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Shooted cast

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Merlin
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Re: Shooted cast

#21

Post by Merlin » Wed Sep 02, 2020 7:27 pm

I don’t think that release timing in relation to the haul is as important as release timing in relation to loop formation.
Fully agree Paul. Once max haul speed is achieved, dies are cast and nothing will influence line speed. Consequently one can focus on release time for the shoot. In Lasse’s video mentioned above, there is a time lag between what Lasse thinks he does and what he actually does, of about 60 ms IMHO.
“release at RSP”? I would say at MCF, 60 ms later.
Lasse video part 1.JPG
Lasse video part 1.JPG (36 KiB) Viewed 410 times
The line does not shoot immediately. There is a delay due (my interpretation) to acceleration of loop rotation speed, the loop widens since it has no other place to go at the rod leg level. The release is delayed by that acceleration directed at the back of the cast. If I want to simulate that I have to better define initial conditions: the acceleration at the rod leg level is not nil even if the rod leg speed is nil.

Release “before RSP”? I would say 20 ms after RSP, but before MCF and nearly just as the loop is shaped or slightly before.
Lasse video part 2.JPG
Lasse video part 2.JPG (32.45 KiB) Viewed 410 times
Conclusion: lag time (brain – hand) is about 60 ms or something like that.

Merlin
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Re: Shooted cast

#22

Post by Lasse Karlsson » Wed Sep 02, 2020 8:49 pm

Daniel, when the light comes on (red dot in the foreground on the two last pics) the line has been released. I have a contact in my hand... when you can actually see my hand opening, it happened before...

So not what I think, but what actually happens 🙂

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Re: Shooted cast

#23

Post by Mangrove Cuckoo » Thu Sep 03, 2020 2:49 am

So...

At the end of the haul...

Do you hang on the line until the line begins to shoot and it pulls out of your hand, or do you let go before that?

If you have just accelerated the line down through the guides shouldn't it continue on that path until some other force makes it change direction?

Could that be why the white marker appears to still be in (near) Lasse's hand when the light says he has let go?
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Re: Shooted cast

#24

Post by Paul Arden » Thu Sep 03, 2020 6:10 am

If you have just accelerated the line down through the guides shouldn't it continue on that path until some other force makes it change direction?
That’s why I was asking about tension in the loop during loop formation.

Let’s imagine the rod tip travelling from RSP to MCF under two scenarios. 1) running line. How much line if any can be shot in this period? Does the rod tip always pull the fly leg while the tip is slowing to MCF? Or is it possible to slip line from the ground to the bottom of the loop during this period? I know that I teach Down-and-Up for a distance haul because there is not very much shooting going on and “downup” often creates slack.

2 Shooting Line. Now in this case I think there is a difference. So that would lead to one possibility that the primary difference is ring/line friction. But I’m unsure and I would really like to understand how the Tension around the loop evolves from MCL-RSP2.

We also have to consider angular momentum. Maybe this is the real difference and not friction? Until the fly leg starts to overtake the rod I don’t see how this angular momentum can shoot line upwards. With a shooting head we don’t want the head turning in the loop and so it’s not such an issue because the loop is forming with mono. This is what you are saying and I agree!

What I do think however is that it’s also possible to shoot pre-RSP and I’m pretty sure this is the basis of the Snakehead Shot. That’s far earlier than the stills above. It works I know but I don’t see a difference down the tape with the MED for example, which is how I test these things. I’ve always been inclined to an empirical approach. :)

But let’s consider finally a shooting head being cast with overhang. I don’t see any difference - in theory - between releasing at RSP or MCF so long as the head stays out of the loop. But what I do think is that we don’t want to be holding that line when the head would otherwise come tight to the line hand.

There are a lot of unknowns in there for me!

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Re: Shooted cast

#25

Post by Lasse Karlsson » Thu Sep 03, 2020 7:38 am

Hi Paul

How can you get imperical evidence, when the only way to know for sure is to have a contraption strapped to you that shows what is happening?

This is what I wrote 9 years ago here:
Screenshot_20200902-230125_Chrome.jpg

I know I released early enough, when the fluff ends uo the furthest away from my feet, theres a ton of other things that need to be in order first, so its the last thing I mess with on the field, but after 20 years, the difference for me is lager than it is for you changing rods to something stiffer 😉

I hope Daniel grabs the right screenshots for his next post.

Cheers
Lasse

PS. This is what yiu wrote 9 years ago :D
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Re: Shooted cast

#26

Post by Paul Arden » Thu Sep 03, 2020 7:55 am

Christ we are still saying the same things after 9 years :D :D
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Re: Shooted cast

#27

Post by Lasse Karlsson » Thu Sep 03, 2020 8:30 am

Yup, you've been wrong for 9 plus years, thats some achivement, hats of 🤣
Btw, using Jim's contraption has hammered it in that we cannot see when the line is released since the fingers only have to come 0.035" or whatever thickness the line we're holding, appart for that to happen. And given the resolution of our camera's I can't see how any of us really can tell when the line is free to move.
This part still holds true 😉

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Re: Shooted cast

#28

Post by Paul Arden » Thu Sep 03, 2020 8:55 am

It’s not all or nothing either. Interestingly if you slow everything down, hauling while carrying a shorter line, you can feel the time when RSP occurs with the line hand. That’s how I knew we were hauling as the rod was unloading.

I don’t think these things are as critical as we might believe them to be. There seems to be quite a wide window available to get it “right”.

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Re: Shooted cast

#29

Post by Merlin » Thu Sep 03, 2020 9:03 am

So not what I think, but what actually happens

We may be right and wrong at the same time Lasse. I checked the video with the light as the reference this time. In the first case the light is on just after RSP (10 to 15 ms maybe if I can rely on the time scale). In the second case it is just in time with RSP. The second sequence is then not “release before RSP”, but a little bit earlier than in the first case.

In both cases the haul ends up at RSP or very close to it. In both cases max haul speed is in between MCL and RSP (excellent). Only in the first video the shoot is delayed by 60 ms if the scale time is correct. So there appear to be a loss in tension during a short period of time.

Merlin
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Re: Shooted cast

#30

Post by Merlin » Thu Sep 03, 2020 9:04 am

Does the rod tip always pull the fly leg while the tip is slowing to MCF?
I would really like to understand how the Tension around the loop evolves from MCL-RSP2.
We also have to consider angular momentum
The delay observed for the line to be shot in the first part of Lasse’s video suggests that there is a temporary loss in tension in that case. Is it because the release a slightly delayed after RSP or for another reason linked to the history of loop shaping? It is difficult to answer at this time.

If you analyze the angular momentum of the loop, then you establish the difference between the tensions at ends. This difference in tension depends on the variation of the rotational/tangential speed of the loop. If the loop decelerates in rotation then the tension at bottom is reduced and vice versa. Tension at the bottom can be higher that tension at the top of the loop sometimes (acceleration in rotation). The variation of tension around the loop is another complex story but when one can make some estimate (in “steady state” condition, neither acceleration nor deceleration) the middle of the loop can represent the lowest level of tension.

Merlin
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