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Golf Equipment Chronicles 2006 (Part 5)

A Brief History of Shaft Fitting (including Recent Discoveries)

There was a time, long ago, when shaft fitting was simple. All able-bodied male golfers between the ages of 15 and 65 played stiff flex shafts. Only invalids and ancients played regular flex. Women and kids played sawed-off hand-me-downs. No one worried about shaft flex.

The Paul brothers founded Golfsmith in the late ‘60s. That gave rise to a new trade: “custom clubmaker.” Custom golf clubs became popular and the industry grew rapidly. By the early ‘90s Golfsmith was joined by Golfworks and Dynacraft and a host of smaller distributors providing shafts, heads and supplies to the custom clubmaker community.

The rise in custom clubmaking focused attention on fitting golf clubs to match a player’s swing. Clubmakers began to offer custom shaft fitting services.

Fitting by Swing Speed

In the early ‘90s the major distributors developed shaft testing protocols that recommended ladies, senior, regular, stiff or extra stiff shafts based on swingspeed. New technology -- inexpensive electronic devices to measure swing speed -- became available. Determining shaft specifications from catalog charts was a crude fitting method but better than pure chance. Through experience, most clubmakers devised their own fitting methodologies. For many, a 90 MPH swing speed with a driver indicated regular flex, 100 MPH a stiff flex and 110 MPH an extra stiff flex. Clubmakers with playing experience and a good eye modified their flex recommendations based on tempo. A fast tempo brought a slightly stiffer recommendation and a slow tempo got a more flexible recommendation. For most clubmakers, measuring tempo was difficult.

Through the late ‘90s, there wasn’t much chance to “fine tune” a shaft fitting. Shafts came in five stock flexes, (L, A, R, S, X), but most able bodied men still chose “stiff.” Old habits die hard.

Experienced clubmakers noticed that some players did well with a stiff flex in one shaft model but a regular flex in another. The obvious conclusion was that there was a great deal of difference in the way manufacturers established their flex designations and the way different shaft models performed in play. Irregularities in the playing characteristics among different shaft models led to endless consternation for golfers trying to figure out what shaft best suited his swing. Clubmakers usually recommended a narrow range of shafts - calling on personal experience and satisfied customers to build confidence.

Until the late ‘90s, shaft fitting was still basically “trial and error.”

Fitting by Frequency Matching

Royal Precision invented “frequency matching” in 1974 to help sell their shafts. Frequency matched sets appeared on the market through the ‘80s and ‘90s from manufacturers searching for a technical edge. The concept might have been a little too technical for the times and golfers never picked up on frequency matching. True Temper continued to dominate the shaft business. The Royal Precision electronic device for measuring frequency was expensive so the technology did not catch on with clubmakers either.

By the late ‘90s new companies offered inexpensive electronic frequency meters. About that time, some clubmakers intent on matching the right shaft to a player’s swing felt a need to create their own flex designations, based on their experience. The search for precision in shaft fitting lead to determining “true” shaft flex by measuring frequency. Today, frequency meters are a universal appliance in custom golf shops.

Testing the frequency of a shaft requires clamping the butt end in a vise and oscillating the shaft with a tip weight or the actual club head installed. The oscillations are measured by a meter and expressed in “cycles per minute” or CPM. The faster the oscillations, the stiffer the shaft. Results are plotted on a “slope chart” which converts the CPM reading to a flex value. Flex values are expressed in decimal form from 2.0 to 8.0 to a tenth of a degree. Royal Precision introduced extreme granularity to the interpretation of flex. Rather than five flexes, there are now sixty. Overkill, to be sure.

Alas, with the proliferation in frequency systems there was no agreed standard either for measuring cycles per minute or interpreting the readings. All of the systems were different. The meters were based on different technologies. Some vises utilized three inch jaws, some five inch, some seven inch. Some clubmakers tested shafts with grips on, some with grips off. Different tip weights were used. The result is that CPM readings between systems were “apples and oranges.”

