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20-03-2013, 04:15
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#481
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cruiser
Join Date: Sep 2011
Posts: 267
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Re: Anchors, Bigger is Better?
Noelex wrote:
That suggests to me that if the fluke was jammed especially if caught near the tip you believe the force on the fluke/shank weld would be much higher on the Super Sarca than on the Rocna by virtue of the leverage imposed by the design.
I am sure the Super Sarca is strong enough, but I don't see how that is a positive attribute.
Rex wrote:
Well it is stipulated by the authorities of whom have made boating safer for all, I am sure all of knowledge together compared to what they have proven over many hundreds of years is something that I will not challenge, like I said before you are an armchair observer on the proof testing at least, I am sure the authorities could set you right.
Any way enough is enough, chasing my tail makes me dizzy over and out.
Regards Rex.
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20-03-2013, 04:36
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#482
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cruiser
Join Date: Nov 2007
Location: Probably in an anchorage or a boatyard..
Boat: Ebbtide 33' steel cutter
Posts: 5,030
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Re: Anchors, Bigger is Better?
Quote:
Originally Posted by congo
Noelex, I think there is somthing else thst stands out like dogs b----Iam sure you can understand this, have a look at the substancial lugs welded to the fluke, this is a reinforcement on the very pulling area, simply cannot, not possible , not allowed any welding to any part of the anchor in question when performing a proof test,
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That doesn't stand up somehow, in the rocna the load transferred to the anchor is distributed to perhaps a slightly larger area then the strop in your example. It would stop the area of the weld from deforming but have no effect on the shank connection. Your example has wooden blocks transferring load from the attachment point to the shank which most definitely would alter the behavior of the shank connection under load.
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20-03-2013, 04:46
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#483
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cruiser
Join Date: Sep 2011
Posts: 267
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Re: Anchors, Bigger is Better?
Quote:
Originally Posted by congo
Noelex, I think there is somthing else thst stands out like dogs b----Iam sure you can understand this, have a look at the substancial lugs welded to the fluke, this is a reinforcement on the very pulling area, simply cannot, not possible , not allowed any welding to any part of the anchor in question when performing a proof test,
Conchair wrote:
That doesn't stand up somehow, in the rocna the load transferred to the anchor is distributed to perhaps a slightly larger area then the strop in your example. It would stop the area of the weld from deforming but have no effect on the shank connection. Your example has wooden blocks transferring load from the attachment point to the shank which most definitely would alter the behavior of the shank connection under load.
Rex wrote: Well conchair you would have to take it up with authorities I am sure they will oblidge any queries. We dont make the regs we just obide by them, unlike some.
Noelex, one is a 55kg rocna, the Super Sarca is 185 kg, pay more attention, if it was a 55 kg Super Sarca the toe length would be almost identicle.
Regards Rex.
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20-03-2013, 04:53
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#484
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Moderator
Join Date: Jul 2007
Boat: Bestevaer.
Posts: 15,168
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Re: Anchors, Bigger is Better?
Quote:
Originally Posted by congo
Noelex, one is a 55kg rocna, the Super Sarca is 185 kg, pay more attention,
Regards Rex.
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Yes I understand that. I was referring to the relative, rather than the absolute distance. The % along the fluke if you prefer.
I have posted the photos (post 464) of both attachment points so CF members can make up their own mind if there is a significant disparity in the positioning of the load, as you claim.
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20-03-2013, 05:04
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#485
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cruiser
Join Date: Nov 2007
Location: Probably in an anchorage or a boatyard..
Boat: Ebbtide 33' steel cutter
Posts: 5,030
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Re: Anchors, Bigger is Better?
Quote:
Originally Posted by congo
Rex wrote: Well conchair you would have to take it up with authorities I am sure they will oblidge any queries. We dont make the regs we just obide by them, unlike some.
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Which authority suggested the restraining method you used as a suitable test of the shank/body junction strength? Any links?
It's obviously flawed with load being transferred through the wooden blocks to the shank. Didn't someone spot that?
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20-03-2013, 05:23
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#486
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cruiser
Join Date: Feb 2011
Location: Pittwater, Sydney
Boat: Lightwave, Catamaran, 11.5m (38')
Posts: 1,000
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Re: Anchors, Bigger is Better?
It looks to me that the wooden blocks are there to stop the strop sliding down the fluke. I'm not sure how anyone can tell, from an image, how much load the blocks take.
But if you look at the actual loads that are demanded by the CS to pass a Proof Load test they are actually not very high and they do not test the anchor at its weakest aspect. Consequently they are useful but there might be better tests - but better tests does not seem to engender much support? and certainly no interest?
From memory the IACS publish test methods - but you would need to be keen to wade through everything to find any meat.
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20-03-2013, 05:58
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#487
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cruiser
Join Date: Nov 2007
Location: Probably in an anchorage or a boatyard..
