Ultraflip or Kong with chain link to anchor

[vyv_cox]

Is it feasible to do the same with chain of higher grades?

I cannot see a reason why not. All three marine grades, G30, 40 and 70, have low levels of carbon. G40 has a little more than the almost dead mild of G30, plus a little more manganese. The reality is that it is cheaper to produce to G40 even though it may be sold as G30. G70 is a heat treated version of G40.

All of these are ductile and can be deformed without risk of fracture or developing cracks.

 

[Neeves]

Yes but… they won’t fit through my anchor roller, hence my proposed compromise.

If I use your recommended Crosby or similar, I will be safe because I won’t be able to launch the anchor so will be in a marina. The best solution for me is one that will work on my boat. I would like to be able to anchor when conditions are kind, so would value your view specifically on the solution I have proposed - in particular does a 6:1 safety factor on a 2t wll shackle mean a nominal 12t break load?

Simply repeating what you know about other solutions that can’t work for me is of purely academic interest in the context of this thread, though I hope may be of use to others.

A 3/8th" Crosby G209a shackle has a WLL of 2t and the clevis pin fits in 8mm metric chain. If you have some unconventional 8mm chain than add a G100 8mm Omega link as an elarged link and the 3/8th shackle will definitely fit. We had a high tensile 6mm chain with a 6mm G100 Image link and a 3/8th" shackle. Grade B shackles are individually proof tested to 2 x WLL, that's 4t (that's part of the Grade B test protocol).

Shackles are tested and rated in a straight line pull so a 6:1 safety of a shackle with a WLL of 2t demands that when tested in a straight line pull then the min break load is 12t. The shackle maker will define (or not) what happens in the application where the tension is off centre. The Grade B test protocol also demands that under proof test the shackle has not deformed such that it cannot be opened - your 12t UTS is not much use if it deforms easily. If you read the small print of Crosby, Peerless etc - they all make the point of the degradation to strength that occurs when their shackles are not centrally loaded. If the off centre tensile strength of the shackle is not mentioned, in the small print (and often its well hidden away or not mentioned) then contact the manufacturer and also ask at what tension, straight line pull, does the shackle deform such that it cannot be opened.

Look at this link and check if any of these shackles fit you bow roller.

Peerless | Peer-Lift® Screw Pin Anchor Shackles

Yoke also make a 5/16", so slightly smaller than a 3/8th" shackle with a high WLL

You have not declared who makes your G70 chain and what is its specification. I query the specification as some G70 chain is available - but not actually made to a G70 specification (its a fudge). We have not seen an image of your bow roller nor know its dimensions - we cannot make recommendations without all the background.

You say

Simply repeating what you know about other solutions that can’t work for me is of purely academic interest in the context of this thread, though I hope may be of use to others.

maybe you can help your self by being less critical of people trying to help and give them the tools they need to answer YOUR problems

Jonathan

 

[vyv_cox]

Wichard say their 17/4 shackles are not to be used for mooring purposes. Given that Vyv has successfully used one of those for years, I assume this means not for permanent immersion and that anchoring should be fine?

The Petersen pins do not appear to be self locking like the (weaker) Wichards - do I use permanent or medium loctite?

I assume as you do, that when they say mooring they don't mean anchoring. Interesting that they do not say the same for their 316 shackles. I suggest that any stainless steel used in a permanent mooring is risky

I have always used Loctite 242 after testing it. This is the medium grade. Not only on the Wichard but also on the Kong connecting screw.

 

[Neeves]

Two simple questions, as well as the specification of you chain.

What is the width of your bow roller?

What is the thickness of your shank?

Jonathan

For Loctite

Adhesives Test - Practical Sailor

 

[stranded]

A 3/8th" Crosby G209a shackle has a WLL of 2t and the clevis pin fits in 8mm metric chain. If you have some unconventional 8mm chain than add a G100 8mm Omega link as an elarged link and the 3/8th shackle will definitely fit. We had a high tensile 6mm chain with a 6mm G100 Image link and a 3/8th" shackle. Grade B shackles are individually proof tested to 2 x WLL, that's 4t (that's part of the Grade B test protocol).

