“Twisted” & “Reinforced Super Strength” Soft Shackles

[Breaking Waves]

Interesting, useful photo.

I guess what you are doing might be described as making a stable two-strand braid.

I have no experience testing anything like that construction.

I personally would just be cautious unless/until I broke a bunch of them. As I have mentioned in the past, I am often surprised at the results when I break a new construction.

But it IS interesting - I never would have guessed that it would hold like that.

[s/v Jedi]

People are confused because of the initial twisting but it untwists when it is doubles up and forms a wound spiral shape.

The ability to enlarge the loop for easier opening and closing is also the weakness of the design (I think). When an eye splice is used like I described, it becomes impossible to open under load so it needs to be slack to open.

The spiral shape will tend to unwind under tension because it becomes longer ... and this will enlarge the loop. Tension should still prevent the stopper knot from slipping through but in destructive testing I think it’s possible it gets out before something breaks.

For the intended purpose I’m sure it performs beautifully

[Seaworthy Lass]

Originally Posted by Breaking Waves

Interesting, useful photo.

I guess what you are doing might be described as making a stable two-strand braid.

I have no experience testing anything like that construction.

I personally would just be cautious unless/until I broke a bunch of them. As I have mentioned in the past, I am often surprised at the results when I break a new construction.

But it IS interesting - I never would have guessed that it would hold like that.

Yes, a “stable two-strand” sounds like a good description. If a multiple stand line is unravelled, the strands end up severely twisted, yet they just curve when part of the rope.

I mentioned earlier that this has not been load tested. I am only guessing at failure point, but I will eat my hat if it is anything other than the base of the Diamond or the eye. It would also surprise me greatly if at least line strength was not achieved.

I would love some load testing gear. I test items out between our hefty winches and I can break lightweight line, but I know that designs will not necessarily behave the same way for thin line, so any conclusions are limited.

Unless load tested I suggest this design is only used for very lightweight duty, but I think testing will show that it will have some potential when for whatever reason UHMWPE is not available and a soft shackle is needed.

[Breaking Waves]

I made one.

There is twist in mine right at the head of the loop. As with yours it does not appear twisted down the body. Double braid might well be more twist-resistant, and better for this construction, than this loose single braid I used (just what I had immediately around).

and the loop is pretty big, quite loose under the knot, I would not think secure. I could have used a bigger stopper knot design I guess

But that might all be my construction error rather than a design error.

I used a drill to create the original twist, put in a ton of twist - needed to pull it straight while running the drill to prevent it from all balling up/hockle. But perhaps that was not enough

[Seaworthy Lass]

Originally Posted by s/v Jedi

People are confused because of the initial twisting but it untwists when it is doubles up and forms a wound spiral shape.

The ability to enlarge the loop for easier opening and closing is also the weakness of the design (I think). When an eye splice is used like I described, it becomes impossible to open under load so it needs to be slack to open.

The spiral shape will tend to unwind under tension because it becomes longer ... and this will enlarge the loop. Tension should still prevent the stopper knot from slipping through but in destructive testing I think it’s possible it gets out before something breaks.

For the intended purpose I’m sure it performs beautifully

I would bet the stopper will never slip through the eye while under load, and I usually have no gambling tendencies .

From what I have observed, under load the twists definitely have no tendency to unravel. They elongate, but the number of twists remains exactly the same. I have no engineering background, but I can also see no reason why the number of twists would decrease under load. I am scratching my head to see why this would occur.

Given that the length increases under load, the eye also becomes longer, but at the same time it also narrows, gripping the sides of the base of the soft shackle more firmly. So I think the risk of the stopper coming out is when not under load, particularly if the load is cyclical, just as it is for any soft shackle. If anything though, the twists force the eye into a certain shape and size and flogging seems to do little to alter this, so I would guess the risk of the eye inadvertently opening is less that for a conventional soft shackle eye.

Care does need to be taken to induce sufficient twists to create an eye that is not too large. At least it is easy to add more though if the eye looks too large when the twisted legs are smoothed evenly.

