Extra Long Anchor Shackle

[Nomad Willy]

Quote:
Originally Posted by Xsbank
Pete, I think you should lose that long stainless shackle. Not only is it non-rated, it has a very long moment that could cause it to fail if you pull your anchor sideways. Personally, I have ditched all my swivels too as once the anchor releases the bottom the chain makes it unwind so a swivel is just another point of failure (swivels are almost as controversial as anchors...).

I do think that shackle is risky...

No issue at all XBank. The set-up is specific to the way the Super Sarca slot works. The longish shackle is over-sized, and the extra length makes it work better as a locking mechanism so that unless the direction of pull is directly above the slot, (ie, intentional), it will not slide to the fluke end and pop the anchor out prematurely on a current or wind reversal, something Marin used to fret about a lot re the tripping slot. Rex, the manufacturer, has approved my set-up. The photo is now a bit out-dtated, but as I said, swivel is long gone, and that connecting shackle is now replaced with a nice shiny (rated) new one, also slightly over-sized.
__________________
Pete


I agree w Xsbank,
I don't see how the much longer shackle will aid the direction of pull to be right above the slot. The direction of pull is a result of the rode and the position of the boat.
IMO the extra long shackle could tend to bind the shackle pin and ears and reduce the ability of the pin end of the shackle to slide down the slot. Perhaps the reason most "anchor shackles" have a very circular end is to limit and thus prevent binding to maintain reasonable loads on the pin.
The extra length is so much I fail to see how leverage on the shackle will not be excessive under sideways loads. Also the shear load on the pin could be three times as much as a typical anchor shackle pin would experience.

So don't look good to me either.

 

[Peter B]

Quote:
Originally Posted by Xsbank
Pete, I think you should lose that long stainless shackle. Not only is it non-rated, it has a very long moment that could cause it to fail if you pull your anchor sideways. Personally, I have ditched all my swivels too as once the anchor releases the bottom the chain makes it unwind so a swivel is just another point of failure (swivels are almost as controversial as anchors...).

I do think that shackle is risky...

No issue at all XBank. The set-up is specific to the way the Super Sarca slot works. The longish shackle is over-sized, and the extra length makes it work better as a locking mechanism so that unless the direction of pull is directly above the slot, (ie, intentional), it will not slide to the fluke end and pop the anchor out prematurely on a current or wind reversal, something Marin used to fret about a lot re the tripping slot. Rex, the manufacturer, has approved my set-up. The photo is now a bit out-dtated, but as I said, swivel is long gone, and that connecting shackle is now replaced with a nice shiny (rated) new one, also slightly over-sized.
__________________
Pete


I agree w Xsbank,
I don't see how the much longer shackle will aid the direction of pull to be right above the slot. The direction of pull is a result of the rode and the position of the boat.
IMO the extra long shackle could tend to bind the shackle pin and ears and reduce the ability of the pin end of the shackle to slide down the slot. Perhaps the reason most "anchor shackles" have a very circular end is to limit and thus prevent binding to maintain reasonable loads on the pin.
The extra length is so much I fail to see how leverage on the shackle will not be excessive under sideways loads. Also the shear load on the pin could be three times as much as a typical anchor shackle pin would experience.

So don't look good to me either.

Well, Eric, please don't lose any sleep over it, as it has been just fine for the last 14 years. However, you haven't got the concept I was referring to re the locking it in the slot, so I'll try to make more clear.

Imagine the scenario the anti-slot tripping folk fear, of the boat moving back over the anchor, and by chance dragging the shackle right back up the slot and tripping the anchor, when that is meant to only happen when retrieving a fouled anchor. The reason this does not happen when unwanted is because if being fouled is the problem, the tripping is achieved by the deliberate placing of the bow over the anchor and taking up virtually all slack, and deliberately moving forward over the shank to cause that shackle to slid down the slot, the shackle by this time being held more or less vertical, and trips the anchor, by reversing the fluke out, as it does if say fouled under a rock or other debris on the bottom.

Ok, if we then take the feared scenario of it happening when you don't want this. And in this case, you are exactly right when you say...

"IMO the extra long shackle could tend to bind the shackle pin and ears and reduce the ability of the pin end of the shackle to slide down the slot."

