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Old 30-10-2013, 07:40   #31
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Re: Mantus real world experience

Quote:
Originally Posted by noelex 77 View Post
I wish we could have a thread about anchors without 10 pages discussing shank strength. There are many other important attributes.

If you want to discuss shank strength, at least keep it balanced. Delfin, you seem strangly critical of a very open policy from Mantus with an offer to upgrade the shank, while at the same time ignoring the policy of Ultra, the anchor you own and use.

Ultra have done exactly the same thing that you seem so indignant about. They have strengthened their shank (incorporating some webbing into the design). They made no announcement of redesigning the shank, we don't even know when it occurred. Unlike Mantus, Ultra have offered no policy of replacing the older designs. There are no calculations from Ultra, or anyone else, about their shank strength before or after the change.

I am not knocking Ultra. They make a beautiful anchor and early indications are that it works very well. I don't think Ultra have in any way behaved badly (in fact the opposite). They saw a way to improve their product and incorporated this into the newer design. In the meantime, they offer a lifetime warranty that will replace a bent anchor (like Mantus). Seems very honourable conduct to me. I wish all anchor manufacturers would do the same.

However, I am puzzled why you are jumping up and down about Mantus here and on other sailing forums, when the very anchor on your bow, Ultra, have done the same thing in a less transparent way, with no offer to upgrade existing customers. You own an Ultra anchor costing over $6,000 ,but you are not making demands for them to calculate and compare shank strengths. Was your anchor before, or after the reinforcement? Do you know? Can anyone find out?

The above looks like I am singling out Ultra, which is not my intention. I mention them only because of the source of the criticism. There are other manufacturers that have announced they will upgrade the anchor shaft material in the future such as Anchor Right with their Sarca anchor. Many more won't tell us what their anchor shank material is eg Kobra, Delta etc so they can make changes without anyone knowing. If we do have discussion about shank strength, let's discuss all manufacturers in a balanced way.

Could I please make a plea that occasionally we are allowed to discuss issues such as setting and holding in different substrates, resetting ability etc, factors that are much more important to most users.
I believe the Ultra manufacturer indicated that after selling 10,000 anchors, 10 had bent. I asked the question whether the experienced failure rate was greater before the internal strengthening, but didn't get an answer, as you closed the thread first, so I have no idea whether it helped or didn't help. I would classify Ultra's change to be a marginal improvement to an anchor they want to be the best there is. I would classify Mantus' decision to upgrade the steel in their shank by nearly a factor of 3 to be a rather different level response that addresses an obvious weakness, and your equation of the two changes isn't terribly convincing. I think their policy of upgrading shanks great. I'm sure they've indicated a cost and a schedule, but I haven't seen that. Have you? If free, wonderful. If an upcharge to cover the additional cost, that also seems very fair.

The reasons the topic has remained of interest is because Mantus published spurious engineering data that someone decided to remove from the closed thread; that thread was closed for reasons unknown; there is still dancing around the question of whether the anchor can be used safely without the hoop; and the question of whether the change to a steel 3x stronger in the shank is an engineering tweak or an admission that what is out there isn't quite up to snuff has remained unanswered.
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Old 30-10-2013, 08:57   #32
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Originally Posted by colemj View Post
All of this was said when these guys were sussing out the Rocna fiasco. I am NOT suggesting that this is the case here, and don't believe it is. I'm just making the point that sometimes the bulldogs are doing good even if it seems petty or redundant to you at the time. I appreciate that, even when I have to skip past minutia that doesn't interest me. If it bothers you, ignore lists and scrolling are your friends here. Mark
Mark,

I guess there is the desire to participate in investigative journalism and the desire to participate in discussions about how different anchors work, anchor theory and best practices for us sailors that would like to know more about how to be safe on the hook.

I appreciate and respect the investigative journalism, but am more interested in what is going to keep me off the beach tomorrow.

With regards to the Rocna fiasco - I totally get the fury over the apparent deception, however I am curious about how many boats were actually affected by the material change. Did any shanks bend? Were any boats lost, directly attributable to the material change?

I am in no way endorsing or condemning Rocna, but really at the end of the day...

...How many boats are lost due to lack of understanding of correct anchoring techniques and lack of understanding of a given anchors qualities versus boats being lost due to material changes or shank weakness?

