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Ubergeekian
Well-Known Member
Hear hear! I wonder if Pa Smith knows what impression of the company his lad is giving?
Brian@Fortress
Well-Known Member
Well stated Twister Ken. Once again, after talking with hundreds, if not thousands of Bruce, CQR, Danforth, and Delta owners over the years, I have nothing but great respect for those anchors.
And another point: Either you are humble, or you will be humbled. No matter what the generation of anchor, it will fail in one circumstance or another. Every anchor has some flaw in its design that will insure this.
This young man from Rocna is not humble, as apparently he thinks that the Rocna is the perfect anchor and all others are rubbish.
That's a shame, because the Rocna does have obvious flaws, which I am reluctant to discuss, and that's not my opinion, it's the opinion of an expert who designed anchors to hold boats and platforms in a wide variety of sea bottoms, water depths, and wind conditions for over 40 years.
So Craig, I advised you on this once before: Focus on your product's worthwhile features & benefits, and be respectful of your competitor's reputations. They earned them. At this time, your product has not, but maybe it will one day in the future.
All the best,
Brian
Fortress Marine Anchors
30boat
N/A
I for one would like to know what those flaws are.I'm not interested in belitlling the Rocna,which is a proven product,but it's useful to know what those weaknesses are.
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noelex
Well-Known Member
Expressing the view that the anchor that is holding my boat at the moment is "doomed" isn’t very helpful you don’t explain the conditions where this applies or the reasons behind these conclusions
These forums are all about information. You obviously have views about the performance of Rocna anchors on various sea beds. Share them, instead of threatening to share them with the forum. Then we will learn something.
Views from knowledgeable people are always welcome. As a manufacturer you naturally have some vested interest, but also a lot of detailed and inside knowledge. After some debate I am sure we will get to the truth, or at least have the various options vigorously argued and we can make up our mind.
When the storm force winds are howling I really don’t care if the manufacturers representative is nice guy, politically correct and polite, or otherwise. I want the best anchor I can get. I want to know its strengths and limitations.
30boat
N/A
One of the problems could be the tendency to scoop up mud that if hard and sticky will clog the fluke preventing the anchor from resetting.
noelex
Well-Known Member
My experience with the Rocna shows that it certainly does bring up a lot of the bottom. After strong wind some other boats have commented something like “the anchorage will be twice as deep now” referring to how much sand and mud has been lifted up by the anchor. I am always happy to see this as it shows how deeply set the anchor was set.
Part of the reason is the anchor sets and buries deeply, which is good, but the concave blade does not shed the bottom sand/mud when retrieved as well as a convex blade. 30 seconds with the boat hook is necessary to push off the bottom sample you have dredged up.
I have watched the Rocna respond to large changes in the wind direction. It has always remained completely buried and seems to rotate without apparently moving. It does develop a list of 15 degrees or so during the rotation. This behaviour is much better than most anchors. This list disappears once the pull from the new direction is established.
My oversized Rocna will not rotate unless the wind speed gets to 30K.
The fluke clogging up does not have any potential to cause problems during a change in wind direction because the anchor stays buried, but when deploying the anchor a large amount of old mud, dried on the tip, could conceivably effect the anchor and I always clean the anchor by pushing off most of the mud and sand ,usually on retrieval.
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DogWatch
Guest
And yet again he has turned an interesting conversation away from the subject and onto his dad's anchor.
[sigh]What's the point?[/sigh]
[sigh]What's the point?[/sigh]
Kilter
Well-Known Member
Brian@Fortress
Well-Known Member
Nolex & 30boat,
You guys are right. Safety first, and above all. Political correctness be damned.
But if you don't mind, please let me first put the question to Craig, with all due respect:
"As a responsible manufacturer of anchors, which are obviously an important piece of safety equipment aboard a boat, you have certainly conducted extensive holding power tests in many common sea bottoms.
With this in mind, you must know which type of bottom conditions the holding power of the Rocna anchor will be dramatically reduced.
Considering the importance of this information, please share it with your current or potential customers."
