Rocna Size

[boatman61]

Originally Posted by CAELESTIS

Something is just not quite right with this Rocna allegation. So far, it has been very one sided.

I think there is more to this issue.

Actually its swung the other way...
3-4mths ago they were the best things since sliced bread... love was in the air and folks who used 'lesser' ground tackle like Bruces were treated like morons...
now everyone who bought one is dumping em... folks are fickle....

[KnuckleDragger]

Originally Posted by estarzinger

regarding punch tests . . . two questions

As background, a few facts:
Hardened tool steel Brinell hardness = 600-1500HB
Bisplate 80 (rocna specification) Brinell hardness = 255HB
Bisplate 60 (general grade apparently used in tested anchors) = 210HB
A36 (mild steel) Brinell hardness = 150HB

So, my two question(s):
(1) would you not get a dimple even in the specified B80 steel if you hit it with a tool steel punch?
(2) would it be possible by eye to distinguish the dimple in B80 steel (speced) from the dimple in B60 steel (apparently used in tested anchors) given their harndess numbers are only 20% different?

As some of you may remember, I returned my Rocna last week and ordered the same size Supreme. It's now sitting on my bow roller. Very quick and courteous service from West Marine. Just out of curiosity I smacked it with a center punch. Medium firm blow. Left a definite indentation much like that left in the Rocna (used a 16 penny nail though). I don't feel the punch test is a very definitive test.

[s/v 'Faith']

Originally Posted by KnuckleDragger

As some of you may remember, I returned my Rocna last week and ordered the same size Supreme. It's now sitting on my bow roller. Very quick and courteous service from West Marine.


Just out of curiosity I smacked it with a center punch. Medium firm blow. Left a definite indentation much like that left in the Rocna (used a 16 penny nail though). I don't feel the punch test is a very definitive test.

So you used a nail on the Rocna, and a centerpunch on the Manson and since they both showed a mark you think the anchors are the same?

I am thinking you missed the point of this. The nail is mild steel, the punch is high carbon.

[skipmac]

Originally Posted by KnuckleDragger

As some of you may remember, I returned my Rocna last week and ordered the same size Supreme. It's now sitting on my bow roller. Very quick and courteous service from West Marine. Just out of curiosity I smacked it with a center punch. Medium firm blow. Left a definite indentation much like that left in the Rocna (used a 16 penny nail though). I don't feel the punch test is a very definitive test.

I think you have too much variation in your method and tools to get any realistic results. To get an accurate hardness test you would have to use a method that gives the same force with each blow and use the same size and hardness device to make the dimple. Then a way to accurately measure the size and depth of the dimple. Plus I think mulitiple tests would be required to rule out localized differences in the surface hardness and any other variables.

As Estarzinger pointed out, the difference in hardness of the steel Rocna specs vs the steel that it is claimed is used by the factory is not that great so accurate testing would be required to tell the difference.

I still do not believe I have seen anyone address the issue of whether or not the difference in hardness would make a significant difference in the actual strength of the anchor in real world use.

[Delfin]

Originally Posted by estarzinger

regarding punch tests . . . two questions

As background, a few facts:
Hardened tool steel Brinell hardness = 600-1500HB
Bisplate 80 (rocna specification) Brinell hardness = 255HB
Bisplate 60 (general grade apparently used in tested anchors) = 210HB
A36 (mild steel) Brinell hardness = 150HB

So, my two question(s):
(1) would you not get a dimple even in the specified B80 steel if you hit it with a tool steel punch?
(2) would it be possible by eye to distinguish the dimple in B80 steel (speced) from the dimple in B60 steel (apparently used in tested anchors) given their harndess numbers are only 20% different?

Depends on the hardness of the center punch. Knuckledragger used a 16 penny nail (very mild steel) to dimple his Rocna (do I have that correct KD?), and a center punch to dimple his Manson. Center punches are generally made of mild steel, with the tip tempered for hardness. That tempering can produce different hardness levels, and although B80 steel is a lot harder than B60, it is only barely considered 'hard'. For hard, try Bisalloy 500. To get around this, I used a reference steel of known hardness - a Japanese chisel. This was listed in the catalog as having the same Brinell 255 hardness on the shank as B80 so after dimpling the Rocna, I tried to dimple the chisel and dented the punch. The images for this are on post #62 of this thread.

Without having either a reference steel against which to measure the hardness of the center punch, or a center punch of known hardness, simply whacking an anchor shank isn't definitive.

An easy way to test hardness is by using hardness files. These come in different grades and you can use them to see which is harder - the file or the test piece. Every retailer of Rocnas should consider buying a set.

http://www.amazon.com/gp/product/B00...0ZPCSBRT0Y94X6

[avb3]

Originally Posted by skipmac

...
I still do not believe I have seen anyone address the issue of whether or not the difference in hardness would make a significant difference in the actual strength of the anchor in real world use.

That is because Rocna is determining what is required. It should not be up to users, but independent testing, that could definitiviely say that.

That being said, you want to buy, and you pay for an Escalade to pull your trailer.

The dealer delivers you a Yukon.

Both can pull your trailer, albeit the Yukon has less trim and lower horsepower.

Are you going to accept it because "it can do the job"?

[skipmac]

Originally Posted by avb3

That is because Rocna is determining what is required. It should not be up to users, but independent testing, that could definitiviely say that.

That being said, you want to buy, and you pay for an Escalade to pull your trailer.

The dealer delivers you a Yukon.

Both can pull your trailer, albeit the Yukon has less trim and lower horsepower.

Are you going to accept it because "it can do the job"?

