Photos of Anchors Setting

[noelex 77]

This was a Delta.

It was dropped by a private boat. They only stayed a few hours.
During their stay the wind was very variable giving us a chance to see their anchor rotating (photos to come).

They did not put much force on the anchor and the scope was once again short at only 3:1 in 4m of water.

The anchor like the Kobra managed to dig a little initially but then skipped out. It did not rotate upright and ended up with just the toe engaged.

How well will it cope with a change of wind direction?

[sneuman]

Spade, set in 10' of water at Abraham's Bay, Mayaguana.

[noelex 77]

Originally Posted by noelex 77

How well will it cope with a change of wind direction?

The answer is not well at all.

Anchors rotate well by remaining buried in the substrate and shuffling around to the new direction. Other than rotating they should fundamentally stay in same position as they swivel to the new direction. Anchors that are good at rotating that are set well in a reasonable substrate will always, or at least very nearly always, rotate like this.

The alternative situation of the anchor breaking out and resetting is much less reliable . A gust at the wrong time when the anchor is disengaged can cause the anchor to start moving rapidly and anchors find it difficult to start to dig into the seabed when moving at speed. There are addition risks such as the anchor encountering debris or the anchor moving into an area of unsuitable substrate.

If you want to sleep well at night your anchor must "shuffle".

As you can see, the Delta on this occasion did not manage to do this. Its fluke has disengaged completely from the seabed. Given time, it will probably reset in the new direction, but the reliability of this is much less than if the anchor had managed to keep the fluke at least reasonably buried while rotating.

Why did it rotate badly? The major factor was that its fluke was not sufficiently buried to start with. More scope and longer application of the initial setting force would have been a big help. Although, as you have seen, it is very hard to get the Delta well buried. The second factor is the anchor's ability to rotate well. In my view the Delta is considerably better in this regard than the fluke anchors (such as the Danforth and Fortress anchors), but it is a long way from the best designs.

An anchor's ability to rotate well is a vital property of a bower anchor and while there were some extenuating circumstances, this was a poor result.

Anyway enjoy the photos. It's tough to catch the moment of rotation like this on film:

[Panope]

Those last shots are great. If I flip through them fast enough, it almost looks like a video!

Steve

[sneuman]

Not to stray too much, but this question doesn't seem worth a whole new thread:

How much rode do folks typically pay out before backing down?

We usually pay out about a 3-to-1 scope, then back down and if everything seems good, pay out the rest -- minimum usually 7-to-1.

[Don C L]

Originally Posted by sneuman

Not to stray too much, but this question doesn't seem worth a whole new thread:

How much rode do folks typically pay out before backing down?

We usually pay out about a 3-to-1 scope, then back down and if everything seems good, pay out the rest -- minimum usually 7-to-1.

Judging from these recent photos, owners of Kobras and Deltas should probably have 10:1 out.

[sneuman]

Originally Posted by Don C L

Judging from these recent photos, owners of Kobras and Deltas should probably have 10:1 out.

For us, part of it is that we don't want to throw out a lot of heavy chain before we're sure we are going to stay. Overall, we've been quite happy with the Spade -- almost always sets on the first try. On the few occasions when it hasn't, we knew ahead of time that the holding was questionable.

We ended up spending an extra $300 for the Spade after discovering the Rocna would not fit in our bow-roller. I was all psyched for the Rocna, which I'm sure would have treated us just as well, but, alas, it wasn't to be.

[kas_1611]

Originally Posted by sneuman

Not to stray too much, but this question doesn't seem worth a whole new thread:

How much rode do folks typically pay out before backing down?

We usually pay out about a 3-to-1 scope, then back down and if everything seems good, pay out the rest -- minimum usually 7-to-1.

With our oversized 33kg Vulcan and 60m of 8mm G70 chain we usually start to back down once 2:1 is out and continue to lay out to 3:1 before the first check the anchor is holding. We'll then back down again, normally to about 1500rpm, and if it holds that it depends on weather or expected weather. If it is forecast to be light winds then we often stick at 3:1, if the wind is to pick up slightly then I'll let it out to 4+:1 and back down again, if we are expecting a hoolie then I'll let out 5:1 or more or enough to be able to tie up to shore with 2 stern lines. We have an additional 45m of 16mm Octoplait spliced to the chain so theoretically we can anchor at 5:1 in 18.5m of water (20m to bow roller)

Weather and depth permitting I'll also swim over and take a visual check on how the anchor is dug in. If it's well buried into the substrate, which it normally is, I sleep well all night.

