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Covered topics /how it works

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gordonjudd
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Re: Covered topics /how it works

#101

Post by gordonjudd »

while the line is in flight the front slows down more than the back
As long as the fly leg is being pulled by the tension at the top of the loop and there are no transverse waves growing to produce loops in the line I think the speed of any point on the fly leg is the same.

Gordy
Bianchetti Ivan
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Re: Covered topics /how it works

#102

Post by Bianchetti Ivan »

gordonjudd wrote: Tue Aug 18, 2020 11:58 pm
while the line is in flight the front slows down more than the back
As long as the fly leg is being pulled by the tension at the top of the loop and there are no transverse waves growing to produce loops in the line I think the speed of any point on the fly leg is the same.

Gordy
In fact, I was referring to when the line is left before the loop is formed, Thanks for the always very interesting answer your discussion.
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gordonjudd
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Re: Covered topics /how it works

#103

Post by gordonjudd »

In fact, I was referring to when the line is left before the loop is formed,
I don't think I understand what you are seeing. Can you show a video that shows a case where the fly end of the line is traveling faster than the front of the line going from RSP0 to RSP1?

The trailing line is being pulled by the rod tip before the loop is formed. So once again as long as there are no transverse waves growing in that leg all the points on the fly leg should have the same velocity.

Gordy
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flyfisher666
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Re: Covered topics /how it works

#104

Post by flyfisher666 »

This tension, at the top of the loop, that is pulling the flyleg. How does it relate to loopsize? Does it increase or decrease with smaller loops?
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gordonjudd
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Re: Covered topics /how it works

#105

Post by gordonjudd »

This tension, at the top of the loop, that is pulling the flyleg. How does it relate to loopsize? Does it increase or decrease with smaller loops?
Joakim,
As has been pointed out before, for a distributed mass (unlike a point mass) the tension is independent of the loop size.
Gordy
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Paul Arden
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Re: Covered topics /how it works

#106

Post by Paul Arden »

flyfisher666 wrote: Mon Aug 17, 2020 6:03 pm Q: How does a loop morph?
A: From big to smaller.

Q: Why does a loop morph?
A: As the loop propagates away from you the tension force acting on the rod leg part of the loop gets more parallell with the fly leg and therefor "pull" the loop tighter.
This will become an interesting topic in itself, Joakim. I suspect there are a number of reasons. I would expect the overriding one to be aerodynamics.

Quite frankly I don’t think we really know. I’ve actually put some questions in there for that reason!

Right. I will structure these questions into a logical sequence. I tend to break flycasting up into Distance/Accuracy/Speys/Presentation. That won’t work for this of course. Maybe something like: Loop formation, Loop propagation, Post loop formation manipulation. Ok I’ll sleep on the last one. :p

Cheers, Paul
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Paul Arden
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Re: Covered topics /how it works

#107

Post by Paul Arden »

Mends!
It's an exploration; bring a flyrod.

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James9118
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Re: Covered topics /how it works

#108

Post by James9118 »

Paul Arden wrote: Wed Aug 19, 2020 5:50 pm I suspect there are a number of reasons. I would expect the overriding one to be aerodynamics.
Hi Paul,

If we look at the case where we see the most extreme loop morph - the '170' backcast, then I very much doubt the overriding reason is aerodynamic. If we all take time to study the well known film of Anna Hedman in competition - we can observe that the rod leg is placed on the ground during the cast, here it obviously has zero velocity and therefore zero interaction with moving air (unless there's a hurricane blowing, which there clearly isn't). Yet the line then suddenly jumps up into the air.

As such, I'd say the overiding reason behind loop morph is fly-leg momentum pulling the rod-leg taut.

Aerodynamics will obviously have a big effect also.

Cheers, James
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Paul Arden
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Re: Covered topics /how it works

#109

Post by Paul Arden »

Thanks James. Precisely why I’ve started this set of topics.
I'd say the overiding reason behind loop morph is fly-leg momentum pulling the rod-leg taut.

I can see I’m going to be piggy in the middle here. I have no problems with that.

Great to see you back mate.

Cheers, Paul
It's an exploration; bring a flyrod.

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Lasse Karlsson
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Re: Covered topics /how it works

#110

Post by Lasse Karlsson »

Loops also morph the other way, ie. from small to big... just throwing that into the mix here 😉

And that has to do with line velocity and where the flyleg is coming from.

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Lasse
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