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Old 03-07-2011, 11:39   #556
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Re: Rocna Size

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Originally Posted by conachair View Post
in years of anchoring in various continents both sides of the equator I've never met anyone with a bent anchor and never heard of an anchor failing, other elements of the system yes, but an anchor never.

Again, this isn't to condone rocna management behaviour in any way but a rant against the "your kids will die" sensationalist rubbish.
Well, mate, let me add another to the list of folks who have personally bent anchors. This includes a couple of steel Danforths (years ago), both shanks and flukes, and more recently, a genuine Bruce, 20 KG. The latter was caught under an abandoned mooring and to my surprise, one of the palms bent, but not the shank. Still worked ok as far as I could tell, but I took it to a machine shop in Hobart which had a huge hydraulic press... and they couldn't get it to bend back all the way!.

To my personal experience we might add the bent or otherwise buggered anchors on display on the bows of many a boat viewed in marinas around the world.

These observations don't lead me to worry that "the kids gonna die", but simply to recognize that anchors do bend in use at times, and that great strength is not a bad thing to strive for in their design and manufacture.

And on the issue of Manson "copying" the Rocna design, it is equally valid to say that Rocna stole their design basics from Buegel (sp?).

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Old 03-07-2011, 12:03   #557
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Re: Rocna Size

Why is "copying" good design features a bad thing, as long as no patents are violated? Copying what works, then adding your own new twist (no pun intended) is what got us the great anchors we have today. For example, the Fortress is a "copy" of the Danforth, with its own special materials and tweaks. It could be easily argued that the Rocna "copied" various clever features from the Spade, Delta and Buegel anchors. I think even Peter Smith would freely admit that he looked at what worked and what didn't work in various existing anchors, then combined what he liked with some of his own good ideas.

As to bent anchors--much more common than I would like to see. Check out any boatyard, large marina, or harbor where commercial fishermen dock and you will see at least several bent anchors. Many of these are knock-offs of famous makes, but some of the originals too. I was anchored right next to a boat that bent its Chinese-made Bruce knock-off in a very mild cold front wind shift. It was nothing that should have taxed any anchor, yet the anchor came up with a serious bend in the shank. The bottom was pure muddy sand in Boot Key Harbor.

It seems logical to me that if you produce a SHHP anchor it will require super-high strength in order to match.
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Old 03-07-2011, 12:13   #558
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Re: Rocna Size

""nit picking" the Manson Supreme for over four years claiming their product was inferior and used inferior steel compared to the Rocna's 800Mpa shank steel."

Didn't CS post about how the 'abysmal' steel in the Manson was a safety hazard and that purchasing one put your family at risk?

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Old 03-07-2011, 12:43   #559
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Re: Rocna Size

Is there agreement that even a slightly bent shank may keep an anchor from setting right (or resetting after a wind change that bent the shaft)?

If true, then a design that minimizes the chance of a bent shank seems really important. I can't remember any anchor test that tried to put a high side loading on a dug in anchor.

Obviously stronger steel is harder to bend but a shorter shank that's also taller could be even more important -- like the Supreme's shank.

So even if the Rocna wasn't fibbing about the steel strength, the Supreme may be a better anchor.

I guess no one ever told those guys over at Manson that they can only build poor knock-offs.

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Old 03-07-2011, 13:02   #560
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Re: Rocna Size

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If true, then a design that minimizes the chance of a bent shank seems really important. I can't remember any anchor test that tried to put a high side loading on a dug in anchor.
Quite a few anchor tests have done just that. In the Sailing Foundation tests back in the '90s they tested both straight line pull, and then they pulled the anchors at 90 degrees to the original pull, damaging several anchors in the process. Usually the anchors that were damaged were also the ones producing very high holding power--like the Fortress or the Danforth types. Practical Sailor also did some tests on veering, and more recently John Knox did some tests that were published.

These tests indicate that some anchors are subject to bending, even if not fouled, due to their very high holding power. This is one good argument for using a two-anchor set if you anticipate a wind or current shift and high loads.
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Old 03-07-2011, 13:10   #561
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Re: Rocna Size

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This is one good argument for using a two-anchor set if you anticipate a wind or current shift and high loads.
I have never anchored anywhere that did not have wind/current shift or both.

What am I missing?
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Old 03-07-2011, 13:17   #562
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Re: Rocna Size

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What am I missing?
You haven't been to the Caribbean. I was in St. Thomas one time when it took the local radio station a few days to realize they were broadcasting the same old weather report from days earlier--the wind can be from the same direction for weeks or even months at a time. Down in the San Blas you really didn't need to get any weather reports until it was time to leave to go someplace--pretty much what you saw is what you got. On the other hand, in New England we often have winds that go around the clock several times each day, even if you don't have current to contend with.
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Old 03-07-2011, 22:23   #563
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Re: Rocna Size

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Again, this isn't to condone rocna management behaviour in any way but a rant against the "your kids will die" sensationalist rubbish.
If that is in relation to my post. My post which said something along those lines was in response to the 'Oh it's only a anchor not brain surgery' comment from Chris.

