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Old 11-10-2011, 08:10   #91
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Re: A Second Wind for Rocna

Quote:
Originally Posted by Dockhead View Post
Indeed, Fortress is an interesting case. I had a long offline discussion with the guy who sells them in Florida. He argues passionately that the Fortress is not just the ideal kedge (as most of us use them), but is also perfectly suitable as a main bower.

I always heard that they break out in a tide or wind shift; so never sleep to them. And so I never have. But I have used them as kedges for decades -- they are incomparably good in that role. Easy to handle, and bite like a piranah.

I wonder if anyone actually uses them as a bower?
The Coast Guard does, and I have seen a few boats at our marina with them as main.
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Old 11-10-2011, 08:19   #92
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Re: A Second Wind for Rocna

A couple of definitions to illuminate the discussion:

Anchor:
1) Any of a number of heavy or light, hook or other shaped devices, that is dropped over the side of the boat, on the end of a length of rope and/or chain, and which is designed to hold a vessel securely in place until:
a) the wind exceeds 2 knots
b) the owner and crew depart
c) 3 a.m.
2.) A device designed to bring up mud samples from the bottom at inopportune or unexpected times.
3). The thing rotting in the bilge of every racing yacht (unseen).

Anchor light:
A small light, not bright enough to be seen, used to discharge the battery before daylight.
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Old 11-10-2011, 08:52   #93
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Re: A Second Wind for Rocna

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Don't tell that to Fortress. You have seen their marketing slogan, right?

Google this: the world's best anchor

What do you think about that claim Delf?
We'd call that "puffing." A broad statment that no reasonable person would mistake for fact. Rather like BMW, the "ultimate driving machine." Fortress may be the best kedge. Rocna may be the best all-around, but there is some very strong company and there is always bottom variability to consider.

The way I see it, Rocna makes a good product, but their days of comanding a premium price based upon invincibility of integrety, engineering, and knowledge are past. They need to compete on price with Delta, Spade, and Manson. That's is what over-puffing can get you.
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Old 11-10-2011, 09:45   #94
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Re: A Second Wind for Rocna

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We'd call that "puffing." A broad statment that no reasonable person would mistake for fact. Rather like BMW, the "ultimate driving machine." Fortress may be the best kedge. Rocna may be the best all-around, but there is some very strong company and there is always bottom variability to consider.
I agree. It's just marketing language. But, under "angry mob scrutiny", some might try to call it "lying". As I said in the thread over on SN, you just have to be careful when you set out to crucify someone based on pure "integrity and ethics"...especially when it comes to marketing claims. Lots of dirty hands out there.

Quote:
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The way I see it, Rocna makes a good product, but their days of comanding a premium price based upon invincibility of integrety, engineering, and knowledge are past. They need to compete on price with Delta, Spade, and Manson. That's is what over-puffing can get you.
I think you absolutely nailed the heart of the issue. Apart from the apparent global disdain for Craig's demeanor and communications skillz, and the apparent corporate dishonesty about the specs, it's really more about the price (i.e. - "premium") than anything. The refrain always comes back to..."Why would you pay more for a Rocna, when..."

I could almost guarantee that if CMP came out with Rocnas that were a fair bit below the price of a Manson Supreme, you'd see a stampede back to that anchor - with all the technical minutiae, and even past ethical sins, becoming meaningless. Price seems to always rule the day - at least here in the US.

Walmart has been pretty successful with this approach. "Rollback Rocna" anyone?
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Old 11-10-2011, 09:56   #95
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Re: A Second Wind for Rocna

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Originally Posted by Delfin View Post
The Coast Guard does (*use a Fortress or similar Danforth-style anchor as a bower*), and I have seen a few boats at our marina with them as main.
The USCG application isn't relevant. When the Coast Guard anchors they maintain an anchor watch around the clock.
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Old 11-10-2011, 12:04   #96
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Re: A Second Wind for Rocna

Quote:
Originally Posted by cat man do View Post
Quote:
Originally Posted by Bash View Post
Nooooooooooooooooo!

