It's True! The Mantus 65-lb. hooks first time, everytime.

[evm1024]

Originally Posted by Mantus Anchors

Our shanks were made of A36 mild steel but we have recently switched to a higher strength ASTM 514 alloy ... We never had a claim for a bent shank yet - the shank is designed to accommodate "violent storm, 60+ kts, loads for its respectively sized boat. In a nominal configuration, shank parallel to rode, the shank does not fail or bend. The most common way to bend a shank is by side loading bc stuck in rocks or something similar. But we listen to our customers and strive to bring the best product available on the market. Any customer who wants his Mantus Shank switched to the new ASTM 514 material shank should only call us...
Greg
On another matter I truly believe that when pictures appeared of bent Rocna shanks on the web it was mostly sabotage, Rocna anchors never offered any danger to the end consumer. The different grade of steel used, surely needed to be disclosed but Rocna still provided a premium product that in its setting ability was superior to anything else on the market and was definitely rugged. The pictures of bent shanks I suspect were mostly staged,,, Anchor shanks bend on occasion but pictures of pretzel shanks that appeared online clearly did not result from in situ use...

Humble opinion, but I play with anchors full time....
may be its worth something

That is a very good move and good to know Greg. (I'm assuming that you meant A514)

Ever think of making a special order shank out of higher strength steel (e.g. Endura) for those going to high lattitudes (or rocky areas)?

For those who do not know ASTM A514 is the equivalent of Bisplate 80.

For those who want a nice read on high strength steels take a look here:

http://bisalloy.com.au/application/a...02012-2013.pdf

[evm1024]

Actually as long as I am thinking about it the Mantus with its bolt on shank could make a great workd cruising anchor. One could carry a spare shank and if you ever did bend the shank just bolt on your spare and get a replacement sent. No down time.

[JonJo]

ASTM 514 is difficult to weld, but skilled welders, those who might make boilers, would know how to do it. It would be easy to check, buy a Grade 5 and 8 construction bolt. File off the galvanising on the shank and sandwich a ball bearing between the bolt head and shank - compress as hard as you can in a vice. You will develop an indentation, roughly proportional to the strength of the steel. But quicker to ring Greg, and I'd do it next week.

ASTM 514 has a yield strength about 40% higher than the steel the metallurgical lab identified was used on the sample tested. The sample tested appears to be made with a steel better that A36, the sample dates from Jan/Feb this year (I recall). If it has been decided to beef up the shank has any move been made to beef up the bolts, they are Grade 5 construction bolts, the lowest quality considered to be high tensile and if the shank was deemed not strong enough I might guess the bolts were chosen the same way.

Why on earth was an A36 steel specified - the maths is very simple, why do I get the impression the lessons of Rocna were simply ignored. Greg, you have been aware of shank strength doubts for months, why so long, why keep it a secret.

The maths is easy:

Increasing steel strength from, assumed, 550 MPa YS steel to a 780 MPa steel YS will increase the strength of the shank of the 15kg model from 180kg to 255kg. Rocna offered to replace any and all anchors that were made with a low specification steel and had a shank strength of 246kg for the same model.

If Mantus decided to change steel, for safety reasons - do not tell me they are altruistic, where is the, widely publicised, recall notice. (With no disrespect I do not call an offer to replace tucked in to a thread here a recall notice). But maybe Mantus will have a large notice at Fort Lauderdale.

Even with the new steel the anchors are an accident waiting to happen.

The suggestion that the anchor will always land the right way up simply adds further insult to insult. Are cruisers that gullible.

Someone has asked if the anchor they bought at the Annapolis show had the better shank - the fact that Mantus was unwilling to confirm immediately that it was a ASTM 514 shanked model suggests they are still moving old stock (and maybe the new steel shanked models have not yet arrived?)

And Greg, I had 2 Rocna anchors tested in NZ by an owner who bent one in a thunderstorm in the Caribbean and one between the Caribbean and NZ. Both were a 420 stee,l neither was bent intentionally - please keep firefighting to your own fires. I have chapter and verse, other anchors, other places on the Rocna debacle and you look to be getting closer and closer to copying them. Suggesting it was some grand conspiracy makes you look very silly, even Peter Smith never made such an imaginative suggestion. It almost sounds as if you have based your steel choice on your idea it was all set up! As an anchor maker you should have the 2 relevant and detailed articles in Yachting Monthly on Rocna, I strongly suggest you get them out and read them.

Jonathan

[Rhapsody-NS27]

I just put together the 25lb anchor I bought while in Annapolis. Everything looks fine and looking forward to switching out the one currently on the bow.

Thanks Greg/Mantus

[hpeer]

John,

I acknowledged your analysis.

I did NOT say bigger is better.

What I was talking about is VALUE.

