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Walter & Group...
[GH] For our new members: RSP = Rod Straight Position.
From yesterday's message :
[GH] From Paul Arden:
"If the haul finishes pre-RSP it's possible for the loop to form then...... "
Paul...
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[GH] Paul...
Right !
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[GH] Aitor Coteron's message give me some second thoughts about my reply :
Hi Gordy,
This is what Paul Arden has recently written:
"If the haul finishes pre-RSP it's possible for the loop to form then...
Basically I consider the point of loop formation to be the instant the fly leg turns to rod leg, but picking that is hard without video footage of the loop at some point later in the cast as it's unrolling - then you can travel back in time to find out when it happened."
Well, I'd love to see that kind of behavior. Take a look at this high speed video to see a haul that finishes before RSP and, however the loop forms after RSP:
Password: Gordy
Any comment?
Thanks,
Aitor
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[GH] Aitor....
At first I wondered if Paul was referring to the line wave leading to a tail which forms when the haul is made and finished before RSP as some evidence of early "loop formation"..... but if that were true, he contradicts that idea when he says, ".......I consider the point of loop formation to the instant the fly leg turns to rod leg................."
At the Atlanta Fly Fishing School, we tried many combinations of casts and hauls and on video never identified the start of loop formation except close to RSP. We just didn't have a camera with sufficient FPS to prove that loop formation occurred at any time other than at RSP.
Your video is much better than the ones we attempted ......
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[GH] From John Symonds :
Hi Gordy,
Please correct me if I am wrong but........
The stop occurs at the end of rod-tip acceleration because after this point the fly-line is traveling faster than the rod-tip and so no more energy can be transferred to the fly-line, if hauling is discounted.
The stop also occurs at maximum rod-flex because up to this point the rod-tip is always accelerating and hence loading the fly-rod.
The point of maximum rod-tip velocity is some very short time after the stop as defined above because the continuing rotation of the rod-tip, caused by the kinetic mass of rod line, has a greater influence on rod-tip velocity than the unflexing of the fly-rod.
Hauling occurs independent of the stop and can be applied to add to rod-tip velocity at any point in the casting-stroke but the most efficient time will be when it coincides with the peak velocity caused by rotation.
Best regards - John
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[GH] John,
In general, I agree with what you have written. Some questions come to mind :
1.) I wonder if the stop sequence actually begins at the point of maximum rod load .... or at maximum rod bend. (As you know, it has been argued that the point of max. rod bend may not actually be the point of max load.) ?
2.) Scratching my head as I nit pick your last statement:
You state, " .......the most efficient time will be when it coincides with the peak velocity caused by rotation."
Peak velocity of the rod tip has been shown to occur during approximately one tenth of a second prior to RSP as the rod is decelerated (part of the stop sequence). That suggests to me that the peak acceleration of the haul might be most efficient when it coincides with the peak acceleration of the rod. This would fit well with your third paragraph
That would also be in keeping with the ever more popular "mirror image" concept of matching the haul to the casting stroke. Intuitively, I think of an efficient haul for a long cast as matching the casting stroke in terms of length, power application, and timing. Having said that, I don't know if this has ever actually been proven.
Steve Rajeff has called attention to another factor .... that is when the haul is stopped during false casting and when the haul line hand release occurs on the delivery cast.
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