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efficiency vs effectiveness in fly casting

Montag, Oktober 19th, 2020

Sometimes I read a comment like this: „As I’m able to cast further with an (almost) rigid fly rod, this one must be more efficient than a higher flexible one”. Obviously a lot of people are focussing on the casting distance only to make a statement on efficiency and this is absolutely understandable because in contrast to the effort, input energy respectively the casting distance of the cast is easy to measure. But the casting distance alone could basically tell something about the effectiveness, because for effectiveness only the result, casting distance, output respectively counts and not what input is needed to reach the result1.

To estimate the efficiency the amount of the input einergy is required too since efficiency is defined as the ratio of the output and the input. The higher the output generated with less input, the more efficient. Our economy is based on efficiency, companies that only focus on effectiveness are at risk of going bankrupt sooner or later (because their output, their product respectively might be too expensive). So a little more economic thoughts in fly casting can’t hurt. To me efficiency plays an important role in common fly casting as it allows to reduce the effort the caster needs to bring the fly to the target.

The optimal efficiency can be reached neither by a rigid nor by a flabby fly rod. The optimum in efficiency lies in between these two borderline assumed fly rod types, hence the efficiency consequently depends on the deflection. In this paper I won’t go into the reasons why efficiency depends on the deflection, in case of further interests in this topic, section F of my “Experimental investigations on the fly rod deflection” is a good starting point2.

Of course there are other aspects on efficiency depending on the casters ability like minimizing the false casts, a proper grip tension, a small counterflex, a perfect haul and so on and I’m sure a lot of advanced fly casters have intuitively efficiency with on board – but talking about efficiency always means to take the deflection into account too.

In terms of competition fly casting my view on efficiency is a bit different. In this sport only the score decides on the success, hence the caster is basically focused on the best possible output, effectiveness respectively. Efficiency tend to be a bit subordinated as the competition caster is willing to put all his effort into the cast in order to win the contest – no matter what it “costs”. So in competition casting less deflection that causes a longer lever arm that in turn results basically in a higher effectiveness could be the key for success. Primarily high leverage (in combination with perfect hauling of course) takes the competition caster on top of the ranking.

A very raw example to understand the difference between effectiveness and efficiency by comparing the rigid and the flexible fly rod of the same length could be:

Fly rod typeOutput energy (indicated by the possible distance) Required input energy at the grip / comfort
Rigid (~ultra fast, nearly rigid)100% (maximum)100% => not comfortable at all (aching arm)
Flexible (~moderate fast)~ more than 90%~ 50% => comfortable
Rigid (~ultra fast, nearly rigid)~ 90%~ 90% => not comfortable
Flexible (~moderate fast)~ 95% (limit reached in dependence on rod action)~ maybe a be less than 100 %

=> moderate comfortable

Note: The chart above shows only a raw tendency, the percentages could vary a lot in dependence of casting gear and casting length

Looking on the chart it becomes evident, why competition distance caster prefer very stiff fly rods. They have to achieve 100% of the maximum possible distance in order to win the contest and they are ready to muster all the energy they can. The fly fisherman who needs longer casts over a longer period of time will rather choose a flexible fly rod not only as it provides advantages by carrying the tip easier on a straight path and playing a fish, but also as it provides a better energy transfer. According to the chart the fly fisherman might be not able to achieve the maximum possible casting distance, but a slightly less possible distance goes hand in hand with a significant decrease in effort, input energy respectively and with an increase of casting comfort ! In addition if the rigid fly rod is casted to the same distance which is possible for the flexible fly rod, then the flexible one will still need significant less effort, input energy respectively.