Boat: Ebbtide 33' steel cutter
Posts: 5,030
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Re: Anchors, Bigger is Better?
Quote:
Originally Posted by JonJo
It looks to me that the wooden blocks are there to stop the strop sliding down the fluke. I'm not sure how anyone can tell, from an image, how much load the blocks take.
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Exactly. I've done a fair bit of load testing and it's nigh on impossible to estimate what will happen with the friction at the point of attachment of the strop, it tends to jump as it tightens. Which ends up with a test which has an unknown amount of shear load being transferred by the blocks to the shank and not being taken by the shank weld. With unknowns in there it doesn't really tell you that much.
But on another level what happens is that if someone on the internet says an anchor load test is flawed and their own test is also flawed then somebody else stuck at home bored will mention glass houses and stones
Quote:
But if you look at the actual loads that are demanded by the CS to pass a Proof Load test they are actually not very high and they do not test the anchor at its weakest aspect. Consequently they are useful but there might be better tests - but better tests does not seem to engender much support? and certainly no interest?
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Agree, but an anchor with a load of tonnes on it makes for good PR
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20-03-2013, 06:40
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#488
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cruiser
Join Date: Sep 2011
Posts: 267
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Re: Anchors, Bigger is Better?
Well Conchair, you are obviously an expert ,the proof test loads were witnessed by Lloyds and the National Marine Safety Committee . I have spent many thousands believing that the organizations that make the rules and regulations are assuring me I have a product to be proud of, more importantly that we have met all the requirements. Iam not an expert in this field - they are.If you have a problem with what you see then I would take it up with those organizations, I'm sure they will have an answer for you. keeping in mind all of our test certs have our anchors loaded some times up to four times what is required for this proof test, further the proof testing is not carried out by me or my company, big difference as compared to the other test. But if you're going to do this then do it, don't pussyfoot around, but to be fair make sure you also present the oppositions video in question.
I would also be interested in your findings. Good to have your expertise on this forum.
Regards Rex
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20-03-2013, 07:18
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#489
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Registered User
Join Date: Jul 2006
Location: Massachusetts
Boat: Finnsailer 38
Posts: 5,823
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Re: Anchors, Bigger is Better?
Random responses and observations:
1. Yes, I love strength in my anchors, but I am uncertain (not saying right or wrong, just uncertain) that this sort of test is particularly relevant to real-world anchoring on cruising boats. I think both testing and real-world experience are important.
2. I agree that most damage I see is bent shanks, which is one reason I often use two anchors so as not to subject my well-dug in anchors to side loads. The lack of use of two-anchor sets probably provides some justification for the BIB crowd in order to provide for greater shank strength.
3. Buried two feet deep is very common here on the East Coast--if the water is clear enough I often dive down to take a look and nothing of the anchor is visible--just the chain disappearing into the mud. Frankly, I'm not convinced a big anchor would rotate at all even in a 180-degree wind shift in some thick mud bottoms, but I would rather not find out.
4. I fail to see why an anchor hooked in rock is going to see a greater load than one properly buried in the mud nearby, while the boat is under anchor. In other words, let's say it is blowing a gale and one anchor is buried and the other is hooked on just the point--won't they both be subject to the same load, which might be only a fraction of the breaking strain? Yes, upon retrieval it might theoretically be possible to subject that hooked anchor to greater strain when pulling straight up, but very few cruising boats have the windlass power to provide that level of force. Myself, if I sense a hooked anchor I resort to other methods to free it before I call in a tugboat with a hydraulic winch to pull it out.
__________________
JJKettlewell
"Go small, Go simple, Go now"
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20-03-2013, 07:49
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#490
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cruiser
Join Date: Sep 2011
Posts: 267
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Re: Anchors, Bigger is Better?
I could not agree more with what you say John, other than if the shank is wedged between two rocks and there is no movement then the stronger shank will handle more.
If the anchor is buried deep on a servier side impact it will handle more load, regardless of how deep it is buried.
Super High holding power is what you have to record to be accredited as such, if you achieve this then proof testing is the next step, it is redeemed by the authorities if the anchors designs does in fact produce this S/H/H/Power, then the proof loads have to be substantially higher, build strength is upgraded to handle these proof tests.
So whether you will ever need this extra strength who knows, but for the commercial boats they love them as they can have a 45% lighter anchor, flies in the face of bigger is better, it should also be noted some of these large commercial boats are only able to work if the anchor is doing its job, so lighter and more holding power is the key to their success, at least that is what they tell us.
Regards Rex.
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20-03-2013, 07:49
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#491
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Moderator
Join Date: Jul 2007
Boat: Bestevaer.
Posts: 15,168
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Re: Anchors, Bigger is Better?
