Rocna Anchor Fail

[Dockhead]

By the way, the grade of steel is covered not only by general principles of law but by Rocna's own warranty:

"Faulty Product

If the anchor is defective or fails to conform to its specifications then those situations are covered under the separate terms of our Lifetime Warranty. In either case this Money Back Guarantee is not applicable.

In plain English: The Money Back Guarantee does not apply to faulty product. If your anchor has a defect or fails to conform to its specifications, refer to the Lifetime Warranty."

. . .

"Coverage
Rocna warrants that the product will conform to its specifications and will be free from material defects in and failure of material and workmanship from the date you purchase the product.
In plain English: This means the warranty covers standard things like the grade of steel and welding quality, and will not fail when used as intended."

[Kettlewell]

In a normal bottom the forces required to turn in the anchor in the sea bed are much less than what will bend a shank of any reasonable material.

This may be true if the shank is built strong enough, but I personally saw a bent shank hauled out of the water on a boat anchored next to me in the Keys after an overnight frontal passage. Note, this was some sort of Bruce knock-off anchor, but adequately sized for the boat, just not manufactured of proper stuff. The shank came up bent nearly 90 degrees. Holding ground was pure sandy mud--no rocks within a mile of where we were. It wasn't a particularly violent front either, just 20-30 knots maybe. The holding ground was excellent, and apparently instead of the anchor pivoting, the shank bent. So, it can happen if the material isn't up to the job. I wrote an anchor survey about six years ago based on walking the docks at the mouth of the Panama Canal and I noted at the time that a significant number of the knock-off anchors were visibly bent or damaged, but very few of the name-brand originals.

[estarzinger]

Originally Posted by GMac

I don't know what the effects or possible downsides of the noted 'appear to be casting defects' maybe but my laymans head is thinking, not good at all.

I agree. A low quality casting QA could mean that some few random anchors have almost no strength at all. That's potentially much more troublesome than the lower quality steel used.

Originally Posted by Capitain Mike

I
Manson . . . . Ned Wood could not do enough to help me. Polite, efficient, helpful and understanding, In my eyes Their Service makes them stand out above them all.

Ned is a terrific guy. He does not get the recognition or credit he deserves.

[barnakiel]

Originally Posted by atoll

well in all fairness to the anchor,to bend the shank like that the anchor must have exccelent holding power

No. The anchor probably got wedged into something solid and then pulled sidewise. Possibly in an attempt to retrieve it.

Holding power is not defined like that.

Probably ask the poster of the picture how things happened.

What I like, though, is the shaft got bent, not broken. The question, naturally is, how early it happened?

b.

[IdoraKeeper]

Somehow I know this is all Boatman's fault. If he would just stop advocating fancy anchors we could be focusing on LED nav lights using Ipad navigation.

Todd

[S/V New Sensation]

Disclaimer I own a Rocna 25 (and I love it but more important my wife loves it) built in Canada; sets faster than any anchor I have ever owned and holds in everything I’ve been in (YRMV). The reason I did not buy a Manson was the shank design, the Rocna fit my boat the Manson would not without giving up some teak trim (I’m all about the aesthetics). I also got the Rocna on sale so the price difference was minimal and really didn’t play into my decision anyway.

Another disclaimer, it has been a lot of years since I got my engineering degree I did not specialize in materials and I have not applied that knowledge in years; so like others have said my number conversions to units I learned in school could be wrong. First no matter how you look at it the Manson shank in the test has higher yield (120-125K psi) and ultimate strength (127-128K psi) steel than the Rocna. The number Rocna has on the web site for the shank steel is 800 MPa steel (which I assume is ultimate) this comes out to approximately 116K psi by my reckoning. The Manson test samples from the shank area both exceed this. I think Manson made their point they do not use inferior steel.

The large Rocna is approximately 78K yield and 106K ultimate. The smaller Rocna approximately 67K yield and 85K ultimate. Neither of these meets the 116K the web site talks to (71-91% of claimed) but I don’t think this is “mild steel” where (if memory serves) yield is closer to 30K and ultimate is around 60K psi. I also don’t think it should be called “inferior steel” but it certainly doesn’t test out to meet their web site number. I agree with others the more concerning issue is the casting defect in the blade area of the one sample and the relatively large variation in numbers for the other test samples for the Rocna which “could” be some casting issue vice the quality of the steel used in the casting.

I personally don’t read too much into the test of the steel. Unless you have all the design criteria for the shank, blades attachment methods (welds etc.), and can make a lot of assumptions about where and how loading will occur, I don’t think you can say this data is predictive of how or when either anchor might fail in use (at least I know I can’t). But again I think Manson made their point they do not use inferior steel.

