V. Shafts
It is generally agreed that the shaft is the single most important part of the golf club. Shaft selection involves many variables including material, length, torque, kickpoint (bendpoint) and most importantly, flex. Having properly fitted shafts in your clubs is probably the best thing you can do with regard to equipment for improving your game.
1. Steel
Steel shafts are generally made from carbon steel or stainless steel. For the most part, the manufacturing processes between the two are similar. A steel strip is rolled into a tube and is drawn over a mandrel until the diameter and wall thickness are reduced to their exact specifications. At this point the step pattern is formed on the shaft. Then the walls are made thinner at the grip and thicker at the tip to give the shaft its flex characteristics. Then it is hardened, tempered, straightened and stress relieved. The final step is to polish and chrome plate the shaft. One of the best features of the steel shaft is the ability to have the same feel throughout the entire set. This means that the shaft stiffness of the 3 iron will feel the same as the 9 iron, if they are properly assembled. Other features are its durability and price. Steel is the preferred material for the majority of the players on the US and European PGA Tours.
2. Graphite
Graphite shafts are made from a graphite tape or sheets. The material, which has an epoxy binder, is wrapped around a steel mandrel. The wrapped shaft is then temperature cured and the mandrel removed. The raw shaft is then sanded and cut to proper length, at which point it receives a clear or colored paint coating. Its most notable feature is its lightweight. It also helps dampen the vibration caused by clubhead impact with the ground. A few of the drawbacks are the feel of the shaft (some people complain that a stiff graphite shaft does not feel like a stiff steel shaft); the stiffness may not be consistent throughout a set, and its price tag. A newer manufacturing process called "filament winding" can produce a set with greater consistency, but at a higher price. Graphite has gained significant acceptance on the US LPGA Tour and the US Senior PGA Tour.
3. Titanium/Aluminum
I have very little information regarding the titanium and aluminum shafts and their respective manufacturing processes. There are not many titanium or aluminum shafts on the market and to my knowledge, none are in use on any professional tour.
4. Flex
The stiffness, flex, or deflection of a shaft defines the bending characteristics of the tube, when a load is applied to the shaft. The most common shaft flexes are designated as X (extra-stiff), S (stiff), R (regular), A (man's flexible), or L (ladies'). Typically, a faster swing speed will benefit from increased accuracy with a stiffer shaft. A slower swing speed will benefit from increased distance with a more flexible shaft. Flex is probably the single most important factor in the feel of a shaft.
5. Frequency/Slope
Some manufacturers rate the stiffness of their shafts according to the Brunswick Slope. This measurement assigns a stiffness rating to a shaft according its frequency or how fast it vibrates and is also dependent on club length. This frequency is expressed in "cycles per minute" or CPM. Below is a comparison of CPM, slope and standard flex for a 38 inch club (typical men's 5 iron).
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6. Torque
Generally torque is a rating applied to a graphite shaft. It specifies the twisting characteristics of the shaft. The normal torque rating of a steel shaft for woods is about 2.5 degrees and 1.7 degrees for the irons. The general range of torque ratings found on graphite shafts are from 3.5 to 5.5 degrees, although it is possible to get shafts with lower or higher ratings. The higher the torque rating, the more the shaft twists for a given twisting force. The torque rating also seems to be tied to the stiffness of a shaft, the lower the torque rating, the stiffer the shaft. There is no accepted industry standard for measuring torque.
7. Kickpoint
The kickpoint (a.k.a. bendpoint or flexpoint) defines where the shaft will bend. Kickpoint affects the trajectory of the shot, the higher the kickpoint, the lower the trajectory. (A high kickpoint is closer to the grip end of the shaft; a low kickpoint is closer to the head end of the shaft.) The effect in trajectory is small but measurable. For someone that generally hits the ball with a high shot trajectory, a high kickpoint is desirable in a shaft. For someone with a low shot trajectory, a low kickpoint helps get the ball airborne and on a higher flight path. The kickpoint also affects the feel of the shaft. A golfer who can feel the difference finds the high bend point makes the shaft feel like "one piece", while with the low bend point, the shaft feels as though the tip whips the clubhead through the ball. There is no accepted industry standard for measuring kickpoint.
8. Spines
A shaft is considered to have a spine when its flex and torque characteristics vary with its orientation. Since all shafts, regardless of material or manufacturing process, have some variation, all shafts are considered to have spines. Until very recently, the USGA rules for shafts specifically required shafts to have the same characteristics, regardless of orientation. However, variations are an inevitable outcome of the manufacturing processes and the USGA has finally acknowledged this fact. New guidelines from the USGA allow clubmakers to align shafts so that they are consistent from one club to the next within a set.There have been some studies that indicate improved shot consistency when shafts are aligned throughout a set. Some professional players have been aligning their shafts for many years and it is now becoming more common in the mass market. For an additional fee, some shaft vendors and manufacturers will now sell shafts with the spines marked. There are also devices available to custom clubmakers which will allow them to determine spine orientation.
9. Notes
Never base your shaft selection on specifications, always try to demo the shafts you are considering. This is because there are no industry standards for measuring flex, kickpoint or torque. One company's low torque extra stiff shaft may be another company's mid torque regular flex shaft. Choosing the material, flex, and kickpoint of a shaft will depend entirely on what feels right when you swing the club. Someone with a high swing speed may choose a steel shaft with a flex rating of X and a low kickpoint, while someone with the same swing speed may choose a graphite shaft with a flex rating of R and a high kickpoint. The general consensus is see your local professional and ask what he/she recommends. Make your decision from there.
This FAQ is Copyright 1999-2002 by Daniel J. Driscoll, all rights reserved. Product and company names used in this document may be trademarked or copyrighted by the respective owners. This document may be replicated in whole or in part, without alteration. All replications must include this copyright notice.
