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12-06-2008 10:01 PM
sailingdog Umm, not exactly applicable to a Pearson 36-II, which displaces a bit over 15000 lbs... is it... if it isn't applicable, why post it, especially out of context???

You also haven't answered the question about your relationship to the book.

Originally Posted by pdqaltair View Post
I did say the information was unconventional. It was also presented out of full context.

A concern for small boats is weight in the bow; a 25 pound anchor and 150 feet of 5/16-inch chain is about 175 pounds, and that is just too much for boats the barely weigh 1000 pounds. A small boat will not have a windlass, so this gear has to come in hand-over-hand; a different approach is needed, and a second anchor and rode will be on-board anyway. With rope and light weight anchors, a small person can easily manage the work, which involves a few more steps but is quick and physically easy.

The advise was given for severe anchoring conditions; strong tidal flows and powerful thunderstorms with no protection available from the wind. Barrier island areas are often like that, lacking tree-lined coves, and the lower Delmarva more so than most.
12-06-2008 02:12 PM
Originally Posted by sailaway21 View Post
Anchor alarms, be they GPS or Loran, etc..., are about worthless in my opinion. If you've got enough scope out they're going to be giving you false alarms, that is, if you've programmed them accurately enough to reflect dragging. [/url]
I use a GPS anchor alarm most nights. Yes you do get woken up if the wind changes direction significantly even when the anchor is not dragging, but under these circumstances I like to check the anchor is still set with the new wind direction and /or we are not too close to other boats. There is also often a brief increase in wind strength that accompanies a major change in direction.

Several times it has alerted me to a true dragging situation. (yes I have to get a new anchor)
12-06-2008 12:53 PM
Lightwieght gound tackle

I did say the information was unconventional. It was also presented out of full context.

A concern for small boats is weight in the bow; a 25 pound anchor and 150 feet of 5/16-inch chain is about 175 pounds, and that is just too much for boats the barely weigh 1000 pounds. A small boat will not have a windlass, so this gear has to come in hand-over-hand; a different approach is needed, and a second anchor and rode will be on-board anyway. With rope and light weight anchors, a small person can easily manage the work, which involves a few more steps but is quick and physically easy.

The advise was given for severe anchoring conditions; strong tidal flows and powerful thunderstorms with no protection available from the wind. Barrier island areas are often like that, lacking tree-lined coves, and the lower Delmarva more so than most.
12-06-2008 12:31 PM
Valiente I'm surprised nobody's said "to hell with kedges!" yet....

Except for the latest opinions on the Rocna/Manson/Bulwagga anchors, which it lacks, I recommend Earl Hinz's Complete Book of Anchoring, where many of the more "esoteric" anchoring techniques are discussed, plus the advantages of using a bridle, waterline snubbers, etc. About the best book on the subject I can recall.
12-06-2008 11:34 AM
Originally Posted by pdqaltair View Post
From "Circumnavigating the Delmarva Peninsula - A Guide for the Shoal Draft Sailor", by permission:

This is rather long, but there is some good information here, specific to the area and lighter anchors and lighter boats, some of it non-traditional, but all well proven.

Anchoring. Secure overnight anchoring is central to successful cruising, and tales of misadventure abound. Dragging can certainly cause damage to your boat and others, or result in serious grounding. Lack of sleep, pondering whether your mooring is secure, will detract from your enjoyment of the trip and contribute to poor decision-making. A good night sleep may be the largest single safety requirement for the crew. Finally, rates in resort area marinas are ridiculous, and building a sound mooring will allow you to leave your boat for free while you explore.
• Holding ground. Hard clay, oyster shell, and occasionally very soft mud, silt, or heavy weed are unsuitable. There may be no anchor type that can penetrate or hold, or the penetration and holding may be unreliable or difficult to gauge. If possible move to firm sand or sticky mud. No anchoring system can ever be better than the medium at the bottom.
Good advice. I'd also recommend sand, but that's pretty scarce in the Chesapeake.
• Anchor type. Danforth pattern anchors are by far the most popular, and for good reason. They are light, cheap, and powerful in sand and mud. I carry a 13-pound and an 8-pound Danforth type. The aluminum Fortress designs are excellent, but I have found them less than effective in hard clay or shell. A dumb, heavy Danforth imitation can work just as well, since breaking strength isn't at issue for smaller boats, while the ability to sink through soft mud and silt or bite hard clay often is.
Bad advice IMHO. Danforths are lousy anchors for overnight use—especially if the wind or current reverse.

