Ultraflip or Kong with chain link to anchor

[Roberto]

Have a look at these, they come in different shapes and materials, sometimes one sees them around here in anchor systems. They look flimsy but their mechanical caracteristics are outstanding. Cheap too.
I have not used them, but as you have the limited width constraint they might be an option.
CE-WLL MAILLON RAPIDE - Peguet

 

[RunAgroundHard]

… No one seems to know if this latter formula is accurate for a d shackle …

Crosby are quite clear on the de-rating of the WLL to be applied to certain styles of D and bow shackles, bolt type shackles, side loading. There is no need to calculate anything, look up their tables. The 50% WLL for a bolt type shackle is stated for 90 degree loading, includes their D shackle, bolt type.

 

[Neeves]

Crosby are quite clear on the de-rating of the WLL to be applied to certain styles of D and bow shackles, bolt type shackles, side loading. There is no need to calculate anything, look up their tables. The 50% WLL for a bolt type shackle is stated for 90 degree loading, includes their D shackle, bolt type.

I tested for the 45 and 90 degree side load on bow shackles and its 'about right'. I did not test extensively as 'about right' is good enough, or I thought so, and though shackles are cheap - costs add up. I did not test 'D' shackles as most people should be using bow shackles, excepting the accepted designs, Guardian etc, and my focus, maybe wrongly, was for the popular. I did not actually think of 'D' shackles as part of the rode

If anyone starts to become paranoid - failure of brand name shackles is rare. Reputable brand name bow shackles are an excellent investment as they last, almost, for ever.

Buy once and sleep well

 

[stranded]

Crosby are quite clear on the de-rating of the WLL to be applied to certain styles of D and bow shackles, bolt type shackles, side loading. There is no need to calculate anything, look up their tables. The 50% WLL for a bolt type shackle is stated for 90 degree loading, includes their D shackle, bolt type.

That’s really useful, thanks - I think that makes going with the Petersen 10mm 17/4 high tensile d shackle, with 6t break load at 90 degrees, a no brainer in my constrained circumstances.

 

[boomerangben]

I thought you might say that. Yet Crosby (and other makes) D shackles have the 45 degree marks and derating tables for for side loading WLL. In general terms I agree that D shackle should be used in line, but there is nothing inherently odd about using a D shackle for a load that is not in line, providing that the appropriate WLL is used.

For decades my 60lb CQR had a D shackle with a forged, peened pin through the shank, which held in lots of strong winds on a boat that veered and sheared quite bit.

Is that the CQR with a hinged shank that allows some movement to follow the shearing of the vessel . The shackle is also much bigger than hat you might use for a slotted anchor

Yes the Crosby shackles are marked as such but it is good engineering practice to reduce the SWL of a shackle for offset loading

 

[Neeves]

I thought you might say that. Yet Crosby (and other makes) D shackles have the 45 degree marks and derating tables for for side loading WLL. In general terms I agree that D shackle should be used in line, but there is nothing inherently odd about using a D shackle for a load that is not in line, providing that the appropriate WLL is used.

I have a genuine CQR, made in Scotland (it says so on the shank). Its not very big, 20lb, and it has a hole, not a slot. Maybe bigger CQRs had slots. Its around 35 years old, I bought it new. Oddly we never dragged using it, though getting into set was sometimes a bit hit and miss, mostly miss. Copies were a different story - ours would reliably drag.

The shackle for the CQR looks as if it was designed specifically for the shank. The space between the eyes of shackle and the space for the clevis look to be made for each other. The shackle is a significant piece of steel. It does increase the shank length significantly compared to current shackles.

Using the correct shackle with correct WLL is obviously sensible but knowing the WLL of the end of the shank with different shackles is a different question. If you side load a shank eye, at the end of the shank, for some anchors, you will bend the shank (as some, or a, anchor maker found out). Now - many but not all anchors are fabricated from high tensile steel - but some are probably still made from steel of a quality that does not merit mention.

It all seems an unnecessary risk, from a variety of causes, to use a 'D' shackle when there are shackles of unquestionable quality readily available. Good 'D' shackles are made by the same people who make good bow shackles - why buy a 'D' shackle - unless its the only option.

Jonathan

 

[RunAgroundHard]

… It all seems an unnecessary risk, from a variety of causes, to use a 'D' shackle when there are shackles of unquestionable quality readily available. Good 'D' shackles are made by the same people who make good bow shackles - why buy a 'D' shackle - unless its the only option.

Jonathan

… because a bow shackle can be too big for a bow roller and a D fits that can also be strong enough at 90 degree loading. It is not a risk because bow and Ds with bolt pins are designed for side loading at a reduced WLL from in line loading.

It is not hard to understand. More than one way to skin a cat. If you are not anchored to one set of beliefs you can learn from it.

 

[stranded]

… because a bow shackle can be too big for a bow roller and a D fits that can also be strong enough at 90 degree loading. It is not a risk because bow and Ds with bolt pins are designed for side loading at a reduced WLL from in line loading.

