This is a for beginners – the basic description of the casting arc needed for a short cast.
The last blog considered a tracking fault i.e., what happens if there is too much bending (radial movement) of the wrist (abduction) in the horizontal plane.
So, it’s logical to consider what happens when we over-abduct the wrist in the vertical plane. The angle between the underarm and the rod then becomes, say 90 degrees. Beginners and intermediate casters do this frequently on their back-casts. This will send the line careening down behind the caster, and thus it will be traveling in a great big loop. When the wrist bending (radial movement – abduction) is kept minimal and the rod is stopped just past vertical, the caster will have a much straighter line behind and now has consequently the foundation for a good forward cast.
Now, on to the forward cast. The same rule applies. The backcast and the forward cast should be symmetric. Therefore, we need to stop the rod high on the forward cast to send the line straight.
Beginners frequently bring the rod tip too far down instead of stopping it higher. That leads the fly line to form a big inefficient loop going nowhere. What we want to do is to stop the rod tip high and shape the top leg (fly leg) straight.
Now the crucial feat is to make the rod tip travel from the back stop B to the front stop A (orange lines) in a straight line. We can do that by bending the rod against the mass of the line behind it (plus the inertia of the rod itself). We start from a standstill, smoothly accelerate the rod, and bring it to an abrupt stop when we reach the front stop. That will send the line over the tip in a straight line making for an efficient cast. To obtain this straight line we must practice a lot. There is no getting around that one.
If we don’t accelerate and don’t bend the rod, there will be no straight line, but an upward curve, and the loop becomes large and inefficient. If we use too much force the tip path will dip down and we get a tailing loop.