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SV Skalliwag #141
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I have read about placing to anchors in series for better holding during high winds. How/where do you attach the add on anchor? I remember it was descibed I think on Cruising Mag but I didn't get it.
 

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Brokesailor-

You're talking about tandem anchoring, and it has been discussed quite often on this forum previously. However, I generally don't recommend it, as a properly sized primary anchor should be sufficient to the task. If it isn't your ground tackle is undersized at best.

Part of the problem with using tandem anchors is that it is very difficult to set the two anchors sufficiently. If the two anchors are the same design, the primary anchor will usually set before the secondary, because it is closer to the boat, and the load on the anchor rode will cause it to set, and unless the connection between the two anchors is perfectly taut when you start backing down to set them, the first will set before the second gets a chance to.

Some anchors have a specific attachment point on the crown of the anchor for tandem anchoring setups. That is generally the best location to use to attach the two.

The anchors should be separated by at least a boat length of chain IMHO. Anything less than that will generally mean that the secondary anchor is trying to set in ground disturbed by the primary, reducing the holding power it can generate. This is also a big reason why a larger single anchor makes more sense than two smaller anchors.

Finally, if the tandem anchor setup is exposed to a reversing wind/current, the two anchors may foul one another, preventing the setup from resetting properly. This is far less an issue with a properly sized single anchor.
 

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When his wife is aboard, he is most definitely a cruiser, regardless of what he thinks. :)
Good thing our Portuguese friend doesn't post in "Cruising" very often...because he doesn't think he's a cruiser!
 

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Brokesailor

Don't believe everything you read in the papers . . . . . .

A properly sized anchor will hold you when things are normal or even slightly abnormal. An oversized anchor will do it better but will be a PITA in other ways. Any prudent cruiser will have AT LEAST two anchors on a vessel. Some carry a lot more (I try to have 4 when I'm sailing long distance).

When the situation calls for more than the "properly sized" anchor will deliver (strong wind coupled to tidal surge and once for me, a flowing river) then two anchors are better.

Dual anchors in a V formation work for some but wouldn't be my choice for a range of reasons. Tandem anchoring is IMHO far better.

One thing I will agree with is a decent length of chain between the anchors and one boat length ain't enough. I have done this more than once and I let the first anchor out on 25 metres of chain, let out the rode until the second anchor is not quite ready to dig. Then I pull back, dig the front anchor. Then I motor forward and let the second anchor hit the bottom and pull back while the rest of the rode goes out.

Remember too, if you need two anchors, the reality is you also need a lot more rode out than you ordinarily would use.

So in short, if you reckon you're going to need some extra comfort to sleep well, there is nothing wrong with using two anchors. Yes, they're a bit of work when the tide changes direction but tandem anchors hold very strongly.
 

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Andre, would you say that in a tandem anchoring situation that you start counting the scope from the second anchor (the one closest to the boat) and try to get 7:1 or better from there, or are you advocating even more scope and rode?
 

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Andre, would you say that in a tandem anchoring situation that you start counting the scope from the second anchor (the one closest to the boat) and try to get 7:1 or better from there, or are you advocating even more scope and rode?
I'm just suggesting that if there is a need to deploy tandem anchors, the conditions are likely to be pretty demanding and when they are, the more rode the better. Deploying tandem anchors is not easy and managing them when things change is even more challenging so I wouldn't do it unless there was a genuine need.

I normally deploy 5-1 and if the conditions suggest tandem anchors I would go with 7-1 from the second anchor .

Also just have a care if there are other boats anchored nearby because if they deploy significantly less, you could end up swinging onto them.
 

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I have read about placing to anchors in series for better holding during high winds. How/where do you attach the add on anchor? I remember it was descibed I think on Cruising Mag but I didn't get it.
Val..luckily I read all forums..eheheheh


Brokesailor..(now that's a funny name!!)...

If you read and do everything you read here, you will endup sailing a Cabo Rico or a Valiant built in 1234 B.C., with no sails (sailing is dangereous, and those don't sail anyway)..with 3 extra hulls, 12 bbq's, a brand new 3200HP Caterpillar engine, and be freightfull of sailing for the rest of your life...

read this bellow....and go anchor with a tandem set up...AT LEAST TRY IT YOURSELF...DO IT....I have beed doing it for over 20 years and am still here..fishing vessels in my country do it since the time of Vasco da Gama...