Because that is precisely what you want to happen. This is when this longer shackle does its bit, (as you say above) because the slot is square, not rounded, and unpolished, deliberately, so there is friction if the shackle is pulled towards the fluke in any other angle than from directly above. As a result, an even slight sideways angle, which is what you would expect with normal boat movement due to current/wind changes, the added leverage of the length of that shackle, (the relevant point), adds to the tendency for that shackle to, in effect, 'lock', 'jam', or 'bind', (as you said), in the slot, and not slide down to the fluke end. In this case, a desired effect. Whereas a short shackle, as one might normally use in a non-slotted shank, would cause less 'locking/binding effect', and slide down the slot easier. So, fear not, that longer shackle has taken plenty of sideways tension in it's day and has never deformed or loosened the pin.

 

[BruceK]

SARCA now seem to include a slot bolt with Super Sarca anchors. This gives the option to restrict the travel of the shackle pin and shackle, completely eliminating travel if desired, and thus eliminating the problem some people see with slot travel.

 

[sunchaser]

Bruce, I can barely grasp the reason for a slot, especially on +30 kg anchors. The bolt makes sense for anchor Luddites like me. Or better yet buy an anchor without the specious slot.

 

[BruceK]

Bruce, I can barely grasp the reason for a slot, especially on +30 kg anchors. The bolt makes sense for anchor Luddites like me. Or better yet buy an anchor without the specious slot.

Now Tom, a seasoned cruiser like you knows the idea is: on retrieve the shackle slides to the blade end, changing the lift point and anchor angle to shank down vertical, so the so well set high holding anchor can be broken free, when otherwise it might not. (Apologies to Rex Francis if I got that wrong).
Making slot use optional by including the bolt may widen appeal to someone who doesn`t want the slot system but otherwise wants the anchor design.
Be good to see comparative tests:1) with the slot bolt preventing shackle slide, and 2) with the slot operation unrestricted. Steve, are you watching?
Unreliable memory says another brand, ? Rocna, has/had both slot and conventional end of shank attachment hole.

 

[Peter B]

The slot serves two functions. Often it comes in handy to break out a very deeply embedded anchor, thus making retrieval much less demanding on the lifting gear. It really just potentiates or enhances the already common practice of motoring slowly back over the anchor to break it out.

However, fortunately less often, (but you never know when), the real benefit is for when the anchor is really fouled, and the slot still allows for recovery, (ask mo how I know), whereas with other anchors without the trip slot, unless one has routinely attached an anchor float line to the fluke end, you are probably looking at a jettisoned and probably lost anchor situation.

I found it really interesting, that in (Panope) Steve's, anchor setting videos, his constant reversing direction test saw the S-Sarca with slot open, never fail once to stay set, or re-set quickly, and from memory the slot never tripped it once in the normal reversing tests.

 

[Nomad Willy]

Peter,
Thank you much I get it.
The long shackle binds a bit and makes it at least difficult to slide down the slot for fwd anchor lifting. But when the rode is vertical or nearly so it slides to whatever end it needs to be at the whim of the skipper. Fine.

But still what I don't see solved is the weakness of the extremely long shackle. Sure w the normal anchor loads it should work fine .. just like a cheap shackle. But I can't imagine that very long shackle not at least bending under heavy side loads. Bill and Xbank expressed their concerns about this too .. Bill being the first.
Aircraft bolts are made out of a steel that I think is very tough and bends a great deal before breaking. If the ARA anchors were to equip their anchors (w every sale) with a long shackle (like what is in Peter's pics) made oversized and w the tough steel described above I would be more comfortable using it.

So if the long shackle was made to take 3-5000lbs side load l'd stand down.

But anyone thinking the shackle and slot would trip the anchor when they didn't want it too .. they should read the above again. I'd feel 100% safe with it now. But I'd probably wanna use a normal (pin in the slot) shackle.

 

[BruceK]

Eric, not sure but I think the long shackle overcomes the risk of fouling.
It needs to be a good quality shackle, I used a Ronstan, which unlike many comes with a rating. There are some shiny looking shackles out there, but the less shiny Ronstan is a good choice.
At first it seems odd Sarca supply the bolt but not the shackle. Could be Sarca doesn`t want the responsibility of selling and thereby warranting someone else`s shackle.They don`t make them, or have a hand in how they get fitted into the rode.
Peter makes a good point about anchor recovery when fouled by some object, by the use of the slot. I`d not considered that.

 

[Peter B]

Eric, not sure but I think the long shackle overcomes the risk of fouling.

Yup, that's it.

At first it seems odd Sarca supply the bolt but not the shackle. Could be Sarca doesn`t want the responsibility of selling and thereby warranting someone else`s shackle.They don`t make them, or have a hand in how they get fitted into the rode.

Again, spot on as to reason, Bruce.

Peter makes a good point about anchor recovery when fouled by some object, by the use of the slot. I`d not considered that.

