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Delfin
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Can't.* I still have the back 40 to plant.
Rocna revealed
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Delfin
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Since this is a topic of general interest on a vital piece of safety equipment, Im posting the below to the 4 sites I participate in, not to beat up on Rocna, but because most everyone with a boat needs an anchor, and sometimes ones boat and the safety of the crew depends on the integrity of the anchor manufacturer.* By way of full disclosure, I use a 176# Bruce type Claw on Delfin, and it has served me well, so far.* I have zero financial interest in any anchor manufacturer or marine distributor.
I recently purchased a Rocna 22# anchor for testing because it seemed as if there were many opinions on the strength of this anchor, but not enough objective data to make a final conclusion.
To test my Rocna, I took it to NW Laboratories, who have been performing metal testing in the Seattle area since 1896.* An initial hardness test was performed, since tensile strength can be correlated to hardness, and on the basis of that test the anchor was submitted to full testing to determine whether the steel used matched the grade of steel advertised by Rocna.* By way of background on the importance of steel quality, here is what Rocna has to say about the steel it uses:
The shank on any anchor is a common failure point, normally bending when a high lateral load is applied (for instance, when the anchor fouls on a submarine obstacle and is jammed). For this reason, the shank on the Rocna is a high tensile quenched and tempered steel, with a grade of around 800 MPa. Its pure resistance to bending is around three times that of mild steel. This adds to the price of the anchor, but compromising this strength is not something we would entertain.- http://www.rocna.com/kb/Anchor_materials
In this, Rocna is stating that their anchors will be more expensive than cheaper anchors because they want to avoid a common failure point, which would be the bending of anchor shanks with steel that had an Ultimate Tensile strength less than 800 Mega Pascals (MPa), or 120,000 psi.* This type of steel meets the standards set in ASTM A514, has a Yield Tensile strength of 720 MPa and is available from Bisalloy Steel in Australia, as well as other companies worldwide, including sources in China where the Rocna is made.
In discussing why Rocna doesnt manufacture an aluminum alloy anchor, they expand on the importance of and the reason for using 800 MPa high tensile steel in their anchors:
For example, an aluminum shank would not be able to possess the same tensile strength as the 800 grade steel we use without being significantly thicker, which would then affect setting performance in hard sea-beds.* http://www.rocna.com/kb/Anchor_materials
In other words, without high tensile 800 MPa steel in the shank their anchor would have to be thicker to withstand the loads typically imposed during normal usage, and this would affect the balance of the anchor adversely when it comes to setting ability.
Finally, in the Users Guide that comes with each Rocna there is a statement that underscores how the Rocna anchor is superior to its competition because it addresses one of the shortcomings of most anchors weakness in the shank:
"The Rocna was designed to address the limitations shared by all older and most newer anchors available. These designs suffer from .. "insufficient strength in the shank or other load bearing components."
Clearly, Rocna believes that the unique design of the Rocna anchor requires the very best components, and competitive anchors that do not meet Rocnas standards are suggested to be inadequate due to inherent limitations.
Attached in the first image below is a summary of the test results from NW Labs in the form of a summary comparison of the Rocna 22# I purchased to its closest analog the Manson 25# Supreme.* The test itself is in the second image.* I chose the Manson to compare to mine for a number of reasons.*
First, Manson says that they use 800 MPa, 120,000 psi steel in their anchor shanks, and have published tests confirming this.* The link to those test results for the Manson 25 is here:* http://manson-marine.co.nz/SitePages/Supreme_Anchor_high_standards/11-037%20Tensile%20Manson%20Anchor%2018Apr11VB.pdf
The second reason is that the Manson has a similar design to that of the Rocna, and shows equivalent holding power in most tests.*
The third reason is that the Manson is available in North America and the U.K.* I dont have the prices of the Manson in the U.K., but in the U.S., they are significantly less expensive than the Rocna.
The final reason is that according to Ned Wood, the manager of Manson Honestly, I have never seen or had a complaint from a customer about a bent Supreme Shank, ever. Over 12,000 sold and I am fairly sure I would have heard of something but never have heard, nor has anyone here.* Since we have pictures of bent shanks on the Rocna, something is clearly going on, so I thought a careful comparison between the two products should shed some light.* I cant verify whether Mr. Woods statement is true, but I did ask him if I could quote him, so I assume it is the truth.*
While the test results are self explanatory, here is the punch line, in my opinion.* The Manson has about 14% more steel at the mid point of its shank compared to the Rocna.* Increases in cross sectional area proportionally increases resistance to lateral bending, so the Manson would be 14% stronger than the Rocna based on this measurement even if they used the same steel.* However, the Manson does use 800 MPa steel for its product, so the yield strength of the Manson is about 30% greater than the lesser steel used in the Rocna.* Higher yield translates directly into bend resistance, so on the basis of these two data points, the Manson is half again stronger than the Rocna at 2/3 the price.*
Because the shank of an anchor represents a lever, it is possible to put high loads on the shank with lateral loading that exceeds the yield strength (bend resistance) of the steel used.* The materials used in the Rocna have resulted in bent shanks; of the Manson - not so much.* Presumably Rocna well understands this potential failure point and how to avoid it with the right materials.* They didnt use those materials on my anchor, so it is de facto defective and a threat to my boat.* Not good.