Shackles are tested and rated in a straight line pull so a 6:1 safety of a shackle with a WLL of 2t demands that when tested in a straight line pull then the min break load is 12t. The shackle maker will define (or not) what happens in the application where the tension is off centre. The Grade B test protocol also demands that under proof test the shackle has not deformed such that it cannot be opened - your 12t UTS is not much use if it deforms easily. If you read the small print of Crosby, Peerless etc - they all make the point of the degradation to strength that occurs when their shackles are not centrally loaded. If the off centre tensile strength of the shackle is not mentioned, in the small print (and often its well hidden away or not mentioned) then contact the manufacturer and also ask at what tension, straight line pull, does the shackle deform such that it cannot be opened.

Look at this link and check if any of these shackles fit you bow roller.

Peerless | Peer-Lift® Screw Pin Anchor Shackles

Yoke also make a 5/16", so slightly smaller than a 3/8th" shackle with a high WLL

You have not declared who makes your G70 chain and what is its specification. I query the specification as some G70 chain is available - but not actually made to a G70 specification (its a fudge). We have not seen an image of your bow roller nor know its dimensions - we cannot make recommendations without all the background.

You say

Simply repeating what you know about other solutions that can’t work for me is of purely academic interest in the context of this thread, though I hope may be of use to others.

maybe you can help your self by being less critical of people trying to help and give them the tools they need to answer YOUR problems

Jonathan

I am sorry Jonathan, I didn’t mean to be rude - I value your knowledge which is why I seek it. In this case, since you clearly don’t want to engage with any possible solution which is not your solution, I will make the best choice I can with the information I have.

 

[stranded]

I assume as you do, that when they say mooring they don't mean anchoring. Interesting that they do not say the same for their 316 shackles. I suggest that any stainless steel used in a permanent mooring is risky

I have always used Loctite 242 after testing it. This is the medium grade. Not only on the Wichard but also on the Kong connecting screw.

Thanks Vyv. Think this is what I will go with then.

 

[boomerangben]

Still wrestling with this I came across a thread from a few years ago which seems to be the best solution for my situation and just wanted to check I am not missing something crucial.

Peterson 10mm 17/4 high tensile stainless shackles with flush Allen key pins. D shackle pin through anchor shaft hole, crown to crown bow shackle with pin through 10mm chain 3 links to Kong attached to 8mm g70 chain.

So if my assumption in the first question below is correct, that would make the Kong the weakest link at 5t straight pull break load, with the risk of a jaw levering side load much reduced; 6t for the Petersen shackles including a 50% discount for 90 degree load; 7+t for the main chain; 6.5t for the 10mm g40 chain link. Which is not perfect but seems as good as I am going to get while still being able to reliable get the whole through the boats 50mm wide stem slot anchor roller.

My questions.

Peterson certify WLL 2t for the 10mm shackle, with a safety factor of 6 - does that mean a notional break load of 12t?

Wichard say their 17/4 shackles are not to be used for mooring purposes. Given that Vyv has successfully used one of those for years, I assume this means not for permanent immersion and that anchoring should be fine?

The Petersen pins do not appear to be self locking like the (weaker) Wichards - do I use permanent or medium loctite?

D shackle with pin through anchor shank is a big no no. Bow shackles are termed anchor shackles for a reason. Pin through the shank is not what shackles were designed for. You need a bigger bow roller

 

[stranded]

You need a bigger bow roller

Thanks. The roller is through the stem - I’m not butchering that. And the bow of a shackle unless ridiculously undersized will not go through the hole in the anchor shank. It is what it is.

The boat has sailed in the UK, the Caribbean and the Med for 16 years in sometime challenging conditions with the Kong swivel attached direct to the anchor without problem. This is suboptimal and I am trying to see if I can improve on it, not perfect it.

I think I have the information I need now and I think it will be an improvement, so I will go with that.

 

[thinwater]

Without writing a whole essay about it, why not attack the round hole in the anchor with a drill and file, and make it a slot. That would save a lot of grief.

