Chain type and quality

manyboats said:

Noelex,
Going to all the trouble to employ a 45' snubber I'd be inclined to just use a combination rode w only about 45' of chain. A 35 to 40' trawler w 20' of 1/2" chain and 25' of 3/8" chain should have lots of centenary protection and plenty of shock absorbing nylon line. Of course this is academic as few have a good enough winch to accommodate such a rode. I tend to think in ideal terms and then go from there. And I think the above chain arrangement would have the best centenary advantage if the heavier chain was positioned closer to the boat. I believe we had a discussion about that 5 or so years ago.

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A combination rode has a lot advantages as you mention. The big problem is chafe. Rope is not as safe as chain.

Many boats insist on an all chain rode for this reason. If a snubber is broken by chafe the chain is still present as a back up. If chafe is unlikely to be a problem a combination rode saves a lot of weight.

All chain is also easier to manage with an electric/hydraulic anchor winch, but the lighter weight of a combination rode is a big help if retrieving by hand.

Heavy chain close to the anchor does help catenary, but most of the effect is lost when it needed, in strong wind. The thicker chain also slightly inhibits the anchors diving. A Thin SS wire or a Dyneema strop has been suggested as superior, in some circumstances, for this reason.

FF said:

Option 2 is to use a heavy weight secured to the chain or slid on with a rode rider that will assist the catenary when in the wind lulls.

The weight will sink to the bottom so there is some movement before the chain goes rod tight.

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My boat came with a virginal looking Anchor Buddy, a catenary weight with quite some design to it, made in NZ. Never actually used it, must give it a go, but with the Super Sarca and all chain....

Big thumbs up to post 31 and 32.

I know I said this would, specially for the season of goodwill, be a non contentious thread.

But, say, a 20lb sentinel/anchor buddy is equivalent to 20' of 5/16th chain (and obviously less chain if the chain is heavier duty). Really deploying an extra 20' of chain is neither here nor there, or adding a 20lb sentinel is neither here nor there. To make much difference to the rode angle you are going to need quite a large sentinel and if possible you would be better with more chain in the first place.

If a reason to deploy the sentinel is because you have restricted space then your second anchor (which in my book should be the same weight (if its steel) as the primary) can replace the sentinel (and obviously have a role as a standby/replacement anchor). You can deploy 'down' the rode or simply hang off the bow, or stern if it will not tangle in the prop or rudder, such that it simply scrapes along the seabed as a sort of friction break - it an old Navy trick.

The joy of a weight is the ease that a good deal of weight can be deployed .

Scuba belt weights at 10 lbs each 5 or 6 can easily be added.

The weight if allowed to slide along the chain , not just dropped underfoot, creates a huge lever that must be raised almost to the surface before the chain is BAR tight .

This softens the ride considerably .

Remember too, more weight can easily be added as sliding the rider back aboard does not disturb the anchor set.

I find it interesting that threads like this, focussed on chain, evoke little response (with no disrespect to those who have contributed). This suggests to me that most people are satisfied and that chain and some other components in the rode is/are not the source of many significant issues.

Unlike anchors, where a thread will engender fierce debate (are there are other topics with the same propensity for debate?) it does not appear that we want a 'better' chain. We do want, if it can be developed, a better anchor (i'm not suggesting thread drift - its simply an example) - but we all seem happy with what, in terms of chain, is currently available - or do not think chain can be improved.

There is no fierce debate over G30 and G43. There is no mention of G70. Galvanising, as is, is accepted. Chain marking and certification is not a significant discussion point. There is no significant differences between suppliers (presumably its about availability, cost and which retailer one likes),

Djbangi said:

I find it interesting that threads like this, focused on chain, evoke little response (with no disrespect to those who have contributed). This suggests to me that most people are satisfied and that chain and some other components in the rode is/are not the source of many significant issues.

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I suspect "out of sight out of mind". Essentially, rode is is either inside a closed locker, or underwater, save in either case for a small visible section. The article has me, and maybe others, thinking chain (condition, adequacy, attachments, etc).

In terms of adequacy - there are very few reports of new(ish) brand name chain actually failing and even old, some of un-known origin, chain, that has been re-galvanised, is not reported as failing. Historically most people used BBB or G30 and many still do thus the conclusion might be that G30 is perfectly adequate (and G40 or G43 - might be overkill). - This is on the basis the G30 is of a correct size for the vessel and the G40/43 is that same size (once you down size G43 because its (stronger) then there must be a question mark as you can downsize 'too' much).

As reports of G30 chain failing are few and far between one must also conclude the safety margins are quite high (and there is no need to sped that extra money on G43).

Failure, of chain, does occur but this appears to be chain of unknown (or questionable) origin. But some reports are so unreliable as to be useless (and commonly point a finger in a blanket like manner at 'China' - which is too sweeping).

Most failures reported are the components, shackles, swivels - and some, or even many, of these appear to be owner error (wrong choice or inadequately attached).

The only 'complaint' of chain appears to be galvanising, or wear of same (and many then simply regalvanise).

But interestingly though galvanising wear is a feature that people can comment on no-one comments on any subsequent chain wear, i.e. wear of the underlying raw chain (once the galvanising has gone), and anyone living on their vessel at anchor will suffer wear, initially of the galvanising, then the chain. For G43 this might not be an issue if the chain was of the recommended size but for those that downsized when they moved to G43 and those that downsized and now use G70 this is a real (and unreported) issue - as the raw steel is not very abrasion resistant.

Most wear will not be at the anchor, or near the anchor, as the chain near the anchor does not move very much. Wear will be that bit of the chain commonly sweeping the seabed in a huge arc (say that bit from 30'-60' from the anchor) - which most of us never see, its either on the seabed, or buried inside the chain locker - which is the point Bruce made. Corrosion of this worn chain is not an issue (it might be a warning sign normally) as the frequency of usage (for liveaboards) means the chain never visually degrades (as rust is worn off quickly or never has time to develop).

Possibly this has never been an issue historically as G30 has that large safety factor, some have gone to G43 which increases that safety factor and it might only be an issue for those that live on their vessel, downsized to G43 and G70 and this downsizing seems to be a recent phenomena (so little owner comment).

Like single vs twin , the chain folks have a point of view , and the combined rode folks have a very different point of view.

Chain in coral is great ,for me thats about it.

Nylon is easier to handle and usually doesnt stink below.

Happily the nylon GOD does not require me to kill all the chain GOD worshiping folks , so there is less comment from each community.