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Old 20-03-2013, 23:01   #76
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Re: What happened to Bruce almighty?

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Originally Posted by Andrew Troup View Post
Given that the shorelines prevent the boat from circling and tangling the rodes on multiple anchors (the usual objection) it makes perfect sense to me to lay the main anchor in the direction of the strongest gusts, and kedge(s) in the direction of side wind(s). If these winds are strong, it may pay to lead the shorelines to the chainplates rather than the quarters, to allow the boat to weathercock to these gusts from the side, further reducing the loads.
When stern tied with a crosswind (which you nearly always get) the forces on the anchor can be considerable. It's is a force in very steady direction and the anchor is usually being pulled "uphill" which helps holding considerably, but the rocks are only a few feet behind the boat so you need faith in your ground tackle.
Laying out anchor towards the wind direction helps considerably and its an option worth considering.

The biggest problem with this is in much of the world its just not possible. Another boat will want to use the same space. There are enough crossed and tangled anchors when everyone is lying to single anchor directly in front of them.

If you have good big anchor this is no problem, if you are relying on setting two anchors to ease the strain you will be out of luck.

If you have got a good big anchor that you have confidence in why would you bother (at least most of the time) going to the trouble of setting a second anchor? That can impinge on your time watching the sun go down with a nice bottle of red. (Something, in my experience, most Kiwis take very seriously )

Two anchors also hampers your ability to leave quickly in an emergency. Shore lines can be cut, but that is expensive to do with anchors unless you are guaranteed you can retrieve them later.

BTW blowing an un-forecast 40k here at the moment, the best news is that it gets me out of varnishing because we are bouncing around too much.
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Old 20-03-2013, 23:41   #77
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Re: What happened to Bruce almighty?

Well, Nick, there's only two ways I could apply your advice.

To carry a single anchor that would cope with 99% of my anchoring situations,
Either
a) I would have to settle for an anchor almost as big as yours, on a much smaller boat,
or
b) I would have to restrict the places I anchor,
and implicitly the places I sail*

or some compromise between the two.
And naturally I don't find any of the above even slightly palatable.

* some of them have only a couple of anchorages, often only one viable at any one time. And the nearest alternative may be many hundreds of miles away.

- - - - -

But lets stick with a less "off the beaten track" situation, more familiar to more people.

Let's say each of us has backed up to an identical small cove facing the wind (big enough for only one boat, Noelex ;-), laid the big anchor, and taken lines ashore. The anchor is well dug in to soft mud. Next day we start getting strong gusts from the starboard beam (predominant wind still on the bow). I would row an anchor out to starboard.

You would bring the starboard sternline forward.
(So would I)

But the angle between your main rode and the sternline might still be 140 degrees, with the wind bisecting that angle, whereas my kedge rode is 70 degrees off the bow, directly upwind.

You sag off to leeward as your big anchor creeps through the soft mud, because it's seeing a load increased by 50% due to the unfavourable angles, even if there's enough room that the boat can be allowed to swing entirely head to wind, much more if not.

My kedge in this situation is a Fortress, ideally suited to this situation: easy to lay, holds well in soft mud. Even if it does creep for a while, provided it was on a long initial scope, I can just take up on the rode until it's dug deep enough to hold.
As there is no longer sufficient swinging room, you say "This cove is unsuitable because I cannot lie to one anchor; I will find another", sailing off into the tempest while I stay comfortably put and start another bottle of red - ooops - book.

At this point, my friend, it seems to me you are letting your dogma dictate where you can anchor, although hopefully not where you can sail ...

... however it does strike me that if a windlass malfunction, bow roller damage, or or problem with a single anchor constitutes, for you, an "emergency", then I can see there would be some incentive to stick to 'milk run' waters.
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Old 21-03-2013, 00:12   #78
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Re: What happened to Bruce almighty?

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You sag off to leeward as your big anchor creeps through the soft mud, because it's seeing a load increased by 50% due to the unfavourable angles, even if there's enough room that the boat can be allowed to swing entirely head to wind, much more if not.
.
Get a big bigger anchor.

