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Alejandro wrote:In any case the assumption that a slower stop has advantages in the fly casting seems is not met in the reality.

Hi everyone,
I use a slow stop, when I want to shape an open loop and cast in relatively low line speed. That's when the soft stop seems to have it's advantage.

In regard of the WC in Norway I did not see any caster using a soft stop. They all had incredible high deceleration rates for their butt section. Those who used an arc of 160° as well as those who used an arc of 130°. No one was aiming for a low rate of deceleration. I think that was simply for one reason:

The lower your rate of deceleration will be, the less effective you can use your overall arc to produce max line speed.
In summary the smaller arcs usually result in tighter loops. Tight loops are good to have for distance.
Now some use a wider arc than others in order to achieve higher line speed. But still those using the wider arc don't waste any arc by slowing down the rate of deceleration imo.

I would be very impressed, if someone would throw far when using a low rate of deceleration for the butt section of the rod. And then we have to define what exactly are we talking about as a slow stop? Does it only refer to the deceleration of angular velocity, or does it include translational movement, too?
Those using a huge arc mostly run out of arm very abrupt at the end of their stroke. I understand this to be part of a very abrupt stop.
I doubt we will ever see any distance caster using a wide arc slowing down translational movement of the rod hand in a low rate.

I believe in distance casting everything happens fast.
Greets
Bernd

Since it appears that most distance casters, at least the very good ones, let go of the line before the rod has hit RSP1, does the stop really matter?

Cheers
Lasse

Hi Lasse,
yes it does. Cause, if you stop slow you have not used your arc and stroke very effective in my opinion and then it does not matter when you let go.

I'd like to see a video of achieving highest angular rotation and then highest line speed while slowing down rotation in a low rate of deceleration. I don't think that is possible.
Greets
Bernd

Lasse - do they release before they stop the rod butt?

Walter wrote:Alejandro,
What Grunde showed is that in the 170 cast I can apply force to the line for an even greater distance and get even greater line speed than if I had stopped the rod earlier."

I basically agree with you, and the most times I agree with Gordy and Merlin. What disturbs me a bit is the obsession to draw general conclusions and apply them to fly casting, based on simplified models that, in some cases, show the opposite result that occur in a real fly cast.

Claiming that a slow stop increases the rod tip work on the line does not match what happens in a real fly cast, and therefore I consider it false. You can discuss the reasons why that happens, but what we can not do is change reality to conform to any model.

What a cast 170 shows us is that greater momentum on the rod can result in increased momentum on the line in the direction of the cast, although some of that momentum is made in another direction. This I have defended in casting Spanish forums before Grunde will display it. Now, I think, most of us agree on the possibility of this happening ... which does not mean that always happens: if you do not know how to perform a 170 cast you will achieve better results with a narrower arc.

But this has nothing to do with a slow stop. In fact making small adjustments Grunde´s model we can see that with a fast stop we apply more force on the line for the same distance.
Is another possibility.

Torsten wrote: The general definition of the work is W = curve integral ( F(s) ds )

Hi Torsten
I have set a formula that allows us to calculate the work done by a force, you have written a formula that allows us to calculate the work done by a number of forces. Neither formulation or mine are a work definition. Usually the work caused by a force in a particle is defined as the change in kinetic energy in the particle, but if we think that energy is defined as the capacity to produce work found that work-energy definition form a dead end and therefore, since the object defined should not be part of the definition, we do not have a valid and logical definition for any of the two words. Fortunately this has no importance for us.

Merlin wrote: Where have anyone seen that a slow stop is better than a sharper one? It all depends on which ground you make the comparison. How does a 170 cast compares with a 100 one? It is a question of both maximum rotation speed and timing.

I have been using the 170 style just two or three years. I believe that I have not cast more than 10000 cast 170 style this time. Not much, but so far never seen a stop slower allowing me cast farther. All I've seen is that the result apparently is very similar in slow stop or fast stop.

Merlin wrote: I use a slow stop, when I want to shape an open loop and cast in relatively low line speed. That's when the soft stop seems to have it's advantage.

Yes, I agree.

Cheers
Alejandro

Alejandro wrote:Claiming that a slow stop increases the rod tip work on the line does not match what happens in a real fly cast, and therefore I consider it false. You can discuss the reasons why that happens, but what we can not do is change reality to conform to any model.

Well, it does increase the work. It is very simple physics. But, and that's a big but - only if the acceleration until that has been the same on both cases. Thus the tip travel on the lower deceleration (slow stop) is longer.
So, for a limited tip path length (like in distance casting), one wants to use as much as possible of that of acceleration -> fast deceleration (fast stop).

sms wrote:Well, it does increase the work. It is very simple physics. But, and that's a big but - only if the acceleration until that has been the same on both cases. Thus the tip travel on the lower deceleration (slow stop) is longer.
So, for a limited tip path length (like in distance casting), one wants to use as much as possible of that of acceleration -> fast deceleration (fast stop).

Hi Sakari,
I agree 100%.
This leads me to a simply question:
Can you achieve high tip speed when you slow down the butt section (of the rod) in a low rate of deceleration in real fly casting?
To me the answer is: NO. Even if I try that pantomimical, I can't simiulate it.
As soon as I accelerate my rod hand up to a high speed my body stops it in a high rate of deceleration at the end (no matter what my head wants it to do).
Does that make any sense to you?
Greets
Bernd

Well, it does increase the work. It is very simple physics. But, and that's a big but - only if the acceleration until that has been the same on both cases. Thus the tip travel on the lower deceleration (slow stop) is longer.
So, for a limited tip path length (like in distance casting), one wants to use as much as possible of that of acceleration -> fast deceleration (fast stop).

Sakari,
That is how I think about it as well. We only have a limited amount of rotation to use in making a cast and you want to make optimum use of the way you apply torque over that angle to apply the maximum amount of work to the line.

That is why good distance caster use late rotation with very high rates of exponentially increasing acceleration followed by high deceleration rates to make optimum use of that limited rotation angle range. You can see the CA measurements of Paul's distance cast showed that he reach very high rates of angular acceleration in that distance cast, but the deceleration rate was even faster.

In any case the assumption that a slower stop has advantages in the fly casting seems is not met in the reality.

Alejandro,
If I gave you the impression that I was saying a slow stop would always produce more line speed than a fast stop then no wonder you were having trouble accepting what I was saying about the force over distance work principle.

I think most good casters have very fast stops since that helps produce tighter loops in normal fishing casts. A faster stop means you have more angle available for the power application phase of the cast, so it would be an especially important requirement in distance casting.

But I do think that using the force applied over distance work principle is a very good way to understand how line speed is developed in casting, and when you apply it, you soon find out that the PE in the rod does not have anything to do with that calculation. I hope the "big spring" theory will some day be buried in the parking lot, but I think that day will be a long time coming.

Gordy

Gordy

I understood your comments the same way as Alejandro, it was why I asked for your definition. For me the force over distance principle ignores the effect of time, perhaps approaching it from considering the impulsive force to understand the change in momentum would be easier.

Vince

As soon as I accelerate my rod hand up to a high speed my body stops it in a high rate of deceleration at the end (no matter what my head wants it to do).

Bernd,
I think most good casters have put a lot of practice into learning how to make fast stops, and cannot just turn it on or turn it off.

By the same token the wrist is not as stiff as lashing the butt of the rod to a post, so I would think the amount of distance you get with a hand held bow and arrow cast where the caster intentionally rotated the butt forward after the line was released would go further than if the butt of the rod was clamped.

Gordy