that gives the chain it's extra strength compared to G4. The only way to know is to nip of a couple of feet of chain after regalvanizing and have it tested to destruction at a testing facility.

What is the possibility of getting a larger replacement gypsy for the windlass?
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