It is not hard to understand. More than one way to skin a cat. If you are not anchored to one set of beliefs you can learn from it.

 

[boomerangben]

… because a bow shackle can be too big for a bow roller and a D fits that can also be strong enough at 90 degree loading. It is not a risk because bow and Ds with bolt pins are designed for side loading at a reduced WLL from in line loading.

It is not hard to understand. More than one way to skin a cat. If you are not anchored to one set of beliefs you can learn from it.

Many ways of skinning the cat indeed. But if you are having to compromise the strength of your rode system because of the bow roller, either you are specifying too strong a rode or your bow roller is too small. Classic case of system design breaking down at interfaces. Agree about bolt shackles though

If your anchor system works for you and you sleep at night then design requirement is met. If you want to optimise the design, then there are interesting discussion points. The OP is content with his solution, you are with yours. As a professional engineer (as was) I wouldn’t be happy with a D shackle. But that is me

 

[Roberto]

Another option might be a short steel wire strop, with thimbles and all directly on the anchor and the chain; one should check the allowable bending ratio for 7x19 or 19x19 wire rope say 10/12mm, the width might possibly come below the 50mm limit?
It's actually something I would like to try with my anchor, though I have no available room between the anchor eye at rest on deck and the windlass.
Or thread some dyneema back and forth from anchor to chain to fill all available free space in the slots

 

[RunAgroundHard]

W

Many ways of skinning the cat indeed. But if you are having to compromise the strength of your rode system because of the bow roller, either you are specifying too strong a rode or your bow roller is too small. Classic case of system design breaking down at interfaces. Agree about bolt shackles though

If your anchor system works for you and you sleep at night then design requirement is met. If you want to optimise the design, then there are interesting discussion points. The OP is content with his solution, you are with yours. As a professional engineer (as was) I wouldn’t be happy with a D shackle. But that is me

If the D shackle loaded at 90 degrees is not the weakest link in the rode, why should I be worried about it? I would not commit my clients to extra costs and time because I had an opinion, as opposed to an engineered solution. If the D had insufficient strength at 90 degrees, then a different solution would be required.

As a professional engineer, you should understand this.

 

[Neeves]

W


If the D shackle loaded at 90 degrees is not the weakest link in the rode, why should I be worried about it? I would not commit my clients to extra costs and time because I had an opinion, as opposed to an engineered solution. If the D had insufficient strength at 90 degrees, then a different solution would be required.

As a professional engineer, you should understand this.

I had a quick look last night, and then lost interest as there appears to be an acceptance of a less than optimum solution. There are suppliers of chain joiners and shackles that might suit but as the OP has not defined the critical parameters - viz the width of the bow roller, the width of the anchor shank and the UTS of his chain - its all a bit of a waste of time. The absence of data suggests the OP has already decided and he too can really not be bothered - to define the issue such that we can offer a solution. My quick look identified shackles (bow) that might suit but juggling sizes Imperial and Metric, Imperial and Metric strengths became too much after a couple of glasses of wine - especially as I did not know, numerically, what were the specs of the application.

And a reason the 'D' shackle is inappropriate is that the OP is using a Bugel anchor, the manufacturer of which is unknown and the 'D' shackle will increase the lever arm effect and he may bend his anchor at the hole. I assume (though one should never assume, that anchors with a hole not a slot have a slightly shorter shank to compensate for the longer 'D' shackle). My judgement is sensitive as I have seen too many anchors, some in spiffy stainless, to ostensibly Bugel designs - that have been bent (very common the further east you go in the Med).

And extra costs and time? I had to smile - I have this uneasy thought that using a fancy stainless shackle is not the cheapest option - but then I'm a Scots skinflint and time invested in finding the best solution usually works out to be cheaper than throwing money about.


I reiterate that the issue the OP has is not isolated - there seems something fundamentally wrong with people/companies - in this case chain makers but including chandlers making and selling products for which they cannot offer compatible components. I'd level the same criticism at boat builders who sell yachts with inadequate bow rollers (or whatever). I have noticed that bow rollers have become slimmer - the OP is not alone. Finding a series of options, there is seldom a one size fits all, will be something I will continue to research at my leisure - as this thread appears to have been 'put to bed'

As mentioned 'if the OP is going to sleep well with his solution' he has solved the problem (in the end without our need to become involved)

Jonathan

 

[stranded]

Jonathan, I asked for your advice. All you do is sneer once I explain that it is not possible on my bow configuration. I have seen it from you many times before in response to many posters. You have a lot of knowledge but you wear it painfully heavily and have the suppleness of mind of a Crosby 209A bow shackle.

You really are a dick.

 

[thinwater]

Just for fun ....



I have this one.


I'm not sayin' I have the answer, I'm saying it's not quite obvious. I'm really curious why they went that way. Same on ship's anchors. And note that they are not bow shackles, which I also do not understand.