With anchors available from manufacturers of integrity and great holding power made of appropriate materials, like Fortress, Sarca, Manson and others, it is hard to understand why anyone would pay more for less by purchasing a Rocna, especially since by their own definition, their product is unsafe.* Manufacturers of safety equipment should be held to a high standard of honesty, and retailers of those products should take care when promoting products that are known to be defective.*
For those who havent had enough punishment from this thread yet, Ill post the details of how the Rocna was tested, as well as other photos of the test subject.* Ill be returning my Rocna to West Marine for a refund based on the simple fact that it doesnt meet the specs advertised by Rocna.* I assume theyll give me my money back, but well see.*
I recently purchased a Rocna 22# anchor for testing because it seemed as if there were many opinions on the strength of this anchor, but not enough objective data to make a final conclusion.
To test my Rocna, I took it to NW Laboratories, who have been performing metal testing in the Seattle area since 1896.* An initial hardness test was performed, since tensile strength can be correlated to hardness, and on the basis of that test the anchor was submitted to full testing to determine whether the steel used matched the grade of steel advertised by Rocna.* By way of background on the importance of steel quality, here is what Rocna has to say about the steel it uses:
The shank on any anchor is a common failure point, normally bending when a high lateral load is applied (for instance, when the anchor fouls on a submarine obstacle and is jammed). For this reason, the shank on the Rocna is a high tensile quenched and tempered steel, with a grade of around 800 MPa. Its pure resistance to bending is around three times that of mild steel. This adds to the price of the anchor, but compromising this strength is not something we would entertain.- http://www.rocna.com/kb/Anchor_materials
In this, Rocna is stating that their anchors will be more expensive than cheaper anchors because they want to avoid a common failure point, which would be the bending of anchor shanks with steel that had an Ultimate Tensile strength less than 800 Mega Pascals (MPa), or 120,000 psi.* This type of steel meets the standards set in ASTM A514, has a Yield Tensile strength of 720 MPa and is available from Bisalloy Steel in Australia, as well as other companies worldwide, including sources in China where the Rocna is made.
In discussing why Rocna doesnt manufacture an aluminum alloy anchor, they expand on the importance of and the reason for using 800 MPa high tensile steel in their anchors:
For example, an aluminum shank would not be able to possess the same tensile strength as the 800 grade steel we use without being significantly thicker, which would then affect setting performance in hard sea-beds.* http://www.rocna.com/kb/Anchor_materials
In other words, without high tensile 800 MPa steel in the shank their anchor would have to be thicker to withstand the loads typically imposed during normal usage, and this would affect the balance of the anchor adversely when it comes to setting ability.
Finally, in the Users Guide that comes with each Rocna there is a statement that underscores how the Rocna anchor is superior to its competition because it addresses one of the shortcomings of most anchors weakness in the shank:
"The Rocna was designed to address the limitations shared by all older and most newer anchors available. These designs suffer from .. "insufficient strength in the shank or other load bearing components."
Clearly, Rocna believes that the unique design of the Rocna anchor requires the very best components, and competitive anchors that do not meet Rocnas standards are suggested to be inadequate due to inherent limitations.
Attached in the first image below is a summary of the test results from NW Labs in the form of a summary comparison of the Rocna 22# I purchased to its closest analog the Manson 25# Supreme.* The test itself is in the second image.* I chose the Manson to compare to mine for a number of reasons.*
First, Manson says that they use 800 MPa, 120,000 psi steel in their anchor shanks, and have published tests confirming this.* The link to those test results for the Manson 25 is here:* http://manson-marine.co.nz/SitePages/Supreme_Anchor_high_standards/11-037%20Tensile%20Manson%20Anchor%2018Apr11VB.pdf
The second reason is that the Manson has a similar design to that of the Rocna, and shows equivalent holding power in most tests.*
The third reason is that the Manson is available in North America and the U.K.* I dont have the prices of the Manson in the U.K., but in the U.S., they are significantly less expensive than the Rocna.
The final reason is that according to Ned Wood, the manager of Manson Honestly, I have never seen or had a complaint from a customer about a bent Supreme Shank, ever. Over 12,000 sold and I am fairly sure I would have heard of something but never have heard, nor has anyone here.* Since we have pictures of bent shanks on the Rocna, something is clearly going on, so I thought a careful comparison between the two products should shed some light.* I cant verify whether Mr. Woods statement is true, but I did ask him if I could quote him, so I assume it is the truth.*
While the test results are self explanatory, here is the punch line, in my opinion.* The Manson has about 14% more steel at the mid point of its shank compared to the Rocna.* Increases in cross sectional area proportionally increases resistance to lateral bending, so the Manson would be 14% stronger than the Rocna based on this measurement even if they used the same steel.* However, the Manson does use 800 MPa steel for its product, so the yield strength of the Manson is about 30% greater than the lesser steel used in the Rocna.* Higher yield translates directly into bend resistance, so on the basis of these two data points, the Manson is half again stronger than the Rocna at 2/3 the price.*
Because the shank of an anchor represents a lever, it is possible to put high loads on the shank with lateral loading that exceeds the yield strength (bend resistance) of the steel used.* The materials used in the Rocna have resulted in bent shanks; of the Manson - not so much.* Presumably Rocna well understands this potential failure point and how to avoid it with the right materials.* They didnt use those materials on my anchor, so it is de facto defective and a threat to my boat.* Not good.
