Realistic knot tests

[sashkello]

Hi All!

So, youtube is full of videos where people test knot strengths. And all of the ones I've watched so far fail to model a realistic fishing scenario. They all put knots under static weight until it breaks. That is not what happens in real life. You don't pull a fish hanging there like dead weight. Your knot goes under stress in short sharp periodic pulls, either due to fish fighting, or lure/bait casting. This works the knot over and might loosen it. I imagine some knots are more prone to this issue than others. 

Moreover, line thickness seem to play crucial role as well. Thick leader is much more likely to loosen than thin line which will break at attachment point way before the knot fails. 

Anyone approached this issue scientifically, with at least some sort of rigor? I'm still fine with using palomar or uni for vast majority of my fishing, but being of scientific background I'm curious whether someone has actually tried it. I'm kind of contemplating to do it myself if not.

Cheers,

Sasha

[james Cutler]

Youtube is amusement hour. It is the brother of fakebook.

[noelm]

I have done this (years ago) using very controlled conditions, tying various knots over and over, and almost all knots are OK when tied properly, the uni knot is consistently good for an easy to tie knot. Line quality has a big impact on knot strength, as does (naturally) lubricating the line when pulling the knot tight. The hook eye thickness compared to line thickness is important too.

Edited August 12 by noelm

[mrsswordfisherman]

3 minutes ago, james Cutler said:

Youtube is amusement hour. It is the brother of fakebook.

Beg to differ. I have used youtube to find how to videos of tons of things with great success. 

Facebook has its place too and if used properly is fine. 

Have a go @sashkello apply scientific rigor  

[sashkello]

15 minutes ago, mrsswordfisherman said:

Have a go @sashkello apply scientific rigor  

Challenge accepted! Will make it as a scout project with my kid, good opportunity to add another badge

[big Neil]

1 hour ago, sashkello said:

Challenge accepted! Will make it as a scout project with my kid, good opportunity to add another badge

Good onya Sashkello. I would be interested in how you go about it and also the results that you achieve. Good luck with your scientific testing.

bn

[XD351]

I stopped watching those types of videos because they end up being based on opinion rather than scientific fact . One test I always wanted to see was to test the  strength of a knot used to join a leader to braid after it has been through a set of rod guides a  hundred times . 
One factor which will be difficult to control is continuity in regards to the tying of each knot - could a minor difference in something like tension make a significant difference in knot strength - this would I suspect to be fairly important for knots like the FG. 
These days I just stick to what I know and what I’m comfortable with and let everyone else do their own thing .

[sashkello]

27 minutes ago, XD351 said:

One test I always wanted to see was to test the  strength of a knot used to join a leader to braid after it has been through a set of rod guides a  hundred times . 

Exactly my thoughts - leader knot should be resistant to rubbing and pulling, not static force. For this one, would need some kind of machine to run it over an obstacle multiple times, which would be a bit hard for an amateur tinkerer.

[noelm]

58 minutes ago, XD351 said:

I stopped watching those types of videos because they end up being based on opinion rather than scientific fact . One test I always wanted to see was to test the  strength of a knot used to join a leader to braid after it has been through a set of rod guides a  hundred times . 
One factor which will be difficult to control is continuity in regards to the tying of each knot - could a minor difference in something like tension make a significant difference in knot strength - this would I suspect to be fairly important for knots like the FG. 
These days I just stick to what I know and what I’m comfortable with and let everyone else do their own thing .

Which is why when I did my tests, I did multiple tests of the same knot, all tied by the same person. 

[slowjigger]

6 hours ago, sashkello said:

Exactly my thoughts - leader knot should be resistant to rubbing and pulling, not static force. For this one, would need some kind of machine to run it over an obstacle multiple times, which would be a bit hard for an amateur tinkerer.

It would be too hard to come up with a consistent way of testing. And if the conditions aren't repeatable then you won't get any useful information. That said I have had locked half blood knots unravel, always when fishing from a height. I have taken to leaving the tag end long and tying a couple of half hitches. Also with heavy mono I melt the tag end with a cigarette lighter (carefully) to create a mushroom shape. 

