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Discussion Starter · #1 ·
Can anyone help with some anchor tips? We tried to anchor for the first time today in an empty cove to row to a beach. Dave took all but the baby with him in the dinghy. The baby and I stayed on the boat so I could try to get her to nap and do some fishing. Dave thought the anchor was good but it wasn't and we kept drifting to shallower water.

Any tips on how to set this kind of anchor?
 

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Old soul
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OK, here's the general approach to proper anchoring. I can't tell from your description what you did, but perhaps this will help.

As you are aware, anchors only hold by digging into the substrate (the bottom). To do this you need an appropriate anchor for the type of bottom, and the size of boat. You also need an anchor rode that allows you to pull as horizontally as you can. AND you need to set the anchor properly.

No anchor works well for all bottoms, although some work in a wider range of bottoms than others. I'm assuming the anchor you used is the danforth hanging from your pulpit. This anchor works best in sand, thicker mud, and clay (but not dense-solid clay). It works poorly in hard or dense bottoms like gravel, rock or hard clay. It is also a poor choice in weedy areas or really soft bottoms.

Assuming you've got the right anchor for the right conditions, you then need a rode to produce that horizontal pull. This is a combination of length and weight. Chain is used to keep the rode horizontally straight. At minimum your rode should include your boat length in chain, and more is generally better. Most cruisers use all-chain rode. In general you want a 5 to 1 ratio of rode length vs depth of anchor, but more is better. So if your anchor is 10' down, you need to lay out at least 50' of rode. Remember, depth of anchor includes the distance from your bow roller or chocks to the bottom. I'm estimating your boat has a 3-4 foot rise at the bow, so this needs to be added to the water depth.

Once you've got all your gear in place, and you've picked an appropriate spot, you need to lower the anchor (not drop it) and drifting downwind (or gently motoring backwards) lay out your rode. Once you've laid out your expected rode you can begin digging in the anchor (setting it) by cleating the rode and putting some force on the anchor. Do this gently at first, and if it slips at all, let out more rode. As you feel the anchor start to hold, gently build the reverse force with the engine. If it slips at all, ease off and lay out more rode. If you can't get it to hold, or if you've run out of swing room, pull in the anchor and try again.

Anchoring is a skill, just like the rest of sailing. It takes time to do it right, and practice to enhance your skills. Hope this helps.
 

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Master Mariner
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I would suggest you pick up a copy of Royce's Sailing Illustrated. It is a fun, informative little book with a wealth of information on how best to have fun, without a lot of problems, on your boat.
 

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first sailed january 2008
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I dont know what to add that mike didnt say. Why dont you tell us how much chain and or rope you let out and how you went about the anchoring process and we can tell you what you did wrong. Also tell us the conditions, how much wind, your location.

Its very possible as well that you did noting wrong, that the anchor just didnt set well and was dragging.

Just make sure you put the boat in reverse and lower it slowly while moving backwards. Maybe at a speed of about .5-1 mph. So lower it until you feel it touch, then reverse while letting out rope. When you have about 3:1 or 5:1 depending on depth, cleat it off and reverse harder. About 1/2 throttle. You should feel the rope rubber band and then you'll notice you're not moving. Once you let off the engine you will probably even drift forward.
 

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everything above is correct I would just add that you should use some chain on your anchor on small boats at least as much chain as the boat is long ie 5m boat 5m chain this will help your anchor bite in as it will pull from a better angle.good luck
 

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The chain also has a lot of weight, which keep the angle of pull, caternary angle, lower. It keeps the anchor on the sea bottom better.
Apparently this really isn't true.

We can therefore conclude that the majority of typical rode set-ups lose most of their benefit provided by catenary well before the anchor is likely to be anywhere near its limits. Beyond this point (once the rode is effectively straightened), the weight of the chain makes no difference to the ability of the anchor to hold the boat.

In 40-50 knots of wind and a little surge, this 12 mm G40 chain is bar taut, with no catenary visible even looking down the line of the rode.

The practical upshot to this as it will interest most boaters is that the lore of heavy chain is demonstrably false as it applies to small boats and modern anchors. Chain is still necessary for a number of other reasons, but it need not be unnecessarily heavy. It follows that high strength chains may be utilized to offer the same functionality for less weight – as such, high tensile grades are recommended en lieu of G40 / high-test, and it is suggested that weak low grades such as G30 / BBB are avoided altogether.
http://www.petersmith.net.nz/boat-anchors/catenary.php
 

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Old soul
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Apparently this really isn't true.
There is endless debate about anchoring... But to be clear, what Smith is questioning is the ultimate holding benefit of chain. What I and others are suggesting is that a length of chain helps SET the anchor properly. Two different things.