With anchors available from manufacturers of integrity and great holding power made of appropriate materials, like Fortress, Sarca, Manson and others, it is hard to understand why anyone would pay more for less by purchasing a Rocna, especially since by their own definition, their product is unsafe.* Manufacturers of safety equipment should be held to a high standard of honesty, and retailers of those products should take care when promoting products that are known to be defective.*
For those who havent had enough punishment from this thread yet, Ill post the details of how the Rocna was tested, as well as other photos of the test subject.* Ill be returning my Rocna to West Marine for a refund based on the simple fact that it doesnt meet the specs advertised by Rocna.* I assume theyll give me my money back, but well see.*
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Delfin
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*
And for the truly geeky:
First, some term definitions from the above report.* Ultimate Tensile Strength (UTS) is the force required to break a standard sample of the steel being tested.* The first image below shows the shape of the standard sample which was subjected to a pulling force with the maximum force before breaking the sample recorded as the UTS.* Rocna advertises 800 MPa UTS steel, in my anchor, they used 697 MPa.
Yield Tensile Strength (YTS) is the maximum force a sample will absorb and still spring back to its original shape.* This is the measurement that matters to a boater, since resistance to side loading is a function of the YTS of the shank steel.* Rocna advertises 690 MPa YTS steel, in my anchor, they used 626 MPa.
Elongation is the percent the metal stretches before it breaks.
MPa are mega pascals, a metric measurement of force.* The English equivalent is pounds square inch.* 800 MPa equals 120,000 psi.
To test the metal, the lab cut a couple of small pieces out of the shank, embedded them in a bonding media and examined them under the microscope to determine which direction the grain of the metal ran. A picture of this test piece is in the second image.* Steel develops a grain along the direction flat steel plate is rolled.* It will have higher strength when the force applied is in line with this grain, so to ensure that the results we got were the maximum possible for the anchor, the direction of the grain was determined before cutting out the standard sample shown in the first picture.
The reference standard for the metal was what Rocna says they use 800 MPa steel.* This is the same steel that Manson uses, and it meets ASTM A514 standards.* The reference to Bisalloy 80 on the test is because it is 800 MPa, A514 steel and is used by Manson in their manufacture.
To accurately compare the Manson to the Rocna I consulted a friend who is a structural engineer to determine what changes in lateral bending force resulted from differences in the cross sectional area of the two anchors.*
The Rocna and the Manson are designed to have as much of the total anchor weight on the tip as possible.* To achieve this, the shank has to be fairly thin.* Even mild steel (YTS 400+ MPa) would work just fine under pulling conditions only since the chain or rope rode would generally break before the steel reached its YTS.* However, the length of the shank creates a lever that multiplies the lateral pulling in a side load to the point where the shank will easily bend unless it is made out of steel with a relatively high YTS steel.* The Rocna is designed for this higher grade of steel, but for reasons unknown Rocna has elected to advertise one grade and use another.* The result is an unsafe anchor, whose defects will remain hidden until the boater is depending the most on the integrity of the manufacturer.
Since I am not an engineer, I welcome any correction from more knowledgeable forumites on any mistakes in my analysis.
And for the truly geeky:
First, some term definitions from the above report.* Ultimate Tensile Strength (UTS) is the force required to break a standard sample of the steel being tested.* The first image below shows the shape of the standard sample which was subjected to a pulling force with the maximum force before breaking the sample recorded as the UTS.* Rocna advertises 800 MPa UTS steel, in my anchor, they used 697 MPa.
Yield Tensile Strength (YTS) is the maximum force a sample will absorb and still spring back to its original shape.* This is the measurement that matters to a boater, since resistance to side loading is a function of the YTS of the shank steel.* Rocna advertises 690 MPa YTS steel, in my anchor, they used 626 MPa.
Elongation is the percent the metal stretches before it breaks.
MPa are mega pascals, a metric measurement of force.* The English equivalent is pounds square inch.* 800 MPa equals 120,000 psi.
To test the metal, the lab cut a couple of small pieces out of the shank, embedded them in a bonding media and examined them under the microscope to determine which direction the grain of the metal ran. A picture of this test piece is in the second image.* Steel develops a grain along the direction flat steel plate is rolled.* It will have higher strength when the force applied is in line with this grain, so to ensure that the results we got were the maximum possible for the anchor, the direction of the grain was determined before cutting out the standard sample shown in the first picture.
The reference standard for the metal was what Rocna says they use 800 MPa steel.* This is the same steel that Manson uses, and it meets ASTM A514 standards.* The reference to Bisalloy 80 on the test is because it is 800 MPa, A514 steel and is used by Manson in their manufacture.