And as we all know anchors do keep you alive while your asleep we'll also know that ALL anchors do that. The comment wasn't specific to Rocna only and applies equally to every anchor.

As a FYI I've seen and bent many a anchor. Mind you most were bent during testing programs, commonly during veer testing. But we see many bent ones including a Supreme (a slight shank twist) and sitting next to that is an equivalent sized (35lb/15kg) Rocna with a bent shank. We can't work out how he's done them though, both are off the same boat, one of them stinky no sails sort. To think all shanks won't bend if pushed hard enough is just deluding yourself. How hard you have to push is the difference. We will be doing a bit of a play looking at that tomorrow, just built a jig so we can lock then 90 degrees to the pull. We'll also be doing Delta, a Delta knock-off and a Bruce knock-off.

I'd say the most commonly seen anchor over the years with a bent shank is actually genuine CQR's. Mind you there are around a gazillion in use so that's probably understandable.

Quote:
And on the issue of Manson "copying" the Rocna design, it is equally valid to say that Rocna stole their design basics from Buegel (sp?).
Spade theory and Delta shank. The reason there is a rollbar is due to Alain Mr Spade being very clever in writing his patents regarding the whole tip arrangement on the Spade. Manson has publicly said they liked the Spade so much they use the same design theory, as did Rocna, Ultra and a couple of others.

Personally I don't have major issues with that. The Spade is the bees knees as Rocnas web video and testing shows, not that I think they have published that for some reason. To get Spade benefits without the Spade price can only be good for the average boater in our books, which was Petes target, one I think he hit right on the head, as did Manson. I would include Ultra but being all SS there is a large price difference.

And as a FYI both the Supreme and Rocna were being developed at the same time 10kms apart unbeknown to both outfits. A pure coincidence. Holdfats will say no but how would they explain the Supreme hitting the market at the same time already Lloyds Approved when it's taken Holdfast 2-3 years to get a Design Approval.

Lets play Rocna Marketing Dept using only the info in the para above

As the Supreme arrived on the market at the same time as the Rocna, +/- bugger all, all fully Lloyds Approved and Holdfast took 2-3 years to get their Approval that means it must be a fact the Supreme was designed 3 years prior to the Rocna, in which case the Rocna must be nothing more than a not cheap copy of the Supreme.

It's easy to screw with things if you want to isn't it? And No No No, the Rocna is not a copy of the Supreme. I was there at the time.
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Old 03-07-2011, 23:21   #564
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Re: Rocna Size

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If that is in relation to my post. My post which said something along those lines was in response to the 'Oh it's only a anchor not brain surgery' comment from Chris.

And as we all know anchors do keep you alive while your asleep we'll also know that ALL anchors do that. The comment wasn't specific to Rocna only and applies equally to every anchor.

As a FYI I've seen and bent many a anchor. Mind you most were bent during testing programs, commonly during veer testing. But we see many bent ones including a Supreme (a slight shank twist) and sitting next to that is an equivalent sized (35lb/15kg) Rocna with a bent shank. We can't work out how he's done them though, both are off the same boat, one of them stinky no sails sort. To think all shanks won't bend if pushed hard enough is just deluding yourself. How hard you have to push is the difference. We will be doing a bit of a play looking at that tomorrow, just built a jig so we can lock then 90 degrees to the pull. We'll also be doing Delta, a Delta knock-off and a Bruce knock-off.

I'd say the most commonly seen anchor over the years with a bent shank is actually genuine CQR's. Mind you there are around a gazillion in use so that's probably understandable.

Spade theory and Delta shank. The reason there is a rollbar is due to Alain Mr Spade being very clever in writing his patents regarding the whole tip arrangement on the Spade. Manson has publicly said they liked the Spade so much they use the same design theory, as did Rocna, Ultra and a couple of others.

Personally I don't have major issues with that. The Spade is the bees knees as Rocnas web video and testing shows, not that I think they have published that for some reason. To get Spade benefits without the Spade price can only be good for the average boater in our books, which was Petes target, one I think he hit right on the head, as did Manson. I would include Ultra but being all SS there is a large price difference.

And as a FYI both the Supreme and Rocna were being developed at the same time 10kms apart unbeknown to both outfits. A pure coincidence. Holdfats will say no but how would they explain the Supreme hitting the market at the same time already Lloyds Approved when it's taken Holdfast 2-3 years to get a Design Approval.

Lets play Rocna Marketing Dept using only the info in the para above

As the Supreme arrived on the market at the same time as the Rocna, +/- bugger all, all fully Lloyds Approved and Holdfast took 2-3 years to get their Approval that means it must be a fact the Supreme was designed 3 years prior to the Rocna, in which case the Rocna must be nothing more than a not cheap copy of the Supreme.