Sharpening the flukes with a grinder and removing excess flange material near the tips can also help anchors bite into hard bottoms or cut through vegetation.
Again, bad advice IMHO, since grinding the edges of the flukes also removes the galvanization—which will allow corrosion to quickly eat away at the steel of the anchor.

Attention to detail is why genuine Danforth and Fortress anchors bite so predictably. Because Danforth style anchors are close to useless on oyster shell, rock, or very hard mud, I carry a 12-pound Northill, though a Delta or other hooking/digging anchor would certainly do as well.
A northhill, which looks like this:

is a lousy anchor in oyster shell, rock or very hard mud, unless it is very large. It doesn't bite all that well or hold well, and is primarily dependent on its mass to keep it in place. Also, if the current or winds reverse, you stand a good chance of fouling the unburied fluke with the rode and pulling the anchor free with no chance of it resetting.

It is important to understand the character of the anchor you are using: a Danforth in a good bottom will stand a straight pull until it breaks... unless the direction of pull changes more than 90 degrees, whereupon it will lift out and probably not reset; a plow-type will reset and vear, but it will also drag through soft mud when the force becomes very great, so they cannot be even a little too small and some shifting or dragging in a powerful squall is to be expected and planned for. A Danforth requires only a little chain, the plow-type requires a good length of chain for its reset properties to function. Neither is better - they are two different things. Plow-types are handy on a big boat with a winch and bow roller to handle the mass or anchor and chain, fluke types are common small boats where the anchor must be handled manually.
The next generation anchors, like the Rocna, Spade, Manson Supreme, etc., are far less likely to move through soft mud, having either flat or concave blade faces—causing the mud to pile up in front of them rather than pushing it to either side. They're generally far better than plow-type or fluke-type anchors in performance, especially if the winds/currents reverse or shift.
• Rode. Three 150-foot nylon rodes are required, doubled braid being best as it will not hockle in use, with five feet of chain or cable at the anchor end for abrasion resistance. I use retired rock climbing ropes, which perform better than any anchor rope made; they are carefully engineered to resist abrasion, absorb impact, and handle easily. These can easily be obtained for a song either on e-Bay or at the local climbing practice area. They are pampered, carefully monitored, and retired after a few seasons, only just broken in. Mark the rode at regular intervals; mine is marked every 30 feet (5 fathoms) with cable ties. This will allow you to correctly measure scope and gauge the arraignment of multiple anchors.
Octo-plait is much better than double braided lines or three-strand for use as anchor lines. Double braid is also less elastic than either three-strand or octo-plait. Double-braid is impossible to properly splice to chain and requires the use of a thimble. This becomes a serious problem if you use a chain/rope anchor gypsy on your windlass, since the thimble will cause the rode to jump out of the gypsy. Using retired line of any type is just stupid and foolhardy IMHO. You don't know what condition the line is in internally or what kind of strains it was exposed to—meaning that you're depending on a relatively unknown quantity for your security.
• Remember the tide. I'm so used to the nonexistent tides of the middle and upper Chesapeake Bay that I easily forget that the water goes down 4-5 feet near the ocean. Allow for a minimum 7:1 scope a high tide; however, in shallow, un-crowded anchorages with strong currents, there is no reason to use less than 10:1 scope.
Calculate your scope based on the high-tide depth plus height of the bow roller off the water. If you're anchored in 10' of water at low tide, with a tidal range of 5' and your bow roller is 3' off the water, for a 7:1 scope, you need 126' (70+35+21) or so of rode out—not the 70' you'd think due to the 10' depth you're currently in. 10:1 scope is pretty much unnecessary, unless you're expecting storm conditions. BTW, anything beyond 8:1 does very little to add any real benefit.