To accurately compare the Manson to the Rocna I consulted a friend who is a structural engineer to determine what changes in lateral bending force resulted from differences in the cross sectional area of the two anchors.*
The Rocna and the Manson are designed to have as much of the total anchor weight on the tip as possible.* To achieve this, the shank has to be fairly thin.* Even mild steel (YTS 400+ MPa) would work just fine under pulling conditions only since the chain or rope rode would generally break before the steel reached its YTS.* However, the length of the shank creates a lever that multiplies the lateral pulling in a side load to the point where the shank will easily bend unless it is made out of steel with a relatively high YTS steel.* The Rocna is designed for this higher grade of steel, but for reasons unknown Rocna has elected to advertise one grade and use another.* The result is an unsafe anchor, whose defects will remain hidden until the boater is depending the most on the integrity of the manufacturer.
Since I am not an engineer, I welcome any correction from more knowledgeable forumites on any mistakes in my analysis.
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hollywood8118
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Carl....
WOW!
I guess this pretty much is the final word on the Rocna, excellent presentation and information.
Thank you for all your work on this.. you have gone way above and beyond to find the truth,
Thanks Again
HOLLYWOOD
WOW!
I guess this pretty much is the final word on the Rocna, excellent presentation and information.
Thank you for all your work on this.. you have gone way above and beyond to find the truth,
Thanks Again
HOLLYWOOD
Nomad Willy
Guru
Carl,
It looks to me like the Rocna is only 15 to 18% weaker than specified. Did I read that correctly? It looks like almost everybody w a weak Rocna will survive anyway. So the situation is much better than I perceived. I thought Rocna was making anchors from mild steel. Mansons come about 15% heavier than spec'ed so your 25 pounder should be a 28lb anchor. I have a "15lb" Supreme that is 18lbs. HaHa* ..I wonder what West Marine is going to say when they see all the cut up parts. I'd still rather have an anchor that did'nt need to lay on it's side to set. I thought about becoming an anchor tester too so I'm glad someone has picked up the ball. What are you going to do next?
It looks to me like the Rocna is only 15 to 18% weaker than specified. Did I read that correctly? It looks like almost everybody w a weak Rocna will survive anyway. So the situation is much better than I perceived. I thought Rocna was making anchors from mild steel. Mansons come about 15% heavier than spec'ed so your 25 pounder should be a 28lb anchor. I have a "15lb" Supreme that is 18lbs. HaHa* ..I wonder what West Marine is going to say when they see all the cut up parts. I'd still rather have an anchor that did'nt need to lay on it's side to set. I thought about becoming an anchor tester too so I'm glad someone has picked up the ball. What are you going to do next?
JD
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*Very good report.
A question I have is. Would someone with a Rocna benefit from having a small*reinforcement plate welded on either side of the shank for it's entire length?
The point being you already own the anchor and it's resale has gone south, would $100 of welding save the anchor.
Or as Eric has said it has*a 15-18% weakness so just live with it and if it bends deal with it then.
-- Edited by JD on Wednesday 11th of May 2011 06:18:50 AM
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Delfin
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*I assume Peter Smith knows what he's talking about, and reducing shank weight by using higher quality steel ensures effective setting.* If you increased that weight, the anchor presumably wouldn't set as well.*
I think the important comparison is not what Rocna is to what Rocna claims, but to the Manson, which is half again stronger (and according to some very complicated calculations on another forum much stronger than that) for a lot less money.* To say that the Rocna is only 15% less strong than they claim and therefore ok is to me like saying that my Pinto is ok because it only bursts into flame when rear ended at 30 mph, not the 25 mph claimed by critics.*
sunchaser
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During my engineering, construction and metallurgical*career I have seen*and authored considerable *non-destructive testing and weighed the results as to how to relate these findings to the real world.Normally, a safety factor for all non-rotating things made of metal is used after factoring in seismic, vibration, wind loads, snow loads and anticipated corrosion.
An anchor is no different. So long as*an anchor's tensile, shear and bending moment "strength" can exceed the rode's WL by 150%, I'd not worry. On trawlers, the next size or two up in anchor weight should more than adequately give you the comfort you need - provided you have an acceptable rode and seek adequate shelter. The catch of course is to know what the actual, not claimed, load limits for the anchor are - which Delfin has discussed.
The rub here is Rocna's design works, but their advertising and fabrication claims got called. My senses were alerted to the Rocna BS on this forum a year or more ago when layman were touting the anchor's "strength"**as if it were gospel. Pray tell this would never happen to Manson.
An anchor is no different. So long as*an anchor's tensile, shear and bending moment "strength" can exceed the rode's WL by 150%, I'd not worry. On trawlers, the next size or two up in anchor weight should more than adequately give you the comfort you need - provided you have an acceptable rode and seek adequate shelter. The catch of course is to know what the actual, not claimed, load limits for the anchor are - which Delfin has discussed.
The rub here is Rocna's design works, but their advertising and fabrication claims got called. My senses were alerted to the Rocna BS on this forum a year or more ago when layman were touting the anchor's "strength"**as if it were gospel. Pray tell this would never happen to Manson.