Strange that, Bruce, because that, as they say...its raison d'etre...

Cheers,

 

[BruceK]

Pete, could be my schoolboy French, but I don`t see the Super Sarca as a "one trick pony"(don`t spoonerize that Tony), it has several virtues of how it works. Like some other modern anchors, it shows us there is progress since the CQR (took a while to twig why they call it CQR; say it out loud.)

 

[Peter B]

Pete, could be my schoolboy French, but I don`t see the Super Sarca as a "one trick pony"(don`t spoonerize that Tony), it has several virtues of how it works. Like some other modern anchors, it shows us there is progress since the CQR (took a while to twig why they call it CQR; say it out loud.)

Fair comment, but also Bruce, if you pronounce Sarca in the words the name is derived from, it is 'S'and, 'A'nd 'R'ock 'C'ombination 'A'nchor, which does sort of hint at the all-rounder function, and being able to be used safely in 'R'ocks, where fouling is more likely, thanks to the tripping slot..? Just sayin'...

 

[sunchaser]

The first slotted anchor I had was on a smaller SeaRay where hand retrieve was used. Maybe, just maybe it was of benefit vs no slot. I honestly could see no difference in hand retrieving vs a non slotted similar sized Danforth.

On larger vessels where a workable windlass was employed never had a slotted anchor but then again the few fouled anchor episodes were related to cables and old crab pot lines.

Once into big anchor and chain combinations where hand retrieval not possible never found a situation where a slotted anchor would be of any benefit. But no harm either. Nothing more complicated than getting the anchor chain near vertical and hitting the up arrow to break it loose.

For many of us with big anchors, all chain rode and a sturdy windlass, a slotted anchor seems nothing more than the proverbial perfect solution for a problem that doesn't exist. Doesn't mean Sarcas are bad, just means marketing hype IMHO. Sarca is too good an anchor to use the slot notion as a reason to buy it.

 

[Nomad Willy]

sunchaser,
Slot "notion" ...
You're still a nonbeliver. Sounds like religion.

Rex has always been heavy on research and testing from what I hear so I'm sure he found the long shackle works better. Perhaps I did good when I used the word "binding". The leverage of the long shackle makes it questionable structurally but the rotational or sideways force probably brings about the desired or necessary binding that limits fore and aft movement in the slot. It's probably possible the necessary binding effect could be had by putting a texture not unlike a dull file on the shank and/or the shackle. Or a shackle w a very narrow space between the two ears that the pin/bolt passes through.
I still don't like the long shackle but Rex is a very conservative man and if he says it's strong enough it probably is.

But Sunchaser surely your "big" anchor, "all chain" rode and big winch probably wouldn't save the day if you hooked a log or large cable w several tons of rocks on it. Only thing I've ever pulled up was one of the biggest tree branches I've ever seen. And that was done w a small capstan.
By the way what's a "workable winch"?

Something to ponder though is not only the problem weighing anchor but the loss of expensive chain, anchor and the possibility of being in great danger due to your inability to disengage the bottom.

Perhaps the conservative Rex has presented us w a valueable anchor feature that we are too old and conservative to accept.

 

[BruceK]

It is possible the slot is/was a marketing point of difference, but I doubt it. Rex is in business to make and sell anchors, but I can`t see him using a slot system for that reason alone. As a non engineer, the upward pull at the blade end may be more effective for retrieval, especially, as Peter says, if there is a restraining fouling object caught between shank and blade.
Many of us have experienced a fouling, it takes forever to circle around, back and forth. If it ultimately succeeds good, worse still if it doesn`t.
I don`t think Sunchaser is rejecting the anchor for its modernity as Eric suggests.
To quote Tom:
"Sarca is too good an anchor to use the slot notion as a reason to buy it."

The question then is, does the slot detract from the anchor? In my experience it does not. Even then, if I decide I don`t like it I can block the slot.
One issue with using a high quality long "D" shackle is you usually can`t connect the chain directly to the shackle as the pin ends are too big to go through the chain, and you need to introduce a further fitting to the rode. Provided that addition is good quality too it should not be a problem. Certainly has not in our case, we are quite willing to anchor, we recently had 60M of chain out in Yeomans Bay on the Hawkesbury in a gusty SE breeze, with no dramas.

 

[Peter B]

Something to ponder though is not only the problem weighing anchor but the loss of expensive chain, anchor and the possibility of being in great danger due to your inability to disengage the bottom.
Perhaps the conservative Rex has presented us w a valueable anchor feature that we are too old and conservative to accept.

CORR---RECT, Eric. Pass go, and collect $200 as you go.