I think I could come up with a few examples of strong anchors with round holes pretty easily. CQR. Original Bruce. Most admiralty or stockless ship's anchors. Granted, they came with beefy shackles included. But I think we can eliminate stupid as a reason, because these were all designed by smart guys. I think you have to look at the cases separately. Most anchors are better off with a slot, but without knowing all the facts, modifying an anchor wouldn't be my first step.

As for flipping devices or swivels that attach dirrectly to the anchor, why would you want something that changes the geometry of the anchor when pulled t o the side? Inserting a few links to insure full articulation is smarter.

 

[Neeves]

I had noticed and condemned, in my mind, the reduction in width of bow rollers. Its maybe an example of accountants paring costs too much. There seems little point in a bow roller that cannot actually be used.

There is another alternative.

I watch and listen to people retrieving their anchor and they run the windlass flat chat until the anchor drives at speed into the bow roller. This might not harm the bow roller but it will certainly stress the windlass, its seals and the gearbox.

We had a very wide bow roller, generous by any standards but moments of inattention and the anchor would hoist itself over the roller itself and stop when the shank hit the roller. We added markings to the chain, stopping when the marks arrived at the bow roller and then retrieving the last metre of chain and the anchor by hand. If you are reasonably fit this is not difficult - maybe upto a 25kg anchor. We would then secure the anchor. We used the same short strop with a chain hook that we used as a back up should the snubber fail - it takes the tension off the windlass. So retreive by hand the last metre of chain and the anchor. If retrieving the anchor by hand you are lifting the shackle above and over the bow roller - the shackle never needs to touch the bow roller, at all. In mud the anchor would be lower and allowed to dangle in the water and be washed as the yacht moved out of the anchorage (and then retrieved by hand). It did help, for us (as complete wimps, that we used 8kg aluminium anchors and 6mm chain.

The other answer is to look at those smaller Peerlift G80 shackles - might they be the solution? Bow shackles, highly tested, along with Crosby et al - the best that money can buy. I have a 1/4" version and you cannot tell me (though you might) that its too big to pass through your bow roller - but not knowing the size of your bow roller nor the spec of your chain - I'm guessing (which is what we all have been doing in the absence of a picture, size and specs). But its your yacht.

You are not alone with a yacht with a narrow bow roller it would be nice to have a neat and cost effective solution. Throwing money at a problem seldom comes up with the best compromise. You seem to be focussing at a Rolls Royce solution for a pretty ordinary anchor which only has a circular hole for the shackle (which is bound to be side loaded). The anchor 'may' have a shank (is it an original Bugel?) designed to be side loaded I wonder what shackle they expected owners to use? - most other anchors with holes instead of a slot use monster shackles (for the obvious reasons) - like my original Scottish CQR. Interestingly the original shackle is a very long 'D' shackle. Manson's Ray (poor Bruce copy) also has a hole as do Guardians.

A final comment all the ironmongery needed to join anchor to rode is all reducing the ability of the anchor to dig deep and develop maximum hold. Most anchor makers recognised this aspect of rode design and are using high tensile steel in the shank allowing the shank to be thin. Its carried further with Viking who use HT steel in the fluke reducing its resistance to burial and Rocna with the Rocna 2 have replaced the round roll bar with a ribbon of steel (which also increase area to add to hold). Adding big shackles, lots of shackles, larger chain, a swivel all detract from the performance of the anchor.

I had recognised a long time ago that chandlers are more than happy to sell HT G70 chain - but none of them bother to cater for the attachment of the chain to the anchor - its all upto the owner to sort out. Its not simply about the chain but getting all the bits and pieces, which should be few, to allow the anchor to be joined to the chain. I go through this with every chain with which I am involved and have a project on now for a 40' cat whose owners plan to liveaboard for the next 3 years exploring the Pacific. The options centre round Gunnebo's galvanised G80. Fortunately the cat is in build and there is free choice of bow roller, windlass, snubbers and snubber layout.

