Anchor Chain

[rnjpinz]

Here we go again. It is the 11th hour and my new Lighthouse 1501 Windlass is being assembled and ready to ship within the next week. . One of the owners of Lighthouse tells me in a telephone conversation that he feels my choice for 3/8 HT is unnecessary. He says 5/16 is good. The boat is a 40 Caliber LRC. Displacement is 23,000 Others have told me 3/8 will let me sleep better. Need convincing.

Bob
T

[beetle]

Originally Posted by rnjpinz

Here we go again. It is the 11th hour and my new Lighthouse 1501 Windlass is being assembled and ready to ship within the next week. . One of the owners of Lighthouse tells me in a telephone conversation that he feels my choice for 3/8 HT is unnecessary. He says 5/16 is good. The boat is a 40 Caliber LRC. Displacement is 23,000 Others have told me 3/8 will let me sleep better. Need convincing.

Bob
T

How much chain are you planning to carry, how much of a weight penalty are you willing to pay, and where are you planning to be anchoring?

I'm using 5/16" G40 chain on my 45 foot 21,000 lb. sailboat here in San Francisco, and have had no problem staying put between here and Cabo San Lucas. That said, there's always been good holding on the bottom and I go with 7:1 scope despite the fact that I have chain on the bottom.

My guess is that 3/8" HT (G40) chain is a bit over the top. Nothing wrong with the over the top for anchoring, mind you, except for initial cost and weight on the bow.

- rob

[roverhi]

We sure slept soundly on our 20,000 plus Westsail with 3/8" high tensile chain rode. Never dragged in over a year even in a Tropical Depression with 50mph plus winds. Most of the time, the boat never straightened out the chain. Could have just dropped the chain and dispensed with the anchor. People say the catenary of the heavy chain isn't that important but I'd beg to differ. Even during the storms, the chain didn't go straight.

5/16" chain is strong enough but I like the weight of 3/8".

[craigsmith]

Originally Posted by roverhi

Could have just dropped the chain and dispensed with the anchor.

Nonsense. Try it next time. And if a storm's not straightening your chain, it's no storm.

Originally Posted by rnjpinz

Here we go again. It is the 11th hour and my new Lighthouse 1501 Windlass is being assembled and ready to ship within the next week. . One of the owners of Lighthouse tells me in a telephone conversation that he feels my choice for 3/8 HT is unnecessary. He says 5/16 is good. The boat is a 40 Caliber LRC. Displacement is 23,000 Others have told me 3/8 will let me sleep better. Need convincing.
T

Don't say HT if you mean high test (G40), not high tensile (G70). HT means the latter.

Your anchor - to the great surprise of many, it would seem - is what holds your boat. It is therefore sensible to match the chain to the anchor, as the choice of the latter in consideration of the boat's size properly informs the required rode strength. Because you've not stated what size and type anchor you have, it's a rather futile exercise discussing required chain.

Chain (Rocna Knowledge Base)

[cliffdykes]

Craig,
Got out of the wrong side of the bed this morning?

Cheers
Cliff

[rnjpinz]

My primary anchor is a Manson Supreme 45. And the chain I am thinking of buying would be 3/8 G40.
Bob

[craigsmith]

Then I agree with the Lighthouse man, even if you had a genuine Rocna instead of the knock-off, 3/8" is unnecessary - a lot heavier and more expensive for no benefit - 5/16" G40 is the way to go.

[gcaptain]

I agree that 5/16" will hold you, so breaking strength isn't really the issue here weight is, you would want a heavier anchor chain to hold centenary in the line during a storm but letting out more scope accomplishes the same thing.

The time a heavier chain will help is in a crowded anchorage where you might not be able to get the scope you need... but, that being said, visiting a crowded anchorage in bad weather is not the best idea anyway so, I'd go with the 5/16.

[GordMay]

See the charts:

➥ WLL for Anchor Rodes - ABYC Section H-40, Table 2 Cruisers & Sailing Photo Gallery

➥ Design Loads for Deck Hardware - ABYC Section H-40, table 1 Cruisers & Sailing Photo Gallery

Your 40 ft boat would present about 2400# of loading on a storm anchor; requiring at least 3/8" Proof Coil, or 1/4" High Test chain.
Accordingly, 5/16" G40 would do very nicely.

[cfarrar]

My 42 ft boat is a smidge heavier than yours, with a 55# Rocna and 5/16" G40 chain. This set up works great, and I do not plan to change it.

[estarzinger]

Originally Posted by rnjpinz

He says 5/16 is good. . . . Others have told me 3/8 will let me sleep better.

In the other thread you indicated your cruising ground would be the caribbean. The anchorages there are not terribly deep, and not terribly prone to sharp coral, but can be crowded. I don't know the lighthouse very well, but if it's gypsy is a 'chain and rope' design (eg can pull either), I would suggest say 100' of 3/8" g4 with 200' of nylon beyond that. That will give you 'all chain' in most anchorages, a nice heavy chain to allow you to fit into tight anchorages, without excessive weight.

On our first boat (37'er), we had 75' of chain (plus rope) for the carrib and then added another 75' (which had been stowed in the bilge) when we got to the pacific for the deeper more coral struned anchorages there.

One question to ask about the smaller g4 chain is whether you plan to regalvanize it or to throw it out when it gets rusty (in perhaps 5 years). If you plan to regalvanize, be aware that will affect its heat treatment and thus reduce its strength and I would be happier with the extra margin of the 3/8. If you plan to always buy new chain and not regalvanize then this is obviously not a concern, and the 5/16 is string enough, and then the only question really is about the ability to short scope and sit quietly in tight anchorages.

