Length

What it is and Why we care

• The height and swing plane of the golfer.
• The length the golfer can "handle", and still make reliable contact.

• A longer club will hit the ball further for some golfers, up to some point of diminishing returns. This is a benefit of length.

  The factors of length that affect distance include:

  • If a longer club can be swung at the same angular speed as a shorter one, then the clubhead speed will be greater with the longer one. The speeds will be in the same proportion as the lengths. But this depends on being able to maintain the same angular speed, which is hardly guaranteed. This has been studied in detail elsewhere. In order to increase the likelihood that you can maintain angular speed...

  • Use lighter components, so you're not putting on "swingweight". We'll better quantify this in a subsequent chapter. For now, let's just say that if you keep the swingweight constant as you lengthen the club, you will likely see longer shots. You can only do this by selecting lighter clubheads and/or shafts, because swingweight increases with length if the components are not lighter.
  • If you simply lengthen the club with the same components, the swingweight will increase. This may still give you longer drives; it depends strongly on how you swing the club. A smooth "swinger" may not gain any distance at all from a longer club. A less-smooth "hitter" may pick up some distance. (I've done some mathematical analysis that predicts this. Experiments reported in Golfsmith's Clubmaker magazine confirm it.)
  • Of course, accuracy is an issue. If you can't hit the ball squarely with the longer club, you may actually lose distance. 

• A longer club will be less accurate beyond some point. This is a problem with length.

  It is harder to put the ball in the middle of the sweet spot as you have to stand further from the ball and swing a longer tool at it. This is less serious for a driver, which is normally used only if the ball is sitting up on a tee, than for the other clubs. Where a swing must be precise in order to hit the ball cleanly, the clubmaker should think twice before adding length unnecessarily. The approach of Player and Woosnam, and the 48-inch driver of Rocky Thompson, may work for an experienced professional but can produce very erratic results for a novice.

• A longer club plays as if its lie is more upright. (Actually, it causes a flatter swing plane for the same lie.) We'll cover this aspect in the section on lie angle.

• A longer club feels more head-heavy. We'll cover this aspect in the section on swingweight.

• Length interacts in a complex way with flex. We'll cover this aspect in the section on flex.

So ultimately, a proper club length is one that is as long as the golfer can consistently hit in the longer clubs (to maximize distance). This must be balanced with the need to get a proper lie angle, swingweight, and flex, all of which are also affected by length.

Measuring Length

Originally, the length of a club was defined as the distance from the butt of the club to the point where the shaft (or its extension) intersects the base of the sole. Frankly, I have a lot of trouble with using this as a working definition, because:

To be useful, length must somehow be related to the sole right under the "sweet spot", because that's where the club strikes the ground. Because clubheads vary markedly in their "camber" or "rocker" (the curve of the sole), the intersection of the shaft and the sole may be right near the ground or considerably above it. Consider the accompanying diagram: For the no-rocker sole, the intersection of shaft and sole is right on the ground. But for the high-rocker sole, the intersection is considerably above the ground. So the high-rocker sole is a shorter club by definition, even though it plays at effectively the same length.

Still looking at history and tradition, there is a practical problem even measuring a club by this definition. The measurement called for was down the axis of the shaft. But you can't really measure that, only estimate it, because you can't run a ruler down inside the shaft and out throught the bottom of the hosel. So a more reasonable, more practical, and more modern definition is the distance from the butt: ... to the point where the shaft would meets the ground, if the club were soled in a normal address and the shaft were extended to the ground. ... measured along the back of the shaft and the heel of the clubhead, rather than down the axis of the shaft. The major clubmaking suppliers offer devices that make it easy to measure a club using this definition. They consist of a ruler with a hinged straightedge at the "0" end. Lay the club along the ruler with the sole against the hinged straightedge. Adust the straightedge so it is parallel to the grooves. Now the edge of the butt indicates the length of the club on the ruler.

The USGA and R&A made one more modification to this measurement, that has made measurement tools less expensive and easier to use as well as discouraging a form of "rule-beating". (Think of that as cheating without actually breaking the rules.) They specified that, whatever the actual lie angle of the club, the length would be measured with the shaft at a 60° angle to the ground. This removes the need for a hinge for the straightedge, and the need to match the angle of the straightedge to the grooves. Easier -- and only different from the former definition by an eighth of an inch or less. I have an article with more details on this measurement.