Jonathan

 

[RunAgroundHard]

D shackle with pin through anchor shank is a big no no. Bow shackles are termed anchor shackles for a reason. Pin through the shank is not what shackles were designed for. You need a bigger bow roller

What about a D shackle through the anchor shank and pin through chain? Or what about a bow shackle with the pin through the anchor shank? Are any of these options a "no, no"?

 

[boomerangben]

Thanks. The roller is through the stem - I’m not butchering that. And the bow of a shackle unless ridiculously undersized will not go through the hole in the anchor shank. It is what it is.

The boat has sailed in the UK, the Caribbean and the Med for 16 years in sometime challenging conditions with the Kong swivel attached direct to the anchor without problem. This is suboptimal and I am trying to see if I can improve on it, not perfect it.

I think I have the information I need now and I think it will be an improvement, so I will go with that.

I apologise for not reading your previous post carefully enough. You did say it’s a stern roller and narrow. Over the weekend, I did some calculations to see what side loads are put into shackles used as you plan and was quite surprised. The leverage is substantial and an offset of only about 20 degrees will cause a load trying to seperate the cheeks of the shackle equal to the load being applied. Your anchor shank is effectively a crow bar, levering the shackle apart. That is why Neeves stresses the much lower strength of a shackle when side loaded.

Going for a bigger shackle will help to a certain extent, but without knowing the geometry of the anchor/shackle connection and the size of your boat, it is impossible for anyone to say that your set up is strong enough or not. If what you have decided to use helps you sleep at anchor, then it’s good enough.

From the various different authorities on how much load goes through an anchor warp it appears that for a 35’ boat it will be less than a tonne. Indeed Neeves (IIRC, Neeves, if you read this please correct me it up I’m wrong) writes of a test where they stopped testing when they experienced a load of about 600kg for fear of damaging the boat. If you can prevent shackles jamming, you would never need anything bigger than a 1te shackle for that size of boat. If you are only ever anchoring in benign conditions, a 0.5te shackle would be strong enough. It will look pathetic, but it would do the job. We need to over size unless we do something to prevent the shackles being cross loaded.

Finally, if you are using G70 8mm chain, its breaking load is over 7te. Imagine having 7 builders bulk bags of sand hanging off your stern. In fact imagine two bags hanging off your stern. Imagine the effect that would have in your trim and stability. Imagine what effect that would have on your roller, India’s, cleats etc. if I was in a boat that was experiencing anything like those loads in my anchor chain, I would be running for better cover or calling for a rescue.

 

[boomerangben]

What about a D shackle through the anchor shank and pin through chain? Or what about a bow shackle with the pin through the anchor shank? Are any of these options a "no, no"?

To be clear, I used to design lifting systems for offshore construction. We only ever used bow shackles because D shackles are designed for in line loading. They are not supposed to take any bending. I did some maths on how much leverage a 3/4 te bow shackle would be subjected to by my fortress FX7 (pin through shank) over the weekend. Essnentially with a 20 deg offset, the shank was acting like a crow bar trying to apply the same load trying splay the shackle as was in the rode load. It depends on the specific geometry of the shackle - shank combination. So in theory, I would say you always should strive to put a bow shackle through the slot of the shank and pin through the last link in the chain. If you can prevent the shackle becoming jammed, you don’t need a very big shackle since anchoring loads for leisure boats up to 40’ are only ever over a tonne in survival conditions. But of course if you choose to use a much bigger shackle than the anchor loads, you might get away with it, but it’s difficult to prove that the shackle is in fact strong enough without testing it.

 

[RunAgroundHard]

To be clear, I used to design lifting systems for offshore construction. We only ever used bow shackles because D shackles are designed for in line loading. They are not supposed to take any bending. I did some maths on how much leverage a 3/4 te bow shackle would be subjected to by my fortress FX7 (pin through shank) over the weekend. Essnentially with a 20 deg offset, the shank was acting like a crow bar trying to apply the same load trying splay the shackle as was in the rode load. It depends on the specific geometry of the shackle - shank combination. So in theory, I would say you always should strive to put a bow shackle through the slot of the shank and pin through the last link in the chain. If you can prevent the shackle becoming jammed, you don’t need a very big shackle since anchoring loads for leisure boats up to 40’ are only ever over a tonne in survival conditions. But of course if you choose to use a much bigger shackle than the anchor loads, you might get away with it, but it’s difficult to prove that the shackle is in fact strong enough without testing it.