Your argument starts to sound like ...." You should only but the strongest anchor possible." But since bigger anchors are stronger then it is you who is making the " bigger is better" argument.

Real people have limited budgets. Would I like a 125lb Ultra or Spade? Sure! Can I afford one? No way.

Even given your analysis .....
1. The Mantus will provide better holding PER DOLLAR.
2. 99.9% of my anchoring situations will not stress the Mantus.
3. I don't care if I bend the shaft, I care if the shaft BREAKS. In such a situation it is likely something else beside that bloody big shaft will break first.

Again, I understand your analysis. It is but ONE of the factors involved. Each of will come to different conclusions based upon our situation. And each one may be right. It is situational.

[JonJo]

hpeer,

You are correct in that the shank will not break. Shanks breaking off anchors is about as rare as chains breaking.

Best wishes and good luck

Jonathan

[sabray]

It would be nice if mantus could give a clear description of how and what the parts are made of. Fortress not only gives a warranty but also clear description of what you are buying. Not sure I understand at all the tech parts. No idea now what Mantus is selling. I like the approach but not being clear on method and material is going to hurt. Why I have a old Bruce with no rust. A newer Manson with some rust. A Luke with no rust but sitting at home. And a fortress on my stern rail. All very good anchors for appointed jobs. All these anchors have done very well holding. I think without testing the actual make up what I got is what I bought. Not sure what I get if I bought a mantus. That's not good for mantus. So mantus though I like your position lets hear. Of what and how are you making these anchors?

[Shawn67]

"If Mantus decided to change steel, for safety reasons - do not tell me they are altruistic, where is the, widely publicised, recall notice. (With no disrespect I do not call an offer to replace tucked in to a thread here a recall notice). But maybe Mantus will have a large notice at Fort Lauderdale."

Why would a production change warrant a recall?

This isn't the same as the Rocna situation. Rocna specified what metal they were using, but didn't deliver on that specification. That was false advertising which also likely could have set them up for serious liability lawsuits due to fraud.

Shawn

[colemj]

Originally Posted by JonJo

Shanks breaking off anchors is about as rare as chains breaking.

Probably better said as breaking a Chinese anchor is about as common as Chinese chain breaking.

Mark

[JonJo]

Maybe I can put this simply

Rocna, Delta, Excel and Supreme shanks all have a similar strength, for the same size anchors. The manufacturers of these anchors have something like a combined 70 years of experience. There might be overkill but its the strength they all choose.

Rocna used a lower grade steel, for a numbe of months, many of these anchors bent. Rocna returned to a steel that provided their anchor shank with a strength similar to their 'peers'.

Rocna offered to replace any anchors made during the offending period.

Mantus have made no claim about the strength of their shanks. However anchors are deemed a safety item by most marine bureaucracies and many demand that an anchor be carried. Most yachtsmen expect items they buy to be safe and reliable.

The original shank on the Mantus has a strength much less than half the strength of Delta, Rocna,Supreme and Excel and the new shank is little difference in strength, the difference is probably not descernable, to the anchors shanks that Rocna offered to replace.

It has been suggested that one desirable feature of the Mantus is its low price - it is quite possible to increase the strength of the Mantus shank to be the same as the aforementioend 4 and it would cost very little extra, maybe $10. There would be a need for testing, to check the setting characteristics etc - but its easy. The answer is in my previous posts. its not rocket science.

Changing would take time and sadly there ought to be an additional cost in replacing the 'old' shanks. In the meantime it might be wise, morally correct?, to issue some form of cautionary note.

People on this thread reiterate how nice the people are at Mantus. I sadly have never met any of them so I tend, to ignore that emotive part, and measure them on their product and how they handle it.

Good luck and best wishes to you all

Jonathan

Jonathan

[JonJo]

Originally Posted by colemj

Probably better said as breaking a Chinese anchor is about as common as Chinese chain breaking.

Mark

I have forgotten but where are these anchors made?

There is nothing wrong with product made in China - its the specification and quality control that are critical. I am not aware of Rocna's (under CMP) nor CMP chain failing - but correct me if I am wrong.

Jonathan

[JonJo]

Its 9pm on Sunday night in Florida and the American weekend is basically over. I had suggested someone, anyone - take the roll bar off their Mantus and try it. Did anyone have the time?

I am quite happy to be shown I am a complete idiot and know nothing about anything of which I post. I am quite happy to be shown to be a complete ******* - out to destroy the reputation of a lovely company and its staff on no basis nor foundation.

Did anyone take up the challenge and make videos to show that the roll bar is superfluous.

Though it may seem the opposite I'd like Mantus to pull through. Simple, cheap, innovative design - everything needed to keep the industry on its toes. Spoiling entrepreneurialism with what, I (and I seem to be very alone) consider, unnecessary sub-standard quality and misleading video totally undermines what could have been a product that looked to be able to scare the pants off the competition.