I wrote this HERE


I anchor many many times in a place called Culatra Island, here in Portugal.

It has 3 to 5 knot currents twice a day, in both directions.

I have been using the tandem method here, for over 20 years, and never draged once. Do it only one anchor I don't care what anchor.....and bye bye...

I use a smaller Danforth anchor (14kg) with 10 feet of rope, attached to the "head" of my main anchor, a 28Kg plow, then chain, then rope. Here is what everyone uses, or you're dragging all the time.

Works for me, and for the others. Our bottom is mud / sand / weed.

Some say its a disater waiting to happen (specially Craig Smith of Rocna, but he is he, and I am me....,) if the smaller first anchor rolls around the primary as the boat circles with the current. So far in over 20 years no problem what so ever.

I do it.

Here is a drwing




then go HERE

HERE
 

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I fear the simple explanation belies the complexity of the operation. What Giu has diagrammed is simply an anchor resetting device; one that aids the primary anchor resetting on the change of the tide. I, like many others, think that either a single anchor well set or a Bahama moor would be superior to the method shown, certainly in terms of ease of use and lack of fouling.
 

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Sway--

Unfortunately, too many boats have woefully undersized anchors and are going to be in serious trouble should they be caught anchored out in a storm unexpectedly.

I fear the simple explanation belies the complexity of the operation. What Giu has diagrammed is simply an anchor resetting device; one that aids the primary anchor resetting on the change of the tide. I, like many others, think that either a single anchor well set or a Bahama moor would be superior to the method shown, certainly in terms of ease of use and lack of fouling.
 

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I, like many others, think that either a single anchor well set or a Bahama moor would be superior to the method shown, certainly in terms of ease of use and lack of fouling.
Sway, I agree that in the first instance a single anchor is better than any twin setup but when that doesn't hold . . . .

And I concur fully with the description offered in the link provided byCraig Smith on Bahamian anchoring. The couple of times I tried that I ended up spending more time untangling two chains than sleeping and that makes me grumpy. I don't even bother trying it anymore. And setting anchors in the Bahamian way is a ***** unless you have the balls to get in a dingy to set the second anchor in what must already be very inclement weather (else why bother?).

When you motor up at an angle to the first anchor it's near impossible to keep track of where it is to set the second one in the right spot. And if you get it wrong, one of them will drag until the rodes are bearing equal load. Unfortunately at that point, the anchors are already far closer together than you would have liked.

The tandem setup is way better. JMHO.

When warranted, I use exactly what Giu sketched.
 

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So what size do you consider right for which boats?

Sway--
Unfortunately, too many boats have woefully undersized anchors and are going to be in serious trouble should they be caught anchored out in a storm unexpectedly.
I know anchors depend on bottom and boat size and displacement so here is mine...

I sail a 6800lb fin keel 27' boat (Catalina 27) in the relativly protected waters of The Chesapeake Bay. I have 3 anchors; an 8S Danforth with 6' of chain and 75' of 3/8" nylon rode. This is my "lunch hook". I also have a Danforth 12H 6' chain and 120' of 1/2" nylon and a 7lb Fortress with 10' of chain and 200' of 1/2" nylon. The overnight and "go to" storm anchor is the 12H Danforth. I have never dragged anchor in that and have survived once in a 1 hour storm in somewhat open water (protected to windward by land 1/2 mile away) and blowing 45 knots. The ride was "interesting" and the GPS track showed a nice arc as we swung around, but we held firm. It was all I could do to recover the anchor after the storm.

So what single anchor do you reccomend?
 

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Danforths and Fortresses are horrible anchors in situations where the current or wind can reverse... since they can often be fouled and not reset. IMHO, you were fairly lucky not to drag.