Lol, never even occured to me to do something so rdical as to look "doh!" and thanks :-)


re the fortress,
My problem with the fortress is that the entire weight is dependent on a single 1/4-20 (or smaller) screw and nylock nut that holds the whole thing together. My experience with stainless screws in Aluminium doesn't give me a warm fuzzy feeling about that design.
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Old 11-10-2011, 12:27   #97
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Re: A Second Wind for Rocna

Quote:
Originally Posted by thinwater View Post
We'd call that "puffing." A broad statment that no reasonable person would mistake for fact.
All taken from the company websites:

Spade: "The world's most reliable anchor."
Fortress: "The world's best anchors."
Manson: "The finest stainless steel and galvanized anchors made."
Ultra: "The quickest setting and highest holding anchor in its class."
Rocna: "Rock solid."

I wonder why they call it "puffing?"
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Old 11-10-2011, 12:52   #98
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Re: A Second Wind for Rocna

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Originally Posted by xymotic View Post

re the fortress,
My problem with the fortress is that the entire weight is dependent on a single 1/4-20 (or smaller) screw and nylock nut that holds the whole thing together. My experience with stainless screws in Aluminium doesn't give me a warm fuzzy feeling about that design.
I think you'll find the screws are not load bearing; more like a cotter to keep things from rattling apart. I've not heard of any failures there. I've had some old Fortress anchors, too.
Fortress Anchors - Assembling Your Anchor

I would worry about thing that actually fail, like chafe, poor sets, and old shackles. It's not about "warm fuzzys", it's about statistics.
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Old 11-10-2011, 12:55   #99
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Re: A Second Wind for Rocna

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I would worry about thing that actually fail, like chafe, poor sets, and old shackles. It's not about "warm fuzzys", it's about statistics.
I agree, however I also trust my gut. With regard to anchors mine are a solid chunk of steel that is bigger than the 'recommended' size. Obviously Fortress has their own view, and I don't begrudge them that, I just don't agree with it.
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Old 11-10-2011, 13:53   #100
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Re: A Second Wind for Rocna

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I agree, however I also trust my gut.
OK, caveman. Let's go with 100,000 years of evolution-based guidance . Sorry, I had to say it. As an engineer, I've seen a lot of scary gut-based designs. I prefer numbers and expereince.

Actually, I agree. Fortress is a great one-direction design, and regardless what Fortress says, I know from expereince that it comes out very easily when the wind changes. Their multi-dirrectional claims, in my understanding, are based upon an anchor that is deeply power set with real horsepower, which must sailboats lack.
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Old 11-10-2011, 13:54   #101
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Re: A Second Wind for Rocna

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Originally Posted by Bash View Post
All taken from the company websites:

Spade: "The world's most reliable anchor."
Fortress: "The world's best anchors."
Manson: "The finest stainless steel and galvanized anchors made."
Ultra: "The quickest setting and highest holding anchor in its class."
Rocna: "Rock solid."

I wonder why they call it "puffing?"
+1. So could the metallurgists/engineers in the crowd run some numbers on all these and see who's "telling the truth, the whole truth, and nothing but the truth"?
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Old 11-10-2011, 15:12   #102
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Re: A Second Wind for Rocna

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Wow, I love these anchor threads!

I just wanted to jump in here and maybe help clear up some of the terms that are being used. For those without an engineering background, they all may sound more or less the same. Hope it helps (Wiki is your friend).

Yield Strength: The lowest stress that produces a permanent deformation in a material. In some materials, like aluminium alloys, the point of yielding is difficult to identify, thus it is usually defined as the stress required to cause 0.2% plastic strain. This is called a 0.2% proof stress.

This not to be confused with Tensile Strength.

Tensile Strength: The limit state of tensile stress that leads to tensile failure in the manner of ductile failure (yield as the first stage of that failure, some hardening in the second stage and breakage after a possible "neck" formation) or brittle failure (sudden breaking in two or more pieces at a low stress state). Tensile strength can be quoted as either true stress or engineering stress.

These values are given in MPa, which is force over an area (think flat 20c coin). Yield Strength is the first value to be observed, as this is the initial point where there is permanent deformation, but not fracture. To put it simply, this is the point where the object (think steel bar) will no longer spring back to its original shape, but is nowhere near breaking. Then the second point measured is Tensile Strength, where the object will suffer fracture (think pulling on a carrot until it breaks) 'Normal steel' has a very long yield plateau before fracture, whereas other metals will yield, then fracture almost simultaneously.

So the two terms are not mutually exclusive, as one precedes the other.

Notice that there is no mention of bending. Any bending moment (think lever arm like socket rachet) is referred to in kN/m, not in MPa. Resistance to bending is a function of the section size/shape and material properties (steel, aluminium etc).