Years ago I had my personal heureka effect regarding the difference between efficiency and effectiveness during fly fishing at the coast. For this kind of fishing I usually use 10 feed long class 6 fly rods. Some days before fishing I bought a new and very stiff “ultra fast” fly rod with an extreme tip action and expected my distance will increase. In fact it did, I was able to cast a bit further by using my brand new ultra fast fly rod (in comparison to my softer fly rod about 1 Meter more in average, not really much but however this further distance could sometimes be important to reach the fish). But after a short period of time (about 15 minutes) I was not able to keep the distance since my casting arm, especially my forearm, weakens and was aching. I had to reduce my casting distance significantly (in average more than 8 meters for sure) to avoid this. Than I switched to my softer fly rod (which is not a noodle at all). With this softer fly rod my casts were almost as far as the farthest possible with the ultra fast rod, but I was able to keep my casting distance uniform up to the same high distance. There was no need to reduce the casting distance since all casts were very comfortable requiring a significant smaller effort and even after a whole day long of casting my casting arm didn’t weaken.

For the stiffer fly rod dropping to a lower carry of elbow could help on the forward cast to avoid to weaken the casting arm, but this will not change the tendency that a softer fly rod basically provides a better energy transfer along the fly rod shaft compared to an (almost) rigid one. If this dropping movement relieves the casting arm when casting a stiffer fly rod, then it will relieve the casting arm even more when casting a softer one.

To me this example is a very practical fishing situation holding true not only for coastal fly fishing and my experiences match my investigation as well as 2D modelling.

There is a quite nice analogy suitable to work out the difference between effectiveness and efficiency: The car race !

In this analogy a formula 1 car and a sports car (e.g. Porsche)3 is compared. The formula 1 car will always win a race (output energy), since it was developed to gain the highest speed. But the price is a very high gasoline consumption (input energy), lacking comfort and a consumed engine after the race (aching casting arm). If the formula 1 car drives the same speed as the sports car is able to drive maximal (same output energy), then the gasoline consumption of the formula 1 car will be still significant higher compared to the sports car. Hence for the same output, speed respectively of both racing cars the sports car needs significant less input. Further more the sports car comes along with a higher driving comfort due to a better damping and its engine is designed to keep the high speed for a significant longer period of time4. In terms of efficiency the sports car will always win the comparison – like the flexible fly rod does in comparison to the rigid one !

Back to fly casting. Due to the foregoing reasons my comparison between the rigid (~ultra fast) and the softer fly rod results in the following tendency:

  1. To achieve maximal casting distance for a shorter period of time (like competition casting) I will always choose the stiffer fly rod in order to cast “the one meter further” to reach the fish or to win the contest.
  2. To achieve a high casting distance over a very long period of time, the whole day long respectively, I will always choose the softer fly rod (since I’m aware that it supports the energy transfer from the butt towards the tip). The more as I know that after a short period of time I will cast further as I would do using the stiffer fly rod because the softer fly rod won’t weaken my casting arm.



1 The opening comment would be correct if the term “more efficient” was replaced by “more effective”.

2 Just the hint that the fly rod not only provides the spring effect but further more redistributes the angular momentum (redistribution effect), which causes a shift / concentration of some angular momentum towards the tip of the fly rod resulting in a better energy transfer along the fly rod shaft.

3 The formula 1 car represents the rigid fly rod, the sports car the flexible one.

4 At the end of a race the engine of a formula 1 car is usually consumed and needs to be replaced.


Gewünschte Präsentation der Fliege mit so wenig Aufwand wie möglich

Donnerstag, Mai 23rd, 2019

desired fly delivery by using as little effort as possible

Dienstag, Mai 14th, 2019

when the whip joins the pirouette

Donnerstag, Februar 7th, 2019

Since the publication of my “Experimental investigations on the fly rod deflection” a longer time has passed and meanwhile there have been some discussions (especially on the forum) about the concept Franz- Josef and I have choosen to clarify the redistribution of angular momentum (we call it “redistribution effect”). The preface Franz- Josef wrote for my investigations expresses the concept how we both tried to clarify the physical relations well and we are still convinced that this concept enables much more people to follow the content than too theoretical approaches using differential equations. In section F1 as well as in annex 2 and 3 of my investigations Franz- Josef and I are mainly talking about the “pirouette” and the “whip” effect in order to explain the redistribution of angular momentum. This essay is going to look with fresh eyes on the interrelation between the “pirouette” and the “whip” effect and how both effects redistribute of angular momentum.