If you're going to be anchored out overnight, I'd recommend going with a Delta FastSet 22 lb. at a minimum. A Rocna 10 (22 lbs.) or Manson Supreme would probably work very nicely as well, and have more holding power than the Delta. I'd add 30' of 1/4" of chain and use 1/2" octo-plait nylon for the rest of the rode. This would probably hold your boat an unprotected anchorage at 45 knots... probably even more than that.

I know anchors depend on bottom and boat size and displacement so here is mine...

I sail a 6800lb fin keel 27' boat (Catalina 27) in the relativly protected waters of The Chesapeake Bay. I have 3 anchors; an 8S Danforth with 6' of chain and 75' of 3/8" nylon rode. This is my "lunch hook". I also have a Danforth 12H 6' chain and 120' of 1/2" nylon and a 7lb Fortress with 10' of chain and 200' of 1/2" nylon. The overnight and "go to" storm anchor is the 12H Danforth. I have never dragged anchor in that and have survived once in a 1 hour storm in somewhat open water (protected to windward by land 1/2 mile away) and blowing 45 knots. The ride was "interesting" and the GPS track showed a nice arc as we swung around, but we held firm. It was all I could do to recover the anchor after the storm.

So what single anchor do you reccomend?
 

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A rule of thumb is 1 pound of anchor for every foot of length. Use the biggest that you can handle on your bow roller. I would not rely on a lunch hook even for lunch if there is wind over about ten knots or any significant current. I agree that danforth style anchors are great when the wind direction and current do not change, but not reliable when they do. They will definitely bury themselves deeply in Chesapeake mud though. Delta or Bruce style anchors are proven and work well.

I see no need for tandem anchoring. Properly sized and set anchors of the right design do not need to be used in tandem. If you have a boat anywhere near forty feet, the problems of retrieving your tandem anchors when you are ready to go will likely cause you a back injury or at least an hour of total frustration (as will two anchors set in a Y). A single anchor is the best way to go unless you are battening down for a hurricane.
 

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This rule of thumb isn't all that accurate, since a 16' boat rarely needs a 16 lb. anchor, and much will depend on the design of the boat. Boats that have significantly more windage, like multihulls, will generally require a heavier anchor than would a flush-deck racing monohull of the same LOA. If the guys at your marina are laughing about how big the anchor on your bow roller is, then you're probably in the right ball park.

A rule of thumb is 1 pound of anchor for every foot of length. Use the biggest that you can handle on your bow roller. I would not rely on a lunch hook even for lunch if there is wind over about ten knots or any significant current. I agree that danforth style anchors are great when the wind direction and current do not change, but not reliable when they do. They will definitely bury themselves deeply in Chesapeake mud though. Delta or Bruce style anchors are proven and work well.
IMHO, tandem anchoring is generally the sign of an undersized primary anchor. Tandem anchoring and Bahamian moors make retrieval much more complicated.

If you're battening down for a named storm—you should probably be seeking the most sheltered waters you can find and using every dockline, long warp and anchor you've got to secure the boat.

I see no need for tandem anchoring. Properly sized and set anchors of the right design do not need to be used in tandem. If you have a boat anywhere near forty feet, the problems of retrieving your tandem anchors when you are ready to go will likely cause you a back injury or at least an hour of total frustration (as will two anchors set in a Y). A single anchor is the best way to go unless you are battening down for a hurricane.
 

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McCary...The Chessie is one of the easiest places to anchor as it is almost all mud bottom and there are no strong currents and modest tide. A Fortress with the 45 degree mud setting is probably as good as anything but yours is rather undersized. In the Chessie it is all about penetration and fluke area in my opinion. For that reason...I would go with a Rocna or Manson Supreme rather than a Delta which I've had drag when the bottom gets really soupy. These new anchors give you additional security over the Fortress when they need to re-set as in when the wind does a 180 in a squall coming across the bay. The galvanized 25lb Manson should give you all the performance you will ever need in the bay at a reasonable price.
 

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If you have a boat anywhere near forty feet, the problems of retrieving your tandem anchors when you are ready to go will likely cause you a back injury or at least an hour of total frustration (as will two anchors set in a Y).
If you have a boat anywhere near 40 feet you should really be considering a windlass.:) Easy, fast retrieval and the only effort is pushing a button on my deck with my big toe.
 
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