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Old 10-03-2010, 17:18   #1
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Anchor Chain - 1/4" HT vs 5/16" HT for 27' Cruising Mono

I am trying to design the best anchoring system for my needs based on all the excellent information on these threads.

I have a 27' cruising sailboat (similar to an Albin Vega 27) that I intend to cruise full time in the South Pacific in the next year and am trying to understand the best and most balanced system: I don't want to overload the bow with weight, but understand the need for as much chain as possible when anchoring in coral bottoms and for general anchoring best practice.

Looking at 1st Chain Supply I see that the weight of 150' 1/4" G40-HT is the same as 100' of 5/16" G-40 HT. I see that the WLL is significantly greater on the 5/16"

Which would you prefer and why? How much weight is tolerable in the bow of a 27' cruising sailboat? To me the 1/4" chain just did not feel all that confidence-inspiring in hand but one consideration is that this will be with no windlass so I don't want to be unrealistic.

I have been pulling up 50' of 3/8" G40 and a 22lb Delta by hand for several years in the channel islands, so am hoping that 100' of 5/16" of 150' of 1/4" will be doable w/o a windlass.

This will be on a Manson Supreme 25# with the CM Brand 3/8" red-pin shackle which comes recommended on these threads....so I guess if I do go the 1/4" HT route I will need to get an oversized end-link, which does not seem too difficult, but is a factor to consider I suppose.

Thanks for any advice!
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Old 10-03-2010, 17:24   #2
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I would think the 1/4 is strong enough. For weighing anchor by hand, it's not just the chain, it's the water depth. As for weight in the bow: none is the best. So the less the better. If you are the anchor-and-forget type then you'll want a long length in Tahiti since it will all be lying on the coral bottom. If you tend to your anchor as conditions change you can get by with far less chain lying on the bottom: saving weight and money and galvanizing and the coral and anchoring room.
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Old 10-03-2010, 17:34   #3
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Thanks daddle -- great info to consider. I agree the depth is a major factor and that the more chain the better...

Your comments made me think that 200' of 1/4" G40 HT might be just the call. I may be wrong, but at 3/4 pound per foot of chain, that would put me at 150#'s + the 25# Manson Supreme so 175# in the bow. Is that untenable or could I make that work by balancing the boat and keeping the anchor & rode stored below during longer, offshore passages (of course)?

I do have a lot of weight in the stern including the rather heavy Aries Lift-up Vane, an 8HP newer outboard, etc. so that may have some counter-balancing effect I would hope.
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Old 10-03-2010, 17:36   #4
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The WLL of 1/4" G40 is typically 2600lbs with a breaking strength of 7800lbs. For 5/16", it is 3900WLL and 11,700 breaking strength. If you plan to anchor in storm conditions, you should plan to see up to around 2000lbs or so for your boat. This would mean that 1/4" chain is plenty although I do agree that it feels a little flimsy.

Part of what you want to do is to minimize the loads on the chain. This means things like stripping everything when a big storm is expected but it also means providing shock absorption to your system. Since catenary provides very poor shock absorption during actual storm conditions, this means having a really good snubber.

My own reaction to what you have proposed would be to use the lighter weight chain but one size heavier on the anchor if you really are planning on extended cruising. I understand that this isn't really what you asked.
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Old 10-03-2010, 17:42   #5
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Originally Posted by matrix View Post
Thanks daddle -- great info to consider. I agree the depth is a major factor and that the more chain the better...

Your comments made me think that 200' of 1/4" G40 HT might be just the call. I may be wrong, but at 3/4 pound per foot of chain, that would put me at 150#'s + the 25# Manson Supreme so 175# in the bow. Is that untenable or could I make that work by balancing the boat and keeping the anchor & rode stored below during longer, offshore passages (of course)?

I do have a lot of weight in the stern including the rather heavy Aries Lift-up Vane, an 8HP newer outboard, etc. so that may have some counter-balancing effect I would hope.
The concern with weight has more to do with placement than the total weight. Weight in general is bad since the boat will sit below its designed waterline (this is a big problem for someone like you who is planning on extended cruising on a small boat). Weight in the ends is particularly bad since it will raise the inertia of the vessel. This will mean that your vessel will be slower to react in pitch and you can actually have the effect of putting your boat out of phase with the waves.

You can't avoid weight entirely, the key is to put heavy stuff as close to the center of the boat as possible.
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Old 10-03-2010, 17:47   #6
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Agreed 100% about the role of the snubber and although I do still have some questions about the best design, for now I am just trying to iron out the fundamental decision of chain and anchor size.

You bring up over-sizing the anchor and going up to 35# on the Manson Supreme seems well worth the $100 extra or so. I think the 35#'er would provide excellent peace of mind while hopefully also being doable by hand. I can not imagine that 10 more pounds would make it impossible.

I suppose it works both ways - bigger anchor with lighter chain, or "normal" (not oversized) anchor on 5/16" chain...

Thanks!