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Der enttäuschte GF

Freitag, Januar 4th, 2019

Seit einiger Zeit bringt Günter Feuerstein auf seiner Homepage (letzter Absatz) seine “Enttäuschung” darüber zum Ausdruck, dass u.a. ich nicht die Instruktor- Prüfung der EFFA abgelegt habe. Ich frage mich, warum  Günter Feuerstein dies veröffentlichen muss ? Dafür mag es viele Beweggründe geben, die tendenziell eines gemeinsam haben: sie werfen kein gutes Licht auf den “enttäuschten” Günter Feuerstein. Aus meiner Sicht ist diese Veröffentlichung keine gute Werbung für die EFFA.

“Indem man über andere schlecht redet, macht man sich selbst nicht besser” (Konfuzius).

Manus agere

Donnerstag, Oktober 11th, 2018

Der lateinische Begriff „manus agere“ wird gerne mit „die Hand führen“ übersetzt und gilt als die sprachliche Wurzel für das „Management“. Am häufigsten wird das Management im Zusammenhang mit der Führung von Unternehmen benutzt, es spielt aber ebenso beim Organisieren des privaten Lebens eine wichtige Rolle.

Insbesondere dem wörtlichen Sinne von Management kommt mit dem „Führen der Hand“ auch beim Fliegenwerfen eine Bedeutung zu. Die Hände verbinden den Körper des Werfers mit seinem Gerät, die eine Hand des Werfers „führt“ die Fliegenrute, die andere die Fliegenschnur. Beide Hände übertragen den körperlichen Aufwand des Werfers in die Fliegenrute und in die Fliegenschnur und nur wenn dieser Aufwand zum richtigen Zeitpunkt eingegeben wird, kann der Wurf gelingen oder verbessert werden. Wie und wann die Hände des Werfers den Aufwand in die Fliegenrute und in die Fliegenschnur übertragen, entscheidet maßgeblich über die Qualität des Fliegenwurfes.

Aus vorgenannten Gründen liegt es nahe, dass der Instruktor die Hände seines Schülers sehr genau betrachtet, um herauszufinden, wie sie den Wurf „managen“. Einige Instruktoren belassen es beim Anschauen der Hände und das ist in vielen Fällen auch ausreichend. Meiner Erfahrung nach kann der Instruktor aber weitere wertvolle Informationen von seinem Schüler erhalten, wenn er seine Hand übergreift, wodurch er das Management seines Schülers besser „be-greifen“ kann.

Diese Interaktion zwischen dem Instruktor und dem Schüler funktioniert in beide Richtungen. Zuerst „be-greift“ der Instruktor den eingegebenen Aufwand seines Schülers, wenn seine Hand der Hand des Schülers passiv folgt. Er kann dann im nächsten Schritt Korrekturen und Verbesserungen anbringen, indem er mit seiner Hand die Hand des Schülers aktiv führt. Der Instruktor übernimmt die Führung über den Wurf und der Schüler erfährt auf direktem Wege, wie und wann er seinen Aufwand in die Fliegenrute und in die Fliegenschnur einbringen sollte.

Persönlich bin ich davon überzeugt, dass „die Hand führen“ ein sehr effizientes Instrument ist, den Fliegenwurf zu vermitteln, weshalb es von vielen Instruktoren benutzt wird. Während meiner eigenen Zeit als Schüler konnte ich schneller „be-greifen“, worauf es meinem Lehrer ankam. Als Instruktor kann ich viele Korrekturen und Verbesserungen bei Schülern anbringen, die ich allein vom Anschauen des Wurfes nicht hätte anbringen können (insbesondere, wenn der Schüler zu früh „Druck“ / Aufwand in die Fliegenrute eingibt).