 

Edited August 13 by slowjigger

[Burger]

2 hours ago, slowjigger said:

I have taken to leaving the tag end long and tying a couple of half hitches.

I do this for my swivel, but not my hook. This is to further prevent float loss.

Mind you, I can’t remember when any of my mainline Improved Clinch Knots failed.
I do think they’ve failed a couple of time on my FC leader to hook, but not often enough to worry about.

[DerekD]

Hi @sashkello

Excellent topic but I'm going to take a slightly different tack to the one you proposed. I am splitting hairs but that is how good discussions develop.

When mentoring people I get annoyed when people test knots by snapping their hands apart rather than gradually loading them up. i point out that they are shock loading the knot and if you are fishing properly this doesn't happen in the real world like that. My argument is that while the line can load up very quickly it is not shock loading because the rod tip absorbs this and then line stretch to a lesser degree (one argument for fishing mono for species like marlin). Finally the drag system is there to help prevent excessive loading of the line.

So while I agree that the line tension can change rapidly during the fight it shouldn't be shock loading. These tests are great in the way they test the relative knot breaking strengths which makes it a benefit in helping you select a knot which suits your needs. I am not sure how you could test your hypothesis and if the data is even relevant because you are talking about scenarios assuming you are fishing at 99% of the systems weakest link.

The rubbing is another issue I need to think further about but I discourage any of the people I help from having the line knots running through the guides.

Regards,

Derek

[big Neil]

21 hours ago, sashkello said:

Challenge accepted! Will make it as a scout project with my kid, good opportunity to add another badge

Don't be discouraged from doing this project with your kid, the benefits to you both far outweigh the potential outcome of an inconclusive result. Even then, the potentially inconclusive result is subjective. It will be a series of results based on the set testing criteria...that, in itself, will be interesting. It will teach your kid how to question the how and the why, and ultimately be of benefit to them in later life.

Go for it, post your results, and people can form their own opinions.

Cheers, bn

[Little_Flatty]

8 minutes ago, big Neil said:

Don't be discouraged from doing this project with your kid, the benefits to you both far outweigh the potential outcome of an inconclusive result. Even then, the potentially inconclusive result is subjective. It will be a series of results based on the set testing criteria...that, in itself, will be interesting. It will teach your kid how to question the how and the why, and ultimately be of benefit to them in later life.

Go for it, post your results, and people can form their own opinions.

Cheers, bn

Agreed. Much that can be learned by measuring and testing things out. Often what we first thought is not always supported by real world evidence.

One thing I’ve read is that the number of turns used in a knot can make a big difference to its strength. Apparently, holding material and other factors equal, it tops out at a certain number of turns and then declines beyond that. I read that in a book written by a mulloway gun and fishing nerd Sol Bannura (great read if you can find it!). He actually toys a lot with things like that. Would be interested to see the results if you go down that testing route.

10 hours ago, DerekD said:

Hi @sashkello

Excellent topic but I'm going to take a slightly different tack to the one you proposed. I am splitting hairs but that is how good discussions develop.

When mentoring people I get annoyed when people test knots by snapping their hands apart rather than gradually loading them up. i point out that they are shock loading the knot and if you are fishing properly this doesn't happen in the real world like that. My argument is that while the line can load up very quickly it is not shock loading because the rod tip absorbs this and then line stretch to a lesser degree (one argument for fishing mono for species like marlin). Finally the drag system is there to help prevent excessive loading of the line.

So while I agree that the line tension can change rapidly during the fight it shouldn't be shock loading. These tests are great in the way they test the relative knot breaking strengths which makes it a benefit in helping you select a knot which suits your needs. I am not sure how you could test your hypothesis and if the data is even relevant because you are talking about scenarios assuming you are fishing at 99% of the systems weakest link.

The rubbing is another issue I need to think further about but I discourage any of the people I help from having the line knots running through the guides.

Regards,

Derek

Also agreed. You’d have to be fishing a broomstick in a solid rod holder, with straight through braid and have your bait or lure taken by a very savage fish to genuinely shock load your rod. As that is not a very effective or pleasant way to fish, that’s not a very realistic scenario.

