Uncooperative Anchor...
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mjcoon
Well-Known Member
I don't understand the bit about "take the whole chain out" unless you mean merely disengaging from the gypsy (which only involves a metre of chain at the most).
And pivoting with the tide can only have an effect if there is a swivel. Otherwise any twists will spin out as the anchor lifts, else there will be knots in the chain or it comes off the gypsy!
Mike.
john_morris_uk
Well-Known Member
The words "Kong Italy" in the photograph maybe a clue
That seems to be a fair point however I must be going senile as I don't remember that logo design on our Kong Swivel either. I looked at it in the photo and didn't recognise the logo and assumed it must be another make.
Assuming they've changed their logo and it is a Kong product, their problem might easily be that they have attached it straight to the anchor. When you attach it in this way, the swivel can get trapped and twisted in ways that it isn't designed for - as per the illustration. When it twists up on the shank and the anchor is wedged firm it produces a very strong shearing action on the swivel. Many people say that you need a few links of chain between the anchor and the swivel to stop this happening.
Presumably their comment about paying multiples of the cost of a Kong is an error.
Ex-SolentBoy
Well-Known Member
What I meant is that even if you take the whole chain out and lay it on a pontoon and make sure it is not twisted in any way when you put it back, you can still get twists when you use it again. Lifting off the gypsy was not an option for me. That would be the obvious thing to do, but with a very heavy anchor it is not an easy option.
The chain can get twisted without a swivel if it gets flipped on the bottom, or during the process of laying and resetting.
You may think the going astern technique wont work, and I will not get into an argument about the mechanics with you. I can only say that it really does work and I know several other owners who swear by it (I didn't invent the process).
Try it before you dismiss it. Its so simple. clearly the chain was aligned properly when the anchor went down, and the water flow simply turns it back the way it was.
Delfin
Well-Known Member
The article posted clearly identifies the swivel as a Kong (note the caption to the picture), and they don't say they paid "multiples of the cost of a Kong". But then again, John, you are entitled to believe whatever you like, regardless of the facts.
Because the Kong is a clamshell, it is dependent on the strength of what holds the two parts together. As shown in the article, this system can and has failed. The Ultra swivel is a different design, not subject to this issue. The point of the Ultra recommendation is to solve the issue of rotating the anchor. On some boats it's no big deal to rotate it by hand to bring it on board. On others, high bulwarks, the weight of the anchor or a desire not to visit the chiropractor may argue for a way to avoid that problem. The Ultra is one solution that rates a lot stronger than the chain, so it is hardly the weak link if added to a system.
p.s. I believe you'll find the Ultra is no more expensive than the Kong, but is 3 times stronger and, in addition quite simply solves the problem described by the OP.
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john_morris_uk
Well-Known Member
The article posted clearly identifies the swivel as a Kong (note the caption to the picture), and they don't say they paid "multiples of the cost of a Kong". But then again, John, you are entitled to believe whatever you like, regardless of the facts.
No need to be rude - I was only explaining why I had got confused.
My reference to their purchasing as multiples of the cost of a Kong came from this line in their article.
It refers to them buying from 'a manufacturer' as against Kong which I took to be 'not Kong' and as I didn't recognise the logo... hence my confusion. However if they have managed to break one then that is news. The Kong was the only swivel that passed some independent tests on swivels performed by Vyv and which were published in Yachting Monthly or PBO a couple of years ago.
If you have any evidence (apart from the manufacturers claims) that the Ultra is as strong as you say it is, then I will put one on my shopping list. I would prefer to wait for some independent testing though.
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Delfin
Well-Known Member
You mean, you're not entitled to believe whatever you like?
Regardless, the quote you provide is from the author of the article, not the people reporting the broken Kong swivel. I gather he is talking about the Ultra since at the end of his article he names that device. However, the price for a Kong swivel for my 12.5mm chain is over $800 from Jamestown Disributors while the Ultra cost around $400. I guess shopping around makes sense.
Regarding testing, when a manufacturer stamps the breaking strength on the product one can usually assume it isn't based on fantasy. If the Ultra is half as strong as the manufacturer states it is still stronger than the Kong by quite a bit. Since the weakest link on the Ultra is the solid, unscrewed pin that attaches the chain (on mine 14.5mm) one can simply look up the sheer strength of that stock in 316L over a span of 15mm and do a bit of your own 'independent testing' if you like. Or you can wait for Mr. Cox to do it for you.
john_morris_uk
Well-Known Member
A Kong Swivel is between (approximately) £40 and £60 depending on where you get it from in UK
I would like to sell a few at $800; I could buy a new boat!
Delfin
Well-Known Member
Yep, pricey little buggers. If you are unfortunate enough to have 12.5 mm chain, you have to go to what they make for 5/8" chain, and then have a much weaker component than alternatives.