That problem was confronted and solved by a Professional Clubmakers’ Society (PCS) task force, culminating in the release of the “Equalizer” system in 2001. The PCS Equalizer was based on a calibrated shaft and customized Excel spreadsheet that normalized the interpretation of flex among incompatible systems. Each clubmaker who standardized his interpretation of flex based on the Equalizer could exactly match the flex of another clubmaker using the Equalizer, even if their frequency meters, vises and methods were different. The Equalizer co-opted the Royal Precision nomenclature for interpreting its flex values. In the Equalizer system, a regular flex was 4.5, stiff flex 5.5 and extra stiff flex was 6.5.

Although the Professional Clubmakers’ Society promoted a standard interpretation of flex, the PCS was out of synch with the Royal Precision system, perpetuating the confusion about interpreting flex. The difference was approximately fifteen cycles. Fifteen cycles is over a full flex, a nontrivial discrepancy. Clubmakers tend to pledge allegiance to either the PCS or Royal Precision. As a result, two professional clubmakers from different camps, fitting by frequency, can give recommendations that differ by over a full flex. Golfers who want to know for sure the frequency matching system that works best for them will have to find that out for themselves through testing. Fortunately, new technology makes that testing reliable, if tedious.

Limitations of Interpreting Flex by Frequency

Measuring frequency by clamping the butt end of the shaft and then “twanging” only tells part of the story about shaft flex. The area of the shaft that flexes with this test is the butt section, roughly 14” from the end of the shaft. The standard CPM reading is the butt flex measurement. Just about the time that fitting shafts by frequency became common among all clubmakers, those clubmakers with lengthy experience fitting by frequency began to discover the limitations of fitting by frequency alone. It would be great if there were a linear relationship between swing speed and shaft flex. Alas, shaft fitting is not that simple.

Certain shaft models that test very stiff in butt frequency readings are nevertheless easy to play by golfers with average swing speeds. The Graphite Design YS-6 series for woods and Rifle Lite iron shafts are notable examples. Such shafts are described as “butt stiff and tip soft.” Conversely, shafts that tested soft were found to play very well by high swing speed players. The Fujikura Banzai is an example. Such shafts are described as “butt soft and tip stiff.” Some clubmakers went as far as to assert that “frequency doesn’t matter.”

To better understand the problem, some clubmakers began to test frequency at points along the entire length of the shaft, an operation that became known as “zone profiling.” The goal was to produce a graph of “bend profile” of the shaft that could be compared, shaft to shaft to understand playability characteristics. The first attempts to make sense of zone profiling failed due to confusing methodology. But by 2004, the methodology was worked out. The problem was solved by adopting a heavier standard tip weight to slow down the CPM reading near the tip section of a shaft.

Hot Stix Technologies headquartered in Scottsdale, AZ tested hundreds of shafts with a slightly different methodology, applying a measured force at points along the length of the shaft to produce a proprietary bend profile which they call the “EI Curve.” The resulting graph is similar to the graphs produced by zone profiling using the zone frequency testing method. Hot Stix added another step to their protocol, testing torque. Hot Stix has the largest database of shaft data in the industry. Hot Stix’ ultimate goal? Automate the process of shaft fitting and club fitting for golfers. They licensed their technology to clubmakers for shaft fitting. They also licensed their technology to Golfsmith to help standardize club fitting in the superstore environment.

In the winter of 2005, a Professional Clubmaking Society member is working on a similar shaft profile database that will be marketed by the PCS when it is complete. Other companies are working on ambitious projects, all aimed at understanding the way a shaft flexes and torques during the swing to better fit players. Progress has been made, but there is still a long way to go before any of the systems will produce perfect fitting recommendations with 100% accuracy.

Launch Monitor Technology

By 2002, a new tool became widely available to clubmakers. Launch monitor technology changed the focus of shaft fitting from what the player was doing, to what the ball was doing.

