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Old 06-08-2017, 06:56   #61
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Re: How to tie a Diamond Knot

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Originally Posted by arsenelupiga View Post
button knot appears anything but safe, but sure looks pretty. Before one tightens it, cap can be pulled 'out' and there is no knot left.

As it is difficult to tighten button knot to the same level as diamond, chance of dyneema shackle slipping under tension and inverting button and get undone is high.

diamond does not have this issue.
Brion's button does need careful dressing. This was actually one of the stumbling blocks for me when I initially tried tying it (that and exactly where to poke the ends in at the last step). However, once dressed, it tightens as easily as the Diamond. No more pulls are needed as you work your way around. My buttons feel like concrete before they are pretensioned using a winch.

The importance of dressing a knot properly is underestimated in general. Few knots will perform well if this is not done. The Zepellin bend is one rare exception.

This was brought to my attention when a bowline took on the weirdest configuration once when heavy load was applied after it had not been fully tightened up. I looked at the result in absolute horror, even cutting it open (it could not be undone) to see if I had made an error tying it. I hadn't. Ashley actually commented on the importance of dressing knots, but I think few people realise this.

So I would certainly not agree that Brion's button is "anything but safe". Take a bit of care dressing it well and it is brilliant. Dress it poorly and it will fail like most other knots will.

SWL
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Old 06-08-2017, 07:06   #62
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Re: How to tie a Diamond Knot

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Originally Posted by Juho View Post
Here's one more knot for discussion. It is at least big. Doubling ensures this. The role of doubling is also that the other rope segment maintains the structure of the knot when the other segment dives through the knot. This knot has button style / four legs in one direction (to hide the working ends and to increase turning radius). It has some connection to flipping since the "through the knot legs" are the standing ends. It is about as symmetric as a button knot can be.

Picture 1 starts the process from a carrick bend. In picture 2 the ends are brought up through the middle of the knot, but unlike in the diamond knot, they do not need to go around the standing ends (the knot gets uglier if you do that). In picture 3 the knot is tightened a bit. Note how the working ends come up from the edges of the knot. You may need to bend the "hem" of the knot downwards twice to reach this form. The working ends lie now next to the incoming (through the knot) standing ends. In picture 4 the knot has been doubled so that the working ends follow the standing ends (in reverse direction), starting where the working and standing ends met each others. When the ropes are about to start third parallel round, don't do that but dive through the knot towards the standing ends.

When doubling, the working end can follow the standing end either above or below it. The knot may be a bit prettier when the working end is below (towards the standing part) the standing end. You can tie it also so that one working end is above and the other one below its standing end.

This knot is quite large. It could be useful in soft shackles that use a thin rope (that may be tied in multiple loops instead of only one).
Juho, that looks excellent! I will have a go making it when I get home tonight.

That may be super useful for thin line. One thing stopping me using thinner dyneema for soft shackles is that the stopper becomes too small to handle comfortably.

------

Just one comment before I dash off. Your first button using an inverted Diamond transforms to the weirdest configuration if you play with it (leaving the weave the same). You are left with swirls going around a Carrick. The working ends don't pass through the centre of the Carrick at all, so the hallmark of a Diamond is lost. I will tie and photograph it tonight. It is interesting to see.

SWL
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Old 06-08-2017, 08:27   #63
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Re: How to tie a Diamond Knot

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Originally Posted by StuM View Post
How "high" a chance?

Does anyone here know of any instance where a suitably pre-tensioned soft shackle button has inverted and failed. It's certainly never happened to me and I've never heard of this happening to anyone else.
I have tested a number of 'pro made' diamonds which were not sufficiently tensioned and the tails pulled into the knot, and untied the diamond, well before the shackle breaking strength.

I have never seen a button invert, even those tied by the exact same 'pros' as made the poorly tensionned diamonds above. The vast majority of the buttons I tested have had buried tails - so dont know as much about the behavior of non-buried buttons - but seems like if you are using a button you might as well bury.