Does any of that makes sense?

Cheers,

Bloke
Some of it but we don't have 20c coins so I have no idea of the size so I can't figure out that pressure.

And I pulled on a carrot and could not break it. I bent it sideways and it broke easily. This is like the Rocna right?

PS.

Thanks for joining the fun.
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Old 11-10-2011, 15:21   #103
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Re: A Second Wind for Rocna

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Yup.

If you read the PBO test carefully, you will note (in a sidebar labeled 'normalization') they had a large variation (+-40%) in results between pulls (not surprising because the bottom is inconsistent), which they then aggravated by their 'normalization procedure (dividing the results of one single pull by the result of another) so that their ending efficiency measure has a statistical confidence interval of about +-80%!

The magazine made the careful and correct (but not to startling) conclusion that for holding in medium hard sand the anchors could be divided into three groups: 'excellent' spade, manson and rocna; 'good' delta, and 'poor' cqr and bruce. Given the very high measurement variation no more precise conclusion/statement than that could/should be made from the data.

It should also be noted that these tests were done at 'infinite' scope, which obscures the important fact that some designs perform better than others at actual real world scope. And that relatively small anchors were tested and there are different scaling effects.

I have personally talked with the people who conducted most of the recent anchor tests and most believe the actual performance of the manson and rocna are indistinguishable (not surprising given the very similar designs) and the spade is somewhat different (better in some situations and worse in others) but in the same overall category.

As many of you know, my personal opinion is that ultimate holding power per lb in medium sand is not the single most important criteria by which to judge/select an anchor - it just happens to be the easiest to test. How many of you pick your car by max straight line speed per lb?

Probably the best statement so far.

I certainly have figured that

Quote:
the anchors could be divided into three groups: 'excellent' spade, manson and rocna; 'good' delta, and 'poor' cqr and bruce.
was true over my years.

But I thought the Bruce was better since I had (and still have) one of the earliest (1982) small ones.
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Old 21-10-2011, 18:14   #104
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Re: A Second Wind for Rocna

I was sent a copy of the below e-mails, because I was mentioned, and asked to comment.

I have highlighted a couple points:

#1 they are providing special 'tuned anchors' for anchor testing.
#2 They acknowledge that "the Chinese (ROCNA) anchors that you are shipping are NOT to spec, and we have yet to see one that is acceptable"
#3 They have had some poor test results and some consumer complaints about the anchor holding.
Edit: delete this point #4

Regarding the comment about my little anchor test: that it was only on a frozen beach - its inaccurate. As I clearly stated results from testing in multiple bottoms. I 'bench' tested in two different bottom conditions, which were typical of the high/mid latitude conditions (one was rocks over hard sand, the second was soft mud). The first was the bottom they did not like. But if you look at the photos it is clear that the anchors are setting just fine in the sand - its just quite stiff as is true in many hard sandy bottoms. The second was in fact quite the opposite - a very loose and not at all stiff or frozen mud. And then we did parallel tests in 15 real world anchorages with a wide variety of bottoms. So their complaint of my test (only one unrealistic bottom) is false. I should specifically note that I did this testing to pick my own next anchor (as my bruce had been broken) so I had ever personal incentive to make it as realistic and useful as possible.

Evans

With regret CF has had to delete the original e mail from Tania at Rocna to Peter and Craig Smith and Steve at Rocna which was published without the confirmed authority of the author. A second e mail which was the reply from Craig Smith also had to go for the same reason.

However, the above synopsis by Estarzinger highlights some of the major points from the e mails.

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Old 21-10-2011, 18:41   #105
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Re: A Second Wind for Rocna

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It implies that the Smith's knew absolutely that the Chinese ROCNAs were not to spec at that time.

I am flabbergasted that they provide 'tuned' anchors for testing and more that anchor testers would let them do so.
I can confirm that the email is genuine.

I have dozens more along the same lines.

Dont be flabbergasted, its the nature of the beast.

They also knew of the 420 use in May this year when I confirmed it to them and gave specific detail to them by email so that they could take back the manufacturing license from HF.

How CMP play it now is still to be seen but the same performers are still in the back office circus.

With the 2nd huge thread now being pulled early this morning on YBW after specific revelations were posted it will be interesting to see what comes next and on what forum.
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