• Two anchors for wind and current shift. It is important to understand is that multiple anchors do not always increase the holding power of your mooring versus a single anchor. Certainly two anchors placed side by side can provide improved holding in a poor bottom, but only if the wind remains in a constant direction, and with Chesapeake Bay thunderstorms that is unlikely. If the anchors are set at an angle of between 0-90 to each other, even a modest change in wind or current will swing the boat far enough to one side to place the entire strain on one anchor. If the anchors are set at an angle of 90-180 to each other, the load on each anchor is greater in a crosswind than if there were only a single anchor—potentially many times greater; consider the considerable leverage a tight-rope applies. Thus, a protected anchorage is still required. However, well separated anchors do maintain the angle of pull on each anchor in a consistent and controlled range of directions. A compromise is required. My typical anchoring method in 10 feet of water: lower the first anchor and pay out 100 feet of rode while backing down, lower the second anchor and pay out 70 feet of rode while backing toward the first anchor, simultaneously take in the first rode to about 70 feet, just sufficiently to prevent propeller fouling. This is neither a bahamian moor nor lying to open-hawse, but is more appropriate to the tides and thunderstorms of the Chesapeake Bay and barrier islands. A properly sized light weight anchor with adequate scope is exceptionally strong when well buried in a good bottom—that is, anything but very soft mud—it should not pull out in any protected anchorage in any squall. At the same time, we know a danforth is weak when pulled 90 off-line, and virtually useless if the direction is reversed 180. A light breeze will remove it, and with any sort of sticky Chesapeake mud or oyster shells clogging the flukes, there is very little chance of resetting. Setting two anchors at a 90 degree angle ensures that the anchor pull will remain within 45 of the setting direction.
You're far better off with the simplicity of using a single, properly sized anchor, rather than two smaller anchors. If your boat veers and the anchors are not properly sized to hold it, it may pull one free and then when it swings back, all the load will be on the remaining one... A properly sized single anchor is simpler to launch, retrieve and use. Using multiple anchors on a regular basis says much about your ground tackle being improperly sized to begin with.

• Three anchors make a mooring. With three anchors the pull will be within 20 of the initial setting direction. The following general procedure can be used in 10 feet of water: lower the first anchor and back down 100 feet, lower the second anchor and back down 100 feet at 60 degrees to the first course (at this point both lines will come tight), lower the third anchor along with 70 feet of rode, while pulling the other lines into about 60 feet. All three lines should be tight. Ease all lines to 70 feet and back down on each anchor as needed. My anchoring practices evolved from my mountaineering background; the American Mountain Guide Association teaches that every climbing belay anchor should be SERENE. Solid-Every part. Redundant. Equalized. No Extension should one element fail. An additional requirement, unstated but implied by the first requirement, is that the direction of pull on each anchoring element does not change in the event of a fall. Rock climbing anchors, though capable of holding up to 5000 pounds in the intended direction, can be removed with fingers alone when lifted in a counter direction. So it is with light weight boat anchors; they hold a strong pull in one direction, but cannot be relied upon to withstand a veer or reset if the direction of pull changes. It takes three anchors to fully meet the intent of this requirement, and that’s what I need to leave the boat for an extended period and remain relaxed. There is significant experience indicating boats weather hurricanes just as well lying to a triangle of three Danforth (large) anchors as to concrete moorings. Perhaps the consequences of a failed mooring are less mortal than those of a failed climbing anchor high on a massive cliff, but the basic principles are the same.
Again, the use of multiple anchors for anything less than a semi-permanent mooring, means that your ground tackle is woefully inadequate.