I'll say again, the key to anchoring is getting a good set. To set an anchor you want as horizontal a pull as possible. A weighted rode (chain) combined with a long rode are the best ways for most cruisers to achieve this horizontal force.

BTW, Smith is the original maker of the Rocna. I am a big supporter of these new-style anchors. In fact, I switched my bower to a Rocna-25 (25kg, 55#) a few years ago, and absolutely love it. The evidence, and my experience, is that these anchors operate in a wider range of bottoms than the older plow-style anchors. They set and re-set easier, and may have (this is endlessly debated) more ultimate holding strength.

My general recommendation for effective normal anchoring is for to get the largest new-style anchor you and your boat can reasonably manage, along with as much chain as you can manage. By reasonable I mean you want an anchor system that is large, but not too heavy for the boat and crew. It must be one that you can easily deploy and retrieve. If it's too big, this may dissuade you from re-trying (and re-trying, and re-trying). Remember, it's mostly about getting the best set.

BTW, any of the new anchors would likely be as good: Rocna, Manson, Spade, Mantus ... probably a few others I'm forgetting.
 

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Excellent post Mike and Mr F's link to the data on anchoring will provide me with hours of amusement as I sit at anchor!

The one point I would add is that we never 'anchor and run'. We set the anchor and then take a break watching out position and then after an hour we put load on the anchor again just to make sure we are really set.

The original poster's bog shows a family with children (all in life jackets) having lots of fun with their boat...I wish them many years of happy sailing.

Phil
 

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We'll done, Mike.

I will add an intermediate step I find useful. I first let out 2x the depth of the anchor (properly defined as water depth plus the height of your bow). In the wind, the bow is likely to fall off to one side or the other, as you're letting it out, so I wait for the bow to come back into the wind. This tells me that the anchor chain/rode is essential straight off the bow to the anchor. I may apply a touch of idle reverse just to begin to properly align the anchor. It may have fallen on its side or even be upside down, depending on design. This little maneuver will not set the anchor, just hopefully flip it. Then I let out another 2x, then more idle reverse after she points back into the wind again. Then the final 2x to 3x. This should put out 6 to 7 scope in total. At this point, I apply slowly increasing rpm in reverse. Don't ham fist it, you want it to set in.

If you have SOG on your GPS, it's very useful for determining set. In theory, it should go to zero, even though you are in gear. In practice, it often stops at 1kt or so, as any swing side to side is picked up as SOG. At the least, you should see it drop and stay steady. Take a bearing to shore as well and double check.

The old wives tale that has been dispelled is that rode requires 7-1, while all chain only requires 5-1. In a real blow, as noted above, you still need scope to hold. Chain is still better, prior to enough wind to straighten it out, but if I'm sleeping at anchor, I do not want to think about it. I'm typing at anchor right now and have 8-1 out. Slept like a baby.

Finally, the newest anchor designs, commonly referred to as NextGen anchors, really do seem to set and hold better in the widest conditions. Examples are Rocna, Mantus and Manson Supreme. If you are using that Danforth, they can be tough.

Remember, it's not practice that makes perfect, it's perfect practice that makes perfect. Do it all every time. Good luck.
 

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Mermaid Hunter
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In general you want a 5 to 1 ratio of rode length vs depth of anchor, but more is better.
Buried in Minnewaska's post is an important point. Scope (5:1, 3:1, 7:1) is measured from the bow roller to the bottom, NOT depth of water.

Otherwise Mike's guidance is good.

Apparently this really isn't true.
Correct. In almost all cases the value of chain is chafe resistance and ease of integration with windlass gypsies.
 

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Mike's description of how to set an anchor is excellent. I don't see how I could add anything of significance.

One thing I did note from your posted picture is the anchor is an inexpensive Danforth knockoff. The "loop" shank is supposed to aid in retrieval, but all it does it make it more prone to pulling out if the wind shifts. Probably OK for a short stop in good conditons, but not something I would want for an overnight or in any kind of weather. I would plan on getting a better anchor if you plan on doing any cruising.
 

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Old soul
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Buried in Minnewaska's post is an important point. Scope (5:1, 3:1, 7:1) is measured from the bow roller to the bottom, NOT depth of water. Otherwise Mike's guidance is good.
Just for the record Auspicious, that's what I thought I wrote, or intended to ... perhaps not as clearly as Minn's post.