Mit „Die Hand führen“ kann der Instruktor nicht nur den grundlegenden Bewegungsablauf des Fliegenwurfes, sondern auch den „Aufwand zum richtigen Zeitpunkt“ vermitteln, der für das effiziente Fliegenwerfen eine wichtige Rolle spielt.

manus agere

Donnerstag, Oktober 11th, 2018

The Latin term „manus agere“ is often translated as „leading the hand” and is considered as the linguistic root of the “management”. Most frequently the management is used in relation to the leadership of a company, but it plays also an important role even in the private life.

Especially the literal sense of the management, the “leading the hand” has also a meaning in terms of fly casting. The hands are connecting the body of the caster with the gear, one hand “leads” the fly rod, the other hand the fly line. Both hands transfer the input of the caster’s body into the fly rod as well as into the fly line and only if this input is taking place at the right time the fly cast can succeed or can be improved. How and when both hands of the caster transfer the input into the fly rod and fly line is the key of the quality of the fly cast.

Due to the foregoing reasons it makes sense that the instructor is watching the hands of his student in order to seek out how he “manages” the fly cast. Some instructors leave it at watching the hands and in most cases this is sufficient. In my experience the instructor is able to receive further important informations from the student by gripping his hand in order to “grip”, understand respectively the management of his student better.

This interaction between the instructor and his student is working in both directions. First the instructor “grips”, understand respectively the used input of his student when his hand follows the hand of the student passively. In the following step he can attach corrections or improvements by leading the hand of the student with his hand. The instructor is taking the leadership about the casting stroke and the student can notice directly, when and how he should apply his input into the fly rod and the fly line.

Personally I am convinced that “leading the hand” represents a very efficient way to convey the fly cast, for which reason a lot of instructors are already using this method. During my own time as a student I was able to “grip” what mattered my teacher. As an instructor I was able to attach corrections and improvements to my students, which I would not be able to fix by only watching their fly cast (especially when the student tends to apply the force, input respectively too early or suddenly).

With „leading the hand“ the instructor can not only convey the basic motions of the fly cast, but also convey the right time of the input, which is playing an important role in terms of an efficient fly cast.

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input at the right time

Sonntag, September 2nd, 2018

Today it is established, that the fly rod not only stores energy (potential spring energy), but also includes a redistribution of the introduced energy – consisting the interrelation of the modification of the moment of inertia and the redistribution of angular momentum, called the redistribution effect – , which leads to an energy transfer from the grip towards the tip of the fly rod propelling the fly line at last[1]. This energy transfer allows the fly caster to generate the line speed needed to hit the target by minimizing his effort.


Since the redistribution effect depends on the deflection, efficiency is hard to teach. To determine the “efficient deflection” during a casting lesson seems to be nearly impossible. But to me this difficulty is not an excuse to hang on longstanding teaching elements, but a challenge to identify those elements, which are important for efficiency !

A longstanding and accepted teaching element is “rotation at the right time”. But the problem with this element is, that nobody knows the efficiency of the cast. Since this teaching element doesn’t care a lot about the meaning of the deflection[2], it stays too much on the surface (as I already wrote in my essay “Fly rod deflection and rotation 03/2017)” and might be useful to teach effectiveness, but not necessarily efficiency. Obviously a “deeper” teaching element below the surface of “rotation at the right time” is needed to face efficiency[3].

Motion properties

There are already some motion properties known, which favour an efficient fly cast. In the video ”What matters an efficient fly cast” – – I worked out properties, which are important in my view. They are: a

  • significant translatory motion at the beginning of the fly cast
  • rotary motion which prevails very late (delayed rotation)
  • damping of the fly rod during the later rotary motion
  • harmonious movement through the entire casting stroke

Personally I was able to adjust my casting motions to the above enumerated motion properties by practicing with an ultra soft fly rod for a certain period of time[4]. The soft fly rod represents rather a “deflection dominated” mean, for which reason a softer fly rod is basically able to trigger the redistribution effect better than a stiffer fly rod, since a stiffer fly rod represents rather a “lever arm dominated” mean. If the caster tries to cast a softer fly rod lever arm dominated by using a shorter casting arc and by applying the required effort during a shorter time span as it works well for stiffer fly rods, for a softer fly rod the cast would probably fail. That is because a softer fly rod doesn’t allow the caster to use generous deviation from the above enumerated motion properties since they highlight a deflection dominated cast.