Soft shackles from UHMWPE are by far superior, but it would be nice to have a design that functions in double braid polyester (or any other softish material). Testing would of course be needed before this design is used for anything other than light loads though.

For now I think it is a useful way of using scrap lengths of line for hanging items.

[Seaworthy Lass]

Originally Posted by Breaking Waves

I made one.

There is twist in mine right at the head of the loop. As with yours it does not appear twisted down the body. Double braid might well be more twist-resistant, and better for this construction, than this loose single braid I used (just what I had immediately around).

and the loop is pretty big, quite loose under the knot, I would not think secure. I could have used a bigger stopper knot design I guess

But that might all be my construction error rather than a design error.

I used a drill to create the original twist, put in a ton of twist - needed to pull it straight while running the drill to prevent it from all balling up/hockle. But perhaps that was not enough

Attachment 237986

Fascinating isn’t it .

The number of twists you induced is not enough though. That is why the eye is so large. I also found when trying the design in single braid it took time to smooth the line so the twists sat evenly and the line was not twisted on itself. It worked far better in double braid (I tried 3mm and 8mm) and paracord, which has a braided cover over straight core.

I have been playing with how best to achieve the twists and I found it easier to double the line over first, hold onto the line just below the apex between two fingers, then with your other hand twirl the apex around. The lines between your fingers (and the working ends) then spin around and twirls form above your fingers. The number of twists can be far better controlled. As the number of twists determine the final eye size, this is helpful.

I will photograph what I mean in a minute.

[thinwater]

Even simpler, I can tie this one in about 15 seconds (I have used this type to secure gear and tarps for decades and I have never had one shake loose):

• Double the line and tie either a double overhand (good) or ashley stopper knot (better) (AKA oysterman's stopper).
• Tie an overhand loop in the other end, just large enough to pass the stopper knot.

I've even used this on jibs.


You can also make an adjustable length version using old cover:

• Splice an followed by a series of loops, each just large enough to pass a stopper knot. Form them using brummel locks. Use ONLY the cover of the rope.
• Tuck the remaining cover inside to make the tail like a full rope.
• Tie a stopper in the tail.

I've used this for sail ties. Unlike knots, they can't freeze, and because the covers are from old ropes, they're free.



There must be many dozens of strop variations.

[Seaworthy Lass]

Originally Posted by thinwater

Even simpler, I can tie this one in about 15 seconds (I have used this type to secure gear and tarps for decades and I have never had one shake loose):

• Double the line and tie either a double overhand (good) or ashley stopper knot (better) (AKA oysterman's stopper).
• Tie an overhand loop in the other end, just large enough to pass the stopper knot.

I've even used this on jibs.


You can also make an adjustable length version using old cover:

• Splice an followed by a series of loops, each just large enough to pass a stopper knot. Form them using brummel locks. Use ONLY the cover of the rope.
• Tuck the remaining cover inside to make the tail like a full rope.
• Tie a stopper in the tail.

I've used this for sail ties. Unlike knots, they can't freeze, and because the covers are from old ropes, they're free.



There must be many dozens of strop variations.

Thanks for sharing these.

Yes, there must be dozens of variations. Nothing I had come across before had an eye that could be opened and “closed”.

I forgot to mention earlier that any kind of bulky stopper with a decent sized base can be used if you don’t wish to tie a Diamond knot, although the performance may be worse for slippery materials if subject to higher loads.

eg An Ashley stopper tied using both the working ends together produces a neat stopper with a flat base of good bulk. I made this one a few days ago:

[Seaworthy Lass]

Originally Posted by Breaking Waves

I made one.

There is twist in mine right at the head of the loop. As with yours it does not appear twisted down the body. Double braid might well be more twist-resistant, and better for this construction, than this loose single braid I used (just what I had immediately around).

and the loop is pretty big, quite loose under the knot, I would not think secure. I could have used a bigger stopper knot design I guess

But that might all be my construction error rather than a design error.