BTW - Anyone have any suggestions on where to purchase high quality chain? Is 1st Chain supply my best bet?
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Old 10-03-2010, 18:48   #7
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If yo20u have to lift it, a 35' anchor is going to be a chore. A 35# should be adequate for a 15,000 boat, doubt yours weighs anywhere near that. Since you have no windlass, would go with 220' of 1/4" chain and a 25# anchor. Should be plenty of anchor and chain. If you are not going to areas with coral bottoms, you could get by with a lot less chain and more rope. In a blow, chain gives peace of mind. It's not the ultimate strength of a rope rode that's a problem, it's chafe. Not having to worry about that makes life a lot easier.
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Old 11-03-2010, 15:41   #8
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Thanks for that feedback -- I think that 35# Manson Supreme is going to be a chore, and the 25# should be completely sufficient for a boat that is only 8,000#. I like the idea of 220' of 1/4" HT - I'll go that route with a 25# Manson. Thanks!
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Old 11-03-2010, 18:32   #9
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Q: I have a 27' cruising sailboat (similar to an Albin Vega 27) that I intend to cruise full time in the South Pacific in the next year.

A: Similar boat here (27', long keel, 8800 lbs loaded). 10 Kg Bruce + 20 meters of 10mm chain. But in retrospective we should have had longer 5/16 G-40 plus a bigger anchor (I guess 15 Kg Bruce or 10 Kg Rocna/Manson, or better yet a 15 Kg one).

Q: Looking at 1st Chain Supply I see that the weight of 150' 1/4" G40-HT is the same as 100' of 5/16" G-40 HT. I see that the WLL is significantly greater on the 5/16"

A: I would use the 5/16 G-40 (we used 3/8 G-30).

Q: How much weight is tolerable in the bow of a 27' cruising sailboat?

A: Zero. But you will have some - e.g. the anchor may be stored there. It is a good idea to try and keep the chain low and further aft if you can (in our boat the first comp. of the bilge works OK for this purpose.

Q: I have been pulling up 50' of 3/8" G40 and a 22lb Delta by hand for several years in the channel islands, so am hoping that 100' of 5/16" of 150' of 1/4" will be doable w/o a windlass.

A: depending on your physical frame, 15Kg anchor with 100' of 5/16 chain can be manageable. But it will not be very pleasant.

Q: This will be on a Manson Supreme 25# with the CM Brand 3/8" red-pin shackle which comes recommended on these threads....so I guess if I do go the 1/4" HT route I will need to get an oversized end-link, which does not seem too difficult, but is a factor to consider I suppose.

A: Yep. But I would go for 5/16 and then a 3/8 shackle will fit (except the oversize pin one, that will NOT). You can get a HR Wichard shackle to solve any worries about shackle strength.

My 0.02 Eurocents ;-), hope it helps.

b.
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Old 11-03-2010, 19:15   #10
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with your boat I would go with t he 1/4". 27 feet, fairly low windage, fairly fine in the bow (if I remember right) so the weight is not good for you...1/4 should be plenty for your boat...
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Old 12-03-2010, 06:43   #11
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I have a similar sized boat and am interested in recomendations for an appropriate sized windlass for similar sized gear,my preference would be for a manual unit.
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Old 12-03-2010, 07:04   #12
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A “typical” 27 foot sailboat would want an anchor rode rated between 700 to 1,400 (2,100# for a permanent mooring) pounds working load limit (WLL or SWL).
A 1/4" Proof Coil (G30) chain is rated 1,300#, and 1/4" High Test (G4) is rated 2,600#. A 3/8" PC (G30) is rated 2,650#.

Notwithstanding “bigger is better”, and understanding that “more is (also) better”; I’d go with a longer length of 1/4" chain (either G30 or G40 will be adequate), rather than the unnecessarily heavy & over-strength 3/8".

See ➥ NACM Chain Spec's (pg.11) G3, G4, & G7 - National Association of Chain Manufactuirers (NACM)<br /> &quot;Welded Steel Chain Specifications&quot; (13 pages total)<br /> Goto: http://www.nacm.info/Downloads/NACM_Welded.pdf Cruisers & Sailing Photo Gall

And ➥ http://www.cruisersforum.com/gallery...r&imageuser=79

And ➥ Boat Mechanical Systems Handbook ... - Google Books
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Old 12-03-2010, 09:21   #13
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Hey Gord:

1/4 might be OK @ the WLL in easier conditions.

(Although I think it is not good enough given the Pacific anchoring conditions where it is pretty common to have the chain wrapped round a coral head, when it needs to be just as strong as a permanent mooring chain).

BUT

Is it not easier to handle the 5/16 (rather than 1/4) by hand?

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Old 12-03-2010, 12:05   #14
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some great info. the prospect of the chain wrapping around a coral head is especially disconcerting and makes the 5/16" sound good, as a compromise position between the 1/4" and the 3/8". I realize the WLL #'s are the hard data, but in hand the 1/4" is not confidence inspiring.

The south pacific is really my dream cruising destination (although I will start out in Mexico) so I want to design a system suitable for those coral bottom conditions and depths.

You mention that the 5/16" is actually easier to manage by hand? This seems counter intuitive but is it the larger link size that makes it easier to grip and work with?

Thanks for the info everyone. For long passages the anchor and rode would not be stored in the bow, I will try and work out something more suitable. But for coastal cruising it will need to be up there so herein lies the dilemma i guess!
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Old 13-03-2010, 15:48   #15
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I handle 3/8 by hand. It is heavy but comfortable to hold. I would consider 5/16 OK but 1/4 might be a bit not quite easy to hold on by hand. Very easy to try out in a chandlery - just remember to hang a 80 lbs weight on its end.

We had a 22 lbs anchor and 60' 3/8'' chain on the bow of a 26 footer for 6 years, 2 of them in the Pacific. Did not see any issues with "weight in the bow" (where else could it be?); but sure - would prefer to have the weight in the bilge (just could not - because our other chain was already there - we carried 300' of chain and 4 anchors).

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