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[GH] Before closing out this topic, we have a few more comments to share . One fine day, I'll launch the topic of "Testing techniques."
From Mark Milkovitch :
Gordy,
If I may, the question itself is interesting and subtle: Explain and demonstrate the casting stroke as it relates to changes in distance. I don’t believe the mantra “long casts, long strokes” is necessarily an accurate or acceptable answer. The problem comes in because there is no one definition of stroke. While it is frequently defined as hand travel, Mel Krieger defines the stroke as the arc (“Flycasting requires casting strokes (arcs) of all sizes.” (Krieger., 1987, p.9). If “stroke” can reasonably be taken to mean hand travel independent of rotation, then there need not be any relationship between casting stroke and changes in distance. As your experiments showed, longer translations are not an adequate adjustment for longer casts. The modification most directly linked to changes in distance is a change in arc and even that is subject to differences in power application. For me to be sure the candidate understands, I would have to ask the follow up question: In addition to stroke length, are there other adjustments to the casting stroke you would suggest to students as casting distance changes? Even then, if the candidate doesn’t key in to the arc difference I might draw a picture like the one at the top of Krieger pg.6 showing the rod start & stop positions with a space between to illustrate hand travel and say: this drawing shows three elements: rod start position, rod stop position with a space between the two to illustrate hand travel. Which elements would change for a longer cast and how?
Mark
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[GH] Mark,
Of course these things do depend upon definitions of STROKE and ARC.
It is my opinion that for most casters the concept of "long stroke and wide "arc" for a long cast..." pertains since it is in keeping with my own way of viewing the casting stroke and casting arc.
There are exceptions. This is far from the end of the story .... a gross simplification which works for teaching.
Although not in Mel's book, I recall him demonstrating, years later, what he called his "VARIABLE ARC ". This was the angle between the rod at the start (RSP) and the rod at the conclusion (RSP) of the cast with a straight line separating the two at the rod handle.
That separation represented the linear movement of the hand which occurred as the angular change in the position of the rod progressed, i.e. translation.
One simplistic view of STROKE and ARC is this combined with the concept that the stroke is the whole thing..... the entire movement of the hand and rod within which we have the angular movement of the rod butt section which for descriptive purposes can be isolated as the angle of change.
Lack of agreement exists as to whether linear movement of the rod (translation) which precedes rotation ("drag") should be included in the casting stroke. Once linear movement is mixed with rotation, however, they can only be separated conceptually by definition / description.... because they are occurring at the same time.
This angle of change is really the angle which subtends an an imaginary arc which can be imagined as the segment of a circle described by the path of the tip of an imaginary rod which doesn't bend. Since fly rods do bend, we choose to embrace a bit of a misnomer as we define CASTING ARC in such terms as the angular change in the position of the rod butt (or stiff butt section) from the start to the finish of the cast. We can take the bend out of the definition of casting arc (rod arc) by concentrating on the angular change of the rod butt.
Mel didn't otherwise distinguish between the "arc" and the "stroke" in his 1987 writings. Years later he did.
We have champion distance casters who use long strokes as well as great casting "arcs". Then there are a few, however, such as Steve Rajeff, who attains astounding distances with a short stroke and not so great an arc. I think Steve is able to do this because he has the power to cast an extremely stiff rod thus bending it to exactly the needed degree to match this bend to his narrow "arc" or rod butt angular change as he achieves an almost straight line path of his rod tip and sharp / tight loops and an explosive release.
Gordy
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[GH] From Mark Surtees, who follows up on part of my message :
Hi Gordy
Maybe I should stop commenting too…J
One last thing before I go though because I think this particular problem refers directly to some of the definitions issues we have had recently and perhaps why a common understanding of terms is so important.
Parts of a circle are something we are all taught at school and so we know that the words “arc” and “angle” are not interchangeable in a geometrical sense and yet we somehow have them muddled up in flyfishing vocabulary and we use one freely to mean the other.
If we seek to explain the change in position of a rod just by changes in angles and linear distances and the forces applied to the rod expressed also just in angular and linear terms then we run the risk of ignoring the fact that in reality these things are not objectively divisible and we deal not in straight lines and fixed angles but waves and curves, in ellipses and circles and even, occasionally, true arcs. I think that in the dim distant mists of time the _expression_ Casting Arc was used to loosely describe all these curves mixed together, curved hand paths, tip paths and the transit of the whole rod from the beginning to the end of the cast.