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Delfin
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*Tom, it only takes about 600# of lateral load to bend the shank of the Rocna 10 I bought because of the lever arm of the moment of force (if I am saying that right).* Any anchor is stronger than the chain if all you are doing is pulling on it.* The problem with the new generation of anchors is that they do set well, so the likelihood of exceeding lateral bend resistance during sudden winds shifts is greater than for an older design.* I think for me, the issue here is paying more for a weaker anchor from a company that doesn't tell the truth about its product.* Even if the Rocna is 'adequate' under most circumstances, I'm still offended by deceptive trade practices.*
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Delfin, I agree with the Rocna shank length problem you noted. I looked at a Rocna 45KG and the shank was way too long to sensibly fit in the space I have for my current Bruce - from the anchor roller to the gypsy.*
You may want to look at the anchor setup on Sarah Sarah (Dashew FPB) being shown at Trawlerfest Anacortes. Darn it, I can't make it. I'm curious as to if they used a Rocna and what size.
You may want to look at the anchor setup on Sarah Sarah (Dashew FPB) being shown at Trawlerfest Anacortes. Darn it, I can't make it. I'm curious as to if they used a Rocna and what size.
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Delfin
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I looked at the Rocna on Sarah Sarah today, and it is a lunker - one of the NZ built units that I would think was built to spec.* I'm guessing a 75 kg or so.* Wonder if they would mind if I came on board with my center punch and hammer for a quick metallurgy test......
I was impressed with the thickness of the shank.* If made of the right stuff I wouldn't think you would have a problem with it.*
There were some really interesting vessels on the dock, which is good to see.* Miserable weather, but that's springtime in the NW.
Nomad Willy
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Carl,
*I would think increasing shank weight on the Rocna would INCREASE the anchors ability to set. The anchor sets laying on it's side like the Delta, Supreme and many others so a lot of chain weight right at or very close to the shank would tend to keep the shank down and the anchor on it's side where the fluke can penetrate the bottom. My understanding of these anchors is that in an upright attitude they just skid along the bottom at short scope**** ....the rode pulling the shank up off the bottom and preventing any angle of attack of the fluke to allow setting. So if one welded flat bar to each side of the Rocna's shank I'd think it would be more prone to set but would not penetrate the bottom as well with the much thicker shank. The roll bar anchors have a reputation for shallow penetration and a thickened shank would'nt help the anchors ability to penetrate.
*I would think increasing shank weight on the Rocna would INCREASE the anchors ability to set. The anchor sets laying on it's side like the Delta, Supreme and many others so a lot of chain weight right at or very close to the shank would tend to keep the shank down and the anchor on it's side where the fluke can penetrate the bottom. My understanding of these anchors is that in an upright attitude they just skid along the bottom at short scope**** ....the rode pulling the shank up off the bottom and preventing any angle of attack of the fluke to allow setting. So if one welded flat bar to each side of the Rocna's shank I'd think it would be more prone to set but would not penetrate the bottom as well with the much thicker shank. The roll bar anchors have a reputation for shallow penetration and a thickened shank would'nt help the anchors ability to penetrate.
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Delfin
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Eric, that seems to make sense, but not according to Peter Smith, the designer of the Rocna.* He says:
The Rocna is envisioned as the ultimate general purpose anchor, a large feature of which is not just performance but strength and durability.
We have not produced an alloy version primarily because we feel it would be a compromise on this. The current design would have to be modified substantially in order to facilitate alloy production, and any changes would represent a compromise. For example, an aluminium shank would not be able to possess the same tensile strength as the 800 grade steel we use without being significantly thicker, which would then affect setting performance in hard sea-beds.
What the tests show is that Rocna doesn't use 800 MPa steel, nor did they make the shank thicker to compensate for the lower grade steel they use, apparently for the weight distribution problems Smith indicated.* The Delta in the same size uses a shank width 25% greater than the Rocna to compensate for the grade of steel they use - which they say is 'manganese steel'.* I have no clue what this steel's strength is, but unlike Rocna, there don't seem to be any reports of bent Delta shanks I can find.
Nomad Willy
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Manganese steel is mostly used for it's abrasion resistance (as far as I know). We (in the mines of western Alaska) applied it to earth moving equipment like dredge buckets to keep them from wearing out as soon. One would need to do a LOT of anchoring to take advantage of that. The first time I read words from PS (that almost sounds like BS) I disliked them and nothing's changed*** ...confirming my first impression as correct. Overall I think anchor design is in line for a significant advance in performance because the best performing anchors (excluding Fortress) are roll bar anchors and I think roll bars add to holding power (as drag) but I also think they limit penetration and that is having a bigger negative effect than the drag of the bar giving a positive effect. All of those assumptions, if true, indicate a 20-25% increase in performance should be available and another "generation" of anchors should be forthcoming. If I was to apply all the knowledge and opinions I have to pick the best two anchor designs available now I'd pick #1 Fortress #2 Spade. The only way I can see to improve on the Spade's design is to overcome the necessity to lay on it's side to set like all the others of it's type. The Spade is superior to the roll bar types in that it has better penetration and is probably the most ideal shape to hold in a semi-fluid and burying deeper has less chance of breaking out. The answers are forthcoming as time will tell.
