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Old 16-04-2011, 11:49   #91
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Re: How to Test Anchors?

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Originally Posted by Nicholson58 View Post
As long as the testing techniques are identical, such as on the wet beach against a load cell, the data will reasonably rank the anchors relative to one another. This is at least a less subjective method. It would be nice to see the tests repeated on a gravel or rocky or grassy bottom - etc.

We carry a CQR 75 # primary that was on the boat when we bought it. (3 other anchors also on board). Rocna looks far superior (relatively) according to level tests against equally sized anchors. Here is the interesting data for us. For our boat Rocna recommends a 55 Kg anchor - abut 80 % heavier than the CQR. It has about the same girth and length as the CQR but is massive. I suspect that part of its improved capability is based on the ability to force its way into the bottom. Pulling tests show it has an uncanny way of righting itself and digging in in about its own length. I will keep my CQR but will probably make the Rocna my new primary.
Chances are that once you've gotten comfortable with the Rocna, you'll leave your CQR on shore.
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Old 16-04-2011, 13:43   #92
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Re: How to Test Anchors?

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Originally Posted by GMac View Post

There seems to be a search for the 'best' anchor when there just isn't one that can hold that title and there is unlikely to be one in the foreseeable future.
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I disagree, I think that with a good testing program you could determine which anchors are 'best' under specific conditions of seabed & loading. And, while it would be somewhat subjective, you could determine which anchor or which several anchors are best in most conditions and highlight the conditions where an alternative would be better. Also I think that close observation of the physics of anchors could lead to tweaks that would somewhat improve the designs that already exist.
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So by disagreeing you are actually agreeing there is 'a best for a given set of circumstances' but there is 'no one best all over' anchor. That's what I've been saying for years.
No, I am not agreeing by disagreeing. I just disagreed. I said one could determine the best anchor for each circumstance, and that there would be an anchor that is best or almost best in most situations implying 'best all around'. Your original statement said there wasn't and wouldn't be a best anchor which I inferred to mean 'best all around'.



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So to get any real true holding numbers you do have to do a lot of pulls on a lot of varying seabeds, which does doesn't happen in 99% of tests.
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Exactly, to get any kind of valid results for statistical comparison you need to have 30-50 tests of each anchor in each kind of seabed under each loading scenario.
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Never going to happen and even if someone did that it the results would still be only average. To get a true result you'd need to do the 30-50 pulls with a large range of boats using a large range of rodes all operated by a large range of different people......... just like it does in real life. So as I said, it's never going to happen.
With money it could happen, though not with a lot of boats. That's why I proposed a testing scheme that cut out all the extraneous elements of the test leaving the anchor, the rode, soil underwater and a load that can be varied in magnitude and direction. And I proposed secondary testing on actual boats in the real world to check actual loads and direction of loading. I should have included monitoring how a large number of people set their anchors.


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We test anchors a lot but have found the best information as to what works and what doesn't is asking the punters who use them. .
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Best info doesn't mean it's particularly good info, only that it is better than the very limited physical testing that has been done or no info at all.

I'm not trying to knock people's opinions but anecdotal evidence is pretty subject to a number of errors. Key among them being people's tendancy to feel more positively about whatever item among several considered once they've made a choice they've bought it (general observation) and the limited number of anchors most boaters have experience with, thus limiting their ability to make comparisons.

Anecdotal evidence can be wrong even among very savvy observers. In the late 80's 'observational' studies tauted high dose chemotherapy with bone marrow transplants as an effective way to 'dramatically' shrink tumor size in women with breast cancer. Several 10's of thousands of women underwent the procedure before well designed studies showed the procedure increase mortality over conventional treatments.

