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Old 26-03-2009, 14:18   #1
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anchor sizes?

Hey folks,

My new boat came with two anchors, both are Danforth 35-pounders.

My boat is 39 feet long, and I'm in the Pacific Northwest... are these anchors big enough to hold me in one place in a decent blow?

I hear that if you deploy two anchors, you run the risk of twisting the rodes together and fouling them - any tips?
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Old 26-03-2009, 14:38   #2
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Just my opinion...Yes, they are big enough to hold you. The Danforth-type anchors can develop tremendous holding power when set right, and oriented correctly. That, however, is the rub. When they are not set correctly, or when your boat veers due to current or a clocking wind, these anchors can easily be tripped, and will not usually re-set.
I would keep one of them, sell the other, and re-invest in a (Delta-Spade-Rocna, etc) anchor that has good all-around performance, and that can re-set well.
Re two anchors deployed at the same time, yes, you can/ will foul the rodes. Better to deploy one large anchor, keeping the 2nd in reserve.
Again, my opinion.
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Old 26-03-2009, 14:41   #3
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not enough weight. your anchors should be at least 30 pounds each for such lenght in my experience.

use search for anchoring in bad weather.
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Old 26-03-2009, 15:35   #4
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It is not hard to avoid fouling - done it dozzens of times.

Quote:
Originally Posted by drew23 View Post
Hey folks,

My new boat came with two anchors, both are Danforth 35-pounders.

My boat is 39 feet long, and I'm in the Pacific Northwest... are these anchors big enough to hold me in one place in a decent blow?

I hear that if you deploy two anchors, you run the risk of twisting the rodes together and fouling them - any tips?
The tricks are:
  • Connect the 2 rodes several feet below the bridle junction, and end the second rode there. Yes, fixes limits the length of the second rode, but if you commonly anchor in certain range of depth, not a problem. By doing this the rodes cannot wrap around each other if the boat spins with the tide. the rode becomes a swivel.
  • There is no point in setting 2 anchors side-by-side. If the wind shiftsat all, the load goes on one, and the other will foul. IF you are unlucky, both will trip into a big ball of useless steel and chain.
  • Set the anchors at a 90 degree angle to each other. Less, and the lazy rode can easily trip the unloaded anchor. More, and the tight rope effect increases the strain. Example:set one at 10.0 scope, set the second there, and bring both to 7.1 scope. Chain will help keep the rodes on the bottom, too.
  • 120-170 degrees can be useful if you REALLY need to reduce swing. Canals. But it is bad if the wind hits from the side.
  • Don't leave the large anchor in reserve; use it when you expect stong wind and a shift. By the time you need it, what I describe above may not be possible.
  • Always keep some wieght, like a kellet, atthe apex of the bridle. This will take the rode to bottom when the tide swings slack, preventing keel wraps and fouling in most cases.
Yes, this is a lot of work to get RIGHT... the reason many report trouble, and so...

I agree that Danforth and Fortress anchors are prone to tripping and are not your best primary. You need a third, anyway. Get one of the new designs (Rochna, Manson, Spade, Delta), perhaps a bit larger.

Enjoy your new boat.
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Old 26-03-2009, 17:05   #5
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I would avoid double anchoring, it's nothing but trouble for sure.. A well set danforth in shell or sand should provide the most holding you can get out of an anchor. In the NW you need a good sand/rock anchor also so condier that for the other one.
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Old 26-03-2009, 18:46   #6
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I hear that so much, yet I have done it dozens of times when changes required...

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I would avoid double anchoring, it's nothing but trouble for sure.. A well set danforth in shell or sand should provide the most holding you can get out of an anchor. In the NW you need a good sand/rock anchor also so condier that for the other one.
And never an incident. So, "trouble for sure" is simply false. Trouble in the hands of the casual; yes, I agree completely. It is a matter of attention to method. Many have read about it in a book, perhaps not well explained, tried it, and fouled in a terrible way. A poor way to learn.

I have always felt strongly that if I EXPECT a strong change in wind force and conditions, why would I ask my anchor to reset? Why would I not be SURE that I had something solid, unimpeachable, set in that direction?

It is not something I do every night. But if I expect that wind is going to rise during the night and increase to 60 knots - and I have been through that many times with hail storms - I sleep without an anchor watch, knowing that I am nailed down against the change.

I guess I learned my anchoring attitude from 25 years of high-level climbing and mountaineering. Blow an anchor system and 2 guys go home in a box. It is not an insurance claim. Set up sloppy anchors, and good climbers won't go with you.