If your simple question is what will let you sleep better, heavier chain will - it will keep the boat quieter, damp the boat's tendency to sail back and forth. But if the question is 'how light can I get my bow' - then 75' of new (non-regalvanized) 5/16 with rope is probably the answer. And then there are all sorts of compromises between those two positions.

Don't stress too much about this, just decide which way you want to lean (good sleeping or light weight) and go for it. Any of these compromises will work.

[craigsmith]

Evans your dichotomy between good sleeping and light weight is utterly false. 5/16" is not even close to marginal, it is perfectly conservative. It is only when going with a short chain leader that some extra weight might be on the "why not" list; if all chain is desired then lighter is better. Additionally, re-galvanizing will NOT affect G40 chain. At all.

[estarzinger]

Originally Posted by craigsmith

Evans your dichotomy between good sleeping and light weight is utterly false.

As to a dichotomy about light weight and good sleep - I can tell you that heavy chain does help me sleep well - how the hell can you even think of telling me otherwise. Perhaps its 'only psychological' (I doubt it) but its still better sleep.

5/16" is not even close to marginal, it is perfectly conservative. It is only when going with a short chain leader that some extra weight might be on the "why not" list; if all chain is desired then lighter is better.

If you actually read my post you would note that I was in fact suggesting a mixed rode and not an all chain rode.

Additionally, re-galvanizing will NOT affect G40 chain. At all.

Well, as you know, GMac disagrees with you on the regalvanizing: "'I've had people argue against all of this but I've seen big strength loses on newly regalvanised chains with my own eyes on more than one occasion and believe the people who should actually know. We've also had the odd "I've regalvanised my chain 5 times now and it's perfectly fine". To that I'd say how the bloody hell would you know unless you've tested it."

as apparently does "Gary Lind, the Quality Assurance Manager/ISO 9001 Management Rep. from Peerless Chain Co (ACCO's new owner). This is his response to my question on chain degradation due to re-galvanizing (sorry about the caps):

WE CAN RE-GALVANIZE CHAIN. THE CHAIN MAY BE STRIPPED AND CLEANED PRIOR TO GALVANIZING, BUT WILL DEPEND ON THE EXISTING CONDITION OF THE CHAIN AND NUMBER OF TIMES IT HAS BEEN GALVANIZED. RE-GALVANIZING “USED" CHAIN WITHOUT KNOWING THE MATERIAL TYPE, NUMBER OF PRIOR GALVANIZING OPERATIONS AND SERVICE CONDITIONS THE CHAIN HAS BEEN SUBJECTED TO, CAN BE AN ISSUE. . . . .

OUR TYPICAL INTERNAL ALLOWANCE FOR GALVANIZING LOW CARBON NON-HEAT TREATED CHAIN IS NO MORE THAN TWICE, WITH A REQUIREMENT FOR BEND AND TENSILE TESTING AFTER A RE-GALVANIZING BASED ON THE NOTED POSSIBLE PERFORMANCE ISSUES. FLASH PICKING AND SHOT BLASTING IS ALSO USED FOR GALVANIZING ALLOY STEELS TO MINIMIZE EXPOSURES TO HYDROGEN. "

anchoring threads . . .

[craigsmith]

Grant MacDuff is not a metals engineer and by his own admission is no expert in the field. The somewhat vague and abstract article you are quoting from is here for those interested in the full story. In any case when Grant talks against re-galvanizing, 1) he is a chain salesman and benefits from "his punters" buying new chain (I suppose I should be claiming you can't re-galvanize anchors...), and 2) he is talking about high tensile grades (and even then frankly he is off the mark on a lot of points). G40 is not even heat treated (mostly).

Gary Lind's comments sound more rational. What is your point? They concede it is fine, "twice", and consider their interest in the purchase of new chain vs re-galvanizing... Hydrogen embrittlement is not an issue at all with G40, that's just Chicken Little talk, and you will have trouble finding any expert consensus on whether it's even a real problem with G70.

[roverhi]

Craigey Poo, a bit grumpy this morning!!! Most of the time we anchored 24/7/365 for nearly two years, the 3/8" chain never pulled on the anchor. The chain sat in a jumble on the bottom. The 45# CQR was really superfluous. I'd never drop just chain but for the most part would have done just fine without an anchor. In the storm I mentioned, the chain did straighten out but didn't go bar tight. There was still catenary to minimize the shock of the wind loads. We were in well sheltered water with minimal wave action. If you do get in a situation where there is no longer a catenary, you will be putting tremendous shock loads on the boat, chain, and anchor. You'd better have a snubber or hope someone has heard your prayers.

Personally think it's not wind loading that's a problem when anchored but wave action that's the challenge. Hung on a mooring for nearly year in Norfolk. Went through two remnants of hurricanes that passed through. One was no biggy as the winds never came from the direction of open water. The other one sent 40 knot winds into the mooring field over about 10 miles of open water. Waves got up to a point where bow was going under green water regularly. It was not the most restful night I've spent. Fortunately, the chafing gear on one of the mooring lines didn't wear through

People claim that the weight of the chain isn't a factor in anchoring, I disagree whole heartedly. The heavier chain makes the work of the anchor a whole lot easier and puts less stress on the boat. Having said that, the weight of the chain in the locker is a factor. If the boat still handles acceptably with the weight of heavier chain, I'd definitely sleep better with it. Never once woke up in the middle of the night with a concern about our anchor or dragging.