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.

 

[Neeves]

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.

Except that your CQR has a shank that moved with the veers and had a fluke that was renowned for moving (call it dragging). However this might be unkind - we are now used to having anchors that stay where they are set as a result of improvements in design.

The OP has an anchor that he praises for its reliability, which implies - it does not move.

From the various different authorities on how much load goes through an anchor warp it appears that for a 35’ boat it will be less than a tonne. Indeed Neeves (IIRC, Neeves, if you read this please correct me it up I’m wrong) writes of a test where they stopped testing when they experienced a load of about 600kg for fear of damaging the boat.

I can confirm under a ton, I measured 650kg as a snatch under a 35 knots gust and was unaware how such forces might impact the yacht - and frankly I was scared and terminated the test.

All credit to your memory.

Jonathan

 

[RunAgroundHard]

Except that your CQR has a shank that moved with the veers and had a fluke that was renowned for moving (call it dragging). However this might be unkind - we are now used to having anchors that stay where they are set as a result of improvements in design.

The OP has an anchor that he praises for its reliability, which implies - it does not move. ...

The shank of the CQR does not move with the veers, it flip flops either side of the centre line of the plough. Could the CQR turn in the mud, of course, but it held in place in my anchoring endeavours. The CQR was often secured with the largest bow or D that could fit over the D in the CQR. It worked for decades, including for yachts that anchored in hurricane strength winds in the south Atlantic using CQRs.

I do agree that one has to understand the WLL of their gear, but disagree with the "no, no" claim about using D shackles.

 

[Neeves]

Thinwater and I have discussed the problem raised in this thread, endlessly. However we have not had the restriction in our ongoing debate of a specific anchor nor a restrictive stem roller. We also knew the quantitative data for what we had and wanted.

G70 chain, genuine G70 chain, is a welcome addition to those yacht owners who want to save weight. However you do need to be careful to ensure that you match the rest of the rode, specifically shackles, with the strength of the chain. 8mm G70 chain has a UTS of 7t ensuring that your chain is the weak link (its the most expensive component) is a real challenge - completely ignored by the salesman selling you the chain (its expensive and a sales coup).

When I investigated my HT chain I included all the components as part of the work - so I included shackles, chain hooks, my Boomerang, swivels, chain hooks and anchor shanks. I tried to make all the tests, relevant, so under my interpretation of 'our' conditions so not necessarily standard testing protocols. My conclusions were, bow shackles viz Crosby 209a shackles, Peerlift G80 shackles or Campbell Orange pin shackles paired with G100 Omega links, my boomerang and as we owned a catamaran my bridle plate. Down sizing chain sacrifices catenary so a snubber investigation became yet another topic (and more articles) My boomerang was not original and leant heavily on NormanS bent link and Oscalutti's similar bent link. The bridle plate also lacked originality - I just refined it, a bit. Use of climbing rope for snubbers was another concept I borrowed.

I was fortunate: I did not have a narrow bow roller and was willing to try a variety of anchors.

The conclusion to my investigation was a series of articles and a rode where the chain was the weak link but its 6mm strength was better than the 8mm it replaced. All the components were stronger than the chain and all the bits and pieces match, fitted together. Everything was tested to destruction using a NATA testing facility.

Down sizing chain is easy - its just money. Down sizing a rode is much more complex.

I have not altered my conclusion but added Yoke to my preferred shackles and I have refined the bridle plate.

Its not easy - but without the numbers - we are guessing. I might have missed it but I have not seen the restrictive size of the bow roller nor do I know if its a genuine G70 chain - so I'm still guessing

Jonathan

 

[stranded]

I apologise for not reading your previous post carefully enough. You did say it’s a stern roller and narrow. Over the weekend, I did some calculations to see what side loads are put into shackles used as you plan and was quite surprised. The leverage is substantial and an offset of only about 20 degrees will cause a load trying to seperate the cheeks of the shackle equal to the load being applied. Your anchor shank is effectively a crow bar, levering the shackle apart. That is why Neeves stresses the much lower strength of a shackle when side loaded.

