Set Makeup

So now we've found the maximum and minimum length irons the golfer can hit at all consistently, and perhaps the maximum length wood as well. How do we translate this into a set of lengths for the clubs the golfer needs?

In this section, I'll deal with choosing a set makeup for the irons. The woods can follow in this spirit, but more likely should be fit individually and experimentally. Note that there are fewer woods than irons in most sets, and they are used more "individually", rather than in a simple progression of intended distance. (E.g.- tee club, fairway club, trouble wood.)

The first step in fitting the irons is to relate the maximum and minimum lengths to the "standard" lengths for the irons. Assume that the clubs will differ by 1/2" from one to the next, and see what the total difference will be over the set. For instance, a conventional set from 3-iron to 9-iron has 6 gaps, so the set "needs" a 3" difference from 3-iron to 9-iron.
(That's 6 times 1/2", or 3 inches.)

If the golfer's "comfort zone" is three inches wide (or more, if the set will contain more irons), then you're set. Make the set for a 1/2" difference from club to club. Choose the actual lengths within the range from the following considerations:

  • Choose the length that results in proper lie angle with the clubheads you intend to use. (If you can bend the clubheads, this is less of an issue.)
  • Choose the longer end of the range for distance, or if the golfer likes a heavier swingweight.
  • Choose the shorter end of the range for accuracy or consistency, or if the golfer likes a lighter swingweight.

Note that I didn't suggest spreading the gap between clubs to use the whole range, if the range is bigger than a 1/2" gap would fill. That's because every set of iron heads on the market is "sequenced" assuming a 1/2" spacing. The if you depart from this spacing, you will have to do something special about swingweight and lie angle; you can't just use the heads as they arrive. If you can't "fill up" the range, just smile. You're left with a few happy options:

  • Most golfers will do better over a smaller portion of the range, anyway.
  • If the golfer is more skilled and wants to use the whole range, you can use the additional lengths by adding irons at the high end (2-iron, 1-iron) or the low end (more wedges).

Non-Standard Length Sets

But suppose the range turns out to be narrower than 1/2" times the number of gaps in the intended set. You have two options:

Go with fewer clubs. Don't dismiss this out of hand. A narrow range generally indicates a less-skilled golfer. Removing long irons is generally the best prescription for improving a golf score.

Unfortunately, many golfers' egos don't deal well with this suggestion. There is a "Plan B".

Go with narrower gaps than 1/2". This can be made to work, but it requires more work than just cutting the lengths closer together.

  • The clubs must be bent for lie angle, because most sets as sold assume that the length increment will be 1/2".
  • Something must be done about swingweight, because most sets as sold assume that the length increment will be 1/2".
  • Flex must be tuned to the narrower increment, because most shafts as sold assume that the length increment will be 1/2".

A word about the swingweight. The first 20% of narrowing the range (down to a .4" increment) could be justified on the basis of moving from a swingweight-matched set to a moment-of-inertia-matched set. After that, you will have to deal with the fact that the long irons are relatively lighter and the short irons relatively heavier, due to the difference in length. You will either have to modify the heads or "live with it".

Constant-length irons

For comparison purposes, here is the difference between a "standard" (half-inch increment) set and a completely constant-length set of irons. I have used Max Dupilka's "Trajectory" program to calculate the carry distances for a normal (half-inch) set and a constant-length set.

The range is compressed a bit, compared with a normal set, but not a lot. (105-171 yards, compared with 103-177 yards.) But that's not the big difference. The constant-length set has a swingweight difference of TWENTY POINTS between the 3-iron (lightest) and the 9-iron (heaviest). The distance curves assume the customer can properly swing a set with that big a difference. I have factored in the distance vs. head weight curves from Cochran and Stobbs; it reflects the fact that the lighter 3-iron will be swung faster. But those curves come from golfers skilled enough to hit a very wide range of swingweights. Remember though, we wouldn't be talking about making a set like this for highly skilled golfers, would we?

More recently, clubheads have been introduced with constant weights across the set -- specifically intended to be used in constant-length sets. I have repeated the study with this assumption.

Other Length-Related Effects

You can increase or decrease length, but not without affect the other whole-club characteristics. We'll see this in detail in the following chapters, but here's a preview:
  • Swing Plane and Lie Angle are affected directly, and in a big way. The angle of the club at impact is necessarily related to the swing plane, as we'll see in the next section. For now, let's just say that the longer the club relative to the golfer, the flatter the swing plane and the flatter the lie angle. This can be good or bad. Consider a few examples:

    • A very tall long-time golfer has learned to cope with "normal" clubs by developing a very upright swing plane. He finally goes for custom clubs, and the clubmaker uses the "rule of thumb" to make him a set with standard lies and a correspondingly greater length. The golfer will have to re-learn the swing on a new plane. It would have been better for the golfer, the clubmaker, and a good teaching pro to decide in advance what swing plane (and, by implication, what length and lie) would be a good compromise between "classic" and what he already knows. This would probably result in a set somewhat longer and somewhat more upright than "standard".
    • A relatively short, athletic woman with a strong swing finds that clubs sold as "women's clubs" are too short and light for her. She needs the increased resistance of a higher swingweight, and can make use of it to increase her distance. (She also wants a stiffer shaft, but we'll save that for another chapter.) It's clear in this case that the clubmaker wants to go long, and make up for it with a flatter lie.

      I chose a woman for the example, because on average women are shorter than men; that has led to some assumptions about "women's clubs" that are unwarranted except in the average. But anyone who has taken a good look at Gary Player or Ian Woosnam (two short male pros) swing a club now knows where their distance comes from.

  • Swingweight increases by about 6 points for each inch of increased length. We'll learn in a following chapter what this means. For the time being, let's just say it will make a big difference in the way the club hefts, and something of a difference in the way it swings.
  • Flex may be effectively stiffened by shortening the club. All other things being equal, the club will vibrate faster if it is shorter. Whether you consider this stiffer depends on:
    • How you lengthen the club, by trimming at the tip or the butt.
    • What theory you subscribe to relating frequency to stiffness. (There are several competing theories, as we shall see.)
So you can't select length in a vaccuum. It is important to fit the golfer with the correct length clubs, but every change in length requires revisiting several other aspects of the design.

Last modified Aug 26, 2007