## Double Haul timing

### Double Haul timing

VGB wrote:
James9118 wrote:Angular momentum.

You might need a bigger font.

I missed the mention to angular momentum in the video.
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Paul Arden

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### Double Haul timing

Starting at angular momentum is like trying to understand how a bike works by only looking at the cogwheel. There’s no point considering angular momentum until this is fixed in your mind:

grunde wrote:2) From loop formation and onwards the "driver of the cast" is the momentum
in the fly leg, this _is_ where the energy in the cast is.

Take Gordys falling chain and set gravity to zero. This is far closer to a fly cast because it removes the external force pulling the fly leg. If you do this nothing happens, there’s no tension and no cast.
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### Double Haul timing

Hi Gordy,

thanks for the picture! (I can't answer, your mailserver seems to block me)

> Here is Ulrik's (and Grunde's) study.

Thanks Daniel. Quite interesting, sure it's an inital study and only 4 caster included, but good reference values. What's missing is of course (as stated) a comparision with "bad haulers". Also it doesn't answer why the particular sequence is an advantage. I think there is still some further research needed.

Maybe it makes sense to separate this discussion into practical instructions and theory (and put theory in "Technical Analysis").

--

Just to be a bit more exact:
> "driver of the cast" is the momentum in the fly leg

The line itself is a particle system, the motion of the particles is constrained because some particles are connected,
every particle has usually a momentum. In distance you want to maximize the total momentum to a certain direction,
kinetic energy being constant that means all particles have the same direction to the target (for maximum efficiency).
Depending on the conditions the target might be more or less elevated.
In the real world you have deviations from this ideal; also you need the loop to unroll. This means at a certain point
tension on the bottom leg of the loop, else it's not unrolling well.

Thanks,
Torsten
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### Double Haul timing

Hi Vince,

I find that the cogwheel on bikes to be rather important.

In the case of the free fall loop why does it accelerate faster than the untethered chain?

Cheers, Paul
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Paul Arden

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### Double Haul timing

Am I right in saying that the tension we feel at the rod tip on an unshot cast is the same as the tension exerted on the fly leg? If so that’s not insignificant as we can see when shooting line.

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### Double Haul timing

Hi Torsten

Thanks for your input, I would volounteer to be a bad hauler in your study. I’m sure mine is at least 0.1 secs out There’s some very good video of a long cast with poor rod leg tension where the loop keeps collapsing and reforming that illustrates your point. I’ll post it if I get a chance.

Hi Paul

Try explaining how a bike moves by only talking about the cogwheel. If you find that too difficult, try explaining how a bike moves by starting from the cogwheel. The latter is possible but you won’t get a particularly coherent explanation. Both the bike and the cast are part of a system that is driven by external forces, I think it’s easier to explain things by starting at the point of input. A cogwheel is important but it’s not the complete system and you miss everything else by fixating on it.

I’m not sure what you are talking about with your free fall comparison is it a cast?

On an upshot overhead cast, you get tension during the stroke before loop formation, it drops off as the loop goes overhead and reassert sitself after loop formation. You can prove this to yourself by trapping the line against the rod butt with your finger and watching the line between your finger and stripping ring as you false cast. As the loop goes overhead, the line you are watching goes slack.

Regards

Vince
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### Double Haul timing

Ok here is one example:

youtu.be/X-QFAB0gEtE

Is the tension that we feel at the rod tip after the loop has formed, that we use for shooting line, the same as the force that is being applied to the fly leg?

Cheers, Paul
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Paul Arden

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### Double Haul timing

No Paul, in a fly cast gravity is acting at 90 degrees to the fly leg and not in line with it..

Torsten

This is the video I was referring to:

https://vimeo.com/76220542

Regards

Vince
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### Double Haul timing

How very interesting! So the loop accelerating the block only occurs in the direction of gravity. And the tension on the rod tip by the loop is not the same as the force exerted on the fly leg.

Cheers, Paul
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Paul Arden

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### Double Haul timing

Why are you very surprised by my answers Paul?
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