Nomad Willy
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Carl,
We have insulted, denounced and called Smith/Rocna liars and manufacturers of fraudulent products for some time now. Smith is a very competitive, verbose and defensive individual who has always been quick to defend himself and his product. We experienced Smith a while back. He picked up some eggs and tomatoes (some delivered by myself) but don't you think it's strange that the Rocna camp has been silent? As I recall they have our address.
We have insulted, denounced and called Smith/Rocna liars and manufacturers of fraudulent products for some time now. Smith is a very competitive, verbose and defensive individual who has always been quick to defend himself and his product. We experienced Smith a while back. He picked up some eggs and tomatoes (some delivered by myself) but don't you think it's strange that the Rocna camp has been silent? As I recall they have our address.
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Delfin
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*I have heard from one individual through PM who thinks it grossly unfair to test an anchor and publish the results without giving the other side the opportunity to tell "their side of the story." *As you suggest, Eric, we'd love to hear from them, but they may want to come prepared with specific empirical information that explains the results obtained in anchor tests spanning the globe. *Blaming it all on a rogue employee while touting their QC program probably isn't an adequate response, but I for one would welcome hearing from them, or Suncoast Marine who distributes their product. *I used Suncoast's web form to contact them, asking if there was a way to determine when the anchor I tested had been manufactured as well as offering the test results I obtained. *No response. *Sometimes if you have nothing to say, it is best just to keep your mouth shut. *I'm not sure there is a rebuttal for Rocna, so maybe silence is to be expected, here and on all other forums where this topic is being debated. *Rocna still has a few useful idiots defending the indefensible, so perhaps they're hoping it will all just blow over and they can get back to what they do best. *Talk a good game, deliver less.
Nomad Willy
Guru
Well......The "other side" has our address and they are free to tell their side at will. I don't think hearing from them is going to make any real difference. At least in the future those thinking the roll bar anchor best can simply buy the Manson Supreme. I did but I almost bought a Rocna. I bought the Manson because it was said to have better short scope performance in at least two anchor tests. Now I feel a bit stupid having been swayed by anchor tests because most or all of them present stuff that it would seem just can't be true. Speaking of tests there was one that tested anchor holding from the side and I don't remember any bent Rocna shanks? I have some still bookmarked so I could check.
OP
OP
Delfin
Grand Vizier
- Joined
- Jan 20, 2010
- Messages
- 3,821
Final (hopefully) update on the great Rocna saga. *
Rocna has begun the process of removing references on their web site to the high tensile steel it has told buyers its product incorporates, which has been proven to be a lie. *They are continuing to reference RINA certification, although acknowledge on a number of blogs that this isn't quite true, a.k.a. another lie. *
In private messages to owners of Rocnas they intimate that they will soon be answering all questions about why steel that measures well below their specs is really just fine. *Pretty much the only folks buying that are the useful idiots who have a Rocna on the bow, and don't want to acknowledge that a product they have raved about may well fail when subjected to a side load. *I received one such PM from someone with a Rocna breathlessly marvelling that "someone very high up in the Rocna organization" had actually called him on the phone to explain why my test results didn't mean what they mean. *Since there are only 2 people in the "Rocna organization", and it is run out of a garage office by the current owners, you don't have to reach very high to touch someone high up in the organization, but this gentleman was completely satisfied because he heard what he wanted to hear.
It looks as if the only solution Rocna has come up with is to start pretending that the lower grade steel they use compared to their specs and the less expensive and stronger alternatives like the Manson is just fine. *Whether West Marine and other retailers begin positioning Rocna for what it is - a great design, cheaply manufactured and 30% more expensive than stronger alternatives remains to be seen.
Buyer beware, I guess.
Rocna has begun the process of removing references on their web site to the high tensile steel it has told buyers its product incorporates, which has been proven to be a lie. *They are continuing to reference RINA certification, although acknowledge on a number of blogs that this isn't quite true, a.k.a. another lie. *
In private messages to owners of Rocnas they intimate that they will soon be answering all questions about why steel that measures well below their specs is really just fine. *Pretty much the only folks buying that are the useful idiots who have a Rocna on the bow, and don't want to acknowledge that a product they have raved about may well fail when subjected to a side load. *I received one such PM from someone with a Rocna breathlessly marvelling that "someone very high up in the Rocna organization" had actually called him on the phone to explain why my test results didn't mean what they mean. *Since there are only 2 people in the "Rocna organization", and it is run out of a garage office by the current owners, you don't have to reach very high to touch someone high up in the organization, but this gentleman was completely satisfied because he heard what he wanted to hear.
It looks as if the only solution Rocna has come up with is to start pretending that the lower grade steel they use compared to their specs and the less expensive and stronger alternatives like the Manson is just fine. *Whether West Marine and other retailers begin positioning Rocna for what it is - a great design, cheaply manufactured and 30% more expensive than stronger alternatives remains to be seen.
Buyer beware, I guess.
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OP
Delfin
Grand Vizier
- Joined
- Jan 20, 2010
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*Yes, and they cheerfully refunded my money, noting that the anchor was "defective" as the reason for the return. *The manager wondered if I wanted to replace it with another type of anchor, and was clearly concerned she would receive another pile of pieces for another return, but I reassured her on that point. *I'll probably pick up a Manson for my stern anchor, as it is less expensive and quite a bit stronger than the Rocna.
