Dissecting the haul

[Mangrove Cuckoo]

Folks,

At the end of 24 pages on another thread, Lasse posted something that gave me pause:

"When the haul peaks, the line is travelling faster than the bend tip, the tip is then free to straighten."

It doesn't give me pause because I disagree; it just made me realize that I had not considered that before. But, then I got to thinking about what exactly is a "haul"... or more precisely... when or how does the haul accelerate the line, and more specifically, when and how does the haul end?

I'm sure y'all can site chapter and verse on when the haul was first described, and how it was further refined to the famous "down and up", and whether that holds true today or not, how long or short it should be, etc...

But, there are some things that I don't think have been clarified. Or maybe it's just that I have not looked into it enough?

My curiosity is more about the "peak" term in Lasse's statement. Because that might take place somewhere in the middle of the haul, or at the end. And, what about what happens at the end?

The line may stay trapped in the hauling hand; or it might be somewhat controlled (like in feedback during slide); or it might be completely released.

It seems to me that where the peak (acceleration) lies, and how the hauling hand holds or releases, greatly affects how the haul contributes to the cast. And I don't believe I've come across any discussion on these finer details.

Would someone like to clarify my confusion?

[Graeme H]

Hi Gary,

I don't agree with the last part of Lasse's statement ("the tip is free to straighten"). I think he meant the rod is free to straighten, but even so, the rod should not begin to straighten until the force being exerted on the line through the rod begins to diminish. Accelerating line through a bent rod does not necessarily reduce the force the rod experiences. It's just adding acceleration to the line on top of the acceleration added by the rod.

If we stop rotating before the fastest haul speed is achieved, then the rod will begin to straighten because the total force being applied to the line is reducing. Generally, there are few problems in this cast.

If we stop hauling before we finish rotating, the rod will begin to straighten because the total force being applied to the line is reducing. This cast produces tailing loops.

As for the other parts of the question, we can examine casts more closely with this in mind with video analysis. I haven't done that, but there's likely to be some information in Gordy's files.

Cheers,
Graeme

[Bernd Ziesche]

Hi Gary,
I dont agree with Lasse on that either.
The max line speed of the line thru the guides may take place a little pre RSP1 for example. The rod starts straightening way before.
It doesnt matter how much we translate + rotate the rod. At some point in rotation the rod will start to straighten. Server Sadik said this 10 years ago and he was right.
I believe, that the haul has no impact on rod bend WHEN the rod already has some serious bend. The haul doesn't reach enough force. You can tie the rod into a fixed position, put some bend in and put some nylon to keep the bend fixed. You haul and the nylon doesnt provide slack. I tried that some years ago.
At some point the line speed keeps up with the driving speed (transl + rotation) and here the rod starts straightening, because its overloaded. That's what Grunde said and it makes sense to me.
I believe the tip then is so fast, that we cannot rotate faster anyway.
Regards
Bernd

[Paul Arden]

If we stop hauling before we finish rotating, the rod will begin to straighten because the total force being applied to the line is reducing. This cast produces tailing loops.

I used to think so too and it certainly can. However not if the rod angle is sufficiently past vertical at this point, eg on a stopless cast. Closely watching one of Lasse’s videos we could see that the point of loop formation translated back to the end of the haul and not RSP (the haul finished pre RSP on his 170 cast). The loop in question was a very nice V loop.

I think that’s what Lasse is talking about.

It has an interesting consequence on our common explanation of using RSP to separate fly and rod legs (casts and mends), because it is actually controlled in this case by the completion of the haul occurring pre RSP, and not by RSP.

Cheers, Paul

[Merlin]

If we stop rotating before the fastest haul speed is achieved, then the rod will begin to straighten because the total force being applied to the line is reducing. Generally, there are few problems in this cast.

If we stop hauling before we finish rotating, the rod will begin to straighten because the total force being applied to the line is reducing. This cast produces tailing loops.

These statements are correct but approximate; a better reference is peak haul velocity timing versus MAV timing.

At some point in rotation the rod will start to straighten. Server Sadik said this 10 years ago and he was right.

And so do I since 2010, the last time being here in post #43:
viewtopic.php?f=11&t=3990&start=40
If the rod is too fast for the cast, it straightens before MAV, if it is too slow it straightens after MAV, but this is a question of milliseconds (maximum 50), usually invisible to sight.

I believe, that the haul has no impact on rod bend WHEN the rod already has some serious bend. The haul doesn't reach enough force.

I would say it has little visible impact since the rod stiffness has largely increased due to its non linearity (hard spring).

Merlin

[Mangrove Cuckoo]

OK... thanks guys... but...

I think y'all went way over my head on the first step! (It's happened before in real life with quite comical results - but I digress).

Can we start with what a "haul" is?

Years back I compared and contrasted definitions in FFi and SL "speak". And while they may have changed in the interim, I don't see the word in either back then. Was that an oversight or a hint of uncertainty?

And, after that, can we simply state why it is used?

Baby steps?

[Lasse Karlsson]

For me a haul is pulling on the line in through the rings of the rod, mainly to accelerate the line further. Hauling starts when the line starts moving in through the rings, movement of the hauling hand can start much before.
For me hauling ends when the hauling hand is no longer accelerating the line, that can happen some time before the hauling hand stops movement in the hauls direction.

Rod starts bending at the butt, and through rotation that bend travels up the rod since the rod gets stiffer with the angle diminishing between rod and line.

Cheers
Lasse

[Paul Arden]

I would just say that hauling is pulling the line through the rod rings while the line is in the air. This also allows for the Check Haul.

Usually its purpose is to directly increase line speed. But it also has other functions and can be used to shorten line (eg strip haul). It can also remove slack.

Often the haul concludes around RSP. Which means that haul can continue through as the rod is unloading, theoretically both slowing the rod tip marginally, as well as potentially straightening tip path during this period.

Cheers, Paul

[Bernd Ziesche]

Rod starts bending at the butt, and through rotation that bend travels up the rod since the rod gets stiffer with the angle diminishing between rod and line.

Hi Lasse,
Your rod starts to bend at the stiff side?
Mine starts bending at the tip and the further I rotate, that bend moves further down into the stiffer end until my tip is too fast and the rod starts unbending no matter what I do. Pls. try to explain further.
I would agree, that for example thrust can help to position some bend into the tip section by compression effects.

Thanks Merlin, nice graphs!
Regards
Bernd

[Merlin]

Gary,

The haul has a direct effect and an indirect effect on line speed. The first one is straightforward, hauling the line through the guides increases line speed. The indirect effect comes from a law of physics and is related to the change in momentum of the line due to the variation in speed from the haul and to the reduction of mass of the rod leg occurring at the same time. A change of momentum (mass x speed) over time corresponds to a force which is applied at the tip top: the rod bends more and its unloading is delayed. This extra force generates more line speed as the rod unloads, but it is not in synch with the haul speed itself. If the timing of the haul is too soon (by comparison to MAV), the extra force can create a dip in the tip path, depending of the intensity of the haul (a mild haul may not induce a tail). If the timing is late (by comparison to MAV), there will be no tail whatever the intensity of the haul is. The best compromise is a haul for which the peak velocity occurs after and near to MAV, but if this peak is close to RSP, then the loss in speed is moderate (e.g. 5%) and the risk for a tail is nil. The bandwidth is small (e.g. 130 ms between MAV and RSP), so one needs training to fine tune the timing of one’s haul.

Merlin