This sounds very much like something that is up @Volitan’s alley!

[2sheds]

Hi all

There used to be a website 'Paulus Just Fishing' which had a swag of data on breaking strains of mono and braid lines for a multitude of brands.  Also recorded the breaking strains of various knots in mono and braid.  Tests were performed using industrial grade equipment using standardised and rigorous methodology. 

One of the main points from the website is you can't know how good your knots are unless you know the correct breaking strain of your line - and it isn't always close to what it says on the spool, especially with braid.

The website is now gone (disappeared about 2018) but can still be accessed using the way back machine using the link below: 

http://web.archive.org/web/20171123043625/http://www.paulusjustfishing.com:80/4linetesting.htm

It is well worth reading through the info on the site, it will change to way you approach braid and mono and knots you use.

Just as an aside, those little waterproof knot booklets put out by AFN are a good guide for knots, especially when you have already gleaned some accurate information from the paulus website.

Regards

Twosheds

Disclaimer:  I'm mainly a bottom basher looking for a feed and I don't use any more than 6 different knots, mainly cause I'm old and can't remember more than that.  I rarely have a knot failure, but when it happens it is invariably due to (a) I didn't tie it properly because I was rushing or sloppy, (b) the line was already damaged when I retied the knot because I was too lazy to cut out the damaged section as that would have entailed replacing the entire rig.

 

 

 

[sashkello]

10 hours ago, DerekD said:

When mentoring people I get annoyed when people test knots by snapping their hands apart rather than gradually loading them up. i point out that they are shock loading the knot and if you are fishing properly this doesn't happen in the real world like that. My argument is that while the line can load up very quickly it is not shock loading because the rod tip absorbs this and then line stretch to a lesser degree (one argument for fishing mono for species like marlin). Finally the drag system is there to help prevent excessive loading of the line.

 

These are exactly my thoughts - neither of such approaches (static pull vs shocks) will test a realistic scenario. I'm thinking about attaching a weight under a heavy rod and dropping it from a fixed height - rod will absorb shock naturally and will mimic casts or fighting fish well enough.

I have a strong feeling though that I won't be able to break well tightened knots easily at all... But yeah, I'll definitely try it either way. 

[sashkello]

2 minutes ago, 2sheds said:

when it happens it is invariably due to (a) I didn't tie it properly because I was rushing or sloppy, (b) the line was already damaged when I retied the knot because I was too lazy to cut out the damaged section as that would have entailed replacing the entire rig.

That is my experience as well. Proving that a well set knot will not fail until the line breaks would be a good result as well, even though not unexpected by many.

[big Neil]

4 hours ago, 2sheds said:

Hi all

There used to be a website 'Paulus Just Fishing' which had a swag of data on breaking strains of mono and braid lines for a multitude of brands.  Also recorded the breaking strains of various knots in mono and braid.  Tests were performed using industrial grade equipment using standardised and rigorous methodology. 

One of the main points from the website is you can't know how good your knots are unless you know the correct breaking strain of your line - and it isn't always close to what it says on the spool, especially with braid.

The website is now gone (disappeared about 2018) but can still be accessed using the way back machine using the link below: 

http://web.archive.org/web/20171123043625/http://www.paulusjustfishing.com:80/4linetesting.htm

It is well worth reading through the info on the site, it will change to way you approach braid and mono and knots you use.

Just as an aside, those little waterproof knot booklets put out by AFN are a good guide for knots, especially when you have already gleaned some accurate information from the paulus website.

Regards

Twosheds

Disclaimer:  I'm mainly a bottom basher looking for a feed and I don't use any more than 6 different knots, mainly cause I'm old and can't remember more than that.  I rarely have a knot failure, but when it happens it is invariably due to (a) I didn't tie it properly because I was rushing or sloppy, (b) the line was already damaged when I retied the knot because I was too lazy to cut out the damaged section as that would have entailed replacing the entire rig.

 

 

 

Just like you Twosheds (interesting name) I am always interested in scientific results, but also rely on my own judgement a lot and try to get the best outcome by tying knots that are appropriate and well assembled. Nice to hear from another old fart.

bn