By practicing with softer fly rods the caster is forced to think about the distribution of the effort he applies in the grip over the entire casting stroke, especially when casting a longer fly line. Finally, if a stiffer fly rod is casted similar a softer one, the lever arm property joins the redistribution effect which leads to a higher efficiency.

Grip tension

Applying effort into the fly rod requires grip tension and the amount of grip tension depends on the required effort. The caster can loosen grip tension when no effort is needed and must tense it up when effort is needed. The caster notices, that for a soft fly rod the casting stroke works best if the grip tension is smoothly increased up to a maximum around the vertical grip position for a very short moment, while grip tension could be smoothly decreased again during the further casting stroke when unloading prevails[5].

In any case in terms of efficiency it is better to focus on the grip tension instead to focus on the rotation. This seems to be a good way to ensure that the above enumerated (deflection dominated) properties are considered. The longer the carried fly line is, the more the above enumerated motion properties must be respected to ensure a proper fly cast.

In the video “Energy transfer along the fly rod shaft” – – I explain the “grip tension at the right time” (at 0:30 min) as it is useful for a better energy transfer. The idea of “grip tension at the right time” I watched first in the video “Dynamics of Fly Casting” by Joan Wulff, in which she squeezed a sponge around the vertical grip position to visualize the moment the caster should apply the highest effort.

Input in relation to rotation

The grip tension is the requirement for the input, energy or work respectively the caster applies into the fly rod[6]. Thus to me the appellation “input at the right time” is a proper advanced teaching element, which faces an efficient fly cast much better than “rotation at the right time”. In contrast to “rotation at the right time” with “input at the right time” the caster is able to gain a better control over the deflection as it is not only important to achieve a better energy transfer, but also to minimize the waste of energy due to an improved damping[7].

The rotary motion is the most important motion property of the input. If the caster neglects the rotation during he applies his input, the fly rod will respond with a very poor output, cast respectively[8]. As a big advantage of the teaching element “input at the right time” it is focussing not only on the rotation, but pays also a higher attention to the other important motion properties enumerated above – especially to the translatory motion[9].

Even the 5th principle of fly casting[10] stated by Jay and Bill Gammel is talking about the “power” instead of the “rotation” in the right amount and place during the casting stroke. It seems they have understood that “power” as a synonym for the input is a better principle to describe the casting stroke than “rotation” could be.

Right time and phase shift

Both teaching elements are talking about the “right time” and the caster may ask, when the right time is. For rotation as well as for input the “right time” depends basically on the casters aim, the rod action, the casting length and how especially the fly rod and the fly line are balanced.  But there are tendencies showing the differences.

The “rotation at the right time” still holds true, if the caster doesn’t delay the rotation and if he still applies further “input” at the end of the casting stroke when the grip already has passed the vertical position in order to “kick” or “boost” the cast. The benefit of this further “input“ is rather less in relation to its drawback as it will produce a big waste of energy indicated by a big counterflex (bad damping).

In contrast to this the “right time” for the input is always delayed and its highest value occurs around the vertical grip position. It pays attention to a kind of phase shift between the highest input and the highest output, velocity of the tip of the fly rod respectively as the input precedes the output. This phase shift is vital in terms of efficiency since it allows the caster to reduce his input while at the same time the tip of the fly rod still gains velocity[11]. The phase shift explains, why a “kick” or “boost” at the very end of the casting stroke is detrimental in terms of efficiency.   

The “right time” for the rotation tends not to face the phase shifting as the “right time” for the input does and this is a further reason why rotation alone can’t face efficiency.

Technical point of view

Engineers and scientists usually investigate the dynamic behavior of complex bodies by stimulating them with different input functions (variation of the input) in order to determine the optimum output (input and output as a function of energy, work respectively). If the optimum output is determined, they have detected the best input function (“input at the right time”). Nothing else should hold true for the fly rod as it represents a complex and flexible slim body. The output on the one end (the tip) depends on the input on the other end (the grip). If the input is accentuated on one motion property like rotation, there is a risk to oversee the interrelation of the other important properties, which must be involved to detect the best input function possible !