Take care

Jonathan

[Shawn67]

" Rocna offered to replace any anchors made during the offending period."

Actually, it was West Marine that made that offer as part of their "No Hassle Guarantee." Not Rocna.

http://content.westmarine.com/docume...-%208%2001.pdf

West Marine update » Rocna Anchors

Shawn

[JonJo]

Originally Posted by Shawn67

" Rocna offered to replace any anchors made during the offending period."

Actually, it was West Marine that made that offer as part of their "No Hassle Guarantee." Not Rocna.

http://content.westmarine.com/docume...-%208%2001.pdf

West Marine update » Rocna Anchors

Shawn

Shawn,

One must be nice to people and I was giving Rocna the benefit of the doubt (and omitted WM) as I did recall, vaguely, they (Rocna) made some sort of offer on the CMP or Smith websites. But you are correct in that West Marine did offer under their no hassle guarantee. I was not trying to denigrate WM.

Jonathan

[Mantus Anchors]

Ok I am not sure even where to start.... there are so many accusations:
First and for-most you accuse me of not being altruistic that hurts
Than there is a question of my integrity, my lack of concern for safety, corn flake shanks, grade 5 bolts...., and then there is the recall!!!!
I took a couple of Valium, and chased it down with A VASE of Mount Gay to try to address your concerns...:


I do feel kind of altruistic, in fact and I do want to reiterate some truths.

Example one, shank aligned with the rode:
If you end up in a violent storm and are using our anchor, the shank, if loaded nominally (rode aligned with the shank) has a safety factor of greater than 500% against yield. Specifically, ABYC expected load on a 40 foot boat in a violent storm (60+ kts) is 4800 lbs. Assuming that boat is anchored on a 45 lbs Mantus and we triple that load to 15,000lbs, no area on the shank will come even close to yield (bending), not to mention ultimate breaking strength.

Example two, shank is laterally loaded:
So in the possibility that the anchor is permanently stuck in rock such that it can not re-align itself or displace at all, AND shank aligned vertically to ground AND the boat is pulling with perfect 90 angle at a shallow scope...
The expected load on a 40 foot boat in 30 knots is 1200 lbs- this will indeed bend our mild steel shanks AND the shanks of all our competitors. So somewhere between 20-30 knots with the given scenario above is the narrow window that differentiates us from shanks made of the best steel possible. This, apparently, is where we are "the disaster waiting to happen".
I agree a bent shank is very inconvenient but if a customer happens to encounter such an event replacement parts are covered by our warranty as previously stated.

Example three, same (60 kts storm 40 foot boat) conditions, the expected rode load according to ABYC is 4800 lbs. Applying double this load (9600 lbs) to a 45 lbs Mantus anchor and using a standard tension shear bolt interaction analysis, gives a margin of safety of over a 800%. (again assuming the loads of 9600 lbs... double what ABYC suggests would be an expected load on a 40 foot boat in a 60 kts storm) Hardly a "disaster waiting to happen", more like VERY conservative engineering.

By the way compare this to chain strength. The same load (9600 lbs) applied to HI TEST 3/8 chain (best case scenario for attaching the anchor to the boat) has a WLL of 5400 lbs and UTS of 16,200 lbs. Nowhere near the margins of safety on the bolts.

As to the warranty, I think that our customers appreciate the rather "altruistic" attitude of going beyond what is typical for most manufacturers these days by replacing and shipping replacement parts at our cost....
another Valium chased with now VODKA (mother RUSSIA will be proud)
by the way the engineering team is drinking too!

Not sure what fires you are alluding to. We have always been very transparent about the details of our products, with information available on our website plus willingness to help out any potential customer with fit, function or sizing questions any day of the week.

As far as the transition... Our current stock is A36 Steel same as the anchor I sent you earlier this year, and we are currently transitioning to A514 material and customers will have a choice. I believe I told you of our intent to change the shank design last Feb.... I am not sure if you are just forgetful or purposefully disingenuous.

It is very difficult to design an anchor for all potential contingency situations. We have optimized the Mantus for setting and holding ability in even hard-packed clay/mud or grassy/weedy areas. This means a large, robust fluke area, light weight roll-bar and a shank that can accommodate all nominal conditions with plenty of margin. If a customer wants an anchor with extra strong shank we would recommend a Bruce or CQR, of course then, you'd end up compromising on setting/holding. A modular design permits customers to carry spare parts. We believe the Mantus is the best choice for a cruising anchor - a great performing anchor at a reasonable cost.

Thank you for giving me an opportunity to share the benefits of Mantus with the community.... It is always a pleasure to talk about our BABY

Greg now very, very tipsy