I used a drill to create the original twist, put in a ton of twist - needed to pull it straight while running the drill to prevent it from all balling up/hockle. But perhaps that was not enough

Attachment 237986

Below are a series of photos showing a method I have found better for inducing the twists rather than the one I described in the first post.

1. Double the line, form a small eye at the apex and grip in between two fingers.
2. Use the other hand to hold the eye and twist it. Let the line freely rotate between your fingers as the twists are induced.
3. Continue until the required length is reached.
4. When you let go of the apex the twists will not unravel.

The eye looks too small, but I found it best to make the eye a bit smaller than finally wanted, as it is hard to maintain the correct twists near the stopper while tying it. The twists and therefore the eye lengthen once the stopper it tied and tightened and the eye size ends up about right.

It is super quick and easy to do.

SWL

[Breaking Waves]

That is a better twisting technique - it eliminated the rope twist in my loop. You may be more dexterous one-handed than I am, but for me, I would suggest placing the loop over a nail (or or in a vice - or any similar way to hold it) so you can use two hands to do the twist/braid.

I'm still not super happy with the loop. It is just way looser than I am used to. I would be tempted to use the old technique of using a rubber o-ring to snug the loop up to the knot.



I have not made diamonds in quite a while - had to relearn it.

[Seaworthy Lass]

Originally Posted by Breaking Waves

That is a better twisting technique - it eliminated the rope twist in my loop. You may be more dexterous one-handed than I am, but for me, I would suggest placing the loop over a nail (or or in a vice - or any similar way to hold it) so you can use two hands to do the twist/braid.

I'm still not super happy with the loop. It is just way looser than I am used to. I would be tempted to use the old technique of using a rubber o-ring to snug the loop up to the knot.

Attachment 238018

I have not made diamonds in quite a while - had to relearn it.

A few more twists will ensure a smaller eye.

I tried securing the apex and twirling the ends, but I had less success as I found it hard to allow the ends to freely rotate so that they ended up lying straight. If they did not lie straight as soon as I let go the legs simply untwirled to accomodate this. That wasn’t a big problem, it only meant that I had to move the twists up and add more until the eye looked right.

I think anything goes as long as the final number of twists is sufficient to ensure a small eye. Giving the legs a bit of a shake or sweeping your hands up and down them a few times immediately equalises them nicely and if the eye size is not right add more twists before tying the stopper.

An O-ring would work, but I think it is nice to keep these as simple as possible. Less fuss.

[Seaworthy Lass]

PS I think I also prefer using a larger eye than you do. I make this large enough to hold 6-8 lots of line when tying a Brion Toss Button stopper (the stopper I usually use), not 4. The eye is still very much smaller than the stopper size so I think the risk of the stopper slipping through is near non existent, and importantly under load the base of the eye just sits better. It also means there is room for error if the legs do not end up shifting in length equally following pretensioning. An eye that is too small makes a very poor soft shackle.

So although I agree your eye looks too large, I think my ideal size would be bigger than your ideal.

[Seaworthy Lass]

This design may give the possibility of strengthening the eye more easily in “high strength” soft shackles. A tapered core of about 30x line diameter in length could be fed into the apex.

The twists did not sit as well in single braid compared to double, but it will be an interesting exercise seeing if this is feasible.

[Seaworthy Lass]

10pm here, but I couldn’t resist having a go and making one .

It worked surprisingly well. There was no problem burying the legs in the twisted sections. It used a softer Dyneema in 3 mm. All my thicker diameters are quite stiff either due to the anti abrasion coatings or heat stretching so they do not lend themselves well to this technique.

I will photograph it in the morning. It is too dark at the moment.

[Brocky II]

I recently came across another way of making a soft shackle by just using a loop with the stopper knot and forming a girth hitch with the end of the loop and insert the knot through the girth hitch loop. Found it on a paraglide website, commercially available as the Gin Soft Shackle, their stopper is a complicated overhand and bury. Apparently it doesn’t need much for stopping as the girth hitch clamps down on itself.