Golf Club Specs: Torque
Here’s one for the folks who fiddle with their clubs in the garage, the home-schooled golf engineers. One of the facts about golf shafts that you should understand is that of “torque.” This, however, is a slight misnomer since what the shaft manufacturers are really telling you is the shaft’s torque reading.
That’s because torque is the force that is applied to the shaft causing the shaft to twist along its longitudinal axis. But for the sake of simplicity, I’ll refer to the torque reading as torque. Torque, basically, is the measurement of force used to twist or to stop something from twisting, like a golf clubhead or shaft.
You know, like trying to wrench free a rusted bolt.
Let me give you an example of golf shaft torque: Hold your driver firmly by the grip (butt-end) and then grab the club head (tip-end) and twist the club face open, but do not let the grip end move. You’ll see a slight rotational movement of the face. This is a result of the applied torque that you are putting on the shaft.
A rather simple example that will clearly show the effect of torque on a tubular object (which a golf shaft is) would be to use a straw. Next time you buy a milkshake get an extra straw. Hold the straw horizontally with your fingertips on both ends. Now gently rotate your fingertips in opposite directions. You have applied torque to the straw. You’ll see the length of the straw’s body twist.
In years past, the torque of a golf shaft was measured by clamping the butt-end securely in a fixture so it would not move. The tip-end would have a perpendicular 1-foot-long lever attached to it and a 1-pound weight would be hung at the end of the lever. The weight would create a force to twist the shaft “1-foot pound.”
The amount of twist seen in the shaft would be measured in degrees. Now days there are computer controlled machines that calculate the torque very quickly. A golf shaft (say for a driver) with lower torque will have a reading of 3 degrees, whereas one with more torque would be 5 degrees.
The higher the number, the more twist or torque a shaft has. When you swing a driver at full speed, you are exerting many forces on the shaft. Longitudinal bend (flex) and torque are just two of them.
The shaft’s body is not only bending from the force, it also is twisting. The shaft’s tip section would rotate or torque even more if a golf ball was not hit on the exact center of gravity (sweet spot) on the clubface.
So, why do we care about a shaft’s torque? For many years when golfers used steel shafts in their drivers, the torque readings were around 2.5 degrees. This was the accepted amount of twist for a shaft and was preferred by the better players. When graphite composite shafts first came on the market their torque was generally higher than steel shafts and better players did not consider them as accurate since the shots tended to spray off-line due to the higher degree of rotation.
As design and manufacturing methods improved, graphite shafts were soon able to hit all sorts of different torque readings including very low readings of below 2 degrees. As it turned out, only a very strong swinger of the club could handle the stiff, harsh feel of these very low-torque shafts.
Even PGA Tour players preferred the 2.5- to 3-degree range. Slower swingers actually preferred a little higher torque, since that design usually produced a higher launch angle and better feel at a slower speed.
Remember, a 240-yard drive that is a few degrees off-line will not be as big a problem as one hit a few degrees off-line at 300 yards.