• Bridal for multi-hulls. Anchored by one hull, catamarans often sail about so furiously as to jerk the anchor out, or at best make for a restless place to sleep, and yet sit perfectly still when rigged using a bridal. Measure the bridal legs to create 30-degree angle at the apex. Keeping the centerboard down and the rudders up further reduces motion.
Bridles are good for most boats that have a tendency to swing at anchor. Bridals are only good if you're planning to get married.
• Keel wrap. When multiple anchors are laid without enough slack for the unloaded (leeward) rode to lie on the bottom, the keel, rudder, and prop can foul on the leeward rode when the wind or tide shift and the boat spins. In a protected anchorage with minimal currents, proper slack will avoid this; the unloaded rode will lie safely on the bottom. The loaded rode or rodes stay safely in front of the boat, away from the keel. However, if an opposing tide and wind is probable, a 10- to 20-pound sentinel weight 10-15 feet down will keep the rode away from the keel. It is simply impossible to predict where the current will blow the rodes while the wind pushes the boat according to its own whim. The following anchoring method is typical in 10 feet of water: lower the first anchor and pay out 100 feet of rode while backing down, lower the second anchor and pay out 70 feet of rode while backing toward the first anchor, simultaneously take in the first rode to about 70 feet, just sufficiently to prevent propeller fouling.
A sentinel will help prevent keel wrap. On boats with centerboards or swing keels, retract them completely when at anchor. If not, you may end up snapping them off when they get wrapped by the anchor rode.

Anchor Available on Deck. An anchor and rode must be accessible within 30 seconds when near shore. Three times, while single-handing, I have experienced engine failures in harbor areas, and having the hook immediately available made each into a minor incident. One was within 50 feet of a rock jetty, with a 30-knot breeze blowing at an angle. Boy, did that anchor look pretty.
Good advice. An anchor is an important bit of safety gear. Dropping anchor can often give you the time to deal with a problem safely, without rushing. A good idea is to have an anchor available at short notice in the cockpit. This can be especially important when transiting rivers or other areas with relatively strong currents.


Just curious, but is the book, "Circumnavigating the Delmarva Peninsula - A Guide for the Shoal Draft Sailor", that your quote is out of written by you or someone you know??? I've noticed you seem to be pushing the book fairly heavily in the Delmarva 2009 thread and was curious. If you do have a relationship with the book's author, that should probably be disclosed per the full disclosure policy of the forum here.
12-06-2008 11:27 AM
josrulz Thank you all for the thoughtful and informative replies. It's all great stuff to think about and apply to our "new to us" boat (once we have it, hopefully this Spring)!
12-06-2008 11:08 AM
sailaway21 Had it been your own ground tackle, I'd suggest you add another ten feet or so of chain to it. The extra chain would not only help the anchor to set and reset, it also reduces the abruptness of your swing when the wind shifts. Let me rephrase that. The boat will still shift her head quickly as the wind backs violently but the chain rode will move more slowly reducing the shock loading to the set anchor.

I recommend setting your anchor more aggressively in mud unless it's just a lunch anchoring duration. You'd like to really bury the anchor as mud causes potential problems with all anchors in resetting due to fouling of the flukes.

The Bahamian moor that Dog refers to is where you set one anchor, say, in the direction the wind or tide/current lays you now. Pay out approximately twice the rode desired as you back in the direction (usually downstream) you wish to set the other anchor. Set the other anchor when at double scope on the first and then back down on the second anchor while heaving home the first rode. When the rodes are approximately equal you're set. Yes, absent the use of a swivel, you can foul each rode upon the other. But connecting them with a swivel eliminates the ability to heave/slack on either.

I wrote the below for a different thread on the subject:

I also advocate more rather than less chain as the chain does a good part of the holding by virtue of weight and catenary.

The previous remarks on signs of dragging should be remembered. Anchor alarms, be they GPS or Loran, etc..., are about worthless in my opinion. If you've got enough scope out they're going to be giving you false alarms, that is, if you've programmed them accurately enough to reflect dragging. Your fathometer or depth sounder alarm is likely to be more reliable. Couple that with anchor bearings, day and night versions as necessary, and you'll be fine.

