New Knot ?

[gstours]

Ive got a question for all of you. (yall).     Here is a link to a person, Toit, who is making like he invented this new knot and some of its findings.  As many knots are a variation of others with a different twist,  Maybe it takes the best features of three knots and renames it ?   Anyway?

https://youtu.be/SWWK2Nsc8BU?si=myGQwrGKM_KT21h7

 Skip the first 2 min of intro,  butt then it gets interesting. 
     I would like to hear your comments,   

[Hardy Boy]

Does not seem any better than what we have already. I stay with my uni, reverse SD and polamor.

Todd

[jurelometer]

TLDR: His data show an inconsistent knot.  Consistency is one of the most important properties in a fishing knot.  Tag out the front is worse than he suggests.  Catches weed, the jaw on a hook set, and more likely to tangle on a slack line.
——————
Looking at the videos-

1.  The biggest problem that the graphs show (but I did not see him mention) was the high variability in breaking strength.  For example, on the 80 lb mono, his worst sample  looked to be less than 70 percent of the best sample.  And all of the graphs are pretty jagged.  And 70% is a useful but not remarkable knot.

The average is not the most useful number when sampling the point of catastrophic failure.  For example, let's say a climbing harness on average could safely hold a 250 lb human, but one out of ten harnesses would break and kill a 180 lb climber ...

While generally not fatal, losing  one out of ten big tuna from a knot failure ain't so great either. Especially considering the others that you have also lost to sharks, lines getting crossed, hooks bending, etc.


Strange that he went right by this.

2. Lots of tests breaking above his tested line strength.  His explanation was not very satisfactory.

3.  Looks like a trilene  knot with an improved albright style wrap.  I would have called it an improved trilene knot, or reverse trilene. 

Tag sticking forward is no bueño for a terminal knot for the reasons mentioned in the TLDR.  And it looks to be bit fat.

4.  Probably better to soak the line samples and knots before testing, especially with nylon.   The line and knot are going to be used underwater.

Doesn't seem like a terrible knot, just not special enough to replace any of the knots in the limited space in my brain used to store knot tying.

-J

[alantani]

watched about 15 seconds of the video and had to turn it off. 

[Crab Pot]

I agree with #3 J.

Double loop through the version.

[boon]

I always try to keep an open mind about "new" knots. There is quite a bit of "No thank you, I'll just stick to my favorite double granny knot with a twist" attitude amongst fishermen.

It's rare that any new knot comes with such a breadth of test data, regardless of the outcome or misgivings about methodology, so I will certainly give them that.

Tag out the front is a virtual non-issue IMO. Every crimp has functionally the same effect to some degree and they catch plenty of fish.

[jurelometer]

Tag out the front is a virtual non-issue IMO. Every crimp has functionally the same effect to some degree and they catch plenty of fish.

Respectfully disagree. Crimps in mono can and should be trimmed pretty close to flush.  This is very different from a tag sticking forward. 

But to your point, there are some situations where the tag direction won't matter, for example tied to a jig with a big treble hook.  It won't tangle,snag or catch much more weed.

But tie it to a standalone swivel, a fly, a circle hook (especially with a large diameter stiff leader and a light wire hook), a forward tag will absolutely be a disadvantage.

I lurve me some science more than just about anyone here, but just because the guy gets a bit sciency, it does not validate his claims.  His own data suggests a knot that has highly variable strength, which puts it in the realm of meh...  BTW, he was able to get consistent knot strength on his bimini tests, so he is having issues tying his own knot here. He just focus on the average strength - which is just plain bad engineering. 

But I also agree with your basic premise.  People are uninterested in investing in something that might be better when they have something in hand that is good enough.  Especially fishermen and knots.
Can't blame them. 

-J

[jurelometer]

Hope this is not veering too far of topic:

In most cases we worry too much about absolute strength,  but the other knot features are often more important, and quite often we want the knot to be the point of failure so that we are not leaving a bunch of line in the water. Or the strength does not matter much on a terminal knot tied to a stronger leader.

Things that matter in a knot in no particular order:

- fast to tie
- easy to remember
- tightens easily
- consistent and reasonable breaking strength
- small profile
- doesn't use up a bunch of leader
- can be tied without looking at it
- tag pointing back, or at least not the standing direction
- doesn't require tools, adhesives, or a lighter
- works on a variety of diameters,hardness, types of line

A clinch knot actually does pretty well except for the last category.  Maybe that is why it is the most popular knot out there.

Average breaking strength does not make my list. I find it to be somewhere between of limited value and useless.