Even a technical point of view clearly shows, that the teaching element “rotation at the right time” could lack some important motion properties in terms of efficiency.


The softer fly rod supports the caster to find out the advantages of the deflection. He will be able to recognize the phase shift between the highest input and the highest output and will intuitively look for the best input function (“input at the right time”) needed to generate a deflection, which leads to the best output in terms of efficiency. If he switches then to a stiffer fly rod after he has adjusted his motion properties accordingly, he might be surprised how less effort / “input” is needed to generate a proper line speed. He has learned to control the deflection better, which means that aside the spring effect the redistribution effect plays a higher and the waste of energy a minor role.

Efficiency in fly casting doesn’t mean that the caster has to decide between the deflection or the lever arm property of the fly rod. It rather means to get closer to the best interrelation of both the deflection and the lever arm. The teaching element “rotation at the right time” highlights the lever arm property of the fly rod and tends to neglect the deflection property. In comparison to this “input at the right time” combines both properties better so that they join to an efficient fly cast. Therefore “input at the right time” is a “deeper” and more complete teaching element for advanced fly casters than “rotation at the right time” could be.

In addition the teaching element “input at the right time” is already used to explain the right moment the line hand has to haul, introducing “input”, energy respectively. For which reason this teaching element should not work for the rod hand as well ?

Is it too complicate to teach ? Is it too complicate to leave it at “rotation at the right time” instead ? For advanced fly casters I don’t think so. To me it is worth to think about teaching elements which are closer to an efficient, power minimized fly cast[12]!

In my experience the teaching element “input at the right time” even works practicing with stiffer fly rods (if a softer fly rod is not available) to convey advanced fly casters what matters an efficient, power minimized fly cast.  

Many thanks to Franz- Josef, who has reviewed this essay.

The following outline shows a simplified classification of some elements of the fly cast as I see them

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[1] More detailed Information about the redistribution of angular momentum and the modification of the moment of inertia (redistribution effect) can be found in my “Experimental investigations on the fly rod deflection” (Rev. 2.0 – November 2014), section F1 and annex 2.

[2] In fact the deflection is the requirement for efficiency.

[3] A good explanation about the difference of „effectiveness“ and „efficiency“ could be found here: and

[4] In the IFFF magazine “THE LOOP” January – July 2017 there is an article published about my experience practicing with ultra soft fly rods.

[5] Especially during the unloading phase of the fly rod aside the spring effect for bigger deflections the energy of the lower mass elements contributes  to generate the velocity of the upper mass elements leading to the redistribution effect accompanied by the energy transfer and a kind of “self dynamic” (self dynamic mechanism) of the fly rod. Therefore the caster is able to decrease his grip tension during the later rotation though the tip of the fly rod still gains velocity.

[6] Some people think that rather the force the caster must appliy into the grip describes his effort. As the fly line is propeled by the energy and not by force of the tip, the same physical unit should be compared with each other  (otherwise apples would be compared to pears).

[7] In addition the figure XI of my analysis „Experimental investigations on the fly rod deflection“ has estimated how the course of the introduced input of energy and momentum transfers the kinetic energy to the tip and leads to its acceleration (green graph for the flexible fly rod). The rotation is an important aspect which goes together with the input of energy and momentum.

[8] So the caster didn’t use “input at the right time” in this case.

[9] See my essay „The meaning of the translatory motion in fly casting”.

[10] The 5th principle is: “Power must be applied in a proper amount and in a proper place during the stroke”.

[11] For a rigid fly rod there is no phase shift due to the lacking spring and redistribution effect.

[12] Fly fishers, who want to reduce their effort when fishing the whole day long e.g. at bigger rivers, lakes or at the coast, could profit a lot by casting efficiently.


starting the haul for the backcast at the guide ring

Dienstag, Juni 12th, 2018

When casting together with other advanced fly fishers I’m often been asked about my opinion how I think they could improve their casting. Especially seeing them going for longer casts in many cases I recommend to delay the rotation further. The astonished reactions that I get then are showing that some fly fishers think they rotate “as delayed as possible” – but in fact they don’t.