Sailor of Fortune
Guru
Good deal Carl- My past rants about Rocna nazis seems to come full circle. I have no working knowledge of these anchors, I have never even seen one. When any product is touted the way that the Rocna was on here, it just seemed to be unreasonable to me. Nomad willy (Eric) and others were attacked because they used "old Technology" anchoring systems, despite having worked fine for decades on their boats!
Thanks for the research and results!
Thanks for the research and results!
Nomad Willy
Guru
Actually nomadwilly attacked because of Smith's attitude and "full of himself" presentation in addition to his saying repeatedly that all other anchors were garbage. But on most bottoms the Fortress anchor still has superior performance to the "new generation" anchors and it was designed in 1939 as I recall. No anchor is without it's faults though just like there's no practical car that will do all things. The SARCA is probably the closest to a "do all things" anchor that we have*** ....well as long as we live in Australia.
bobofthenorth
Guru
- Joined
- Oct 18, 2009
- Messages
- 570
- Location
- Canada
- Vessel Name
- Gray Hawk
- Vessel Make
- Defever 43 Offshore Cruiser
I'm pretty happy with my oversized Sarca hanging on the front of Gray Hawk but I hope that if I wasn't completely happy I'd be man enough to admit it.* I certainly got plenty of advice from people with Rocna's hanging on their bows to ignore my gut feelings toward Rocna's promoters and go ahead with a Rocna purchase.* We all owe Carl a big thank you for taking the time and money to quantify the fraud they were promoting.* I'd have really loved to be a fly on the wall in that West Marine coffee room when the manager told the story of the returned Rocna.
Singleprop
Senior Member
- Joined
- Nov 10, 2007
- Messages
- 131
agree, thanks to Carl *- and to Grant King and the other that has contributed.
Even if the Rocna get their act together (not sure that they can ever recover from their F-ups) then they still need to address the fact that their manufacturer appears to produce their anchors according to the cheapest procedure (check Grants previous post where he mentions that their manufacturer uses a computer to optimize the metal versus optimizes for the strongest "grains in the steel"....not sure that it is the correct wording...... ).
I am not even sure that the other manufacturers optimizes this - maybe they can answer.......
motion30
Guru
- Joined
- Jan 14, 2010
- Messages
- 1,181
wow what great suprise another product made in china that is unsafe and not as avertised I am shocked rite next to the poison dog food and lead coated baby toys
Singleprop
Senior Member
- Joined
- Nov 10, 2007
- Messages
- 131
I found this document regarding the Rocna anchor quality:
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http://www.canmet.com/content/resources/documents/ROCNA MEMO.pdf
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http://www.canmet.com/content/resources/documents/ROCNA MEMO.pdf
Conrad
Guru
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- Oct 19, 2007
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- Canada
- Vessel Name
- Blue Sky
- Vessel Make
- Nordic Tugs 42 Hull #001
*Thanks for posting this. As a recent (Feb/11) purchaser of a Rocna anchor, I've been following these posts very closely, and am somewhat comforted by the message from Canada Metal.*
For what it's worth, the anchor performed extemely well this summer, setting very quickly and firmly in almost every instance. The one time it wouldn't set was more a function of the location so I don't hold it against the anchor.
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Delfin
Grand Vizier
- Joined
- Jan 20, 2010
- Messages
- 3,821
Yes, hopefully the new company will commit themselves to restoring the integrity of this brand. *It's a good design for many situations and it's sad that the prior management didn't match the integrity of the design with their own integrity.
However, I suspect the new owners are going to have to sweep the decks clean and get all the old guard iced if they are going to succeed in their task.
For reasons unknown to me, I recently received an unsolicited copy of an email sent from Peter Smith to a Rocna purchaser, attached below. The buyer had concerns about his anchor, and the attached is Mr. Smith's response. Not wanting to sandbag Mr. Smith, I advised him that I had been copied on this communication and asked him to respond or comment so that his perspective was taken into consideration before I posted it. Specifically, I asked 4 questions as follows, but did not receive a response:
1. You did not copy anyone from CMP on this. Are they not involved in resolving this issue with former purchasers?
2. You did copy Craig and Pocock. Does this mean they are both actively involved in dealing with this issue with you?
3. You stated that ones chain will bend before a Q620 shaft will bend. Based on your recommended chain sizes and their breaking strengths, is this a correct statement?
4. You stated that a Manson testing at 866 mpa shank strength is not as good as a defective 450 mpa Rocna. Could you give reasons why you believe this to be true?
My intent in asking the first question was to understand why the current owner of CMP would not be included in a customer service response. I frankly don't know what is going on here, and assume that CMP has delegated questions like this to Smith. However, it is puzzling that the owner of the company is having customer service handled by someone not belonging to the company.
Regarding the second question, it has frequently been stated that Craig Smith has no role at Rocna. Perhaps, but it is odd that he is copied on a customer service response. It also appears that the owner of Suncoast, the current (based on their web site) distributor of Rocna is also involved in this communication. To the extent that there are misstatements in this email, it is not unfair to say that they own them as well as Peter Smith.