BTW, I like Minnewaska nuanced additions. In reality we will start to dig in the anchor once about 2/3rd of our expected rode is out, but it is a gradual and gentle process, tailored to each anchoring experience. And I always put out lots of rode. The more, the merrier. I'd rather spend more time in the morning hauling up, than dealing with any overnight alternative ;).

One thing I never see mentioned is the use of tactile feel when setting the anchor. I put a hand on the rode and feel what the anchor is doing. If it's bouncing along it's easy to tell. If it's grabbing and slipping, again easy tell. If its holding I can feel it faster than I can see it. Not everyone can get a hold of their rode, but if you can, I suggest learning how it feels through the process.
 

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Discussion Starter · #15 ·
Thanks for all the replies. Yes we are using the Danforth that is in the pic in the original post. Its the anchor that came with the boat when we purchased it this winter.

Since Dave is the one that was anchoring, I can't say for sure what he did, but I can say for sure, it wasn't what Mike has suggested, lol... We were in about 9-10 ft of water, the depth meter kept fluctuating depending on how we drifted. After reading Mikes post, Dave said we don't have enough chain on it and that he didn't let out nearly enough rope.

He had tried setting it a couple times and the last time he had thought it set, and it did for about 20 min before we started drifting. When we brought up the anchor it was covered in seaweed, so I'm sure that didn't help.

Thanks for all the advice. I think we will be looking for a better anchor.
 

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Mermaid Hunter
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When we brought up the anchor it was covered in seaweed, so I'm sure that didn't help.
That is a common problem with fluke type anchors like yours. They get bound up in the vegetation and you think you are set until wind or current picks up. Then the weed pulls out and you are drifting.

Give your anchor time to settle (5 minutes or so is plenty) and then back down. Ease the power up by stages in reverse but there is no reason NOT to use full power. You can't possible match the load of a windy day. If it won't hold under full power reverse it won't hold in a summer afternoon thunderstorm.

If you are going to replace your anchor, which I would recommend, get any of the new generation scoop anchors (Rocna, Manson Supreme, Spade). The performance is hugely better in nearly all bottoms than any older design anchors.
 

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Swab
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Excellent post Mike and Mr F's link to the data on anchoring will provide me with hours of amusement as I sit at anchor!

The one point I would add is that we never 'anchor and run'. We set the anchor and then take a break watching out position and then after an hour we put load on the anchor again just to make sure we are really set.

The original poster's bog shows a family with children (all in life jackets) having lots of fun with their boat...I wish them many years of happy sailing.

Phil
Plus one, and thanks to Mike for a very clear description of the anchoring process.

My $.02: With a modern anchor appropriate to the bottom conditions, use enough chain to provide some catenary and avoid chafe from the seabed, coral, rocks etc. (30-50 feet of chain works for us). Use enough rode to allow a minimum of 5:1 scope and more in heavy conditions. Lower the gear to the bottom under control and back down on it to set the hook. Do not simply dump it all overboard and pop open a beer.
 

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Bristol 45.5 - AiniA
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A general comment from the situation here. We have a tendency to use words like Danforth, Bruce, and CQR when we should be saying Danforth-style, Bruce-style, CQR-style. Once these older anchors lost their patent protection it was an open market for copies that were in some, or many, ways similar to the originals. Often the copies were not as strongly built or did not get the angle of penetration right. I certainly think that it is a rare copy that comes close to the quality of the original. Having said that I am a big fan or the newer style anchors though.
 
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Over Hill Sailing Club
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Mike's comment on feeling the rode to tell what the anchor is doing is a good one. One of the things I don't like about all chain is that it is much more difficult to tell, by hand, what the anchor is doing because of the catenary. With rope rode you can tell immediately.

To me the most important part of choosing any anchor type is to make sure it is MUCH bigger than the size listed in the manufacturers specs. Overkill is a good thing when it comes to anchors. If a 25# anchor is listed for your boat size, get the 40# model:) Weight rules.
 

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I'm shocked everyone keeps enabling these two when they have no idea what they are doing, with a baby on-board no less.

The single most important thing when anchoring, IMHO, is the bottom you are on and scope and they clearly had no idea about either :eek:

I bet you they had 15 ft of line out in 10 feet of water, not 50, 75 or even a hundred...

You're lucky you did not drift a ground
 
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