However, let me just say this, just to clarify, while Rex has said he has no issue with my setup, he did intimate my shackle is a tad longer than strictly necessary for the system to work. It was just that that shackle I had was all the chandlery had that was beefy enough at the time, and as it has worked faultlessly in the past 14 years, I see no cause to change it.

 

[sunchaser]

Ahh, now I get it. The slot helps me to not lose my anchor and chain. In searching the anchor threads though I see no mention of this gear disappearing to the deep except when the fail safe tie to hull was not fail safe. The important thing though Peter is you are very happy with your anchor which just happens to have a slot in it.

 

[Nomad Willy]

Thanks Peter,
The details do make a difference.
How on earth DO you get the chain mated to that long shackle? Another shackle I suppose and any bulk at the shank end reduces (or dramatically reduces) the ability for the shank to penetrate the bottom so the negative pitch of the fluke is lost or reduced. Steve's anchor setting vids show how anchor shanks pitch down into the seafloor positioning the fluke in a very pitch down attitude promoting more and better penetration. That's why I attach a short wire rope to my shank end. Shackles and chain don't slide into the seafloor very well. My short chain is two sizes larger that usually employed on a W30 so I don't want it next to the shank end. It is (on my rode) about 3' uprode from the shank. I'll probably have dificulty extracting my anchor at times because of this. I learned this from the XYZ guy. But I may not want to overset on known soft bottoms.

I've shown this pic before but it's very relevant to the text above. The shackle on the shank is very small too. I have a 12lb home made kellet or anchor buddy that can be attached to the boat end of the chain.
The bow line looks a bit like it's part of the rode, it's not. Things just lined up wrong.

 

[Peter B]

Thanks Peter,
The details do make a difference.
How on earth DO you get the chain mated to that long shackle? Another shackle I suppose and any bulk at the shank end reduces (or dramatically reduces) the ability for the shank to penetrate the bottom so the negative pitch of the fluke is lost or reduced.

Actually, Eric, yes, another slightly smaller shackle, and your comment above, in real life, appears to be absolutely irreverent - also irrelevant. Doesn't stop it burying whatsoever, judging by the amount of mud that sometimes comes up all over it, but which fortunately washes away nicely by a wee drag just under the surface as we move off. Something that experience has taught me to nearly alway do as a result. So Eric, please lose no more sleep over shackles or whatever stopping shanks from burrowing in. The forces involved make that a non-issue. However, in most situations, the Sarca exerts such stopping power even with just the full fluke buried, the boat seldom gets to exert enough force to bury the shank as well unless a real heavy situation arises in my experience.

 

[BruceK]

Eric, I touched on the shackle/rode connector issue in post 14 above. Unfortunately the anchor designer/manufacturer/seller isn`t here to help with these issues but Peter does very well filling the void.
I once spent nearly an hour helping a friend maneuver around his fouled CQR, luckily we freed it, but if the vertical slot pull overcomes the fouling cable or whatever,just once, it`s worth it, assuming the slot create other mischief which outweighs the recovery advantage. I know the PO of my boat lost a fouled anchor, it does happen. Most carry a backup anchor and rode ready to go, one reason is potential anchor loss due to non recovery.

 

[Nomad Willy]

The slot is a non-issue.

Unless you want to talk about how it works (or dosn't) or reap benefits from it the slot is a non issue. I have one on my Supreme as you can see but usually have it bolted off.
Peter dosn't belive it but but the bulky gear (shackles, chains ect) do impeed the penetration (to a relatively small degree (and mostly in soft bottoms))of the shank. Mostly in a downward knife slicing way. Also the extra leading edge face (inside the slot) dosn't help either. Details do matter but to varying degrees. There are details. The slotted shank is heavier for it's strength. It presents more lateral resistance during veering. It costs a bit more to manufacture. But these issues (if they can be called that) are very small issues. But they do exist and we don't really know to what degree. Analyzing requires considering many variables and contemplating some variables leads us to more variables that do or may have a greater effect. Some anchors like the old forged Danforths have very slender shanks. The main reason is so they will slice down into the seafloor allowing the important part (the fluke) to penetrate also. With the fluke down we can get results. That applies to all anchors.

Interestingly I plan to eliminate the top part of the shank of my Supreme (and thus the slot) and do several other slight modifications as well. Steve (Panope) talked about cutting out that upper part of the shank also and it was his idea so he should get any credit due. What I am loosing sleep over is whether or not to do more testing of the anchor as it is or dive in and make the other mods now.

But all details aside I would'nt let the slot derail my purchase of the SARCA.