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Fly rod deflection

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Geenomad
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Fly rod deflection

#11

Post by Geenomad »

Merlin wrote:Here is the link to that second video

meadow cast

Merlin
I have to say that initially I was somewhere between skeptical and incredulous. :D Having watched the vid in the above link, my response is very different. Thanks for posting it Merlin.

Mechanics and vectors etc aside what I observe is a forward cast that ends with an slightly upward inflection of the rod hand. The stop then, is at the end of full arm rotation and extension (no further rotation is effectively possible) and the forward and upward thrust. This combination of movements seems to have the effect of preserving RSP. Body movement back and forward accentuates the nice translation. Nifty, biomechancially speaking. :)

Not so sure about an ideal transfer of kinetic energy but I do see some attractive economy of movement and that always gets my attention.

Will stay tuned with interest.

Cheers
Mark
"The line of beauty is the result of perfect economy." R. W. Emerson.
https://thecuriousflycaster.com
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Merlin
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Fly rod deflection

#12

Post by Merlin »

Thanks Mark

Some casters are able to control counterflex, and this is what I suspected here, but I am not able to analyse the casts as you can with this video. There is always behind the analogy with a whip: a whip would not counteflex but you would see a "wave" travelling along the shaft and shaping the loop in the line. The question is: can a beam (rod) bahave like a string (line)? There is a technical response to this problem which has been written by the Caltech University. This may happen sometimes in specific conditions, at the very limit. A typical example is casting a heavy line with a soft small rod (like Lasse casting a #12 line with a #3 rod), but even in that case there is a small counterflex. There are certainly several options to control the counterflex, one of them being the TLT style: a thrust at the end of the stroke generates an order to the rod like "you must bend backwards", which helps killing the counterflex. I wish I could be able to control the counterflex as some casters I have seen during fairs.

Merlin
Fly rods are like women, they won't play if they're maltreated
Charles Ritz, A Flyfisher's Life
Geenomad
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Fly rod deflection

#13

Post by Geenomad »

Thanks Merlin. That all makes sense to me - somewhat surprising as that is - to me at least :D

I like the whip analogy. In another life I used a stock whip quite a bit. I hasten to add it was on horseback and while mustering cattle. Hmm perhaps that only makes the hole deeper. :)

I will have a play with the technique. Have fooled around with TLT stuff before but never saw much in it for my sort of fishing.

Be interested to hear other people's takes on this.

I would just add that having the line extended behind a caster on the ground doesn't strike me as a great disadvantage in making a forward cast which is then miraculously overcome with moving centres of rotation and perfect transmission of kinetic energy.

Cheers
Mark
"The line of beauty is the result of perfect economy." R. W. Emerson.
https://thecuriousflycaster.com
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Merlin
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Fly rod deflection

#14

Post by Merlin »

I wrote an article on the whip effect, if some of you are interested, I can either send it directly (mail adress needed) or I can send it to Paul so that he put in somewhere on the forum.

Merlin
Fly rods are like women, they won't play if they're maltreated
Charles Ritz, A Flyfisher's Life
WJC
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Fly rod deflection

#15

Post by WJC »

...:a thrust at the end of the stroke generates an order to the rod like "you must bend backwards", which helps killing the counterflex.
It feels like on long forward casts, I am trying to time the late translation (thrust) , rotation, and haul to try to chase the unloading of the rod all the way to where I run out of arm. Since that thrust is generally fairly parallel to the fly line trajectory, and the final rotation is working against the unbending of the rod, would that not delay, or at least slow down tip deceleration ?

It seems like the biggest variable, when using the same rod and line, is the amount of line carried. Too much, and the MCL occurs too soon during rotation and I don't have the strength to continue acceleration; too little, and the shoot is too short.

It does not feel like there is a whole lot of counterflex this way, but I've not yet taken a video to check it out. Now that I have a camera capable of doing so, it will be interesting to see exactly what is happening.

Cheers,
Jim
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Merlin
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Fly rod deflection

#16

Post by Merlin »

Since that thrust is generally fairly parallel to the fly line trajectory, and the final rotation is working against the unbending of the rod, would that not delay, or at least slow down tip deceleration ?
JIm

The chance is not nil, but small, because the rod needs more time to load than to unload. As far as I remember the videos I saw on TLT casting, the thrust is quite late, but until now I have not tried to adpat my 2D casting model to a TLT cast and see what it tells. I guess a thrust is more adpated to the fast rods / light line combination used for TLT, but a thrust could also been adpated to the tackle, I have no experience with TLT casting, I should try some day, that may help me to control counterflex better.

Merlin
Fly rods are like women, they won't play if they're maltreated
Charles Ritz, A Flyfisher's Life
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gordonjudd
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Fly rod deflection

#17

Post by gordonjudd »

Some casters are able to control counterflex,
Merlin,
I wonder what the effect of counterflex might have on the loop propagation velocity?

If the counterflex is primarily minimized by relaxing the grip pressure as recommended by Carl Berlin, then it would seem that the counterflex is being reduced by the caster damping it somehow. However, that would imply a loss of flexural energy in the rod being absorbed by the caster, not an increase of energy going into the line.

You can see this video on Vimeo at https://vimeo.com/131846944 if it does not play here.

It would seem to me that the maximum line speed is established by the time the rod reaches RSP, and would not be effected very much (if at all) by what the rod tip does after that point.

I can see that the amount of counterflex will affect the initial loop size, but that initial loop size consideration is mitigated by what happens later on due to loop morph. When you look at the large initial loop size produced in the 170 distance casting style you would think that it would not propagate very far due to drag, but the loop soon morphs into a sexyloop that goes very far depending on the initial max line speed.

Thus I am wondering what reducing in counterflex actually buys you since most distance casters don't seem to worry about it.

Gordy
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Graeme H
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Fly rod deflection

#18

Post by Graeme H »

gordonjudd wrote:Thus I am wondering what reducing in counterflex actually buys you since most distance casters don't seem to worry about it.

Gordy
I've been wondering about this myself too. Is there some information around on the benefits of reducing counter-flex? I know there are aesthetic reasons, but practical reasons?

Cheers,
Graeme
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queenfish
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Fly rod deflection

#19

Post by queenfish »

I am glad I didn't read all these stuff before I took up fly fishing.
I would have never started.
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Lasse Karlsson
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Fly rod deflection

#20

Post by Lasse Karlsson »

Good for you Vince, and that adds to this thread in a positive learning way right?

Cheers
Lasse
Your friendly neighbourhood flyslinger

Got a Q++ at casting school, wearing shorts ;)
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