Common Cents Glossary
Following are terms and definitions that you may find helpful when reading or using the Common Cents System. Some of the terms here are unique to the system, while others are generic and/or common terms used in the vocabulary of rod building.
Where most of the initial flex in a rod blank takes place. "Fast Action" rods will flex mostly in the upper 1/3rd of their length. "Moderate Action" rods in the upper 1/2 of their length. "Slow Action" rods flex along their entire length. *See also "Progressive Action." The action of a rod is independent of the material it is made from.
AA / Action Angle
A relative measurement of rod or blank action. Originated with the Common Cents System.
BIG / Bending Index Graph
A plot relating the ERN and AA of a flyrod as a function of the distance from its tip.
¢ / Centsitivity
A measure of the sensitivity of a rod tip to observable deformation. The mass required to deflect a horizontally held rod tip a distance of two inches or 50 mm. Value can be expressed in units of ¢ or grams.
Unit of mass utilized in the CCS, composed of a common U.S. one cent piece minted after the year 1996. Each of which has the mass of 38.61 grains or 2.50 grams.
CCF / Common Cents Frequency
The frequency of a fly rod + line combination as measured by the procedure defined by the CCS.
CCS / Common Cents System
A complete system for taking relative measurements of the action and intrinsic power of rods and blanks. Also can be used to correctly match the correct casting lure or fly line weight to any rod.
Damp / Damping / Damps
Any system which, when set in motion, creates a force which inhibits that same motion, is said to exhibit damping. Damping forces are usually created by friction, either aerodynamic (external) or material (internal). *(Most true damping with regard to fishing rods is caused by air friction. Some internal material friction does exist, however.) Although most often incorrectly used within the confines of rod building, the term is generally used and understood to describe how long a rod takes to return to straight or stop, after being cast or flexed, i.e "This rod damps quickly."
_ / Delta
The difference between the ERN and the ELN, determined by the expression: Delta = ERN - ELN
DBI / Defined Bending Index
Part of the Common Cents System. Provides a quick reference to the Effective Rod Number and Action Angle (ERN/AA)
ERN / Effective Rod Number
Part of the Common Cents System which provides a relative measure of intrinsic power of a rod. A measure of the force required to load (deflect) the tip of a rod a distance equal to one third of its length.
ELN / Effective Line Number
Part of the Common Cents System which provides a measure of the mass of a fly line.
Normally used to describe a rod with a very fast action. A rod with a powerful butt section and a much softer tip.
IP / Intrinsic Power
See ERN. Also expressed in units of grains in accordance with the conversion tables of the Rosetta Stone,
With regard to the fibers used to make fishing rods, "Modulus of Elasticity," refers to the relationship between stress and strain. In more simple terms relative to rod building, it usually defines the stiffness to weight ratio of the fibers used to construct the rod blank. Generally speaking, the higher the modulus of the fiber used to make the blank, the lighter the resulting blank can be for any given stiffness.
Generally used to describe a rod or blank's stiffness or resistance to bending. See Tip Power, Power Reservoir, Intrinsic Power
A measure of the force required to deflect a rod a distance equal to one half of the rod’s length.
Term used to describe a rod blank that continues to bend farther back towards the butt end as load upon it is increased. As the load is increased, the blank responds by shifting the load onto the larger, more powerful area towards the middle and rear of the blank.
The basic table of the CCS which correlate AFTMA line numbers with line mass, ELN, DBI, IP, ERN, and common cents.
Within the confines of rod building it is generally used to define the rate of response and/or recovery of a rod. Otherwise, velocity.
Name for the type rods commonly used on the river Spey going back some 150 years. Today Spey Rods are generally regarded as any of the longer (11' to 15') two-handed fly rod types that allow long casts without the necessity of making a back cast.
Or "Effective Spine" is an effect created by several manufacturing anomalies. The result is that the rod blank will favor bending along a particular axis when load is applied.
The amount of material deformation when stressed.
Most often used to describe the durability of a rod or blank. The ability to withstand impact or stress.
The condition of a material when subjected to a force or load.
TP / Tip Power
A measure of the power of the tip of a rod as defined by the CCS.
WL / Weight of Line
The mass, measured in grains, of a fly line required to deflect a fly rod a distance equal to one third of its length in accordance with the CCS.
Additional rod building terms can be found in the online glossary at www.rodbuilding.org