It's easy to screw with things if you want to isn't it? And No No No, the Rocna is not a copy of the Supreme. I was there at the time.

It is time the debate around who was first with their design was put to bed once and for all.

One of the tasks given to me during my time working for them was to undertake a detailed and comprehensive study of the development timeline and details surrounding this very topic.

Legal experts were consulted, patent lawyers were consulted, hundreds of pages and files were compiled and studied and 501 billing hours were put in to reach a conclusion. The file is 4 inches thick.

The conclusion was that there was no breach of the Rocna IP by Mansons and that the Supreme was developed at the same time and independant of any knowledge of the Rocna.

This was accepted, reluctantly, by Holdfast and because I was not able to take the alledged breach to a satisfactory conclusion for Bambury he refuded to pay for the work (501 hours) done. It still remains unpaid to this day.

So forget any claims made that the Supreme is a copy of the Rocna or vice versa, they both hatched at the same time.
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Old 04-07-2011, 00:29   #565
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Re: Rocna Size

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But more than this, the Rocna has always been significantly over-engineered to ensure it can withstand the most challenging conditions that might be faced on the sea.

This was confirmed recently with exceptional results in destruction testing independently conducted by D.M. Standen Limited. A galvanised 55kg model held up to a massive 28.7 tonnes of load – this equates to 670% of RINA’s SHHP proof load, and well beyond the point at which the connected chain would fail in real life use

Whether or not the anchor would hold up to a straight pull was never the question. I have never heard of ANY anchor which failed in this mode. You could probably make an anchor out of pot metal and it would hold up to a straight pull. This is simply not the problem. Rocna is answering a question no one asked.

The Rocna website used to say that high strength steel is absolutely essential for the shaft of the anchor, because it has to be made relatively thin for proper weight distribution. It used to say that a shank bending under a side load is a common failure mode for anchors.

Now if Rocna would test their anchor with the downgraded steel in a side load and show that the chain will break before the shank bends -- THEN I would be perfectly satisfied. Somehow I don't think so.

That would be a good test -- take a few modern anchors, including a New Zealand made Rocna and a Chinese made Rocna, and put the shanks under side loads -- a "common failure mode" as Rocna used to say -- and I believe they said so correctly. Compare the results. Then people can make up their own minds whether the Chinese Rocnas with the downgraded steel are worth the price or not.
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Old 04-07-2011, 02:03   #566
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Re: Rocna Size

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They admitted the mistake, refunded anyone that wanted it and continue to build and sell fantastic anchors. The test results were not negative for Rocna. The bad metal anchors were still 471 % stronger than they needed to be. The fact is that I have beaten on my anchor repeatedly... loaned it to guys to hang heavier boats than mine off during hurricanes and the thing has been 100% bulletproof. I believe very strongly in proven facts and my anchor has beyond any shadow of a doubt proven to be the most reliable thing on my boat. As long as their anchors get positive reviews form the people that use them they will continue to outsell all the others.

I have never loaned my anchor out to anybody, how do you do that? Just unhook it and give it to your Buddy? How many of you Guys just loan your anchor out........
I have never heard of such a thing
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Old 04-07-2011, 03:34   #567
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Re: Rocna Size

It appears that NZ made Rocna's are now all gone. Was in a Chandlery here in NZ which had Rocna's on special, they all had the Rocna name cast into the bottom, so they must be Chinese made ones. When asked if they were concerned re the bending shanks and the alledged use of lesser quality steel they said "no not at all".
coals to newcastle I guess!
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Old 04-07-2011, 06:15   #568
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Re: Rocna Size

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We will be doing a bit of a play looking at that tomorrow, just built a jig so we can lock then 90 degrees to the pull. We'll also be doing Delta, a Delta knock-off and a Bruce knock-off.
Now that will be very interesting. Take some pics

I genuinely never even heard of a bent anchor cruising round the atlantic, from the exeprience of yourself an others that seems to be not very typical, I stand corrected.
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Old 04-07-2011, 08:05   #569
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Re: Rocna Size

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I have never loaned my anchor out to anybody, how do you do that? Just unhook it and give it to your Buddy? How many of you Guys just loan your anchor out........
I have never heard of such a thing
I've loaned my Rocna 25 kg anchor a few times, mostly to people who wanted to see for sure how it would fit in their bow roller. Lower it into a dink, unhook it, dinghy over, hook it up, hoist away. Easy karma. *grin*
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Old 04-07-2011, 09:24   #570
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Re: Rocna Size

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You haven't been to the Caribbean. I was in St. Thomas one time when it took the local radio station a few days to realize they were broadcasting the same old weather report from days earlier--the wind can be from the same direction for weeks or even months at a time. Down in the San Blas you really didn't need to get any weather reports until it was time to leave to go someplace--pretty much what you saw is what you got. On the other hand, in New England we often have winds that go around the clock several times each day, even if you don't have current to contend with.
I understand that and also understand that they can have some strong currents too. Seems moving about would be common there too.
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