Fitting's Black Box

CLUBFITTING's BLACK BOX is shaft fitting. It's because there are essentially an infinite number of technical choices available to the shaft engineer when designing a shaft. Shape, graphite fiber properties, supplemental fibers, and resins with fillers are the major materials factors to consider. Bending factors include where to have regions of stiffness, where to have regions of softer flex, resistance to twist (torque) and how to vary those regions, and linear distribution of weight are performance factors that determine shaft design. 

The complexity of design factors makes it difficult for most of us to understand how shafts influence the performance of a golf club. It means that most clubfitting choices are done by media descriptions that are probably a limited mixture of technical design information and a heavy dose of marketing goals. The problem is that media descriptions must necessarily cover a broad range of golfers and are not likely to fit most of us as individual golfers. Thus, while we might get the right shaft some ot the time when we buy a new club, it's likely the choices will not be a good fit most of the time. When performance doesn't match with expectation, then the whole club selection process seems like somewhat of a mystery. 

What can we do about it? Well, as clubfitters, we can analyze shaft properties that are accessible to measurement with professional tools. We have EI machines to measure stiffness, torque meaasruing instruments, deflection measuring intruments, and similar tools to gather basic information about shaft properties that matter most in clubfitting. It allows us to lift the cover on the black box and see what's inside. We can take some of the mystery out of clubfitting.

Short Game Clubs

IMPORTANCE OF THE SHORT GAME. About 2/3 of the shots in a typical round of golf are played from within 100 yards of the hole, and 2/3 of those shots are putts. A short chip, like a 3-foot putt, counts the same as a monster drive or a long fairway approach shot. From this perspective, it’s easy to understand the importance of the short game, but most golfers spend more time and money on getting a new driver than on a complete set of short game clubs. We think the priorities should be recosidered in favor of properly fit wedges and puutter. Not convinced? Then just ask yourself, how important is 2/3 of the game? It’s the essential key to lower scores.

WEDGE CONSIDERATIONS. Most wedge shots are made with partial swings that depend on feel and require finesse; with backspin being essential for holding longer shots on firm fast greens. Distance and trajectory control for most golfers will improve in response to subtle changes in length, weight, shaft flex, and sole design. If there’s more than a 6 degree gap between clubs, reconsider your short game set makeup. To improve feel, change to a shaft that matches your tempo. The wedges you select should match the playing conditions of your course. Custom grinds enhance control of your wedges to match any turf condition and overcome the limitations of off-the-rack stock clubs. 

CHIP SHOTS. The greenside chip shot is not the same as the short pitch shot and both are different than the medium to full wedge shot -- different swing techniques, different kinematic sequences. This part of the short game is where most golfers run into trouble. We think it's because they are being taught outdated swing techniques that just don't work well with today's turf conditions, groove rules, and ball technology. And golfers usually buy wedge brands, not wedge performance.

But most importantly, golfers don't practice with their wedges -- we don't consider banging away in the short game practice area with a small bucket of balls to be practice. There's a skill to effective short game practice that's every bit as important to learn as getting fit for the right wedges for your game. We recommend a dedicated wedge game fitting that includes learning effective stroke techniques to form the basis of getting the best wedge for your game. Learning how to practice will help too.

PUTTING. It's worth a few blog posts on its own. But we mention here for one basic reason. The quality of your wedge game has a huge influence on your putting. It's obvious when we write about it, but it helps to consider that if you can't chip the ball into the hole, then you need to get the ball one-putt close. 

BUYING WEDGES AND PUTTERS. It's the area of club purchasing that generally gets the least attention. Here is how we look at it. Putting is about 40 % and wedge shots are about 25 % of our game. Anyone can become great in these parts of the game with the right equipment, good technique, and effective practice. Anyone. Talent is learned. We can make up for drives and fairway shots that didn't live up to expectations by pitching or chipping the ball close to the hole and sinking it with one putt. Great wedges and a great putter will feel like they are an extension of your hands and forearms. They will fit perfectly because you had professional clubfitting, not because they were mass assembled and stacked in a big box rack. Let us know how we can help you.

Measure Flex: EI or CPM

MEASURING SHAFT FLEX. There is much more to understanding the flex of a shaft than just measuring how stiff it is at the grip end and assigning an arbitrary classification like L,A,R,S,X to define how it feels. It doesn't help that there are no industry standards, which means that one company's regular flex might be a stiff flex or a "senior" flex elsewhere. What's regular flex to me might not be regular flex to you, so what is regular flex anyway? Well, there are measurement methods available, but which ones to use and how to interpret the results are subject to controversy. It's not surprising.