I can see why an engineer might be more comfortable with the pin through the shank. He does not have to concern himself with the possibility of weird jammed positions. He can just assign a 50% reduction in strength, install a burly shackle, and move on. But I sure don't understand why it wouldn't be a bow shackle.

The vast majority of modern yacht anchors come with slots. I think one reason may be that with the Bruce/CQR shackle system, the manufacture has to pay for the shackle. Good ones cost.

For now, I must be satisfied with not knowing.

 

[Neeves]

Jonathan, I asked for your advice. All you do is sneer once I explain that it is not possible on my bow configuration. I have seen it from you many times before in response to many posters. You have a lot of knowledge but you wear it painfully heavily and have the suppleness of mind of a Crosby 209A bow shackle.

You really are a dick.

Thank you.

You expect people to provide sensible answers to your issues - but are totally unprepared to offer them the data they need to make sensible and robust comment. Your criticise people who question you and ask for further information to allow them to comment - its not unreasonable to ask for more detail, in fact any detail. All we hear is that you bow roller is too narrow - but what is the meaning of 'too narrow'? We don't know which yacht you own, we don't have any detail of the bow roller, we don't know the UTS of your G70 chain (some G70 chain does not meet metrics G70 strengths).

I don't know your bow configuration, it is totally unknown to me.

But I was mulling over your issues.

Its seems that your own a yacht that is not fit for the purpose for which it is sold. If this is correct - I wonder what other defects might be waiting to be exposed.

The rode specified for the yacht fitted the bow roller, it does not matter which anchor nor chain - the shackle should have been sized (for strength) and should have fitted the bow roller. What has changed such that you now need a shackle that, apparently, does not exist. The shackle may not fit the bow roller because your specification for the G70 is too high - in which case you could use a smaller shackle. We don't know, all we know is that the bow roller is too narrow to meet your expectations.

You may have upgraded to G70 chain but the tension in the rode has not changed and the need for shackles capable of working with that tension has not changed. Your anchor can be the same as pre - G70, the shackles you used with the G30 chain should fit the bow roller and should be the same as needed for the G70 chain. Assuming the yacht was designed and supplied with G30 chain it needs to withstand the same tension as the G70 you bought and the shackles used with the G30 chain should be the same - whatever chain you use.

Now the G70 will be a smaller link than the G30 (but a similar strength) so the historic solution was to have an enlarged link specifically made and attached to the chain to allow use of the same shackle as was used with the replaced chain - today you could use an Omega link. But the shackle does not change, the tensions are the same.

So which shackles did you use historically, what shackles were supplied with the yacht.

And what else don't we know?

You appear to have invested G70 chain without thought for what else was needed - G70 is not cheap, a new gypsy or windlass is not cheap - and you suggest I'm a dick.

I don't sneer at your choice, I'm sorry you made that choice without the proper advice and am frustrated that you seem happy to initiate a thread but are unwilling to support the people who freely give their time to help...you.

Jonathan

To be called a dick does not upset me, its just a word.

But to be positive, as I bear no grudges - why not provide the detail and I will be more than happy to provide a answer based on your specific need

 

[stranded]

from post #5: fit through my 50mm wide stem roller and be wide enough to allow proper articulation of the 12mm chain link

From post #8: the hidden pins of the Wichards are pretty persuasive given the limitations of the 50mm anchor roller,

 

[Neeves]

There are G80 shackles that small, how about the specification on the chain, the size of anchor shank. What shackles were originally supplied - they were good enough why do you now need better

Jonathan

 

[stranded]

The setup I'll be going for will be:
* a D-shackle, probably a Petersen high tensile certified s/s with countersunk pin, or a quality normal quality one with the head cut most (not all) of the way down and slotted for a screwdriver

I knew nothing about Petersen, I do now (I've just checked the website) well sourced and well searched - another reputable source (where have they been hiding ). I like the 6:1 safety factor - so its 'better' than your (and my) chain and the 2 x WLL Proof Testing is also good (and is similar to other reputable suppliers). It has a sensible increased WLL over G3 8mm the chain (and as good as G4 x 8mm). A slotted 'rated' gal shackle (with head cut off) will work equally well

I think your arrangement will be fine - but as with all such assemblies check it regularly and discard, anything, if there are any signs of distortion.

 

[stranded]

There are G80 shackles that small, how about the specification on the chain, the size of anchor shank. What shackles were originally supplied - they were good enough why do you now need better

Jonathan

The chain is Maggi from Jimmy Green, the anchor is the original supplied by the yacht builder, when I bought the yacht at 4 years old it was attached by direct connection to Kong. I am trying to improve on that.

 

[Neeves]

Why did it take you so long to type those 2 sentences.

Thank you.

What was the chain originally supplied by the builder and/or what was the original rode as supplied by the builder - the shackle must have fitted then - unless it was originally equiped with the Kong swivel. and G70 chain (which would be unusual).

After all the negativity thrown at Maggi for galvanising chain life - your chain has lasted well.

Jonathan