The major manufacturers have spent millions of dollars to build launch monitors to test and fit their Tour players and well-heeled amateurs. For the most part, they kept their inventions proprietary. A few private companies attempted to develop launch monitor technology to market to less advantaged manufacturers and independent clubmakers. Mitch Voges of Max Out Golf Labs in Los Angeles was an early believer in the value of launch monitor technology. The Max Out launch monitor was based on high speed photography to snap a couple of pictures of a ball a couple of microseconds after impact. Privately funded, the development effort took several years. In the meantime, Swing Dynamics brought a launch monitor based on Max Out designs to the market, survived for a while but went out of business in 2005. The Max Out launch monitor is now in use at three Max Out Golf affiliates including the Golf Lab in Palo Alto. The Swing Dynamics launch monitor sold for $15,000. The Max Out version is not for sale. There are a few other players in the launch monitor business.

Focaltron Corporation brought the Golf Achiever, based on laser technology, to market in 2001. The first release had a lot of problems, undermining confidence. The second model was a solid system for comparing the performance of golf clubs. The Achiever gives reliable data for ball speed and launch angle but is criticized for calculating spin rates. A Golf Achiever sells for $5000.

The Vector launch monitor is based on infrared photography. It is an inexpensive and very portable device. Because of those features, it has become the leading launch monitor in the industry. It is a very good unit, but not perfect. It can give unreliable distance readings, especially for indoor use. A Vector launch monitor sells for $4000.

The Flight Scope is marketed by a South African company. It is based on radar technology. It is reputed to be the most accurate system on the market for outdoor use. The Flight Scope sells for $14,000.

A pioneer company has been reconstituted to market another radar based launch monitor. The distance caddy was a ground-breaking device at $1500. The new Zelocity system sells for $4000.

The advantage of launch monitors is that players could compare the actual performance of golf clubs. A lot of attention has been focused on launch angle and spin rates. That is because most players care most about hitting the longest possible drives. Depending on the strength of the player and the efficiency of the player’s swing, there is a theoretically perfect launch angle and spin rate. The only way to find that combination is by testing with a launch monitor because the differences are not visible to the naked eye.

Launch monitor results are not perfect. Although great indicators of comparative performance, launch angle and spin rate alone do not tell the whole story. On-course testing is the only way to know for sure how a driver performs. But launch monitors make the tedious process of finding the right shaft, and the right head for that matter, much less time-consuming. Clubmakers are increasingly building out “fitting sets” with heads and shafts that are interchangeable. Fine tuning shaft selection becomes achievable if a clubmaker can “quick change” a soft tip shaft for a stiff tip to give a player a little less backspin.

Computerized Shaft Fitting

With the recent focus on using launch monitors to collect swing and ball flight data and the creation of databases with detailed shaft profiling characteristics, it is only a small step to “computerized fitting.”

Hot Stix Technologies is the current leader in computerized club and shaft fitting. In the Hot Stix system, a player’s shot data is recorded from a launch monitor. The swing data is then analyzed and a “perfect” golf club or shaft is recommended from the database.

Limitations of Computerized Shaft Fitting

The possibility of taking a few swings and then pressing a button to get the right club or shaft recommendation is an alluring promise, but far from perfect. In a computerized fitting, a player is asked whether he wants “distance or direction” -- “higher or lower trajectory” and other questions that custom clubmakers use to discover a player’s desired results. The answers to those questions are then matched against the shaft database. The result is a numerical value that is used to rank the possible shaft choices. The best choice might be a “9.1” the second best a “9.0” and so forth down the line.

With any numerical ranking, it is impossible to know whether the rankings reflect meaningful differences. As an example, it may be that a player who is searching for distance receives a recommendation ranking a dozen clubs. For that player, the computerized fitting program might rank one club above another if the projected distance is one extra foot. Those projections might have a “margin for error” of five yards. It is possible that the top ten recommendations from a computerized shaft fitting are, for practical purposes, identical as far as the player is concerned. Given the inconsistencies in any human being’s swing, it may be that all clubs within one or even two ranking points will perform almost the same in actual play.

Computerized club fitting is really a technology that is primarily aimed at speeding the sales process. For players who really want to know what recommendation fits them best, there is no substitute for taking the top four or five recommendations to the range or the golf course for the ultimate test. Computerized fitting definitely helps you winnow down the choices, but the idea that a computer is going to find the perfect club is a dream, if not an hallucination. Besides, all golfers know that the most important characteristic of a golf club is something that you can’t measure - that characteristic is “feel.”