If your anchor is dragging under anything other than extremely unusual circumstances it needs to bigger. This is underlying principle of the "single anchor brigade".
This saves the need to row out a second anchor as you describe (and presumably a third anchor when the wind changes direction) all for an extra 20Kg.
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Old 21-03-2013, 00:14   #79
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Re: What happened to Bruce almighty?

Noelex: good point about leaving in a hurry (and SnowPetrel makes the equally good point in another thread that all-chain is undesirable on a second anchor, in cases where there is nothing stopping the boat circling the anchor)

I prefer to use floating rope rodes on a kedge, stowed on a plastic yo-yo reel, which I fill with foam so it makes an anchor buoy. All you have to do to bugger off in a hurry is throw a clove hitch around the drum and chuck the whole thing over the wall.

I have individual links of medium-large stud-link condemned fishing-boat chain (gritblasted, sanded smooth around one end, and galved) which I can cow-hitch at suitable intervals to a floating line if it needs to be sunk for tactical reasons.
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Old 21-03-2013, 00:19   #80
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Re: What happened to Bruce almighty?

Noelex: Re your "get a bigger anchor"

(sigh..>) I'm not interested in carrying a 45kg anchor on a 7500kg boat, which is what it would take to do what you suggest, with possibly a 100% overload in soft mud. (due to the unfavourable resultant vector and being held partly side-on)

Someone wiser than me wrote above:
"When stern tied with a crosswind (which you nearly always get) the forces on the anchor can be considerable. It's is a force in very steady direction and the anchor is usually being pulled "uphill" which helps holding considerably, but the rocks are only a few feet behind the boat so you need faith in your ground tackle.
Laying out anchor towards the wind direction helps considerably and its an option worth considering."

Perhaps you missed this post?
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Old 21-03-2013, 00:25   #81
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Re: What happened to Bruce almighty?

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Get a big bigger anchor.

If your anchor is dragging under anything other than extremely unusual circumstances it needs to bigger. This is underlying principle of the "single anchor brigade".
Yes, and it works for them, I've never suggested otherwise.

The trouble is, what is extremely unusual for some is not particularly unusual for others. And there is a limit to how big is practicable.

I've now exhausted every way I can think of get these two points across.

Thanks for the discussion, everyone.
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Old 21-03-2013, 00:27   #82
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Re: What happened to Bruce almighty?

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Someone wiser than me wrote above:
"When stern tied with a crosswind (which you nearly always get) the forces on the anchor can be considerable. It's is a force in very steady direction and the anchor is usually being pulled "uphill" which helps holding considerably, but the rocks are only a few feet behind the boat so you need faith in your ground tackle.
Laying out anchor towards the wind direction helps considerably and its an option worth considering."

Perhaps you missed this post?
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Old 21-03-2013, 00:41   #83
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Re: What happened to Bruce almighty?

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I've now exhausted every way I can think of get these two points across.

Thanks for the discussion, everyone.
You were "tag teamed" by Nick and myself, which is a bit unfair, but hopeful others found the two alternative points of view useful.
Somehow I don't think we are going to change each others anchoring philosophy.

If we ever share an anchorage you are welcome on board for a drink. After rowing out all those anchors you will need it
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Old 21-03-2013, 03:25   #84
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You were "tag teamed" by Nick and myself, which is a bit unfair, but hopeful others found the two alternative points of view useful.
Somehow I don't think we are going to change each others anchoring philosophy.

If we ever share an anchorage you are welcome on board for a drink. After rowing out all those anchors you will need it
Same here and I really hope you will be the exception to my 99% rule and thus not end up in trouble... I've seen some before, but not many
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Old 21-03-2013, 21:19   #85
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Re: What happened to Bruce almighty?

Thanks for that, guys: I'm sure our boats would be three of the least likely to drag in any anchorage, regardless of the amount of convivial drinks we imbibed together.