I will also say this; if all you have is 2 fluke anchors, you will either set them at 90-120 degrees when a sharp change (wind or tide) is expected or you will pop them out. It is a matter of time. Danforths only reset some of the time, perhaps 60% on a very good bottom; otherwise less, and in a hard bottom, forget it. It is really in this context that dual anchor advise was offered.
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Old 26-03-2009, 18:57   #7
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Quote:
My boat is 39 feet long, and I'm in the Pacific Northwest... are these anchors big enough to hold me in one place in a decent blow?
My length is 36 ft and the LOA is more like 42. I use a 45 lb anchor (Bruce and CQR plus Danforth). Yes, your anchor should be big enough but by the tables. Going one more size is a good idea if you need serious protection. where you anchor and how you set anchor(s) matters as much as the size. A poorly set anchor is worthless. Having had a mountaineering background like ThinWater there are a lot more issues than just anchor size.
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Old 26-03-2009, 20:53   #8
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My length is 36 ft and the LOA is more like 42. I use a 45 lb anchor (Bruce and CQR plus Danforth). Yes, your anchor should be big enough but by the tables. Going one more size is a good idea if you need serious protection. where you anchor and how you set anchor(s) matters as much as the size. A poorly set anchor is worthless. Having had a mountaineering background like ThinWater there are a lot more issues than just anchor size.
Hey that's pretty much exactly my dimensions and ground tackle arrangement as well. I'm pretty down on the double anchor rig, but can fully admit that maybe it's just because I lack the technique.

I'd get a 45+ pound CQR or Bruce, with 300' of chain. That's a lot of holding power, and CQR's and Bruces are much better than danforths about resetting when they get yanked to the side.

I think this is the part where the guy from Rocna shows up and tells us all how his is better than the rest of the world :-)
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Old 26-03-2009, 21:33   #9
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A well weighted plough...

My recent, though not extensive, experience suggests that a well made plough anchor with a decent amount of lead in the tip might set well under some (mainly mud) bottom conditions.
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Old 26-03-2009, 22:41   #10
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You are in a Searunner, and multihulls tend to have lots of windage. The anchor design needed depends on your cruising grounds - water depth in anchorages, type of sea bed, and wind and sea state. Multihullers sometimes try to use light ground tackle which may work if you are only using it for a lunch hook. But if you are doing more extensive cruising, you should rachet up your ground tackle to match. Two anchors of the same design are redundant and not particularly helpful, If you have two anchors, they should be different designs to give you more options on different seabeds.

I believe that multihulls should use heavier ground tackle than corresponding length monohulls because of greater windage. A bridle with an all chain rode is important, and a lazy loop of chain holding the bridle down increases your security.

A heavy anchor of the right design for your location combined with an all chain rode works wonders.

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Old 27-03-2009, 03:16   #11
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Notice the quite long “lazy” loop of chain, that Dave’s snubber creates.
Some (many) cruisers set too short a slack/lazy loop on their chain, and too short a snubber.
Nice illustration, Dave.
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Old 27-03-2009, 04:10   #12
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Nice pic-Dave!
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Old 27-03-2009, 04:52   #13
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Nice explaination of the "lazy loop" function.

Quote:
Originally Posted by maxingout View Post
You are in a Searunner, and multihulls tend to have lots of windage. The anchor design needed depends on your cruising grounds - water depth in anchorages, type of sea bed, and wind and sea state. Multihullers sometimes try to use light ground tackle which may work if you are only using it for a lunch hook. But if you are doing more extensive cruising, you should rachet up your ground tackle to match. Two anchors of the same design are redundant and not particularly helpful, If you have two anchors, they should be different designs to give you more options on different seabeds.

I believe that multihulls should use heavier ground tackle than corresponding length monohulls because of greater windage. A bridle with an all chain rode is important, and a lazy loop of chain holding the bridle down increases your security.

A heavy anchor of the right design for your location combined with an all chain rode works wonders.

Attachment 7563
Almost like a kelet, but not prone to whipping under strong conditions and easy. I never thought of it that way. I have always used some heavy fittings at that point with a fiber rode, to keep the bridle down during light load, to prevent keel wraps, and reduce the chance of anchor fouling.
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Old 27-03-2009, 08:15   #14
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more holding at less weight..

For a multihull, as the windage is more important, you should select at least one size bigger than the standard Manufacturer’s suggestion...

But multihulls don’t like too much weight at the extremities, then you should consider that nearly all « New Gen » anchors are much more efficient that the « past century » models, and you could have both a bigger anchor (more holding) for less weight

– I will suggest you to look at manufacturers suggestions and as well as characteristics of anchors and to select the anchor which has the largest surface area for the lightest weight,

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Old 27-03-2009, 08:29   #15
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Quote:
Originally Posted by maxingout View Post
You are in a Searunner, and multihulls tend to have lots of windage. The anchor design needed depends on your cruising grounds - water depth in anchorages, type of sea bed, and wind and sea state. Multihullers sometimes try to use light ground tackle which may work if you are only using it for a lunch hook. But if you are doing more extensive cruising, you should rachet up your ground tackle to match. Two anchors of the same design are redundant and not particularly helpful, If you have two anchors, they should be different designs to give you more options on different seabeds.

I believe that multihulls should use heavier ground tackle than corresponding length monohulls because of greater windage. A bridle with an all chain rode is important, and a lazy loop of chain holding the bridle down increases your security.

A heavy anchor of the right design for your location combined with an all chain rode works wonders.

Attachment 7563

Is this the best method of anchoring? I usually lower chain and let the windlass take the strain. Now you have me thinking that I'd be better off putting the load on a cleat, using a bridle.

Is is really bad practice to leave the strain on the windlass?
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