I dont use the button currently in my highest strength shackles because from engineering and quality consistency perspectives it is a complicated object, the internal properties of which I dont really fully understand, and which introduces significant variability into my test results at the vest highest strength levels. A simpler construction is (turns out to be) better when you are aiming for consistency at highest possible strength.
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Old 06-08-2017, 09:52   #64
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Re: How to tie a Diamond Knot

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Originally Posted by Seaworthy Lass View Post
Just one comment before I dash off. Your first button using an inverted Diamond transforms to the weirdest configuration if you play with it (leaving the weave the same). You are left with swirls going around a Carrick. The working ends don't pass through the centre of the Carrick at all, so the hallmark of a Diamond is lost. I will tie and photograph it tonight. It is interesting to see.
I think I found it
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Old 06-08-2017, 10:30   #65
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Re: How to tie a Diamond Knot

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Originally Posted by Seaworthy Lass View Post
Brion's button does need careful dressing. This was actually one of the stumbling blocks for me when I initially tried tying it (that and exactly where to poke the ends in at the last step)...
I'm way out of my depth commenting on this thread, but this may help someone who may be quietly following: I couldn't get the correct place to 'poke the ends in' either (button knot), so I poke a long, blunt-end, threading needle up through the fingers holding the standing ends and work around it. Makes life easy (that, plus marking one tail with coloured marker pen to differentiate which end I'm pulling; darned nuisance to have to undo it when it's done wrong!).
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Old 06-08-2017, 10:36   #66
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Re: How to tie a Diamond Knot

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Originally Posted by estarzinger View Post
I have never seen a button invert, even those tied by the exact same 'pros' as made the poorly tensionned diamonds above... I dont use the button currently in my highest strength shackles ... A simpler construction is (turns out to be) better when you are aiming for consistency at highest possible strength.
So, which simpler construction knot do you use?
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Old 06-08-2017, 13:52   #67
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Re: How to tie a Diamond Knot

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Originally Posted by Juho View Post
Here's one example where the direction of the diamond knot (direction of the "through the knot legs") has some influence. I modified the diamond knot by turning the working end legs towards the standing end, making it more like a "button knot" (where the working ends point to the same direction as the standing ends, and can be buried inside them).

Picture 1 is similar to the first picture of post #41. In picture 2 the working ends have been moved to the other side of each other. In picture 3 the working ends have been tucked through the knot. Picture 4 shows the tightened knot. The knot shall be tightened so that the last bends of the working ends (that were made in picture 3) stay at the top of the knot.
Juho, this is a truly beautiful knot!

The big positives:
+ It is easy to tie.
+ It is beautifully symmetrical.
+ A four lobed structure is maintained at the base as well as the top.
+ It has a flat base.
+ The legs and working ends enter/exit straight through the centre.
+ Pulling on the working legs does not collapse the centre, but tugs on the edges, as Brion's Button does. I think the dynamics are good. It would of course need testing.
+ I think it would be super useful for thinner line than would benefit from a stopper that was easier to handle.

The minuses:
- Doubling would make it harder to tighten up. This may make less difference though if the legs are buried around for a length of around 30x, which previous load tests seem to indicate is needed for grip.
- The knot needs to be dressed carefully (a common issue).

Stu is our resident ABOK expert, so he may be able to tell you if it is unique. If it is we need to call this Juho's Button .

There are around 100 buttons described in the ABOK and I have not yet got around to tying any of them. I think though that if I needed to make an actual button, given its beauty and size and easy of tying, I would reach for this design.

Well done .

SWL
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Old 06-08-2017, 14:56   #68
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Re: How to tie a Diamond Knot

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Originally Posted by NevisDog View Post
So, which simpler construction knot do you use?
Well, the technically best solution (imho) is a rubber coated aluminum toggle. They are cheap & easy to make, 100% consistency, easy to engineer to (any) strength, and in my impact testing are no worse than a properly set (e.g. extremely hard) stopper.

Pure knot wise there are a few that are simplier. For example, the original high strength "overhand" is. But I have not really examined them in great detail because for the extreme application the toggle is so perfect.
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Old 06-08-2017, 16:05   #69
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Re: How to tie a Diamond Knot

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Originally Posted by Seaworthy Lass View Post
Juho, this is a truly beautiful knot!

The big positives:
+ It is easy to tie.
+ It is beautifully symmetrical.
+ A four lobed structure is maintained at the base as well as the top.
+ It has a flat base.
+ The legs and working ends enter/exit straight through the centre.
+ Pulling on the working legs does not collapse the centre, but tugs on the edges, as Brion's Button does. I think the dynamics are good. It would of course need testing.
+ I think it would be super useful for thinner line than would benefit from a stopper that was easier to handle.

The minuses:
- Doubling would make it harder to tighten up. This may make less difference though if the legs are buried around for a length of around 30x, which previous load tests seem to indicate is needed for grip.
- The knot needs to be dressed carefully (a common issue).