-J

[gstours]

Thanks for your comments.    Because of your earlier contributions to this site there was suspicion in my mind. Here is how he ties the knot.
https://youtu.be/sNfdCQy1Lxo?si=unVWvZsYBQtBJPAw

  While I have used my spring scale and ratchet constant testing device it seems at first that this knot is about equal to the Uni and the Sandiago in breaking strength on braid.  Braid should have been mentioned in the first post as this is where my interest is.

  Another knot question ive had is knot lube in testing and its final application in the water when fishing.
https://youtu.be/4WBW67gQx0E?si=b_qVMBk9hk9M-DaK

Many of us are trying to learn here and this site is very good for that.   Thanks.

[jurelometer]

Sorry Gary,

Like Alan, I have a hard time making it through this guy's videos.  Something about his presentation style.  So I can't comment in too much detail. 

But a few points.

1.  When you want to project  the results of a small set of data to an expected outcome in the world at large, you care about the mean (AKA average) and the standard deviation.  The standard deviation is  a number that describes the how far off the average the samples tend to be.  Sometimes the deviation is important in its own right as we were discussing earlier. But it can also be used to verify the reliability of the average score.  If you have a small number of samples and a large standard deviation, your average is not very reliable. 

In this case it is pretty easy to tell.  Remove one test result at random out of each test group and recalculate the average.  The results  will change, often dramatically. try again selecting the greatest outlier.  Even worse.  You don't have to even do the math, just look at his charts.

I zoomed through the video, but all of  the charts I saw were small sample size and very jagged, so the comparisons are pretty useless.  If one lubricant averaged 20% and another 80%, then maybe something useful.  But they are all pretty close in the 70 to 80% range, so pretty useless.  Also got different results from salt vs freshwater ( - probably dried one more than the other)

2. He is also wrong about why fishing knots fail, why he is getting knot breaking strength samples greater than line breaking strength samples (probably), doesn't seem to understand the importance of wet vs dry line, the effect of elastic vs permanent deformation on knot testing, the importance  of how the strain is applied on the test results, etc.

Don't want to be too harsh on the guy.  But I find enough known inaccurate claims that I find it hard to take much from the rest of it. Maybe he is a simply motivated guy with a strain tester, and not a subject matter expert?

But it did inspire me to check up on the science of knots from folks actually being more faithful to the scientic method.  Here is one that I am reading now that is using fluoro  fishing line.  Mono knots fail at the point where the line becomes deformed and loses cross sectional thickness (NOT  ABRASION). Cross section shapes are discussed (J vs I,etc.) and the type of junctions involved.  I know that most folk here are  not likely  to read a scientific paper, but it is helpful to see what useful testing and analysis looks like.
https://iopscience.iop.org/article/10.1088/1367-2630/9/3/065/pdf

Thanks for bringing this topic up!
-J

[jurelometer]

On the question regarding lubricants. Lubricants allow you to tighten the knot with less force, which will deform the line less when tightening, especially at points where it is going to eventually fail. It will also help (or at least not hurt) distributing the load as the knot is tightened, so you are not unnecessarily deforming the line at a single point when tightening.

As to what to lubricate with:  from a strictly logic based perspective:  water won't hurt, as it is going to get wet when you fish it anyways.  Saliva is 99% water and some other stuff that will wash off when the knot gets wet.  Nylon can be affected by some chemicals (esp. solvents), fluoro fewer (I think) and PE braid hardly any.  So I would rule out messing with chemicals to keep things simple.  Also, depending on the knot, you may not want the extra slippage after initial tightening, so that rules out anything that is not water soluble, like chapstick. 

At least that is how I see it.   But I don't have a strain tester and a YouTube channel, so what do I know?

-J

[JasonGotaProblem]

I look at things very simply when evaluating a new knot. Namely, I test it. I pull on it til it fails. If it broke at some random spot on the line, it's worth considering as a keeper. If it broke at or very near the knot, ...well I already have knots that dont do that.

[gstours]

Thanks for your comments.    Knowing this would be a controversial topic and suggests i was fishing for some answers, my caution was thrown to the wind.   Its been penned,  Knowledge and experience can be powerful tools for achieving eventual success in an endeavor...
 The physics of mono fishing line is studied and brought out two more questions.


4.Conclusions
When the torus series of knots were made in a PVDF monofilament, the tensile strength gradually decreased with increasing crossing number. The two reasons for this phenomenon were squeezing and rotation of the filament.
At lower crossing numbers, the knot was significantly squeezed due to the lower rotation of the filament.
Therefore, breaking occurred at the shoulder position within the knot, where the highest bending was obtained.
When the crossing number was increased, the enhanced filament rotation induced torsion within the knot, resulting in breaking at one of the entrances of the knot before squeezing into the entire knot.
These effects of filament squeezing and rotation led to a breaking-position shift from inside to outside the knot with increasing crossing number.
These results suggest that both squeezing and rotation, which are characteristic for a given knot, dominate the breaking position of the knotted strands.