I'm not saying we should ignore people's observations since at this point all we have is anecdotal reports and poorly designed tests, I'm lamenting the fact that we are unlikely to get much better until somebody ponies up a bunch of dough for better.
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Sort of agree but if we agree most testing is flawed, and most deep in the anchor game know they are to varying degrees, what's left? The end users. Ask enough and you soon get very clear patterns as to which anchors people have which issues with. The observations we garner from the end users do tend to parallel what we see in our testing. Combine the lot and there is a reasonably clear picture as to what anchor/s are best in what conditions.
Once again flawed testing backed up by anecdotal evidence or visa versa. Better than nothing, but really only good for determining which anchor(s) is/are vastly better in comparison to others. It is not good for determining which anchors are marginally better which is the point we are at now. Vendor hype aside, I am unwilling to believe that the new crop of anchors(rocna, Manson, etc) are more than marginally better than the last crop (CQR & Bruce). Barring some really well done testing by independant parties, in 10yr or so I will reassess that belief.
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Old 18-04-2011, 09:36   #93
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Re: How to Test Anchors?

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Rock Solid Test Results » Rocna Anchors

Here is a straight up test of several anchors. The set up is that all anchors were tested in the same conditions. They were pulled in line with a measuring instrument under the same loading conditons.
Unfortunately, the chart from that web site is not accurate. Attached is the actual Excel spreadsheet that was sent to me by Chuck Hawley of West Marine, who conducted this test which was later published in Sail, Power & MotorYacht, and Yachting Monthly magazines.

This attached spreadsheet contains the DATA TABLE which gives a pull by pull analysis of how each anchor performed in this test, and at each location. If you are handy with Excel, then you can sort columns to get different analysis information.

I have also attached two jpg images, one which shows the totals of the Rocna and the Fortress, and the other which shows the test notes with details of a false pull reading that Rocna benefitted from at the New Brighton location, which is one of three locations where they tested the anchors.

This illustrates how the published results of an anchor test might not be an accurate representation of what actually occurred.

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Fortress Marine Anchors
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Old 18-04-2011, 10:10   #94
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Re: How to Test Anchors?

Maybe I'm looking in the wrong place, but West Marine seems to have exorcised the full write up of that anchor test from its Web site, replacing it with a very short version that basically only talks about how well the Rocna and Manson did. I suppose the failure of the West Performance 2 isn't something they wish to publish anymore. I still think the basic takeaway from that attempt at a test is that if you have very unusual and uneven holding ground you will get unusual and uneven test results.
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Old 18-04-2011, 10:22   #95
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Re: How to Test Anchors?

I give up! For the "good" anchors you can play with these numbers as you wish to get positive results.

I don't really feel that for the most part these tests can be compared for the most part. To be comparable would need to be done in a lab with conditions that could be controlled to be the same for all tests. And even then all you could say at the end is anchor X did Y in Z conditions.

PS - I want to be able to see the video of the anchor setting and releasing, no number games with that!
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Old 18-04-2011, 15:39   #96
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Re: How to Test Anchors?

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PS - I want to be able to see the video of the anchor setting and releasing, no number games with that!
Easy to fudge video too. Just for example, how do you know the video is taken in the same spot with the same bottom conditions? Besides, I'm not sure what the video tells you other than the anchor digs into the bottom like you would like it too. I have dived on many, many anchors and you can't always tell what the holding ability is by how they look on the bottom. In ooze the anchor will disappear but the bottom can still offer very little resistance to dragging. In very hard sand sometimes only the point of a plow or the tips of a Danforth get dug in, yet that may be plenty for many knots of wind. I've seen a CQR apparently just lying there on the bottom on its side yet we were unable to drag it with the engine, and I've seen an anchor totally cockeyed, twisted around with the chain apparently fouling the thing, and it still held. Looks can be deceiving, but diving on anchors has given me further evidence that the loads may not be as great as many seem to believe.
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Old 18-04-2011, 16:05   #97
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Re: How to Test Anchors?

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By the way, I do have a manual windlass but I try to haul the anchor in hand over hand as much as possible as part of my exercise routine and I have only very rarely anchored in 50 feet--more often it is 10 feet or less.

Arr. I understand your reluctance to support the heavier anchors precribed by many pacific cruisers such as J Cate and Evans.
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Old 19-04-2011, 17:17   #98
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Re: How to Test Anchors?