Stu is our resident ABOK expert, so he may be able to tell you if it is unique. If it is we need to call this Juho's Button .

There are around 100 buttons described in the ABOK and I have not yet got around to tying any of them. I think though that if I needed to make an actual button, given its beauty and size and easy of tying, I would reach for this design.

Well done .

SWL
I checked also the ABOK button knot pages (just skimming). At least the basic weaving pattern is present there. Knot #603 follows this basic pattern, but it differs in details, e.g. in the number of legs. Maybe there are others (or side notes) that are even closer or exactly the same.

With respect to the name, I think this knot is a very basic doubled button knot, so in case the knot doesn't already have a name, maybe it could be simply called the "doubled button knot". That would be a quite descriptive name since in addition to doubling there's nothing special in the knot (four lobes as usual, a very basic weaving pattern). And without doubling the knot doesn't really work well.
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Old 06-08-2017, 16:14   #70
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Re: How to tie a Diamond Knot

One more knot. This time a simpler and smaller one. Three sectors / lobes instead of the usual four.

Picture 1 starts from a simple overhand knot. Picture 2 adds a second loop. The first rope is now ready. The other rope will form a more or less similar pattern. It could simply follow the first rope (double the whole route), and that would give us a quite decent knot, but let's try to make the knot more balanced (not one-sided). In picture 3 the second rope starts to follow the first rope (above it) from another location (not from the root of the standing leg). In picture 4 the second rope still follows the first rope above it, but at the point where the working end leg of the first rope starts, the second rope starts to follow the incoming standing leg, and this time below it, not above. In picture 5 the second rope dives to the centre of the knot, next to the other working end leg. Picture 6 shows a tightened knot.

This knot could be useful in places where the knot need not be very big. Maybe for bigger ropes. The working ends stay at the top of the knot. Also this keeps the knot smaller. This button knot is maybe not as interesting as the previous one, but I wanted to study this kind of simpler and smaller knots too.
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Old 06-08-2017, 17:13   #71
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Re: How to tie a Diamond Knot

Just a note of caution about stoppers and bare dyneema . . . quite a number of the traditional stoppers will slip when loaded in bare dyneema (just for example the figure 8, the Ashley stopper knot and the triple fisherman stopper all slipped). I remember a dyneema 'expert' swore a 'specific special' one would never slip, but it did when tested. So, it is worth testing before going whole hog on a stopper design.
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Old 06-08-2017, 17:33   #72
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Re: How to tie a Diamond Knot

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Originally Posted by estarzinger View Post
I have tested a number of 'pro made' diamonds which were not sufficiently tensioned and the tails pulled into the knot, and untied the diamond, well before the shackle breaking strength.

I have never seen a button invert, even those tied by the exact same 'pros' as made the poorly tensionned diamonds above. The vast majority of the buttons I tested have had buried tails - so dont know as much about the behavior of non-buried buttons - but seems like if you are using a button you might as well bury.
Thank you, you have validated my suspicion.
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Old 07-08-2017, 01:23   #73
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Re: How to tie a Diamond Knot

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Originally Posted by estarzinger View Post
Just a note of caution about stoppers and bare dyneema . . . quite a number of the traditional stoppers will slip when loaded in bare dyneema (just for example the figure 8, the Ashley stopper knot and the triple fisherman stopper all slipped). I remember a dyneema 'expert' swore a 'specific special' one would never slip, but it did when tested. So, it is worth testing before going whole hog on a stopper design.
That's a valid warning, and certainly applies at least to the knot that I presented in post #70. I actually started my study of three lobed knots from the Ashley stopper knot. One reason why I ended up not using that construction was that there could be a risk of the centre loop (the first loop of the standing end) falling through the knot when tensioned. The post #70 knot could be even more prone to slipping than Ashley stopper based knots, who knows. Tests are needed to check how these knots perform with different materials.
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Old 07-08-2017, 07:03   #74
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Re: How to tie a Diamond Knot

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So I would certainly not agree that Brion's button is "anything but safe". Take a bit of care dressing it well and it is brilliant. Dress it poorly and it will fail like most other knots will.

SWL
you may be correct however button knot relies on dressing more than diamond knot (that only requires serious tightening) and chance of doing button knot wrong is larger.

Hence I will stick with diamond knot for critical SS. Thanks for instructions how to tie diamond.
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