In contrast, Pieranski et al reported that the strength of torus knots increases with increasing crossing number for a nylon monofilament.
This means that the material used is one of the predominant factors to determine knot breaking behaviour.
This discrepancy between our PVDF monofilament and their nylon one might be also attributed to the above-mentioned balance of different deformation modes.
The higher resistance for torsion and/or ease of bending could decrease the breaking strength of the knot with the lower crossing number. However, further work is required to evaluate the true effect of the filament material used.
We expect that theoretical analysis is another approach to understanding the knot breaking mechanism.

Does the statements above imply that Braid, Floro, might also react in a different way as each material has a resistant effect on heat, bending and elongation?

  And lastly did I read the technical wording and graph correctly as they mention that as each, oor after 3-4 turns the knot becomes weaker with each turn slightly until 9 turns then it levels off ?  gst?
 
 

[jurelometer]

Absolutely.

1.  There are different categories of strength measurements.  There is elasticity which tells you how much a material can stretch without permanently deforming.  And there is compression strength which is resistance to being squeezed, and tensile strength, impact strength, and so on.

2. Within each strength category, there is a range of specific tests, with some being more relevant to the material being tested  and/or the situation it is being tested for. 

For testing fishing knots, we want specific tensile strength tests:  I would argue that we want a sudden slack to load breaking strength test at something like ten MPH, and more importantly. a  steady endurance test, something like finding the maximum load that this knot handle for twenty minutes. And it should be with soaked line, as nylon mechanical properties change significantly when it has absorbed lots of water.

The funny part of all this is that we don't need a fancy machine.  Just do the jerk-with a-scale test that we all do, plus maybe hang a bucket from a rafter for half an hour. we would have a much better information.  I would argue that we don't need the exact point of breakage on the endurance test, just an appropriate success number (e.g. 80% of true breaking strength for a terminal knot not tied to the mainline).

Those machine based, single steady pull-to-failure tests, while repeatable and convenient, are not as useful.  These tests favor knots that slip a little before fully seating, like the knot that started this discussion. We care about how strong the knot is over the course of the fight, not just the very start.

3. The materials themselves have specific properties, and some like gelspun polyethylene fibers in PE braid have different strength properties along vs. across the line.

Typical Nylon fishing line is closer to a basic unmolested thermoplastic, where  there is not much directional difference.  Not sure about fluoro (PVDF), but I assume it is the same or at least similar in this regard.

PE braid fibers are very different. Ordinary (semi-crystalline?) high density PE has been transformed into long chain macromolecules (basically long skinny molecules) that have snaked together.  With the molecular bonds running more along a single axis, we  get very good tensile strength along the fiber, but very poor compressive strength and high brittleness across the fiber. No free lunch in science.  Add in the very low coefficient of friction (more slippery), and you can see why braid is a challenging material for knots.

Also, any type of multi-fiber line/rope makes it trickier to predict strength or get repeatable results, as we have to deal with the interaction between the fibers in addition to the overall knot itself.

-J

[jurelometer]

On the specifics of the number of turns, not sure that I can take a 100% confident position.  I got distracted on some cool new (to me) papers on fish vision - "look - a science squirrel" .  I have to go back and read this paper more closely.  I think that these findings are only accurate for the knot tested, but does give us some guidance on what to expect, especially for knots with similar form.

Didn't mention in the previous post, but hardness is a material property that should make a difference.  The hardness should affect the deformation shapes and load distribution.  Fluoro is usually harder and less elastic the nylon, which might be the source of the different scores.

We keep hearing that a knot is held together by friction, but it is not simple sliding friction.  Especially with mono, where the cross section shape is a big part of the picture.   

If you think about it, a knot's main job is to keep the tag from pulling out.  In mono, if you pull the standing end around a bend, it will have to change direction.  This starts the deformation of the line as it is being stretched, which is good because the line has to be continually deformed to pass through farther, which provides resistance to the tag pulling through, but bad because you are weakening the line by deforming it. The same twisting, thinning and cross section shape change that provides resistance is compromising the tensile strength.

A knot is a balancing act between holding the tag and weakening the line.  Knot strategy is about using a set of wraps and bends to distribute the deformation over more spots while still creating enough resistance to hold the tag.  And at some point there is no load left to distribute to additional wraps.  Most common knots are best from zero to less than half a dozen wraps, but something with less aggressive bends and wraps like a bimini can spread the load over thirty or so wraps in mono.

Or something like that...  I am just a science fanboy not a trained knotologist- or whatever they are called.

-J