Just a random stab, I would guess it is a thousand to one - probably a lot higher.

If one was an economist one might talk about utility and value.

What is the utility of a thread that focuses on anchors specific abilities (minus shank issues) and anchor techniques versus an anchor thread that focuses on shank strength?

I would be fascinated if one would take a census of all boats grounded that were at anchor and look at the results.

Maybe I am just lousy and anchoring, or have a lousy anchor...

...yea I am running with a CQR and an Original Bruce.

You probably shouldn't listen to anything I say.
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Old 30-10-2013, 09:23   #33
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Re: Mantus real world experience

Delfin you are hurting the very cause you sought to promote. You have done this by breaking the first two rules of CF.
1. Be nice. Your posts are seen as attacking another CF member by many. This makes you seem biased whether you are or not.
2. Purposeful intended thread derailment. You accuse the moderators of some conspiracy yet it is apparent that you cannot simple rules. It is no surprise to me that you feel picked on, because you do not follow the rules of the culture that you choose to be part of. The original poster (op) has set the tone and purpose of this thread, and unless it goes against the values of CF, it should stay on the topic he chose.
Then when you break the rules it is some type of conspiracy? Do you see how silly that looks to people that have been here for many years?
If we could get to actual "interested emails" during your posts I bet there has been a surge in Mantus inquiry compared to your favored manufacturer. But your not doing much for your name or your anchor.
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Old 30-10-2013, 09:41   #34
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Re: Mantus real world experience

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Originally Posted by s/v Beth View Post
Delfin you are hurting the very cause you sought to promote. You have done this by breaking the first two rules of CF.
1. Be nice. Your posts are seen as attacking another CF member by many. This makes you seem biased whether you are or not.
2. Purposeful intended thread derailment. You accuse the moderators of some conspiracy yet it is apparent that you cannot simple rules. It is no surprise to me that you feel picked on, because you do not follow the rules of the culture that you choose to be part of. The original poster (op) has set the tone and purpose of this thread, and unless it goes against the values of CF, it should stay on the topic he chose.
Then when you break the rules it is some type of conspiracy? Do you see how silly that looks to people that have been here for many years?
If we could get to actual "interested emails" during your posts I bet there has been a surge in Mantus inquiry compared to your favored manufacturer. But your not doing much for your name or your anchor.
Sorry to disappoint you Newt, but I don't feel picked on. If the CF member you feel I am attacking is Mantus, well, I'm not sure what to say. A number of people have asked questions of someone who wants to sell a key piece of safety equipment to other boaters and uses the forum as a communication platform of an advertising message, in part which includes apparently bogus engineering information about their and competitor's products.

I take my hat off to them from a PR standpoint, because usually forums frown on such practices, so they are certainly very effective marketers. But because that commercial interest doesn't want to answer the questions posed doesn't mean they aren't valid or deserve to be left unanswered.

Not sure what culture you think you are a part of, but as far as I know, Internet forums are places where ideas are shared and questions answered in the public interest. If your sense of culture excludes the latter, then I will leave you to it.

And I have no favored manufacturer, just opinions. You have an opinion that Mantus in its current form is the best anchor for you. Wonderful. Seems a bit odd to me, given your commitment to your family's safety regarding interior wood on your boat, but who am I to judge?

I have opinions. All things considered, I think the Ultra is the best anchor available, which is why I bought one, but it is very expensive. On that basis, if someone asked my opinion on what is the best choice for a top performing anchor I'd have to say the Excel. My opinion on both is based on engineering specifications and objective test results. Your opinion on the Mantus seems to be based a sense of comradeship with the manufacturer. Just different approaches to the equipment selection process.
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Old 30-10-2013, 09:48   #35
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Re: Mantus real world experience

Quote:
Originally Posted by Delfin View Post
I believe the Ultra manufacturer indicated that after selling 10,000 anchors, 10 had bent. I asked the question whether the experienced failure rate was greater before the internal strengthening, but didn't get an answer, as you closed the thread first, so I have no idea whether it helped or didn't help. I would classify Ultra's change to be a marginal improvement to an anchor they want to be the best there is. I would classify Mantus' decision to upgrade the steel in their shank by nearly a factor of 3 to be a rather different level response that addresses an obvious weakness, and your equation of the two changes isn't terribly convincing. I think their policy of upgrading shanks great. I'm sure they've indicated a cost and a schedule, but I haven't seen that. Have you? If free, wonderful. If an upcharge to cover the additional cost, that also seems very fair.