Quote:
Originally Posted by Kettlewell
Random responses and observations:
1. Yes, I love strength in my anchors, but I am uncertain (not saying right or wrong, just uncertain) that this sort of test is particularly relevant to real-world anchoring on cruising boats. I think both testing and real-world experience are important.
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Unfortunatly I don't think the proof loading test does have much relevance. They don't require any sideways pull. Considering they are testing the shank in its strongest direction the requirements don't seem vey onerous.
The uniform shipping laws that I understand oversea the the proof load test are the same people that suggest that 3m (9feet) of chain is acceptable for a sea going vessel with an anchor under 25Kg (55lb) above that size they require a whopping 6m (18feet) of chain.
I don't think they set the bar very high.
Many vessel particuarly in Australia require a proof loaded anchor and having gone to the considerable expense testing it is understandable that manufactures want to publicise the certification.
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20-03-2013, 08:18
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#492
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cruiser
Join Date: Nov 2007
Location: Probably in an anchorage or a boatyard..
Boat: Ebbtide 33' steel cutter
Posts: 5,030
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Re: Anchors, Bigger is Better?
Quote:
Originally Posted by congo
Well Conchair, you are obviously an expert ,the proof test loads were witnessed by Lloyds and the National Marine Safety Committee . I have spent many thousands believing that the organizations that make the rules and regulations are assuring me I have a product to be proud of, more importantly that we have met all the requirements. Iam not an expert in this field - they are.If you have a problem with what you see then I would take it up with those organizations, I'm sure they will have an answer for you. keeping in mind all of our test certs have our anchors loaded some times up to four times what is required for this proof test, further the proof testing is not carried out by me or my company, big difference as compared to the other test. But if you're going to do this then do it, don't pussyfoot around, but to be fair make sure you also present the oppositions video in question.
I would also be interested in your findings. Good to have your expertise on this forum.
Regards Rex
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First off the strength or quality of your product has never been mention, that isn't really in question, there's nothing to suggest your product isn't top notch.
You had a go at the other test, "My test is better than their test". Can you explain why that is? The force ends up on roughly the same surface area. If you're going to have a go at others then back it up.
It may well be that welded lugs make a substantial difference, I can't see how other than stiffing up the localized area of the fluke.
Perhaps you could explain better how that would have any effect on the join between the shank & anchor body.
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20-03-2013, 08:45
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#493
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cruiser
Join Date: Sep 2011
Posts: 267
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Re: Anchors, Bigger is Better?
Conchair wrote:
First off the strength or quality of your product has never been mention, that isn't really in question, there's nothing to suggest your product isn't top notch.
You had a go at the other test, "My test is better than their test". Can you explain why that is? The force ends up on roughly the same surface area. If you're going to have a go at others then back it up.
It may well be that welded lugs make a substantial difference, I can't see how other than stiffing up the localized area of the fluke.
Perhaps you could explain better how that would have any effect on the join between the shank & anchor body
Rex wrote:
Read my previous post’s, it is more than explained and backed up “My test is better than their test" what rubbish, it is not my test, I thought you were some sought of an expert on this proof load testing, you are simply drawing straws my friend , if you cannot understand the difference then you will just have to join Noelexs jury and vote, I already know the verdict as the jury appeared minutes after Noelex presented my none evidence. You have the answers then follow up your suspicions, I say suspicions as I know longer have faith in your expertise, I am disappointed as I thought you would follow through.
By the the way Noelex, they are not my claims, it is simply proof test procedure.
Gee the bait I put on that mouse trap has rained in a whole field.
Never mind it is all bit of fun except for the vid proof test.
Regards Rex.
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20-03-2013, 09:35
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#494
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cruiser
Join Date: Sep 2011
Posts: 267
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Re: Anchors, Bigger is Better?
The fact remains Conachair, the vid clearly states that the procedure they are demonstrating are that of which is in lewd with various classification societies, this is not so, ask these classification what is wrong with the way they are testing if you are so interested and want answers.
Oh never mind, I think I am beginning to understand, if someone in my family did wrong I would support them at all cost and defend whatever was said against them regardless.
IT’S BEEN FUN GOOD NIGHT AND GOOD BYE.
Regards Rex.
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22-03-2013, 00:28
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#495
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cruiser
Join Date: Feb 2011
Location: Pittwater, Sydney
Boat: Lightwave, Catamaran, 11.5m (38')
Posts: 1,000
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Re: Anchors, Bigger is Better?
I hope this link works,
Storm Hits Granny Smith in Trousers Bay, Furneaux Islands
It appears I'm not the only one with a wimpy anchor.
But I'm simply the messenger for Granny Smith who are a bit preoccupied.
And for Americans, Granny Smith is an apple and Tasmania sometimes known as 'The Apple Isle' (because they grow a lot of apples)
In case anyone asks: no-one seems to have any idea why its called Trousers Bay. I've never stopped there but the notes I have suggest there is weed on sand.
Jonathan
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