Shaft Orientation

In the endless quest for perfection in shaft fitting, clubmakers began to realize that even with the correct length, weight and flex there were still inconsistencies in shaft performance. Strategic Shaft Technologies (SST), a Miami, Florida firm, developed a method to test the consistency of golf shafts and orient them in the most stable plane for insertion in a club.

SST instrumented operations to locate the “hard side” of a golf club and then find the best “plane of uniform repeatability.” The goal of the SST PURE ª system is to make all shafts in a players set feel and play consistently. Independent testing performed by Golfsmith confirms that SST PUREd clubs improve accuracy and average distance due to solid contact.

In the period between 2000 and 2005, most independent clubmakers began to perform some kind of shaft orientation prior to installation. It is now the consensus of most professional clubmakers that shaft orientation is an important step in the clubmaking process.

The Importance of Measuring Shaft Load

Starting in the mid ‘90s, True Temper marketed a shaft fitting device named the Shaft Lab. The idea was to measure shaft deflection during the swing, add some time sequence data and make a shaft flex recommendation. The Shaft Lab was very well received by the clubmakers who could afford the $7500 price. But the Shaft Lab was difficult to use, requiring a player to be wired. The Shaft Lab only recommended True Temper products. True Temper has not updated the Shaft Lab for several years and the system has fallen out of use.

Understanding the way a player “loads” (deflects) a shaft is probably the most important single piece of information in clubfitting. It is interesting to note that, with the exception of the Shaft Lab there has been little attention paid to this all-important characteristic - until now.

The most important breakthrough technology in 2005 is very likely to be the Max Out Golf Lab “Shaft Max” - shaft load measurement system. I’m defining “breakthrough technology” as a system that changes the way clubmakers determine their fitting recommendations. Until the Shaft Max, improvements in shaft fitting methodology were incremental, moving slowly through swingspeed, shaft flex, shaft profiling, shaft orientation and then testing the results with launch monitor data. In that evolution, there was nothing that radically changed the way shaft recommendations were made. With the Shaft Max, there are indeed radical differences in fitting recommendations.

In the month we have been using the Shaft Max at the Golf Lab, we have fitted several senior players who, by swingspeed, tested for “senior” flex. We fitted these senior players with “extra stiff” flex shafts with extraordinary results. Similarly, strapping young players with low handicaps - for all the world stiff or higher golfers - have been fitted with “regular” flex with good results. We have made fittings based on Shaft Max data that we would never have made by employing traditional fitting methods.

The Shaft Max System

The Shaft Max system is based on sensors installed in standard shafts. The system uses two common shafts, the True Temper S-300 and the Fujikura Vista Pro 70. The sensors are installed in the shaft horizontally and vertically. The horizontal sensor measures shaft deflection in the swing plane. The vertical sensor measures “toe droop.” The sensors are connected to a small transmitter that a player wears on his wrist. The Shaft Max system is wireless. There is no interference with a player’s swing.

The wrist transmitter sends shaft deflection and timing data to a computer. The computer records downswing time, maximum shaft deflection, an acceleration reading and, using this data, makes a shaft flex recommendation on a scale of 1 to 12. The system also draws a graph that becomes a “fingerprint” of a player’s swing. The system is quick, within three or four swings with a driver and six iron, all of the required data is collected.

The “Ideal” Golf Swing

“Maximum speed at the moment of impact” is a phrase that describes almost all “stick and ball sports” as Mitch Voges likes to refer to golf. If that is true, then a key element of a great golf swing is acceleration. The great golf swing stores power at the top of the backswing and then lets that power loose through gradual acceleration, building up to the moment of impact.

Inefficient golf swings let the power loose too soon with moves usually described as “coming over the top” or “early release.”

Reading the “Fingerprint”

Figure A Shaft Max graph shows a player with “picture perfect” shaft loading. Note how the top graph builds gradually to a peak and then releases. The bottom graph reflects significant “toe droop” at the moment of impact. The flex recommendation of 10, near the top end of the scale, suggests a very stiff flex is appropriate. The toe droop suggests a shaft with a stiff tip is required. This player would probably be fitted with Project X 6.0 or True Temper Dynamic Gold S-300 or X-100.

