Taper Functionality
Taper design affects a number of important aspects of a cast. By modifying the different components of a fly line you can change:
- How much line can be carried while false casting
- How large or air resistant of a fly it will cast
- How far it will shoot
- How quickly it will load a rod
- How far it will roll cast
- How smoothly it will cast
- How aggressively it will turn over the leader and fly
Let’s look at the different components of fly lines in the diagram below. The upper line is a Double Taper and the lower line is a Weight Forward.
At the front of the line you will have a Tip section. The tip is usually from 6 to 12 inches in length. The purpose of the tip is to allow transition to the leader by adding some kind of "butt section" to which you connect the leader. On sinking lines this butt section is usually a braided loop or a loop that was built into the line, while on floating lines it is usually a section of monofilament line. The tip also allows kinetic energy to transition from the front taper through the "butt section" or loop to the leader.
The second element is the Front Taper. This determines how quickly and how forcefully the line turns over. A shorter head will turn over quicker and more forcefully than a longer front taper. Tapers can be straight tapers like those shown in the illustration or they can be compound tapers in a convex or concave shape. Click for a discussion of Taper Design.
Next is the, usually level, Belly section of the fly line. This is the power conserving part of the line. It maintains much of the kinetic energy in the leading edge of the loop. It is the portion of the line that enables the line to cut into the wind. The belly of the line can be of varied length. Longer bellied lines will usually allow more line to be carried out of the tip of the rod as well as make longer mends on the water. This in turn allows the caster to shoot more line.
A double taper line will usually not shoot as great an additional amount of line as a weight forward line because the WF has a thinner (lighter) running line to pull behind it.
After the belly is the Rear Taper. The rear taper is the transition from the belly to the running line (on weight forward lines) or rear tip (on double taper lines). Most lines have shorter rear tapers from 4-9 feet in length depending on their weight. This length is sufficient to allow for a smooth transition of energy to the head on shorter headed lines. Some specialty lines have longer rear tapers as much as 25 feet in length to allow for improved mending abilities and longer line carry. These long rear tapers can smooth out the transition when carrying greater lengths of line out of the rod tip.
The last element is the Running Line (this is not found on a Double Taper). The running line is of a smaller diameter and lighter weight than the head. This allows the head to cast farther because it does not have to drag along as much weight as the double taper would. The running line allows the caster to still have control of the line when stripping the fly in, with less chance of it slipping from the fingers than if it were the thin monofilament material you would find on a shooting head (Single Taper).
