|Topic Review (Newest First)|
|12-14-2008 09:47 AM|
First of all I am not a fan of two anchors down at a time especially the Bahamian moor due the the twisted mess after a few tide changes.
I use the Bahamian at Beaufort NC because of the lack of space and that is what every one else does (etiquette 101). I often use fore and aft anchors in narrow channels in the Georgia ICW because there is NO room to swing sometimes even putting them on shore.
I have used tandem anchors in several high gales and one tornado and was so impressed that I actually got some sleep. My method ..... I let out about 25% of the rode on my primary and then connect my secondary anchor to the primary rode with a stainless steel carabiner and then let out more of both rodes (all chain)and because of the slip of the carabiner they both set at their own speed. The carabiner allows the second anchor to move up & down the primary rode and acts like a 44lb. kellet. Yes it took some thought and a little practice but as I said, I slept.
|12-13-2008 08:29 PM|
I think there is some confusion as to the Bahamian moor and how it is executed and for what situations. Generally speaking it is used for a reversing current or anticipated reversing winds. Thus, after completion, one's boat is riding to her first rode dead ahead while the other rode tends aft in a straight line form the first. When the current shifts the load is transferred to the slack rode and that then becomes the primary anchor.
If you place these two anchors each broad on their respective bows you've conducted a bridle moor. Each anchor will tend approximately four points (45 degrees) to it's respective bow. The direction of maximum wind or current should bifurcate the 90 degree angle between them. The great advantage to this moor is not so much increased holding power but reduced horsing of the boat. You are locking the bow down in position reducing yaw. If you can reduce yaw you will substantially reduce the shock loading on your anchor rode. And, like all strains on gear, it's the shock load that is going to most often assure that something either breaks or breaks loose. This mooring also gives a much better chance of resetting an anchor, already deployed, than one would get attempting to set another anchor after the first is dragging. The anchors can drag respectively and have the opportunity to re-set independently. That is until they meet and then all bets are off...but not lost.
In particularly violent weather it may make sense to use the hammerlock moor which is a slightly modified version of the bridle moor. You'll set one anchor and then sheer off and drop the other to a shorter scope. You'll use this anchor, which may set and re-set, to limit the amount of yaw thereby preserving the hold the primary anchor has established. It is particularly useful in areas like the Chesapeake where the bottom is soft mud. In fact it was invented there by a USN LST, I believe, riding out a hurricane.
If you're yawing severely it's doubtful that any anchor is going to hold adequately, or any anchor rode. Reducing yawing by mooring is the best way to improve your holding power. And we'd be remiss if it wasn't mentioned that use of the engine and rudder can ease the vessel's motion and strain on her rode as well.
Retrieving an anchor is another subject entirely and frankly not germane to this discussion. After all, you can always buoy and slip your rode to return and retrieve it later, once it's done it's job of holding you in place through the maelstrom.
|12-13-2008 08:23 PM|
"Anchor size" is one of those threads that can go on forever. "What's your favorite anchor?" is the companion thread. It also goes on forever. However, both are important questions and should be discussed and debated. Please allow me to offer my 2 cents (If I mention a specific anchor in this post it is NOT and endorsement of any manufacturer or design! Pick whatever works best for you in your local conditions, not what works for me.)
I'm a firm believer in KISS; keep it simple stupid. My anchoring philosophy revolves around this principle. I'm also a firm believe in "practice makes perfect".
IMHO bigger is better. I have chosen anchors and rode rated for boats bigger than my Hunter30. Oversize anchors, attached to 12' of chain and nylon rode have worked for me in all types of conditions; from NY to the Bahamas I believe that the more anchor weight that hits the bottom, the deeper and quicker it will set.
As far as rodes go, unless you routinely anchor over coral reefs or other abrasive bottoms, I never understood the need for all-chain rodes. First, it adds a tremendous amount of weight to the bow of the vessel and it's a real PITA to retrieve without a good windlass. For the all-chain users, dropping a big pile of metal on the bottom does not constitute anchoring. It may work just fine in calm conditions, but as soon as the wind picks up and the chain plays out, you're SOL. Seems you never actually to set the anchor. Snorkel around a couple anchorages and you'll know what I mean.
I know, chain is stronger. But how many hurricanes to you plan to ride out in your vessel? The elasticity found in a nylon rode may help to make up for its different tensile strength.
The second most important part the anchoring equation is choosing the right anchor for the bottom conditions. Personally, I carry four anchors. My primary is a 35# Delta. My secondary is a 33# Bruce. Both are attached to 12 ft. of chain and 150 ft. nylon rodes. I also carry a 30# Danforth and a 15# claw anchor.
In the Bahamas I use the Delta almost exclusively. It penetrates sand quickly and is sharp enough to penetrate grass (especially if I dive on it to force it into the bottom) The Bruce is there in case I encounter a muddy bottom. It held like crazy on my last boat when I spent most of my time on the Hudson River. The claw anchor is collapsible and works great in a rocky area, or at the edge of a coral reef. The Danforth serves as my storm anchor.
Keeping to my KISS philosophy, I seldom deploy more than one anchor. I must admit that when a 40 knt. squall roared through my anchorage one morning, I motored into the wind for awhile to take the strain off the anchor . The next time the weather report called for similar conditions, I used the Bahamian moor to deploy both bow anchors. Everything worked just fine until I had to dive down to untangle the rodes. Same thing happened the next time I tried this technique in Nassau Harbour. For this reason I tend to anchor away from those folks who deploy two anchors. I will happily swing around my one anchor, keeping a regular anchor watch.
Laying out the proper scope is where many novices run into problems. For most situations, I find a 5:1 ratio to be sufficient. If a blow is expected, I'll go to 7:1 or greater. If you have any doubts, dive your anchor to see how your boat pulls on it. If your rode is lying flat against the bottom, any horizontal pull will serve to set the anchor more firmly. If the rode is rising clear of the bottom, the upward movement is apt to dislodge the anchor. Keep it simple. More wind, more rode.
Proper anchoring is not rocket science. It's common sense, reinforced by lots of practice.
|12-13-2008 07:08 PM|
SY that is not true..
I have a rather small windlass a Lewmar 900 and it lifts both anchors with ease. The main is 28 kg and the tandem is 14 Kg..that almost 82 lbs, plus the chain.
I motor slowly ahead, and winch them up as I go...no problem what so ever, so far.
And I onbly anchor tandem when i go to Culatra Island..all other times I only use the main anchor
|12-13-2008 07:04 PM|
|SYMandalay||A windlass does a fine job of getting one anchor on board but that second one is a female dog.|
|12-13-2008 04:23 PM|
Originally Posted by SYMandalay View Post
|12-13-2008 09:03 AM|
|camaraderie||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.|
|12-13-2008 07:39 AM|
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.
Originally Posted by SYMandalay View Post
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.
|12-13-2008 07:14 AM|
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.
|12-13-2008 02:30 AM|
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.
Originally Posted by mccary View Post
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