Chain rode is easier to determine if dragging. It's worth dragging an anchor to observe the phenomena-intentionally dragging one on short scope that is. The chain will do the bunny hop as we used to call it. As it tightens and releases the chain will vibrate and give a hop, and repeat the same thing. If you're feeling vibration on an all chain rode, you're probably dragging.

A rode of line is tougher to determine but you'll want to look for the bunny hop also and the slack followed by tight of the rode.

If you've got a stand-by anchor ready, maybe in the cockpit as Dog suggested, don't throw it over the stern if you become aware that you're dragging. Deploy it from the bow or, if from the stern, walk it to the bow. Unless you have to for some reason, there is nothing worse than being moored fore and aft. The stern bower removes all ship-handling abilities you have until cast off. It'll also keep you from swinging which the rest of the anchorage is probably counting on you doing.

If you're confronted with an area where swing room is unavailable with an impending wind or tide shift, you can moor. Mooring also does one other important thing; it reduces yawing, or "horsing" around. Horsing about is a common cause for breaking anchor and dragging. There are three ways to moor.

Standard moor.
If you're to confront a strong reversing tide or wind, with little room to swing you will head into the prevailing wind/tide and drop anchor. Back down to double your intended scope, or where you want to drop the second anchor, and let go the second anchor. Motor back ahead to set the second anchor. When the wind or tide shifts to the opposite direction you will remain essentially where anchored originally.

Standard moor-storm conditions.
Determine the direction of predominant wind anticipated. Approximately one third of the scope to be employed should be used as a distance offset. With the bow pointed in the direction of predicted wind, motor a distance to starboard (port) off of your intended moored position line equal to the distance offset calculated. Drop your starboard (port) anchor and set it. It is helpful if this anchor is buoyed. Now motor ahead and to port (starboard) until you are the same distance offset to port (starboard) of your final moored position, and perpendicular to where the first anchor was dropped. Let go the port (starboard) anchor and set it. Adjust to an even scope. You will now be riding to two anchors, the rodes of which make a 90 degree angle which is bisected by your vessel and the predicted wind direction. Another-words, a line drawn between the two anchors will be perpendicular to the wind. You will minimize horsing by doing so. If time is of the essence and you've practised this moor, you can drop the first anchor and set it going ahead, veering off to drop the second, and then backing down on both. Note though that, you must get your full scope out on the first and, even then, particularly in a sailboat with line for rode, you risk fouling your prop.

The Hammerlock moor.
It may on occasion be found that a second anchor dropped to short scope, nearly up and down, will reduce horsing. It's usually better though to do a hammerlock moor, particularly when conditions are worsening and the vessel is already horsing around. The vessel will be sheering back and forth, and the second anchor should be dropped at the limit of the sheer to the opposite side of the deployed anchor. (you can drop to either side of the sheer but you may cross anchor rodes as you ride-on a boat this may be more fun to uncross later than what you wish) If your primary anchor is at 7:1 the second should be about 2-3:1. The second anchor may drag, which is OK as it's purpose is to stabilize the boat and prevent horsing which will break loose the primary anchor. In practise, it will grab and hold until the strain is such that it drags, sending some strain to the primary anchor, at which point it will usually reset and repeat as conditions warrant. This is a very secure method of mooring and many a hurricane in restricted waters has been ridden out moored in such fashion. If you're able to plan ahead for a hurricane or such you'll want to anchor so that the primary anchor takes the strain through the predicted wind shift and that the two anchors continue to offer an open 'V' by their rodes to the wind.

The hammerlock moor was originally discovered riding out a hurricane in the Chesapeake. It's original, and most effective, method of deployment is to cross the anchor rodes. If your bow chocks are so close together as to make the distance between them unappreciable there is nothing to be gained from doing so. On older ships, where the hawse pipes had great lateral offset, there was an advantage to crossing the rodes. On a boat a similar advantage can be realised if the boat lends itself to it, albeit at some cost to the topsides paint. If you're able to lead your rodes somewhat aft, to where the strain on each is angled off a fore and aft direction, crossing the rodes in the hammerlock will tend to move the center of strain aft and thus minimize horsing all the more. Another words, the pivot point is no longer at the stem but somewhere further aft.