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Once again flawed testing backed up by anecdotal evidence or visa versa. Better than nothing, but really only good for determining which anchor(s) is/are vastly better in comparison to others. It is not good for determining which anchors are marginally better which is the point we are at now. Vendor hype aside, I am unwilling to believe that the new crop of anchors(rocna, Manson, etc) are more than marginally better than the last crop (CQR & Bruce). Barring some really well done testing by independant parties, in 10yr or so I will reassess that belief.
Sorry but 'marginally better' is well inside the variables that come with anchoring.

No the new crop are not marginally better than the CQR's, Delta's, Bruce's etc, they are significantly better. That's well proven already.

The big question is do they really need to be for most people? Nope.
If you are having no problems with your current set-up should you change? Nope
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Old 19-04-2011, 17:33   #99
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Re: How to Test Anchors?

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No the new crop are not marginally better than the CQR's, Delta's, Bruce's etc, they are significantly better. That's well proven already.
I haven't seen the "well proven" part in a reliable, published, third-party test, done in a scientific manner. Sure, there have been tests done, but they haven't proven anything that I can see other than the tests were not well designed. This is one reason I made my original post--we need better anchor testing. I understand you do your own testing and that has proven to you what you consider to be better, but I don't think anything has been proven with regard to these new anchors. Over at another forum you also post on we have just seen that the claimed material strength and certification of one of these new generation anchors is false. What other claims may be false?
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Old 19-04-2011, 18:15   #100
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Re: How to Test Anchors?

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No the new crop are not marginally better than the CQR's, Delta's, Bruce's etc, they are significantly better. That's well proven already.
Send me:
A) the test results (including preliminary raw data with reasons for not including any data point in final results),

B) testing protocol (including equipment used, conditions of test, method of characterizing the seabed, procedures for setting and loading the anchors),

C) person(s) or group(s) performing the testing and their affliations, (no don't actually send them, tell me who they are)

D) and conclusions drawn.
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Old 20-04-2011, 11:33   #101
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Re: How to Test Anchors?

Another aspect of anchor testing - simple strength of material, construction and design.

Manson Anchors: Supreme Anchor high standards
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Old 20-04-2011, 12:49   #102
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Re: How to Test Anchors?

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if they float, yer on acid.......
You obviously lived through the '60's!
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Old 20-04-2011, 18:15   #103
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Re: How to Test Anchors?

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Another aspect of anchor testing - simple strength of material, construction and design.
Yes, interesting, isn't it? Bruce was always touting the strength of its anchors, which I think encouraged CQR to go on an advertising binge emphasizing strength with a photo of an anchored boat in a big sea stretching its chain rode absolutely bar taught while the boat rears back on a wave. Remember that one? Then BoatUS and Cruising World did an anchor strength test back around 1989 that got a lot of attention. They pulled various anchors to destruction with a hydraulic test rig. All of that seemed to disappear after the early 90s when holding power became all the rage, with Fortress and Danforth pushing that theme in their advertising, and then Delta. Finally Spade, Bulwagga, Rocna, and Manson arrived on the scene all touting super fast and reliable setting, along with high holding power and resistance to roll out when veering. Yet by the this time just about everything was being manufactured in China, including many of the old standby anchor designs of the past, and none of the "new generation" kids on the block could gain much traction at their high price points relative to the Chinese made versions of the old guard.

Unfortunately, "made in China" still carries some stigma, not totally unfounded due to numerous reported problems with equipment that no longer lasted like the old stuff did. So manufacturers have a tricky problem. Not made in China and they can't compete on price. Made in China and they suffer from a perceived quality problem, rightly or wrongly. I suspect there is a tightrope to be walked between lowering the price by going to China while maintaining decent standards so you don't lose your customers due to quality issues. I imagine it is a difficult tightrope to walk. I used to work for a company that switched manufacturing to China. It took much effort to get the new manufacturer up to snuff quality-wise, but eventually they could produce a superior product. However, the minute you turned your back or stopped checking, some little aspect of the manufacturing process or material would be changed and you might end up with something that was unsellable. This meant that you had to test, test, test, much more so than if you were manufacturing in the West, which brought the cost back up, making that tightrope tighter.

In any case, I wonder if this incident will bring back the advertising about strength. How do you think the Manson Ray compares to your old Bruce?
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