It's a very valid question for this thread as it is about setting anchors and how much rode you let out does have a big impact on performance as Noelex et al have shown.

Keiron

[jongleur]

Holy crap! I'm appalled at how horrible
those convex anchors set, or don't. I've
got one of them, but not for long...

Re: Scope. I would think the better
procedure would be start with excess
scope and then after the anchor is set,
shorten back up. Can't understand the
other way around.

[sanibel sailor]

I have always used much greater scope on my CQR than is seen in this thread, minimum of 5-1 and more usually 8 or 10-1. I include height above water in my calculations. Of course I'm almost always in shallow water of 6-10 feet.
Just got a new mantus and will likely shorten scope in the future.

[noelex 77]

The theory is to lay the anchor rode out in nice straight line and not put any force on the anchor until the full scope is laid out. By setting the anchor at the greatest possible scope, the angle of chain at the anchor shank is shallowest and the anchor will set best.

There are a couple of potential problems with this:

• As you get to very long scopes the drag of the chain on the bottom diminishes the force on the anchor
  
  
• With very long scopes if there are any patches of chain that are not laid out nice and straight (and there generally will be) the drag of the chain will resist the straightening out of these areas. As the reverse force is increased the boat can suddenly jump back. This is not the nice progressive force you are ideally looking for.
  

The following is what I do. Let's assume I want to anchor at 5:1.

I drop the anchor. As the boat moves backwards I try to lay the chain out at the same speed. The aim is to introduce no force on the anchor, but no piles of chain on the bottom.
At about 3:1 I start to introduce some pressure by reducing the pay out speed of the chain. If I overdo this and there is a reasonable force on the anchor, it will start to dig in at these sort of scopes. The force will straighten out any loops of chain I have inadvertently laid.

Once the full scope is reached (in this case 5:1) we start to gradually apply significant force on the anchor ending in full reverse for 30 seconds (unless the wind is very strong).

The exception is if I want to anchor at a very long scope. Say 10:1. Here the points I made early in the post start to come into play and I think you might get a better set at a bit less scope, say around 7:1. If you want to play it safe (and if you are laying out 10:1 you are expecting a lot of wind), you can set at around 5:1 and repeat at around 10:1. I am not sure this makes a difference, but it makes me feel very secure .

Note:
The above is for anchoring in depths of around 5-10 m. At greater depths I would decrease the scope numbers slightly and vice versa at shallow depths.

This also assumes an excellent anchor. Don was joking with his 10:1 quip, but with anchors that don't do well on a short scope, try and increase the scope numbers if possible.

There is also some evidence that if you drop the anchor and let it "settle" in the substrate for a reasonable length of time before applying any force it will set better. I think this has some merit, but it is a difficult claim to evaluate. If you have trouble setting your anchor it is worth a try especially in softer substrates where some experienced hands claim it is essential.

There are also some special rules for specific anchor designs. Fluke anchors (such as Danforth and Fortress) in very soft substrates are better with an initial set at a short scope. This ensures the pivoting flukes open correctly. Shankless anchors like the XYZ are also supposed to set better at short scopes. These are exceptions that do not apply to most designs.

Finally:
The above is my recipe for the ideal drop. If you have a good anchor in a good substrate it will set fine almost no matter what you do. Anchoring is not rocket science, but dropping the anchor correctly is no harder than doing a poor job.

You never know we might be watching . My mermaid and I observe most anchor drops of boats around us.

[noelex 77]

This was the final result when the dust settled:

[Jim Cate]

Originally Posted by noelex 77

This was the final result when the dust settled:

Why, what could POSSIBLY go wrong???

Egads, I hope that you are upwind of this chap!

Jim

[double u]

I was puzzling for years what sort of "attitude" could be behind the casual approach to anchoring that we saw everywhere by a sizeable proportion of the cruisers, long or short distance ones. the only reason I could come up with is that everybody is leading such a protected, boring life full of every imaginable kind of safeguard that when finally "away from it all" they have to adopt a devil-may-care, risktaking attitude

[noelex 77]

This was a CQR copy, or sometimes called a plow anchor.

It was dropped by a private British boat that stayed overnight. It was very difficult to see the setting mark. This was partially because there was a previous boat's setting mark right next to the anchor confusing things somewhat, but I think it dug in moderately quickly, which I very rarely see from a CQR copy or even a genuine CQR.

It is still on its side with the flukes only partially buried, but on this occasion it does look to me that there is some possibility that with a bit more setting force the anchor could dig in more and rotate upright.