Safe boating,
Brian
Fortress Marine Anchors
P.S. DogWatch - Sorry, I tried to exit stage door left several posts ago, and I apologize if I also helped to stray the post away from the original topic.
You guys are right. Safety first, and above all. Political correctness be damned.
But if you don't mind, please let me first put the question to Craig, with all due respect:
"As a responsible manufacturer of anchors, which are obviously an important piece of safety equipment aboard a boat, you have certainly conducted extensive holding power tests in many common sea bottoms.
With this in mind, you must know which type of bottom conditions the holding power of the Rocna anchor will be dramatically reduced.
Considering the importance of this information, please share it with your current or potential customers."
Safe boating,
Brian
Fortress Marine Anchors
P.S. DogWatch - Sorry, I tried to exit stage door left several posts ago, and I apologize if I also helped to stray the post away from the original topic.
PeterR
Well-Known Member
I used to have a Danforth and it always seemed to work well in east coast mud until one morning I woke to find myself half a mile further up Pyfleet Creek than when I anchored the previous evening. I can only assume it broke out on the turn of the tide and took half a mile to reset.
I have not used one since until we chartered from Palermo last year. I did not notice at takeover but one of the flukes was slightly bent and it proved to be almost impossible to get it to set. When we got back I checked around the marina and nearly all the boats were equipped with Danforths and about 50% had bent flukes. I would not dream of using one any more except perhaps as a lunch time kedge.
I have not used one since until we chartered from Palermo last year. I did not notice at takeover but one of the flukes was slightly bent and it proved to be almost impossible to get it to set. When we got back I checked around the marina and nearly all the boats were equipped with Danforths and about 50% had bent flukes. I would not dream of using one any more except perhaps as a lunch time kedge.
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DogWatch
Guest
So is the problem not the anchor itself but the fact it is out of copyright and now copied by anyone with a spare bench in the corner of a Midlands workshop?
My current danforth is made from girders, it would take some going to bend it I imagine.
Boo2
Well-Known Member
Please understand that I don't want to start a flame war here, but I would appreciate short factual information about conditions where Rocna and other modern anchors do not do well.
Boo2
Woodlouse
Well-Known Member
Personally speaking, I've never dragged my anchor. And it's a CQR copy of all things!
When was it, (in the last 10 years or so) that it was decided suddenly that the CQR type was a disaster for anchoring, despite 50 years of satisfactory use?
I wonder how many peoples experiences of anchor dragging's have resulted from being in an unsuitable anchorage, in inappropriate weather. I know sometimes there is no alternative, but I know there can be situations where I could hardly blame an anchor for not staying set through the night.
When was it, (in the last 10 years or so) that it was decided suddenly that the CQR type was a disaster for anchoring, despite 50 years of satisfactory use?
I wonder how many peoples experiences of anchor dragging's have resulted from being in an unsuitable anchorage, in inappropriate weather. I know sometimes there is no alternative, but I know there can be situations where I could hardly blame an anchor for not staying set through the night.
Maine Sail
Well-Known Member
To answer the original question, yes, I have had both my Danforth's and Fortress anchors break out and not re-set. We get a 9-12 foot tidal range here and 360 degree swings on the hook are not uncommon. I now use the Fortress as my dedicated stern anchor where the direction of pull is a known commodity.
Brian@Fortress
Well-Known Member
Soft mud bottoms
I don't want to start a flame war either. After all, its almost Christmas. However, safety is at risk here, and that's more important.
The bottom conditions are soft mud, where all anchors (including Fortress) will suffer a significant loss of holding power capability.
Many years ago we conducted extensive tests in these bottoms, which led us to design and later patent the adjustable fluke angle.
We found that by opening up the shank / fluke angle from 32° to 45°, we could dramatically increase the fluke resistance and holding power in these problem soft mud bottoms.
The Rocna anchor has a non-adjustable, fixed shank / fluke angle, which is configured for hard soil penetration. This absolutely guarantees that performance will suffer in softer soils. To what percent, Rocna must know if they have done their homework. It could be 40% or much greater.