Over a decade ago I saw a hauling variant used by the danish fly fisher Nicolai Eriksen, who starts the haul for the backcast at the guide ring. I noticed that the line hand was only able to reach the guide ring if the rod hand is situated in a rear position far behind the body axis. Furthermore in this position the wrist could be relieved if the grip of the fly rod is leaned against the forearm. For the rod hand I found this to be a good initial position to delay the rotation (see video below) !

Trying this the first time was quite unfamiliar, but after a couple of time practicing this hauling variant I realized that I was able to delay my rotation further – the more the grip of the fly rod is leaned against the forearm. After adjusting my motions accordingly it works even without hauling or starting the haul lower (not at the level of the guide ring).

To me this hauling variant is a good exercise for fly fishers to check if their casting motions are adapted to a very delayed rotation. Although I normally don’t use this haul variant in fishing situations I’m convinced that this exercise can improved the casting stroke and that it is useful especially casting softer fly rods for distance.

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feelings and facts in fly casting

Mittwoch, Mai 30th, 2018

When I first stated about 10 years ago, that according to my feeling the ‘load’, deflection respectively of the fly rod could provide a significant advantage in term of minimizing the casters effort, I earned a lot of objections. A lot of people replied that the meaning of the ‘load’ is absolutely overrated. In their opinion the ‘load’ provides basically geometrical advantages – especially to carry the tip of a fly rod on a straigh path. They base their opinion basically on results of the following physical investigations:

  1. “The Rod & The Cast” by Lövoll / Borger from 2007. This great investigation pointed e.g. out, that the stored energy of the fly rod contributes about 20% to the final tip speed, what is rather less.
  2. Outcome of modelling the fly cast with a simple harmonic oscillator. This 1D model pointed out, that the deflection indeed provides an advantage in terms of efficiency (ratio of the output / input energy), but this advantage will be more or less completely eaten up by the energy loss caused by both the counterflex and the energy conversion from the stored back into the kinetic, which waste energy.

Today more recent insights are showing that the deflection (and the ‘load’ as a part of it) is the requirement for a significant better energy transfer along the fly rod shaft, which rises the efficiency. After I’ve occupied myself with the aforementioned investigations I came to the following valuation:

To 1. = The energy transfer was not in the focus of the investigations by Lövoll / Borger. Hence to claim the ‘load’ – the more as it occurs together with the deflection – can’t play an important role since it contributes rather less to the final tip speed is risky.

To 2. = A simple 1D model is basically not able to face the redistribution of energy, angular momentum respectively taking place due to the deflection. On the other hand 2D models are showing, that aside the ‘load’ an energy redistribution, redistribution of angular momentum respectively takes place enabling a better energy transfer from the grip towards the tip of the fly rod (made possible by the modification of the moment of inertia in combination with the varying angular velocities of the mass elements of the fly rod – see the following video). Further more the disadvantage of the counterflex must not be as big as assumed. I’ve read about an average counterflex by about 66% in comparison of the biggest previous deflection, but it is fair to say that an average reduction on below 20% is absolutely possible.

Physical facts are saying that the deflection provides a big potential regarding energy transfer and it is up to the caster to make the most of it. So in terms of minimizing the casters effort the meaning of the deflection is not at all overrated. To me it is good to know that my feeling I have over a decade matches physical relations. The physical background of 1. and 2. can’t be approached for explaining the entire characteristics of the fly rod. Whatever ‘feeling’ is supposed to tell.

Of course in fly fishing there are several points which are important to catch the fish – but for the most common fishing situations the fly fisher can profit by hitting the target with less effort possible – and controlling the deflection is a very important key to it (see the following video).

“The flexible elastic lever is a very smart mean to maximize energy in the line and minimize the one left in the rod.” (Merlin from sexyloops, 05/2018)

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