I hate to do this...but

I saw this and thought of you.....

IMG_0920.jpg


While we're on the subject of bent anchors, a 10kg Stainless anchor.

Sorry to say I have no more details...I saw this in an office and grabbed a quick pic.
 
snooks said:
I saw this and thought of you.....

IMG_0920.jpg


While we're on the subject of bent anchors, a 10kg Stainless anchor.

Sorry to say I have no more details...I saw this in an office and grabbed a quick pic.
Click to expand...

Running the risk of setting it all off again, I was pointing this potential problem out several hundred posts ago. I was shouted down by posters who seemed unable to understand the point I was making.

It's all very well designing an anchor with a shank strength of, for example, 800 MPa. If the same design is then made in aluminium, or any stainless steel including heat treatable duplex, it will have about half the bending resistance of the original. Unless the shank is made to a very different design that significantly increases its cross sectional area it would be advisable to steer clear.
 
vyv_cox said:
Running the risk of setting it all off again, I was pointing this potential problem out several hundred posts ago. I was shouted down by posters who seemed unable to understand the point I was making.

It's all very well designing an anchor with a shank strength of, for example, 800 MPa. If the same design is then made in aluminium, or any stainless steel including heat treatable duplex, it will have about half the bending resistance of the original. Unless the shank is made to a very different design that significantly increases its cross sectional area it would be advisable to steer clear.
Click to expand...

Yes, this is quite obvious. If you have a shank made of 800 MPa steel and then you make one out of a lower strength metal with the EXACT same dimensions, and use the EXACT same machining steps, of course that shank is going to be weaker and more prone to bending.
 
Nostrodamus said:
Well it’s a done deal. I have ordered a Manson Supreme.
What was interesting was that my chandler’s supplier/ importer could not supply one as the pallet they had had problems with the galvanising which was not up to standard. Hence they would not sell any.
This strangely enough gave me more confidence in the product as they will only supply a product that is “fit for purpose”.
Every manufacturer from time to time has problems with quality control but the difference is that some hold their hands up, say it is not good enough and refuse to sell them to the public before it becomes an issue.
Click to expand...

THAT speaks volumes!

I wrote WM 5 days ago on the issue of Rocna discrepancies of specs to tests, and have no reply yet.

If and when I do, that will also speak volumes. I know which anchor I won't buy, I am just not sure yet which chandler I won't use.
 
Re: Rocna Size
I received this PM from an individual who owns a Rocna and felt I was being unfair in testing an anchor and publishing the data. This individual had been badgering me to send the information to Holdfast so they could respond, which I didn't think necessary. I figured they would respond when they had something to say and was certainly aware of the controversy.

"Since you seemed unwilling to do it I sent the link to the Rocna discussion to Rocna yesterday morning. Yesterday afternoon at work I was fairly amazed to recieve a phone call from a very highly placed person in the Rocna organization. He told me they were well aware of your and other's allegations about their product as other customers have sent themt the links or the posts to them as well.

He told me that while the test data you recieved from the metallurgy outfit you had test your anchor is not flawed your interpretation of that data is. I agreed not to convey any of the details of the expoanation I was given as the Rocna orgnanization is currently determining how, when and if to respond to the allegations against their product. If they do so it will most likely be as a press release, not as individual postings to amateur boating forums on the internet, although you never know.

After hearing the explanation of the situation from the Rocna representative I have no doubt that their anchors are made from exactly what they say they are made of. And the reason your test came out the way it did is very clear, even to a layman like me. If and when they issue a statement it will become clear to you, too, I expect.

Needless to say I was extremely impressed with Rocna's response to me. I would never have guessed a person at that level in the organization would make an individual, personal response like that, although he said that he did so because it's imporant to hiim that Rocna customers know the truth about the anchor they have purchased.

This is all I will say on this subject. You will have to wait for Rocna's official statement to learn why your interpretation of what is correct data is flawed."

This is interesting. Perhaps we will hear from Rocna soon, and find out why the data presented in my test is correct, including presumably the lab's statement that the anchor didn't meet the ASTM 0514 steel grade, but my conclusion that 626 MPa is not the same as the steel they promise on their website, or equal to the 810 MPa steel used in the Manson is incorrect. I can't wait....
__________________
 
Delfin said:
He told me that while the test data you recieved from the metallurgy outfit you had test your anchor is not flawed your interpretation of that data is.
__________________
Click to expand...