Saying that the Rocna is doomed in a particular bottom might have been overly dramatic, but a 40% loss of holding power in soft mud could be the difference between safety during a storm or your boat ending up in splinters along the shoreline.
If you are anchoring in soft mud, and you are spending any amount of time on the hook, then I have two simple words of advice for your anchor: Size up.
I hope this information has been helpful.
Brian
Fortress Marine Anchors
I don't want to start a flame war either. After all, its almost Christmas. However, safety is at risk here, and that's more important.
The bottom conditions are soft mud, where all anchors (including Fortress) will suffer a significant loss of holding power capability.
Many years ago we conducted extensive tests in these bottoms, which led us to design and later patent the adjustable fluke angle.
We found that by opening up the shank / fluke angle from 32° to 45°, we could dramatically increase the fluke resistance and holding power in these problem soft mud bottoms.
The Rocna anchor has a non-adjustable, fixed shank / fluke angle, which is configured for hard soil penetration. This absolutely guarantees that performance will suffer in softer soils. To what percent, Rocna must know if they have done their homework. It could be 40% or much greater.
Saying that the Rocna is doomed in a particular bottom might have been overly dramatic, but a 40% loss of holding power in soft mud could be the difference between safety during a storm or your boat ending up in splinters along the shoreline.
If you are anchoring in soft mud, and you are spending any amount of time on the hook, then I have two simple words of advice for your anchor: Size up.
I hope this information has been helpful.
Brian
Fortress Marine Anchors
Brian@Fortress
Well-Known Member
Rocna anchor - Clay bottom anchor test results
Gents,
The 40,000 member Swedish Cruising Association has been conducting anchor holding power tests off of their coast for over 20 years. They take boating very seriously over there, as 1 in 7 Swedes owns a boat.
Below is a link to a page with the results of a test they conducted this past summer in a clay bottom near the shoreline:
http://www.watski.se/mail/anp/ankartest.pdf
As you will note, the Rocna and Bugel "roll bar" anchors did not perform very well, as they achieved only two stars out of a possible five.
I am working on an English translation and I hope to provide one shortly.
Recently I discussed Rocna with Robert Taylor, a former long-time US Navy soil mechanics and anchor design expert. He pointed out that "the big roll bar is their means of orienting the anchor to engage the fluke, and it has a similar influence to that of the wings on the Bruce anchor for causing the anchor to roll towards the flukes, but the big roll bar might inhibit penetration in mud."
Maybe the roll bar was a factor in the Rocna's and Bugel's poor performance in penetrating and holding in these clay bottom tests.
Safe boating,
Brian
Fortress Marine Anchors
Gents,
The 40,000 member Swedish Cruising Association has been conducting anchor holding power tests off of their coast for over 20 years. They take boating very seriously over there, as 1 in 7 Swedes owns a boat.
Below is a link to a page with the results of a test they conducted this past summer in a clay bottom near the shoreline:
http://www.watski.se/mail/anp/ankartest.pdf
As you will note, the Rocna and Bugel "roll bar" anchors did not perform very well, as they achieved only two stars out of a possible five.
I am working on an English translation and I hope to provide one shortly.
Recently I discussed Rocna with Robert Taylor, a former long-time US Navy soil mechanics and anchor design expert. He pointed out that "the big roll bar is their means of orienting the anchor to engage the fluke, and it has a similar influence to that of the wings on the Bruce anchor for causing the anchor to roll towards the flukes, but the big roll bar might inhibit penetration in mud."
Maybe the roll bar was a factor in the Rocna's and Bugel's poor performance in penetrating and holding in these clay bottom tests.
Safe boating,
Brian
Fortress Marine Anchors
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Salty John
Well-Known Member
Tha anchor wars:
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Twister_Ken
Well-Known Member
What a shame they didn't test a CQR!
Brian@Fortress
Well-Known Member
and if they had tested the CQR, and it out-performed the Rocna as the Bruce copy did, ol' Craig's head would have been spinning around like that girl in the Exorcist.