Going for a bigger shackle will help to a certain extent, but without knowing the geometry of the anchor/shackle connection and the size of your boat, it is impossible for anyone to say that your set up is strong enough or not. If what you have decided to use helps you sleep at anchor, then it’s good enough.

From the various different authorities on how much load goes through an anchor warp it appears that for a 35’ boat it will be less than a tonne. Indeed Neeves (IIRC, Neeves, if you read this please correct me it up I’m wrong) writes of a test where they stopped testing when they experienced a load of about 600kg for fear of damaging the boat. If you can prevent shackles jamming, you would never need anything bigger than a 1te shackle for that size of boat. If you are only ever anchoring in benign conditions, a 0.5te shackle would be strong enough. It will look pathetic, but it would do the job. We need to over size unless we do something to prevent the shackles being cross loaded.

Finally, if you are using G70 8mm chain, its breaking load is over 7te. Imagine having 7 builders bulk bags of sand hanging off your stern. In fact imagine two bags hanging off your stern. Imagine the effect that would have in your trim and stability. Imagine what effect that would have on your roller, India’s, cleats etc. if I was in a boat that was experiencing anything like those loads in my anchor chain, I would be running for better cover or calling for a rescue.

Thank you for taking the time to explain this Ben. My boat is 44ft and about 13t in cruising trim. We aim now only to anchor in moderate conditions, and will run for cover if more than 30kts is expected, but the sea will spring surprises.

Really it comes down to a choice between not great options - crow barring the Kong jaws, with a claimed break load of 2t, or likewise the sides of a shackle with a claimed break load of 12t, so 6t applying the 50% strength reduction formula for a 90 degree angle pull. No one seems to know if this latter formula is accurate for a d shackle, but to bring the shackle break load down to that of the Kong the strength reduction with a 90 degree pull would have to be c. 84%. That seems a lot.

Ideally of course the answer would be none of the above, but hey ho.

 

[NormanS]

I think I could come up with a few examples of strong anchors with round holes pretty easily. CQR. Original Bruce. Most admiralty or stockless ship's anchors. Granted, they came with beefy shackles included. But I think we can eliminate stupid as a reason, because these were all designed by smart guys. I think you have to look at the cases separately. Most anchors are better off with a slot, but without knowing all the facts, modifying an anchor wouldn't be my first step.

As for flipping devices or swivels that attach dirrectly to the anchor, why would you want something that changes the geometry of the anchor when pulled t o the side? Inserting a few links to insure full articulation is smarter.

Maybe you have picked up the wrong end of the stick? For years, I used a genuine, made in Scotland, CQR. It had a slot, and I've never seen one with just a hole. I now mostly use a genuine Bruce, and again it has a slot, and I've never seen one with a hole. Maybe things are different in the USA.
My bent link is not connected direct to the anchor. I don't know where you got that idea. There are three links between the link and the anchor.

 

[Neeves]

I do agree that one has to understand the WLL of their gear, but disagree with the "no, no" claim about using D shackles.

I actually cannot think of a reason to have a galvanised 'D' shackle on a yacht at all, other than the CQR, Guardian etc exceptions. I would not aggressively suggest 'D'shackles are a No! No! - just except for specific application (which did not apply to us) they had no use.

I can think of reasons to have a galvanised bow shackle on a yacht.

I try to persuade people not to buy bow shackles from the local hardware store - I don't know how many listen. But having a shackle from a nefarious source or one inappropriate for the only application I can think of, the anchor rode, leaves opportunity for mistake. I suggest that people only carry reputable bow shackles, nothing else. I stress the plural, having dropped the clevis pin of a Crosby 209a shackle over board

The ends of our 6mm chain, the main rode and the second (mixed) rode both had permanently attached omega links, each of our anchors, spares and main had their own shackles, all 3/8th" all 2t WLL and already attached to the shank.

Good bow shackles are not expensive.

Jonathan