The reasons the topic has remained of interest is because Mantus published spurious engineering data that someone decided to remove from the closed thread; that thread was closed for reasons unknown; there is still dancing around the question of whether the anchor can be used safely without the hoop; and the question of whether the change to a steel 3x stronger in the shank is an engineering tweak or an admission that what is out there isn't quite up to snuff has remained unanswered.
I have three things to say about this:

1. The fact that someone makes a change to something to improve its safety characteristic is not evidence that it was unsafe before. This is in fact a legal doctrine -- if you were suing Mantus for a bent anchor, the fact that they had substituted a stronger shank later would be absolutely and totally inadmissable in court. The reason for this legal doctrine is twofold: (a) don't want to discourage people from improving their products by increasing the risk that you will get sued; and (b) it in fact really doesn't mean anything -- maybe the thing improved was perfectly fine and the manufacturer is just making it even better. Or maybe he's just responding to some part of his customer base who are irrationally worried -- just to reassure them.

I am not with this saying that the Mantus shank is strong enough or it is not strong enough. What I am talking is this particular argument, which is carries no water.


2. Here is yet another reference to "spurious engineering data". I note that the tone of these postings has improved somewhat -- bravo. But "spurious engineering data"? What is that supposed to mean? "Spurious" means "fake", not just "wrong", and not a single calculation to show even wrongness has been offered here, just these inflammatory words. If you think the calculations are wrong -- then make your own calculations and show us. That's a perfectly reasonable discussion. But just throwing around words like this is not. And especially not just throwing them over and over again, without adding a shred of substance.


3. I don't believe anyone has done any "dancing" about the roll bar issue at all. Another false accusation in my opinion. The Mantus guys asserted that the anchor works without it, and showed a video. Someone else said it won't -- based, I presume, on speculation. I don't actually believe that anyone knows anything more than that, and so the only thing anyone can say is "it does too work!" "no it does not work" "does too!" "does not", which is obviously idiotic. I don't think anyone can be blamed for declining to participate in such a dialogue. Dignified silence in not "dancing". In fact it's something we could use more of around here.


That being said, and turning to the substance of the question, I spent a couple of years with a roll bar anchor and I don't personally like very much the whole idea of them. It seems to me a poor substitute for proper balance and ballast, and I wouldn't want one with or without the roll bar cut off. But don't ask me to prove that or argue with anyone, because I can't. I am not an engineer. It's just my uninformed opinion.
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Old 01-11-2013, 01:41   #36
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Re: Mantus real world experience

We apologize for the interruption of this thread, which is now open again.

We had to close it while we worked out internally the best way to keep the discussion on track. These anchor threads are unique and difficult cases -- they seem to uniquely inspire people to attacking and insulting each other -- which we absolutely do not allow on Cruisers Forum -- and at the same time, they are uniquely interesting and valuable for everyone since anchoring is such an important and difficult part of cruising.

In this thread we are discussing people's experience with Mantus anchors, positive and negative. Besides real life experience, discussion of the theory of how these anchors work is very valuable and very welcome. There has been some very interesting criticism of the strength of the Mantus shank, and of whether or not Mantus anchors will work or not with the roll bar removed. These discussions have gotten down to a level of detail which involves engineering calculations and how to measure beam strength and so far -- this is great stuff.

So please people -- discuss away. All points of view are welcome. What you MUST avoid, however, is provocation of conflict and personal attacks. You must keep you comments polite, respectful, factual. You are absolutely allowed to disagree with each other. You can say just about anything you want as long as you show proper respect for each other and behave like adults. This thread is on "hot topic" and will be strictly policed for rude or aggressive behavior.

I would also like to underline that there is a big difference between a naked assertion, and an argument supported by facts and logic. Everyone is entitled to an opinion, even an uninformed opinion, but don't confuse it with a worked-out argument. If you want to refute something someone has said, the structure of your post should not be "you're just wrong" (and all the more not "you're just wrong because you're an idiot" or "you're just wrong because you are a conspirator against Joe Blow" or "you're just wrong because you're trying to foist inferior goods on us"). It should be: "this particular thing you said is not correct, because x, y and z", based on facts and logic. If, for example, you want to say that the Mantus shank is too weak, it would be really good if you would show the objective basis upon which you came to that conclusion. Inevitably, we will have to do proper engineering calculations to say anything meaningful on that subject. I know we have a number of CF members who have the knowledge and skill to do them.