Widening the “Casting Arc”, if it is used in this way, involves not only increasing the angle but also lengthening or curving the hand paths, two co-occurring and mutually necessary changes in order to cast a longer line with a “straighter” tip path which will, in reality, most likely turn out to be an arc of an ellipse and not straight at all.
If we do not use “Casting Arc” in this way but use it to mean a change in angle then we can’t use it to imply that widening it alone, i.e. making it a bigger angle, will help achieve that elusive SLP, it will not. We have to explain the changes that we need to make in hand paths too otherwise we will get a very “unstraight” path indeed.
I’m getting back in the box now.
Mark
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[GH] Mark,
As you read my answer to Mark Milkovitch's message, you will note that I agree fully with you on the way we technically oft misuse the words "ARC" and "ANGLE".
The concept of elliptically curving hand paths and angular change of our rods while the rod itself is bending along with the time sequences involved can torture the mind as we try to apply strict scientific principles to all that is happening. The stuff of migraines !
We are not mathematicians or physicists, however. So we develop our "fly cast speak" so long as it serves to have us understand and teach casting. Bruce Richards refers to "engineer speak" as he and physicist Noel Perkins discuss casting details. "Engineer speak" might be superseded by
"Theoretical physics speak" as we go to the top of the mountain.
We can make this as simple as possible or as complicated as we wish. If we try hard we may achieve such physical and mathematical accuracy complete with formulae for proof that our students will no longer be able to understand us.
Bringing it down so that we can understand one another and our students can understand what we distill down to their level is, I think a realistic goal.
Gordy
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[GH]
Dusty Sprague comes in with an explanation which makes sense to me..... his way of looking at it :
Gordy,
I like to think of first imparting an adequate bend in the rod to move the amount of weight extended beyond the rod tip, then, finding the arc that provides a tight narrow loop, by false casting and adjusting that arc, mostly narrowing the arc, until a tight loop results. I rarely, if ever, first select a rod arc then try to match the bend to that arc...makes no sense to me to approach it that way.....I can't think of an instance when I'd want to do that.
Teaching it.....demo and explain adequate rod bend to cast the line, false casting, using arcs too wide creating wide loops then narrowing the arc to tighten the loop, then arcs too narrow to create tailing loops.
I emphasize using just enough force to bend the rod adequately for weight to be cast - length of line, weight/bulk of fly, wind conditions, then with minimum number of false casts narrow the arc to desired loop size then present. Working in the horizontal plane works well initially...students easily see loop narrowing as they narrow the arc. Works for me...
Best,
Dusty
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>From Dave Barron :
Gordy
Here is my take on question 21 or better yet questions 18-24. I always look for the short answer, but after I receive the short answer I always look at the candidate and ask why or how does that work. I am looking for some understand of what they just told me. I do not expect then to give me an MCI answer but I am looking for a little more than the pat answer.
A lot of time I will say this is not part of the test but is for extra credit and then I keep digging to find out how much they really know. A lot of times they will say something that is not totally correct and they will open a hole for me to dig in and see where it takes us. So I guess what I am saying is I take the short answer and see how much they really know.
Dave
David Barron
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[GH] Dave,
Your last comment strikes a chord.
I do the same thing when I test. I also do some teaching this way. This helps relax my candidate as I try to get the best out of him. Helps to break any "ice", too. Takes more time, but is worth it in my opinion.
Not all examiners agree with that style of testing. Some take the position that there should be no deviation from the test itself. I respect that..... but it isn't and never will be my style.
When and if my candidate is unsuccessful, he realizes that something has been learned along the way and is much more likely to be receptive to my post exam critique.
Ted Warren's comments on his experience speaks to this method of testing :-
"As a new CCI I liked the way my teachers taught me and the examiners handle my testing.
I was taught to answer the question that was ask and demonstrate it in a straight forward manner. Then I was encouraged to learn as much more about the item as I could along the way. I was instructed not to try to answer a question that was not ask, try to impress the examiners by going into more detail than required, or to venture into subject matters I did not fully understand.
On the test, the examiners first asked me to explain & demonstrate exactly as written in the test booklet. Once I had successfully done that (passed), they went further and asked me more questions and ask me to demonstrate other items related to the subject. But, this was done only after I had adequately answered the basic question & demonstrated the task.
The examiners explained this is what they would do before the testing but never indicated during the test whether I had passed each item or not. At times they taught gave me some additional information and some pointers on teaching. "
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