But if you only have 5/16" chain (the $60 model), what the heck does one need a swivel for in the first place?
john_morris_uk
Well-Known Member
Even in the larger size they are less than half that price here:
http://www.marinesuppliesdirect.co....g-anchor-connector-swivel-stainless-878-p.asp
£234 = $366 according to my calculations
PS we have 10 mm chain which is a fraction more than 3/8" and today I have learned that Kong swivels are made in larger sizes.
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vyv_cox
Well-Known Member
T
Not quite sure these quotes are comparing like with like. The SWL for the Kong is based on the bending load assuming a 90 degree pull. The Ultra seems to be an axial pull. Based on my testing of the Kong I would estimate its axial SWL to be far higher.
The test certificates for the Ultra don't state exactly what was done but based on the huge number of samples I guess that the majority were proof tests. Quite impressive though. I have never been totally impressed with the ball joint idea, it gives limited angular pull capability but nowhere near as much as two links of chain does. On the same theme, I see the pic of the Kong advertisement suggests using a bow shackle to prevent force acting laterally to the jaws. When I tried this I found that the jaws often wedged against the anchor by the action of the shackle, even though I tried several different shackle sizes.
Not quite sure these quotes are comparing like with like. The SWL for the Kong is based on the bending load assuming a 90 degree pull. The Ultra seems to be an axial pull. Based on my testing of the Kong I would estimate its axial SWL to be far higher.
The test certificates for the Ultra don't state exactly what was done but based on the huge number of samples I guess that the majority were proof tests. Quite impressive though. I have never been totally impressed with the ball joint idea, it gives limited angular pull capability but nowhere near as much as two links of chain does. On the same theme, I see the pic of the Kong advertisement suggests using a bow shackle to prevent force acting laterally to the jaws. When I tried this I found that the jaws often wedged against the anchor by the action of the shackle, even though I tried several different shackle sizes.
Delfin
Well-Known Member
Unless one is on a permanent mooring or spending weeks at anchor I've never been quite sure what use a swivel is under most circumstances. The Ultra, however, improves on the Wasi design by the addition of a tab that forces the anchor off balance if it comes up bass ackwards resulting in it righting itself. That is the reason we have one, since our bulwarks are high enough and the anchor heavy enough that slinging the hook around by hand required feats of strength and agility. The only point the swivel has in my view is to allow the anchor to rotate on retrieval.
Mr. Cox, does the shorter lever arm of the Wasi or Ultra reduce the load on the jaws of the swivel where they attach to the anchor when side loaded? I can't visualize it being so, but I'm not sure. If not, then like you, I can't see the point of the ball either.
Incidentally, I asked Quickline if the breaking strength of their swivel was lateral or in line and they said lateral. Perhaps so.
vyv_cox
Well-Known Member
I have owned two Maxwell windlasses, in each case the manual recommends that a swivel be used. I note, and have recently videoed, that when recovering the chain it twists considerably, before the anchor is off the bottom. I'm not sure whether this is a function of the windlass itself or some characteristic of the chain but a swivel seems a good idea to take out this twisting.
I would think that a shorter swivel, or connector, would reduce lateral loading of the jaws as a function of shorter lever arm, assuming a constant pull on the chain. The ball joint would therefore reduce the lever length further, so could have benefits. As said though, a couple of links of chain overcomes the problem completely but of course, as you say, makes turning the anchor more problematic. With my 15 kg Rocna it isn't a problem at all, I rotate it by hand.
I would think that a shorter swivel, or connector, would reduce lateral loading of the jaws as a function of shorter lever arm, assuming a constant pull on the chain. The ball joint would therefore reduce the lever length further, so could have benefits. As said though, a couple of links of chain overcomes the problem completely but of course, as you say, makes turning the anchor more problematic. With my 15 kg Rocna it isn't a problem at all, I rotate it by hand.
Delfin
Well-Known Member
Thanks for the informed insights.
Prior to my putting a swivel on, I tried to deal with backwards presentation of the anchor on retrieval by physically rotating the chain on the windlass. This would solve the problem for a couple of cycles, then the same problem would occur. I think it had to do with the balance of the Claw. I first got a Suncor swivel which is beefy enough but I was concerned about the fact that the retaining pin was screwed into the body of the swivel - a concern you have validated with your testing, and the anchor still came up backwards regularly. Now the Suncor has been replaced with an Ultra that solves that problem. So like you, I have no clue what causes the twisting but it happens, and it doesn't seem to unwind with a swivel, hence my wondering what they were good for without the Ultra feature that flips the anchor into the correct position.
Prior to my putting a swivel on, I tried to deal with backwards presentation of the anchor on retrieval by physically rotating the chain on the windlass. This would solve the problem for a couple of cycles, then the same problem would occur. I think it had to do with the balance of the Claw. I first got a Suncor swivel which is beefy enough but I was concerned about the fact that the retaining pin was screwed into the body of the swivel - a concern you have validated with your testing, and the anchor still came up backwards regularly. Now the Suncor has been replaced with an Ultra that solves that problem. So like you, I have no clue what causes the twisting but it happens, and it doesn't seem to unwind with a swivel, hence my wondering what they were good for without the Ultra feature that flips the anchor into the correct position.
