I hate to do this...but

Twister_Ken said:
Blimey,

So you can build a pyramid of 800,000 small apples on a square metre of the stuff before it bends.

Love to see the test rig!
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No, 800,000,000!

When you consider that Grade 30 chain, by my estimate, has an ultimate strength of about 26 ton/in.sq, well under 400 MPa, against the yield strengths being quoted, you may appreciate my cynicism when it comes to anchor manufacturers bickering amongst themselves about the strengths of their products.
 
vyv_cox said:
800 MPa is 58 ton/in sq, a good quality engineering steel figure, the sort of stuff that critical engine parts like conrods and valves might be made from. The problem for anchors is that such steels need a fair amount of carbon in them but they cannot be welded easily and, as I understand it, are not allowed by whatever authority is responsible for anchor manufacture. Hence the Bisalloys and similar materials that have low carbon but quite high strength derived from bismuth. These seem to be made mostly in Australia and not many other places.
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The steel that Rocna states they use and must be used given the thickness of their shanks is 800 MPa ultimate tensile strength (the force required to break a standard piece of material), which Bisalloy 80 is. The more important measurement is yield tensile strength, which is the force beyond which a standard piece of the material will no longer 'spring back' to its original shape. Bisalloy 80 has a yield tensile strength of 750 MPa. Manson and Sarca use Bisalloy 80, although Manson also uses an equivalent steel from Japan, and other similar types are commonly available worldwide. Bisalloy is an Aussie brand name. Don't ask me why, but Bisalloy has no bismuth in its component list, so its characteristics do not derive from that element.
 
vyv_cox said:
No, 800,000,000!

When you consider that Grade 30 chain, by my estimate, has an ultimate strength of about 26 ton/in.sq, well under 400 MPa, against the yield strengths being quoted, you may appreciate my cynicism when it comes to anchor manufacturers bickering amongst themselves about the strengths of their products.
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I'm not sure the owner of the anchor bent 90 degrees in Venice Lagoon would agree. His anchor seemed to have failed pretty decisively, although I don't recall hearing that his anchor chain gave way first.
 
SolentBoy said:
I dont know.

Just because a test on one anchor says it is right or not right, does not neccessarily mean your own anchor is the same, unless we can make the assumption that all items within the same batch are the same hardness.

The issue will therefore be what batch the anchors being tested are from.

Who is doing a testing anyway? Anyone know where the anchors are that are being tested, and from what time origin?
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The anchor I am having tested was purchased last week from current stock at a local West Marine store. The results should be available next week.

If the metallurgy for an anchor purchased in Washington State is the same as that purchased and tested by Manson in NZ and the same as that metallurgy Grant King, former production manager for Rocna says has been used since production was moved to China, it seems reasonable that one could conclude that all anchors made by Rocna with the imprint casting on the flukes is made of a lower grade steel than advertised and that customers paid for.

For some, paying more for one level of quality and strength but receiving lower quality and strength is a non-issue. We have heard that perspective from a few on this thread. For the rest of us who don't appreciate being lied to and taken for fools, not paying more for less makes sense. To each his own, I guess.

To those who have already purchased a Chinese Rocna assuming it met stated Rocna standards for manufacturing, it will no doubt perform fine as long as it is not subjected to the side loading it was designed for, but not manufactured to withstand.
 
Fascinating thing, the internet...

A minute ago, I couldn't find this thread on the forum's contents page. No idea why. So instead, I googled: "Sorry to do this, but...mpa". Guess what? Straight back here. Amazing. Perhaps it shows how obscure our subject is?!
 
As a very interested party in this thread and when clearing off some backdated calender dates in the office, I see some of the quotations / epigrams which may have some relevance to things here........... :)

"Well timed silence has more eloquence than speech".

"Nobody stands taller than those willing to stand corrected".

"An apology is the superglue of life, it can repair just about anything".

"Your most unhappy customers are the greatest source of learning".

"Real Knowledge is to know the extent of one's ignorance".

"When you get to the end of a rope, tie a knot and hang on". ( I like the soud of that!)

I wonder which ones you think most relevent and to which posting on this thread?

S.:)
 
Scotty Twister, those are the kinds of wisdom that make the self-respecting hearer want to allocate swift kickings in the speakers' direction!

I don't deny their truth, I just despise their conceited succinctness. :mad::D
 
dancrane said:
Fascinating thing, the internet...

A minute ago, I couldn't find this thread on the forum's contents page. No idea why. So instead, I googled: "Sorry to do this, but...mpa". Guess what? Straight back here. Amazing. Perhaps it shows how obscure our subject is?!
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Obscure? Dunno. The previous thread had about 750 contributions before R got all personal and engineered for it to be pulled. 'Son-of' here now has 560 contribs, so a grand total of over 1300 two-cents-worth so far, and climbing.

Doesn't seem obscure to me. Or maybe it just allegedly reflects the alleged popularity of allegedly unmasking alleged cheats.

Not that I make any such allegations, m'lud. I leave that to the other allegators.
 
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Actually I was only thinking it's impressive that the search engines pick up a very ordinary phrase, plus an odd abbreviation, and find this site, without any others even being suggested!

Though, I am surprised at this forum's appetite for metallurgy and legal/less-than-legal sales/representation of products.

By the way, what was the even more drawn-out previous thread? I'm not stirring, honestly. Who is "R"? What did he get upset about?


God, I really need to be back at work. ;)
 
dancrane said:
Scotty Twister, those are the kinds of wisdom that make the self-respecting hearer want to allocate swift kickings in the speakers' direction!

I don't deny their truth, I just despise their conceited succinctness. :mad::D
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They do say the truth hurts! Kick away... but not in my direction!

"conceited succinctness". .. are you one of those Telegraph crossworders, is it an anagram for something to do with anchoring?

S :)
 
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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.
 
Rigger M, that's very good work! But, I'm mainly full of self-congratulation, for having got you gentlemen off the subject of anchors, for a while...

Honestly, wasn't this last page more entertaining than the previous fifty-something pages?

(don't kid yourselves I care if it wasn't)
 
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