I’m always looking to improve some aspect of my casting which usually means finding ways of increasing efficiency and thus reducing effort. At present I’m trying to use a more extensive thrust (full arm extension) finish, especially on my delivery. I also want to see if I can enhance my backcast by adding some sort of thrust component to it as well for both false casting and for delivery off the backcast. However, that will have to wait because I have returned from another Tassie trip with some work to do on my backcast and I’ll post about that another time.

Mechanics

The heading of this post partly answers the “why” question. Why do this? If we take a mechanics perspective it is fairly easy to understand the explanation. By using a longer stroke we can do more Work on the line. Work is Force by distance so how much Force is applied for what distance determines the Work we do on the fly line and thus the kinetic energy we put into it.

Pardon my repetition but the relevant Force is not any old force going anywhere, it’s a vector Force, a net Force in the intended direction of the cast as we accelerate the mass of the fly line. To do X amount of Work we can apply more Force over less distance or less Force over more distance.

Biomechanics and Sensory Motor Control

We know from biomechanics that the bigger muscles are closer (proximal) to the centre of our bodies. The smaller muscles are further away (distal). The bigger muscles are better at grunt and the smaller ones at finesse. So if we lengthen the stroke we might well be taking the pressure off the smaller muscles by using some of the bigger ones to a greater extent. That means less effort is required from the distal muscles which means better control.

If I detach the rod butt and, using a basic or foundation cast movement, make a slow forward cast and stop I can see that there is still a bend at my elbow between the forearm and upper arm. Secondly, my rod hand is more or less in the same plane as my inner forearm. This is true regardless of my grip type (which in practice varies from thumb on top to a V grip).

Now, if I repeat the forward cast and this time fully extend my arm, the bend between forearm and upper arm disappears and, somewhat unexpectedly, I notice significantly greater movement of my hand which is now cocked (extended) further and somewhat turned in (pronated). The exact differences in angles may vary from person to person so I’m not concerned to make an exact measurement of the degree change. The difference is obvious and significant just watching where and how my hand finishes.

Back to casting mechanics. As the fly rod is a lever that amplifies the travel distance of the rod hand, you can bet that the rod tip is describing a much long path with full arm extension than it does with partial arm extension. From our body’s point of view the difference isn’t so much but from the rod tip’s perspective, the difference is very significant. It gets translated roughly the same distance in both cases but rotated a lot further when we thrust, fully extending the arm and pronating our rod hand.

From the perspective of sensory motor control we know from well accepted studies that we can be more precise in our movements if we move slower which is exactly what a longer stroke allows. Elsewhere on the site there is plenty more detail on the three perspectives I’ve just touched on – mechanics, biomechanics and sensory motor learning.

The Story of How

The other question is “how” – how to make a thrust finish, how to incorporate it and how did I get the idea of making a more expansive thrust finish on the delivery. Just for the heck of it I’m going to start with last part and expect that along the way we will cover the other two “how” questions.
If you watch any seriously competent caster the odds are you will see a thrust finish on their long casts. For example, find some footage of Joan Wulff finishing a long cast. Her casting arm will be fully extended, her torso rotated slightly toward the target and her weight has moved entirely to the front leg. It looks nice and it works well. As Steve Raejeff has put it, for distance casting his stop takes place when he runs out of arm, ie after full extension.

For many years I’ve incorporated a thrust into my longer casts. For much of that time I wasn’t thinking about anything to do with physics, biomechanics or sensory motor learning. It worked so I used it. Then, about a year or so ago I started playing with TLT, lancio angolato and svirgolato. These casts are not about prodigious distance but rather about subtle and artful control. So, I was intrigued and started seeing what I could take from lancio angolato, which finishes with an emphatic and extensive thrust, and import it into my standard overhead casting. It produces an extremely narrow loop, helpful for sneaking casts under the vegetation. What I noticed straight away was the extra zip it injected in all casts from shortish to quite long. (Little wonder that lancio angolato adds zip – lots more Work is being done.)

The next step was to play around with this expanded version of a thrust and modify it to fit casts of different types, lengths and applications. I find that reverting to a sidecast is often helpful. Going back to the start of the triangle method, as it were, allows me to see what is going on, what is working well and what isn’t. Visual clues and adjustments inform the sensory motor system nicely because we are built to use our sight as a primary sense. It gives us data that we won’t necessarily get or use just from feel alone.

Out on the water I get to play with new things and see if they work for me. A couple of examples. Casting upwind – angle up behind and then use the thrust in the low forward delivery. Casting across and maybe slightly upwind to cover a riser and you want it see the fly before the tippet? Side cast with thrust and let the wind impede the last bit of the turnover to keep the fly slightly downwind. The thrust is now a variation of technique I can and do improvise with. You can use it squared up with the basic or foundation cast. You can use it with a partially or fully open stance employing a much wider casting arc.

For medium long to long casts I began using a modified form of thrust which reduced total effort. I’m still refining the technique for the forward cast but it’s clearly there to stay. It allows me to use a longer stroke without excessive rotation at the finish.

Try this at home. Square up and use a foundation overhead cast out to a medium distance. Don’t stop and then drop the rod to open the loop. Stop “high” and keep your loop tight. Now, look at the angle between your upper arm and your forearm. As already described, my guess is that your arm won’t be straight. There will be a slight bend at the elbow and your hand will be in a similar position to mine. When I see that I see opportunity to get another little bit from the upper arm, forearm and hand. With an open stance a little extra contribution from final shoulder rotation and weight transfer can be added to the list. All this is what a thrust finish offers. It’s almost like a secondary sequence from proximal to distal. Why let the opportunity pass you by?

A nicely executed thrust will extend the Straight Line Path, that is, it will increase net Force in the intended direction of the cast. When my cast finishes with a thrust I often seem to get narrower loops and that could be just an SLP thing. It may also be that in thrusting we “push into the bend” of the rod, delay straightening (maintaining rod flex longer) and reducing counterflex. I don’t have the mo-cap footage to provide the proof but I suspect that is what’s happening.

If you don’t presently use a thrust finish, try it and see if it works for you. If you do already finish with a thrust try making a more emphatic thrust and see how that goes.