Figure B Shaft Max graph shows a player with a significant load reading but without great acceleration. This is a representation of the actual swing of a senior player with an average swing speed. Note that the elapsed time indicator shows a fast tempo, shaft deflection is significant and the flex recommendation at 8.0 is at the lower end of extra stiff. This senior player was fitted with 95 gram graphite shafts, _ inch shorter than standard at a PCS Equalizer 6.0 flex value.

Figure C Shaft Max graph shows a player with a rather mild load reading and medium acceleration. This is a representation of the actual swing of a young, low index player with a moderately high swing speed. Note the elapsed time indicator is at the high end of the range indicating a smooth but slow tempo. This player was fitted with True Temper Dynamic Gold R-300 shafts.

Figure D Shaft Max graph shows a player with a serious swing flaw. Note the “dip” in the top graph. This pattern indicates that the player is “losing pressure” as Mitch likes to describe a swing that actually loses speed during the downswing. After discussion and viewing videos of his swing, this player decided to take a few lessons before making any equipment changes.

Case study: “The Judge”

The Judge is 67 years old. He’s a lifetime competitive golfer. He still plays over 20 tournaments a year. The Judge went “game improvement” a few years ago, investing in a set of Callaways with graphite shafts. Over the years, he has been a Golf Lab regular, adopting a 48” driver over three years ago. He was an early adopter of utility clubs, putting a 24* Hogan in his bag last year. After finishing the tournament season, he began to wonder if his irons could be improved. His Callaway irons had been thoroughly analyzed, tested and even Moment of Inertia Matched earlier in the year.

In testing with the Shaft Max, we focused on shaft length and flex. As we knew, the Judge has a short, rather violent swing with a quick tempo. It was surprising during testing on the Shaft Max to discover the Judge’s flex rating was 8.0. We decided to try a shorter stiffer shaft. The Judge demoed a set of MacGregor irons with stiff Rifle shafts. After that test came out positively, we build a single test club with an Aerotech 95 gram graphite shaft, a little shorter in length. We tested the shorter length on the launch monitor and found a small increase in swing speed, another counter-intuitive result.

On-course testing bore out indoor speculation. The ball seemed to “jump” off of the clubhead at a higher speed and distances were definitely a little longer. Time will tell on the consistency and distance control. Overall, this is very promising technology that will be the subject of much future analysis.

On the Radar Screen

I got wrapped up in working on the “Brief History of Shaft Fitting” this month but I don’t want you to think that I missed out on testing new equipment. There are some products coming down the line that have a chance to be “breakthroughs” in their own right. We received a couple of sets of the new E 21 Scandium shafts for testing. Scandium is a material touted as being both stronger and lighter than titanium. One thing for sure, they’re going to have to be a lot better if they plan to earn their $69 retail price per shaft. Both Bob and I built out our sets but then the rainy weather set in so a full evaluation will have to wait until next month. In one “Morning at the Muni” I was getting unusual distances for this time of year. We hear a lot of claims, most don’t bear out but we’re going to be paying a lot of attention to Scandium over the next few weeks.

A few months ago, I predicted the “Death of the $500 Driver.” Now, I’m not so sure. Premium driver shafts are showing up at a rapid rate. The new Matrix Composite Corporation (formerly Apache) OZIK has been getting Tour play. Bob installed one and raves about it. I’ve got one waiting for the right head. The OZIK Silver is $400 - the Gold a whopping $1000. Stulz Golf Technologies is introducing a new premium shaft with a triangular shaft section aimed at stabilizing the shaft for large heads. They’ve sold out their first three small production runs with good results. We’ll have a “first look” next month.

And the big guys are thumping on the jungle drums, trying to build up enthusiasm for 2006. It will be interesting to see how they plan to convince all of us to buy a couple of new sets next year. With the 2006 PGA show looming, it’s an exciting time of year if you’re a golf equipment psycho.

Leith Anderson is a partner in the Golf Lab in Palo Alto. He will answer all questions related to clubmaking and clubfitting personally. Contact Leith Anderson by email: Leith@calgolftech.com. Cell phone 650-743-2816.