It helps to think about what flex actually means for a shaft. If you read my post on how shafts are made, it's clear that flex can vary throughout the length of the shaft depending on how it's made, and that the shaft designer can engineer specifc regions of flex along the shaft that respond differently to the complex forces generated during a golf swing. The way you measure flex -- I prefer to think of it as stiffness -- will influence your concept of what's important. A simple technique like frequency (cpm) measurement may get you to thinking that the tip and the butt regions are the key to understanding shaft stiffness. But if you use EI measurements you will see that the mid regions of a shaft might be where the most critical action occurs. Read the discussion below, look at the data from measuring the same shafts by both methods, then draw your own conclusions. Or better yet, send us an email and let us know what's important to you in shaft selection.

We'll save the discussion of how torque -- the resistance to rotational forces (twisting) -- fits into the picture for another blog post. Suffice it to say that it's another essential factor in understanding how shafts feel and perform.

EI STIFFNESS ANALYSIS. (E-I curves). A useful indicator of stiffness along a shaft’s length is EI, where E is a function of a material’s elastic stress/strain and I is a function of shaft wall thickness and diameter. These considerations are fundamental to the design of nearly all shafts in production today. We measure shaft EI with our own equipment. For Ei analysis, displacement pressure by a constant weight is measured along the shaft length in one-inch increments to reveal local stiffness variations that are engineered into the shaft. Variations in stiffness affect how a shaft will load in response to the changing forces that occur during a golf swing. EI analysis reveals essential details of flex design that help identify the best shaft for individual swing styles. 

FREQUENCY ANALYSIS. (cpm curves). CPM frequency curves extend the L,A,R,S,X flex classification through the length of the shaft, and they are used in comparison fitting methods. To generate a cpm curve, a shaft is clamped at different positions (usually at 5-inch intervals) along the length of the shaft and a constant 454 g weight is clamped to the tip. The tip is displaced and released, and shaft oscillation in cpm is measured by a strain gauge frequency analyzer. The oscillation frequency in cpm at each point reflects the average stiffness over the length of the shaft beam from clamp to tip. When the clamp is placed at the butt, frequency measurement yields the average flex that includes all regions of the shaft. For reliable data, discontinuous pneumatic clamps are highly recommended.

How Shafts are Made

GRAPHITE SHAFTS are constructed from 10 - 20 layers (sheets) or more of carbon fibers impregnated with specialized resins and supplementary compounds. These “pre-preg” sheets can be cut into strips and patterns then overlayed according to a unique pattern on a tapered rod (mandrel) that gives the shaft its final shape. Graphite fiber sheets of different grades can be intermixed with layers of different materials and thickness to strengthen or soften in predictable ways. Exotic (translation: expensive) materials like zylon and boron are examples of fibers that soften or firm the feel of a shaft.

The composition of resins used to hold the graphite sheets together can be varied and specialized fillers (e.g., nanotubes) can be added to help achieve a specific feel. After the graphite sheets are impregnated with resins and wrapped around the mandrel, they are baked in an oven then smoothed by a sanding process to yield shaft tubes ready for a lacquer finish, graphics, and testing.

The shaft engineer has unlimited design options to meet a distinct performance goal. It’s why shafts can have widely different bending properties that should be fit to the mechanics of your swing. We think of most OEM factory stock shafts as place-holders for the club head and grip that are waiting for custom work by your clubfitter. Unless, of course, you have your custom clubs built from the ground up. And in case you wondered, steel shafts have more than a few design options too, but that's a topic for another post.

Putter Buying Mistakes

BUYING A PUTTER. We think buying a putter should get more attention then buying the irons, driver, fairway woods, or hybrids. Here's why. Putting acounts for about 40% of the swings in a round. Putting is the great equalizer in the game: any player can become good at it. Good putting can help make up for difficulties in getting to the green. Good putting lowers your score, and you remember a low score long after the details of the round fade away. The right putter for you will increase your confidence to make putts, and the game becomes a whole lot more enjoyable and satisfying. We think you should consider the following points to avoid common buying mistakes. 

A traditional length putter should complement your address position, and act and feel like an extension of your forearms. An effective address position is essential in fitting for a putter. 

Anchoring the putter against your body, either at the belly or higher, requires careful attention to length, weight, and stroke mechanics to get the benefit of this equipment design. 

The better your stroke mechanics, the more likely you can be fit with a putter that improves your consistency. The putter should match your putting style.

Knowing the way you see the ball and the target line is an essential step in developing accuracy, but doing the appropriate tests to measure your "putting" vision is largely ignored by nearly everyone. We find it's a key step in putter fitting and in learning efficient stroke technique.

The mental side of putting has attracted plenty of "gurus" and teaching styles. There are simple guidelines to help you sort through this maze, but most importantly we find the mental game improves considerably when you have a correctly fit putter in your hands.  The keys to the mental game are developing confidence and learning how to focus.

Schedule a putter fitting with JTClubs and let us know how we can help you.