I am personally interested in the shank strength discussion -- I don't think we've even scratched the surface of how to calculate it. I am not an engineer, so I will sit back and watch those more knowledge than I figure it out. Engineering calculations are an objective thing -- someone will make them, and others will try to find flaws in them. Eventually the objective truth will be revealed. That's an absolutely normal and actually extremely useful discussion.

I think shank strength, as interesting as it is, needs to be kept in perspective of the comments of Noelex earlier in the thread -- nearly all shank-bending situations occur when anchors are raised, so this will not generally be an immediate safety issue. Nevertheless, of course, no one wants to have his main anchor out of commission in the middle of a cruise, because the shank couldn't stand up to some side loading when lifting the anchor out of a difficult bottom. By keeping in context I mean -- let's not get carried away, let's not get hysterical about it. It's probably not the direct safety issue that reliable holding, and reliable resetting are.

Cheers.
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Old 01-11-2013, 03:05   #37
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Re: Mantus real world experience

I remember greg from mantus saying you can use his anchor without the roll bar as a lunch hook or day time anchor. Seems simple enough to me
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Old 01-11-2013, 07:23   #38
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Re: Mantus real world experience

Quote:
Originally Posted by Dockhead View Post
We apologize for the interruption of this thread, which is now open again.

We had to close it while we worked out internally the best way to keep the discussion on track. These anchor threads are unique and difficult cases -- they seem to uniquely inspire people to attacking and insulting each other -- which we absolutely do not allow on Cruisers Forum -- and at the same time, they are uniquely interesting and valuable for everyone since anchoring is such an important and difficult part of cruising.

In this thread we are discussing people's experience with Mantus anchors, positive and negative. Besides real life experience, discussion of the theory of how these anchors work is very valuable and very welcome. There has been some very interesting criticism of the strength of the Mantus shank, and of whether or not Mantus anchors will work or not with the roll bar removed. These discussions have gotten down to a level of detail which involves engineering calculations and how to measure beam strength and so far -- this is great stuff.

So please people -- discuss away. All points of view are welcome. What you MUST avoid, however, is provocation of conflict and personal attacks. You must keep you comments polite, respectful, factual. You are absolutely allowed to disagree with each other. You can say just about anything you want as long as you show proper respect for each other and behave like adults. This thread is on "hot topic" and will be strictly policed for rude or aggressive behavior.

I would also like to underline that there is a big difference between a naked assertion, and an argument supported by facts and logic. Everyone is entitled to an opinion, even an uninformed opinion, but don't confuse it with a worked-out argument. If you want to refute something someone has said, the structure of your post should not be "you're just wrong" (and all the more not "you're just wrong because you're an idiot" or "you're just wrong because you are a conspirator against Joe Blow" or "you're just wrong because you're trying to foist inferior goods on us"). It should be: "this particular thing you said is not correct, because x, y and z", based on facts and logic. If, for example, you want to say that the Mantus shank is too weak, it would be really good if you would show the objective basis upon which you came to that conclusion. Inevitably, we will have to do proper engineering calculations to say anything meaningful on that subject. I know we have a number of CF members who have the knowledge and skill to do them.

I am personally interested in the shank strength discussion -- I don't think we've even scratched the surface of how to calculate it. I am not an engineer, so I will sit back and watch those more knowledge than I figure it out. Engineering calculations are an objective thing -- someone will make them, and others will try to find flaws in them. Eventually the objective truth will be revealed. That's an absolutely normal and actually extremely useful discussion.

I think shank strength, as interesting as it is, needs to be kept in perspective of the comments of Noelex earlier in the thread -- nearly all shank-bending situations occur when anchors are raised, so this will not generally be an immediate safety issue. Nevertheless, of course, no one wants to have his main anchor out of commission in the middle of a cruise, because the shank couldn't stand up to some side loading when lifting the anchor out of a difficult bottom. By keeping in context I mean -- let's not get carried away, let's not get hysterical about it. It's probably not the direct safety issue that reliable holding, and reliable resetting are.

Cheers.
Thank you and all of the moderators for reopening the thread.
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