I also think our practice would probably be a lot more similar than our philosophies would suggest, if we were anchoring in the same circumstances.

I'm perfectly happy with "one big anchor" as an aspirational goal, I just have a few qualms with it as a universal prescription for practice.
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Old 22-03-2013, 06:27   #86
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Re: What happened to Bruce almighty?

i am and have been sitting nicely in this 1-2 meter swell since december on a beautiful 30 kg original bruce anchor.
i re anchored but i am quite happy with this anchor and its performance in this rocky bottom and swell situation. endured a lightning storm here in december with no problem.
the only problem i have found with my set up is the jerks in the power boats who have no sense of how to and where to anchor--anchored down 80 ft from my anchor when i have 160 ft of chain out--kinda befouled my swinging room and doesnt even know what he did despite being advised--is a true jerk. but life is good and he will leave before i do
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Old 22-03-2013, 06:38   #87
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Re: What happened to Bruce almighty?

In 35 years of anchoring the only anchor that I have ever had drag on me was a Bruce.
IMHO the new gen anchors are a vast improvement over the older designs including Bruce, CQR, and Danforth.
I currently use a Rocna as primary and carry a Delta and a Fortress for back-up.
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Old 22-03-2013, 06:43   #88
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Re: What happened to Bruce almighty?

Back to the original topic. Now that original Bruce anchors must be getting somewhat scarce and/or worn out, and apparently nobody is building exact replicas, what anchors will those who are Bruce fans purchase? The Manson Ray seems to be one of the better claw designs in terms of dimensions and build quality. Are there others?
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Old 22-03-2013, 07:00   #89
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Re: What happened to Bruce almighty?

i am still looking for 2-3 more original bruce anchors, 30 kg each.
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Old 22-03-2013, 19:12   #90
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Re: What happened to Bruce almighty?

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Back to the original topic. Now that original Bruce anchors must be getting somewhat scarce and/or worn out, and apparently nobody is building exact replicas, what anchors will those who are Bruce fans purchase? The Manson Ray seems to be one of the better claw designs in terms of dimensions and build quality. Are there others?
Prof Knox, in the PBO article you linked to on the Knox anchor thread, tested an Atlantic knockoff which performed according to his methodology (at zero angle/infinite scope !) better than a genuine Bruce.

I personally have grave reservations about the practical applicability of this test series because of the unrealistic scope: it may be that the fluke geometry which works at regular and short scopes is actually a disadvantage at infinite scope.
Otherwise you'd think an anchor with all the advantages of a Bruce, but with 50% better holding, would be selling absolute gangbusters in places like Ushuaia and Bluff, given the unavailability of the genuine article.

I also have reservations about testing (as he did) in the intertidal zone: my tests, and experiences with trying to set stern anchors, have suggested to me that ground which is permanently underwater has quite different holding characteristics than the same ground which dries intermittently.

This also seems to make theoretical sense, which is always a consolation, even if often misleading. Apart from the obvious propensity to harden of drying bottom, there's also the fact that the wind will blow away fines in a way which cannot happen underwater. Furthermore, the flora and fauna which grow intertidally differ markedly from submarine species.

Certainly his other tests, above the tideline, I consider to be absolutely misleading and contrary to experience (along with such tests which seem to form a major part of the design of many if not most new-Gen anchors).

Try for yourself, setting two identical anchors: one ashore on the beach, and one offshore. Once they're well dug in, grind in the bow anchor on the windlass.
Despite the unfavourable scope* for the offshore anchor for reasons of simple geometry, I'm confident you'll find it's the beach anchor which drags, provided the offshore anchor is also in sand. (Rig a buoy from the offshore anchor, and drop a sinker alongside with a small buoy as a datum mark)

* I'm assuming you're testing new gen anchors, not genuine Bruces - who has two identical genuine Bruces these days! (otherwise I'd be contradicting myself on zero scope being favourable ;-)

Finally I'm sure Prof Knox would admit, if testifying as an expert witness, that it is dangerous to generalise from tests carried out in a single environment.
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