The third question gets to a statement by Mr. Smith that defies physics and calls into question the degree to which he has been directly involved in some of the misstatements of fact that many have come to expect from Rocna. The breaking load of 1/4" G4 chain, recommended by Rocna on their website as appropriate for a Rocna 20, is 11,700#. The shank bending strength of the Rocna 20 anchor I tested is less than #1,550 pounds, so setting aside common sense, the statement made by Smith that the shank with*"normal usage will still not bend before your chain breaks"*is empirically false, so why would he make this statement except as a deliberate attempt to deceive the customer?
The final question goes directly to one of the aspect's of past Rocna promotion that many have found odious, and that is the tendency to puff their own product by trashing others. I understand brand loyalty, but I do not understand how a reasonable person would state that a defective Rocna with half the strength is better than a non-defective Manson at twice the strength.*
Given that these statements come from the founder of the company and the designer of the product, and given that some are false on their face, I am not sure who if anyone at Rocna can ever be trusted to be accurate in their statements to customers.
This is not to cast the slightest aspersion on CPM. They bought this brand and are trying to rebuild it. It is hard to imagine that they would repeat the mistakes of the past, but it is equally hard to understand why they would let people who do not tell the truth continue to speak for that product.
I do not own either a Rocna or a Manson, nor do I have the slightest interest in the success or failure of these companies. I do care about ethics in business, and felt that the public service element of posting this information outweighed my unease at posting a private communication, even if dis-identified.
If any of the above is unfair or inaccurate, I would welcome the correction from any source.
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However, I suspect the new owners are going to have to sweep the decks clean and get all the old guard iced if they are going to succeed in their task.
For reasons unknown to me, I recently received an unsolicited copy of an email sent from Peter Smith to a Rocna purchaser, attached below. The buyer had concerns about his anchor, and the attached is Mr. Smith's response. Not wanting to sandbag Mr. Smith, I advised him that I had been copied on this communication and asked him to respond or comment so that his perspective was taken into consideration before I posted it. Specifically, I asked 4 questions as follows, but did not receive a response:
1. You did not copy anyone from CMP on this. Are they not involved in resolving this issue with former purchasers?
2. You did copy Craig and Pocock. Does this mean they are both actively involved in dealing with this issue with you?
3. You stated that ones chain will bend before a Q620 shaft will bend. Based on your recommended chain sizes and their breaking strengths, is this a correct statement?
4. You stated that a Manson testing at 866 mpa shank strength is not as good as a defective 450 mpa Rocna. Could you give reasons why you believe this to be true?
My intent in asking the first question was to understand why the current owner of CMP would not be included in a customer service response. I frankly don't know what is going on here, and assume that CMP has delegated questions like this to Smith. However, it is puzzling that the owner of the company is having customer service handled by someone not belonging to the company.
Regarding the second question, it has frequently been stated that Craig Smith has no role at Rocna. Perhaps, but it is odd that he is copied on a customer service response. It also appears that the owner of Suncoast, the current (based on their web site) distributor of Rocna is also involved in this communication. To the extent that there are misstatements in this email, it is not unfair to say that they own them as well as Peter Smith.
The third question gets to a statement by Mr. Smith that defies physics and calls into question the degree to which he has been directly involved in some of the misstatements of fact that many have come to expect from Rocna. The breaking load of 1/4" G4 chain, recommended by Rocna on their website as appropriate for a Rocna 20, is 11,700#. The shank bending strength of the Rocna 20 anchor I tested is less than #1,550 pounds, so setting aside common sense, the statement made by Smith that the shank with*"normal usage will still not bend before your chain breaks"*is empirically false, so why would he make this statement except as a deliberate attempt to deceive the customer?
The final question goes directly to one of the aspect's of past Rocna promotion that many have found odious, and that is the tendency to puff their own product by trashing others. I understand brand loyalty, but I do not understand how a reasonable person would state that a defective Rocna with half the strength is better than a non-defective Manson at twice the strength.*
Given that these statements come from the founder of the company and the designer of the product, and given that some are false on their face, I am not sure who if anyone at Rocna can ever be trusted to be accurate in their statements to customers.
This is not to cast the slightest aspersion on CPM. They bought this brand and are trying to rebuild it. It is hard to imagine that they would repeat the mistakes of the past, but it is equally hard to understand why they would let people who do not tell the truth continue to speak for that product.
I do not own either a Rocna or a Manson, nor do I have the slightest interest in the success or failure of these companies. I do care about ethics in business, and felt that the public service element of posting this information outweighed my unease at posting a private communication, even if dis-identified.
If any of the above is unfair or inaccurate, I would welcome the correction from any source.
*
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*
Attachments
bobofthenorth
Guru
- Joined
- Oct 18, 2009
- Messages
- 570
- Location
- Canada
- Vessel Name
- Gray Hawk
- Vessel Make
- Defever 43 Offshore Cruiser
What I find entertaining is the ongoing concern about secrecy.* If I was being falsely maligned and I was defending myself to a customer I'd want him to broadcast the information from every rooftop.