[S/V Alchemy]

I may have said this before here (because similar threads abound across the "sailing forum spectrum"), but you'd be hard pressed to call the Rocna a crappy design or a bad anchor. Thousands are successfully in use; it's manifestly a workable design.

But the hype doesn't appear to match the reality, and, like people maintained about certain dead dynastic politicians: if they lied about that, what else have they lied about?

Marketing always walk a fine line between product advocacy, straight information, and sweet talk. Particularly with critical safety equipment, the claims made must be verifiable, and the slagging of the competition, especially when they have as good or better a track record than one's own product, should be kept, in my view, to a minimum.

Rocna, again in my view, has not met nor appears to now be meeting those marketing objectives. They make a good anchor that leaves a bad taste. There are alternatives, demonstrably as good or better, that leave no taste at all, because they have not made questionable claims or run low-level campaigns of negativity.

Rocna made their choices and must live with their consequences. I'm getting a little sick hearing about them, really. It does nothing to enhance my cruising experience.

[bigwow]

I think there must be something wrong with me, perhaps I’m just an old fart, but I seem to manage with my old and trusted CQR.
There I’ve said it, bit like the AA

[S/V Alchemy]

Originally Posted by bigwow

I think there must be something wrong with me, perhaps I’m just an old fart, but I seem to manage with my old and trusted CQR.
There I’ve said it, bit like the AA

If it works when you want it to, where you drop it and (most importantly, I feel) using the method you feel is safest (bridle, snubbers, sufficient scope), why change?

The second/spare/tandem/stern anchor is up for grabs, however. Most of us don't carry just one.

[KnuckleDragger]

Long time lurker here finally spurred into action. Just two weeks ago bought a Rocna 20 and WAS quite pleased with myself until the recent pooh hit the fan.

Now more confused and suspicious than anything.

Of both sides.

One thing that I have noticed and have not seen anyone comment on here or elsewhere (I read them ALL!!!) is why the "Manson" test was conducted eight days AFTER the "Rocna" results were received? Wouldn't you think that if you were hauling your newly purchased Rocnas to the lab that you would just toss a couple of your own in the back as well? Or maybe you want to see how your arch rival tests out first in case you need to come up with something "special". I'd have rather seen a receipt for a couple of random Mansons from the same store.

Like I said...I'm suspicious.

Of both sides.

[CSY Man]

I’m just an old fart, but I seem to manage with my old and trusted CQR.

I am an old fart as well and as such have dragged many times with my old 35 lbs CQR.
Got tired of sitting up all night on anchor watch.
Sold the thing on ebay and bought a better anchor.

Sleeping good every night these days.

[boatman61]

Originally Posted by CSY Man

I am an old fart as well and as such have dragged many times with my old 35 lbs CQR.
Got tired of sitting up all night on anchor watch.
Sold the thing on ebay and bought a better anchor.

Sleeping good every night these days.

From one old fart to another coupla farts..... Greetings Farts....
CSY... I hope it was something decent like a BRUCE................

[Pete7]

Originally Posted by KnuckleDragger

Long time lurker here finally spurred into action. Just two weeks ago bought a Rocna 20 and WAS quite pleased with myself until the recent pooh hit the fan.

Now more confused and suspicious than anything.

Of both sides.

I wouldn't worry, as S/V says they are a good design and there are alot of happy owners who swear by them which probably the ultimate test of any anchor, people using them. If they didn't work you would certainly hear about it.

Pete

[LakeSuperior]

Originally Posted by Pete7

I wouldn't worry, as S/V says they are a good design and there are alot of happy owners who swear by them which probably the ultimate test of any anchor, people using them. If they didn't work you would certainly hear about it.

Pete

Drawing conclusions from voting that is based on weak or poorly understood empirical data is dangerous for a number of reasons (consider that we used to burn witches).

1. 99% of anchoring is not in conditions which would stress the anchor to point where the user could say that my anchor A failed but anchor B would have held or not deformed or reset, etc.

2. Based on 1. the sample size for anchor failure cases that would differentiate designs would be extremely small and these would be the only cases you would hear about.

3. How could a normal user tell what kind of load made an anchor fail? Perhaps all anchors would have failed in that given situation, or most anchors would have, etc.

4. Consider the variables: scope, bottom type, wave impulses, windage, boat mass, wind speed, boat tacking on the rode, load angle on the set, anchor mass, etc.

Consequently, it would be easy to draw the wrong conclusions based on a small number of incidents where all the variables are not known or well understood. Add to that a piling on effect of the posters and marketing hype by manufacturers and the water gets muddy quickly.

Basically, I and others are suggesting a program of research that would answer the fundamental questions that cannot be answered through casual anchor use.

[GordMay]

Greetings and welcome aboard the CF, bigwow, and KnuckleDragger.