At the moment I am preparing a mentoring session for two anglers that are getting ready for two different casting certification tests. Writing is the best way I know of putting my ideas in order, so I have started this succinct list. A work in progress, probably. Comments are welcome.
The rod
- The function of the rod –casting-wise– is getting enough line speed.
- The longer the cast the higher the line speed we need.
- Spinning vs. Fly casting:
- Spinning: concentrated mass; not so many problems with timing, as you are always pulling on the whole mass; lure goes in the direction it was moving at launch.
- Fly casting: elongated mass; whole trajectory of tip matters in shaping the loop. And loop shape matters, a lot.
- Rod tip trajectory: slightly convex, very close to a straight line; good because of its efficiency regarding line speed and accuracy:
- A straight trajectory of the rod tip toward the target means that the force applied to the line goes in that same direction, instead of the multiple directions of a very convex tip path; no wasted energy.
- A straight trajectory shapes a more aerodynamic loop, with a narrow nose and a straight rod leg; no wasted energy.
- Straight rod tip trajectory, how is it possible?:
- Rod bend allows us to turn a curved motion of the rod butt into a –close to– straight motion of the rod tip. That is the main key in rod load.
- Rod tip trajectory depends on:
- Rod bend.
- Force applied by rod hand, which determines rod bend:
- No acceleration —no increase in rod butt speed— results in a curved rod tip path.
- Acceleration must be applied smoothly, that is, speed of the rod butt must increase progressively, without sudden peaks.
- Rod hand path.
- We want to propel the whole line so we have to apply force to the whole line at a time: slack is the enemy.
The hand
- The casting stroke has two parts:
- Translation of rod butt: backward/forward motion.
- Rotation of rod butt: angle change.
- Timing: Do you remember slack is the enemy? Starting the stroke before the line has straightened itself is another form of slack.
- Hauling: if you have two hands, why use only one?
- Speed added directly to the line.
- It is less tiring for the rod hand: effort is shared by both of them.
- More control at short and medium distances: muscular tension and control don’t get along well; relieved of work, the rod hand can trace its path more accurately.
- Tighter loops: rod counterflex opens the loop, and the bigger the rod bend the bigger its counterflex; paradoxically enough, in a well executed cast hauling results in less rod bend.
- Results in a more “balanced” casting motion: just like when running one arm moves forward while the other one moves backward.
- Line shooting:
- The timing to release the line?:
- You can shoot line only while the loop is alive, even if there is energy left in the line.
- Consequently, the longer the loop lifespan the longer the shooting time.
- Holding the line after loop formation shortens the loop lifespan.
- For maximum efficiency line should be released at loop formation, not after.
- The timing to release the line?:
The line
- The trajectory described by the line is the result of:
- Rod tip path
- Angle between line and rod during the stroke:
- For the line to fly as straight to the target as possible its backward and forward trajectories should be part of the same straight line:
- A tracking fault breaks that ideal straight line.
- A downward bound backcast breaks it as well.
- For the line to fly as straight to the target as possible its backward and forward trajectories should be part of the same straight line:
- Waves in the line: Can be generated at any point, but propagate down the line.
- Tailing loop:
- Wave generated by an anomaly –a fast down-up motion– in the rod tip path.
- Caused by a non-progressive increase in speed along the stroke. See Rod tip trajectory depends on… above.
- Dangling end:
- Wave generated by line sag in a long carry, or by line misalignment between backcast and forward cast.
- In the first case the wave is in the vertical plane.
- In the latter the wave is in the horizontal plane and can result in the line tip hooking to a side in the delivery of long casts.
- Wave generated by line sag in a long carry, or by line misalignment between backcast and forward cast.
- Tailing loop:
- Sinking lines:
- For the same AFFTA number they go farther and are better against the wind:
- Higher density results in less surface for the same mass.
- Less surface = less air drag.
- For the same sinking rate they get deep faster the higher their AFFTA number (see below).
- For the same AFFTA number they go farther and are better against the wind:
- Floating lines paradox:
- The higher their AFFTA number the farther they go and the better they penetrate the wind:
- That behavior regarding air drag is the result of a better mass/surface ratio.
- The higher their AFFTA number the farther they go and the better they penetrate the wind:
onemorelastcast.net 
You might find that rodtip path matters too in a spinning cast, rods work in exactly the same way, regardless of the reel type attached.
Looking forward to learn when loop formation happens 😊
Otherwise a very nice read! Good work!
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More than 40 years now that I used a spinner so you are probably right. 🙂
Thanks!
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No matter what you do, spinners don’t get tailing loops 🙂
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A rod is a rod 😊 one can just throw their mistakes further with a spinning rod, so far actually, that one usually don’t care about them 😂
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I should borrow one… when nobody is looking 😂
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Nice organized list Aiton, I only see the word “Slack” in one instance. Perhaps a bit more important than that?
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Definitely yes, Tim. Should find a suitable place for it.
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That’s the difference in mass distribution, not tip path 😉
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Really nice stuff Aitor!.
No mention of timing anywhere, or did I miss it?
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Yep, no mention of it. If we must apply force to the whole line at a time timing is implicit, as it is tracking. But you are right, that is too cryptic, I will add “timing” to the list.
Thanks!
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I know you know this but there may be a difference between training two people to be equally competent instructors and coaching two people to pass different certification assessments.
That may mean finding a way of expressing your list so that it ties in with the accepted mantras of the certification bodies. Assessors relax when they hear familiar words from the organisational codex,(even if its bollocks), after that it’s a bonus if they ask for, and get, a better explanation from the candidate.
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Yes, Mark, I know, and they are aware of that.
Anyway, only one goes for the CI; the other one is interested in the second level of PAIL —which isn’t about instructing, by the way— and the examiners are pretty much on the same wave. 🙂
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Aitor to your first point – The Function of the rod. I pose the question to my students “how much tip speed (power) do you need in a cast?” The answer of course is always a light bulb moment. You said “enough” but that’s too vague for me. My answer is “only sufficient to get the fly to the target under the circumstances”.
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Good point, Morsie. Less effort is what we should have always in mind.
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Love it, I often wonder what % of fly fishers fully understand the principles of fly casting. I know fishing and casting are two totally different things. However, I am of the belief that better casting leads to a more enjoyable days fishing as the environment and weather conditions are always different. I am amazed & thankful at how helpful everybody is in helping me with my CI. Fly fishers are a special bush. I am looking forward to the experience and hopefully I will be able to reward everybody by pass the exam.
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Go for it!
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Hi Aitor, well put, fine list! About “rod tip trajectory”, I prefer to call that rod tip path. Trajectory is what I match to reach the target. It can be upward, horizontal or low on the delivery fc (opposite in the bc). My rod tip path obviously is related to launch trajectory. BUT it (the accelerational rod tip path) often isn’t aligned with the target! During unrolling gravity works. Thus casting in just enough line speed often means to aim launch trajectory above the target. Regards Bernd
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Hi Bernd,
I agree. The target isn’t a point on the water surface but in the air above it.
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