My limited knowledge of metallurgy would suggest that a product constructed of high tensile 800 MPa steel would measure lower following the heating necessary to weld and galvanise the anchor.
I wonder if this is what Rocna are referring too?
 
noelex said:
My limited knowledge of metallurgy would suggest that a product constructed of high tensile 800 MPa steel would measure lower following the heating necessary to weld and galvanise the anchor.
I wonder if this is what Rocna are referring too?
Click to expand...

Our Anchors Are Made Of Hematite, Coke and Limestone!

Note: some processing is involved
 
Delfin said:
This is interesting. Perhaps we will hear from Rocna soon, and find out why the data presented in my test is correct, including presumably the lab's statement that the anchor didn't meet the ASTM 0514 steel grade, but my conclusion that 626 MPa is not the same as the steel they promise on their website, or equal to the 810 MPa steel used in the Manson is incorrect. I can't wait....
Click to expand...

For a fair comparison it would be nice if someone could buy, slice and test a Manson to see how welding, galvanizing and other manufacturing processes affect the steel in that.
 
noelex said:
My limited knowledge of metallurgy would suggest that a product constructed of high tensile 800 MPa steel would measure lower following the heating necessary to weld and galvanise the anchor.
I wonder if this is what Rocna are referring too?
Click to expand...
Could be, but wouldn't the Manson also be so affected? It appeared not to be in the test done on that anchor.

I did check the Bisalloy site and found the following in the technical guide for galvanizing Bisalloy"

"Galvanising does not affect the mechanical properties of BISPLATE® structural grades.
However, there are some precautions & recommendations that should be taken into
account when galvanising BISPLATE®."

Bisalloy 80 is structural grade Bisplate and matches the kind of steel Rocna says they are using, so I think they are going to have to come up with another explanation.
 
Last edited:
Delfin said:
Could be, but wouldn't the Manson also be so affected? It appeared not to be in the test done on that anchor.

I did check the Bisalloy site and found the following in the technical guide for galvanizing Bisalloy"

"Galvanising does not affect the mechanical properties of BISPLATE® structural grades.
However, there are some precautions & recommendations that should be taken into
account when galvanising BISPLATE®."

Bisalloy 80 is structural grade Bisplate and matches the kind of steel Rocna says they are using, so I think they are going to have to come up with another explanation.
Click to expand...

If you recall, I suggested you get your lab to do a hardness traverse across a section including the weld to determine how far the HAZ extended. I don't think you did this but I would be very surprised if any reduction of properties extended more than a few millimetres into the stock, a region that clearly could not be included in the mechanical testing that was carried out. I cannot see anything in the test procedure that can be criticised, nor, if it comes to that, in your interpretation of the results.

Galvanising temperature is typically 460C. The Bisalloy literature quotes stress relieving temperatures of 540 - 570C, above which its mechanical properties may be affected. I conclude from this information that galvanising should be perfectly safe if done correctly.
 
Once again Racno are telling people that something is coming soon.

This time, they are going to have a full explanation in the near future.
A few weeks ago they were going to have tests conducted and would post the information.
Then it was an explanation of other people test results.
Then it was the RINA test certificates.

Tomorrow never comes in Racno-land.
 
GrantKing said:
I have a spare flak jacket to match mine...I will send it to Delphin;)
Click to expand...
Heck, I live in red neck country so they better bring reinforcements. A few Christmases ago, my two oldest sons bought each other SKS Chinese assault rifles with the optional banana clips. Now that really caught the spirit of the season! :eek:

And here's a pic of my granddaughter getting ready for the prom...
 
Last edited:
Ubergeekian said:
For a fair comparison it would be nice if someone could buy, slice and test a Manson to see how welding, galvanizing and other manufacturing processes affect the steel in that.
Click to expand...

Racno could do it, but we know they won't.
They could have done it long ago to support their numerous claims about inferior prodcuts. :p:p
 
You must log in or register to reply here.

Share this page

Top