It should be noted that a properly set anchor can still drag. (Huh?) You can even dive on your anchor and find her well set, but drag she might. The seabed is rarely homogeneous and it's quite possible that, even though you've anchored in sand, there might well be a decent sized rock (read, bolder) under the sand. As the wind comes up, and your anchor buries deeper under the strain, the anchor may come into contact with that rock and this may cause it to turn or twist. That might well result in the anchor tripping itself out and dragging. An anchor watch should be maintained. If you're completely comfortable you're either on anchor watch or you shouldn't be quite so comfortable.

The rest of that thread may be found here:
12-06-2008 09:33 AM
Boasun Did I say that there will be a lot of Opinions & suggestions? Yes I did!
Have fun sailing and as you have read from our other ship-mates, equipe your vessel with the proper anchoring gear.
Fair Winds and Following Seas
12-05-2008 07:49 PM
Valiente I think you did pretty well considering, particularly in being on deck, "ready, aye, ready", and with the engine running.

I think the Danforth reacted pretty much as it was going to in such a blow, and I agree with the assessment that it was a marginal choice of anchor for that situation. I consider the Danforth strictly a lunch hook and a convenience. They have their uses in tidal flows and Bahamian moor situations, as has been stated, because they grab well as long as there isn't much veer.

Given that is all you had, however, I would suggest that maybe the only way you might have improved the reset time would be through the use of a kedge sent down the rode on a messenger line. Not a lot of people these days (or in strictly fair-weather, coastal daysailing) would either know of or have a chance to practise this technique of getting the rode low.

Alternatively, knowing how these squalls tend to work, I might have considered motoring up to the anchor a little bit (which would be easy if there was a float on the anchor set pretty close to its depth) to take the strain off, or, if possible, simply hovering in place until the wind shifted and then dropping anchor. This would depend very much on whether the wind was coming down the creek "valley" or over the trees, as the windspeed affecting the top of the mast and the surface of the water might have been very different...i.e. you might have been able to "station keep".

But I don't have that information (creek width, depth, shoals, maneuver room), so I'll just say you did pretty well everything right except charter a boat from an owner who didn't have more than minimal ground tackle. Your realization that starting the engine and being on deck to check for chafe or thin water indicates a better level of preparedness than most charterers.
12-05-2008 05:13 PM
Originally Posted by noelex77 View Post
7:1 is OK for chain and rope, but more is better. Holding will increase up to something like double this. Did you include the height of the bow roller in the 7:1? How deep was the anchorage? (7:1 is OK for 40 feet, but very poor for 10 feet ) In short if you could have let out more scope safely with 40Knots forecast it would have been helpful...

...If your new wife is still speaking to you after this experience hang on her. A few flowers and some more “I love you” are needed.
Ha ha, yep she's still speaking to me, and can't wait to to find "our boat" (I introduced her to sailing a few years ago). After she took some lessons on her own a couple years ago, she said to me, "whatever happens between us, I'm going to keep sailing." Wow, that's cool.

As for the scope, I always include tide and freeboard in my calculations. I did let out a lot of rode, and it might have even been more than 7:1 (I was guessing because there were no markers on the line--I prefer markers). I agree more is better in these circumstances.

Originally Posted by JohnRPollard View Post
The overwhelming majority of thunderstorms arrive from the west (typically somewhere between SW and NW), so there's no real guesswork.
True, and point well-taken. I would still prefer to be using an anchor that deals with wind-shifts better. Though I realize that a Danforth, when set, is often the best holding in softer mud. I'll be looking at some of the newer anchors as a possible alternative, if the boat we end up with doesn't already have what we're looking for.
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