The point of my question is not to suggest that one should accept a product inferior to that which was proffered even if "it can do the job". Strictly asked as a technical question motivated by a desire to be better informed of the critical aspects of anchor strength and whether or not it would meet my personal requirements.

[KnuckleDragger]

Originally Posted by s/v 'Faith'

So you used a nail on the Rocna, and a centerpunch on the Manson and since they both showed a mark you think the anchors are the same?

I am thinking you missed the point of this. The nail is mild steel, the punch is high carbon.

Please show me where I indicated that I thought that they were the same. The point (pun intended) is that smacking an anchor with something hard and sharp is going to leave a mark and not tell you much.

[avb3]

Originally Posted by skipmac

The point of my question is not to suggest that one should accept a product inferior to that which was proffered even if "it can do the job". Strictly asked as a technical question motivated by a desire to be better informed of the critical aspects of anchor strength and whether or not it would meet my personal requirements.

Good point.

I think it is incumbent on Rocna to provide that information.

They have been strangely silent.

Because of that, they now would have to provide very credible third party verification that is not subject to the obfuscation that they exhibited with the RINA "certification".

Once trust is destroyed, it is very, very hard to get back.

[Bash]

Originally Posted by hummingway

You used a wood chisel on an anchor? Where is the firing squad icon when you need it?

Amen, brother! The firing squad is too good for tool abusers.

[skipmac]

Originally Posted by avb3

Once trust is destroyed, it is very, very hard to get back.

Very true.

Originally Posted by avb3

I think it is incumbent on Rocna to provide that information.

They have been strangely silent.

A lot of silence from both sides. I keep thinking that somewhere there is another very large shoe that must eventually drop, with a very loud bang.

Wonder if there are lawyers somewhere watching all this and getting ready to start adding up some billable hours.

[Delfin]

Originally Posted by avb3

Once trust is destroyed, it is very, very hard to get back.

My guess is that the Bamburys, who bought the license from the Smiths for the Rocna will simply fold the company. This has been their pattern in the past, and since Holdfast, the Bambury company is literally run out of a room atop the garage attached to their house, folding this company will take about 10 minutes.

Although Craig Smith has irritated a great many people, I take my hat off to him for creating an image for a company with very few assets manufacturing a knock off of a Bugel, using the Internet to disparage and trash competitors, disseminate artful lies about their product resulting in the sale of quite a few anchors in the process. Manson has been making anchors since 1972 and is a real company. Fortress is now owned by the same folks who own American Bow Thruster and is a real company. Delta is owned by Lewmar. Rocna is a Potemkin Village erected by Craig and Peter Smith, and burned to the ground by Steve Bambury. When the Bambury's have moved onto their next adventure, the Smith's will get back the Rocna and a new, but tarnished company will probably emerge. Whether they will ever be able to retain their prior respect remains to be seen, but I very much doubt it.

[vet222]

I recently sent an email to Rocna as I am concerned I do not own what I thought I was buying:

"Hello,
I purchased a Rocna 20 in or around October 2010 from Vicsail in Perth Western Australia on the understanding it was manufactured to the highest of standards of quality and strength as stated on your website. I purchased it on the basis of trust in the Rocna product and the peace of mind that this trust and reputation I expected would deliver.
I am somewhat more than a little dismayed now to learn that Rocna anchors with "Rocna" cast into the foot are made in China, not New Zealand or Canada and that there is early evidence that the shank of these anchors are not to the high standard of strength as promoted by the Rocna company's product details.
Subsequently, this has rapidly eroded my trust and peace of mind with my Rocna anchor with respect to the possibility of anchor failure despite always striving to employ "best practice" anchoring techniques including but not limited to appropriate chain, plenty of scope for the given conditions, other quality fittings, rode, snubber etc.
I purchased my Rocna above all other anchors based on available information at the time and whilst it happened to be the highest cost anchor, the cost factor was of secondary importance to my peace of mind regarding such a critical tool for my boat.
That said, I would appreciate clarifications pertaining to a claim circulating certain blog sites that the shank of current Rocna anchors stamped with "Rocna" on the foot of these anchors, is of a lower grade of steel or hardness thereof than that specified by Rocna.
If there is any doubt as to the quality and/or strength of my Rocna anchor, what action do you necessarily advise I need take in order to ensure that I am not placing my boat or potential life at risk should there be a failure of my Rocna anchor?
Can you provide me with current test results that would substantiate that my Rocna anchor meets all of the high standards of quality and strength as stated by Rocna?

I anticipate your reply"

No reply initially but finally did receive an acknowledgment and I am eagerly awaiting an update on proof load testing. How this info will apply to my anchor I am not sure at this stage. I may be left wondering whether test anchors used for their testing purposes will be different to the anchor I bought. Also, no indication of steel specification at this time:

"Hi Steve,

We are so sorry for the delay in responding to you – we have been backed up here following a tornado that swept past our office and took our internet lines with it (see http://www.rocna.com/news/rocna-offi...freak-tornado/ – not a common occurrence in New Zealand.)

Thank you for contacting us directly, as there is a lot of confusion, incorrect speculation and misinformation to be found in the discussions online regarding Rocna Anchors.

Our primary concern is to ensure all Rocna anchors are undeniably fit for purpose and safe and we have seen no evidence from real-life anchor use to indicate this is not the case. We are confident that all Rocna anchors meet requirements, and we have comprehensive proof load testing underway to verify this.

We have made a note to send you the results of testing as soon as it becomes available. If there is anything else we can do for you in the meantime, please don’t hesitate to contact us.

Kind regards,


Rocna Anchors"

[sailorboy1]

So they sent you a note saying they would forward you the testing info when it becomes available; is this code for saying they currently don't know the answer to the question!

[vet222]

That'd be my take on it.