In 1996, a larger butt shaft diameter emerged as the newest high-tech development in the ever-evolving world of golf equipment. We saw shaft with bulges. Now big butts and big TIP. All topped with big head? If nothing else, if appears obvious by now - for shafts, BIG is definitely IN.

Many golf club manufacturers have introduced, or are developing shafts for with tip diameter greater than the traditional parallel tip diameters of 0.335 inch for woods and 0.370 inch for irons. Is the move to larger butts and now bigger tip shaft diameters merely a marketing move, designed to lure golfer into fanning the scorching flames of equipment commerce even hotter? Or is there a real technological, performance-related reason for increasing the shaft tip size?

By now, golfers are aware of the ongoing developments of the big butt diameter shafts. By increasing the diameter of the shaft's butt end, golf club designers pushed the envelope of total weight decrease and clubhead feel increase. Increasing the butt diameter makes it possible to drop the weight of the grip by as much as 40 grams.

So, now why the increase in tip diameters? Shaft tip diameters, have remained virtually constant for decades. While some companies still use .335 inch taper tip diameter shafts for their irons, most adhere to the common 0.370-inch parallel tip. For their woods, most manufacturers prefer a traditional 0.335-inch parallel tip.

The primary reason manufacturers and their OEM-finished club customers develop shafts with larger tip diameters is to create shafts with greater control, accuracy and durability. It is the designers' belief the decrease in torque and reduction in tip flexing of the shaft automatically results from increasing the shaft tip diameter, and, thus, brings about the desired outcome of accuracy plus control. But, in the often complicated world of shaft design, there are two common sense principles which developments - the larger the diameter and the thicker the walls of the shaft, the greater the stiffness and lower the toque (greater resistance to shaft twisting).

Tip durability in graphite shafts is a design factor which manufacturers constantly keep under vigilance. Currently, shaft companies spend a lot of time and expense preventing shaft tip breakage. By increasing the diameter, the shaft tip becomes stronger, more resistant to wear and tear and costs less to manufacture. Lower torque and greater durability achieved for a lower cost - so far, big tips look like an economic advantage.

PLAYABILITY
In addition to torque reduction, increasing tip diameter generates an increase in stiffness. What about shaft flexibility with an increased tip size? And does decreased torque really bring about improved accuracy? The answer to these questions cannot be applied across the board. Unlike the big butt phenomenon, in which shaft manufacturers predominantly chose the 0.865-inch butt diameter, the big tip shaft has no 'standard' dimensions.

Currently, the big tip shafts in golf clubs range from 0.350-inch to 0.410-inch diameter in the wood shafts and 0.400-inch to 0.500-inch diameter among the iron shafts. Because the diameter is such an important part of a shaft's stiffness and torque, golf club and shaft companies must be careful when determining the amount to the tip size increase. Too larger an increase and the feel of the shaft becomes too stiff, completely offsetting the expected accuracy improvement from torque reduction.

PERFORMANCE
The hope of improving accuracy and control by lowering the torque is not new. Experienced clubmakers will remember the competition between composite shaft makers in the mid- to late- 1980s to create shafts with lower and lower torque measurements. The wood shaft's torque was driven below two degrees - given the levels of shaft stiffness at the time - however, almost all of the two-degree torque shafts simply were too stiff for all but a very few superstrong-swinging players.

Learning from experience, the last decade witnessed a total reversal in shaft development. Years of testing with two-degree torque shafts revealed that while machine testing could perceive a slight accuracy advantage to the lower torque levels, real players testing did not disclose what could honestly be perceived as visible improvement.

The most widely used shafts in the game today possess torque ratings higher than four degrees, with shaft like the Callaway RCH-90 and 96 revealing static torque measurements approaching six degrees.

Another point which seems to verify that torque is not much of a component in accuracy is the fact there are currently far more players on the PGA Tour using graphite shafts with torque above 3.5 degrees than below.

FEEL
What about the feel of a shaft crafted with the larger tip diameter? The golf industry's initial experience with lowering torque also taught us torsional stiffness and flex interact to ordain the overall stiffness feel of the shaft. For any level of stiffness, the lower the torque the, the stiffer the shaft feels to the golfer.

The big tip shaft design appears to be faced with a challenge. If the tip diameter is increased enough to generate a more noticeable change in accuracy than seen in the past, the stiffness may become too great. On the other hand, if the diameter increase is made to be very slight to retain proper stiffness levels, any improvement in control may be insignificant.

Therefore, any increase in tip diameter must include additional design elements t keep the stiffness within acceptable levels as well as to prevent the actual torque from dropping too low. Big tip or not , if the torque drops to the two degree level and the tip diameter is significantly larger, the shaft will be hard pressed to retain a crisp, solid feel at impact.

TESTING
From actual testing of a number of the industry's current big tip shafts, the frequency and torque are not at all unlike the specifications for frequency and torque of conventional tip shafts.

Only in the case of the Wilson Fat shaft - with its huge 0.500-inch, over-hosel tip shaft - was the torque engineered to be much lower than the company,s average torque for conventional tip R and S flex graphite designs.

Shaft companies told The Clubmaker that utilizing the large tip feature to obtain more control and accuracy by lowering torque is not the direction the majority of the club companies wish to pursue. Whether lower torque/higher stiffness still ultimately be the direction the industry chooses, however, remain to be seem.

Obviously, the big tip shaft design is still in its developmental stages, and requires further testing. And in The Clubmaker's anaylsis, considerable work is still necessary before a big tip increase can deliver the performance desired by its developers.

The golf equipment industry clearly proved that improvements in accuracy and control cannot be made at the expense of proper feel for stiffness and overall crispness. Designers are finding the rate of taper is a significant contributor to a shaft's overall solid feel and performance. For example, among the big tip shafts tested, shafts of the same larger tip diameter revealed completely different feel and performance results.

It cannot be said simply choosing one specifically larger tip diameter ensures a good performance results. And, it may soon be discovered the real secret to success with the big tip shaft will be in how the shaft tapers in outside and inside diameter before it gets to that larger tip diameter.

Some manufacturers, Golfsmith included, are currently looking at rapid tapering of the butt and/or mid-sections to the larger tip diameter as a way to restore overall flexibility and crispness feel which otherwise could be lost with the increased shaft tip diameter.

But until this happens, it appears the primary reason the finished club manufacturers are pursuing the development of the larger tip diameter shafts lies in the products individuality their different tip diameter gives them in the marketplace.

Whether the big tip shaft is really more of marketing and cost savings move by the finished club companies or really performance enhancement is still up in the air.

However, until a great deal more work is completely on the big tip shaft design, the development of the larger butt diameter shaft appears to have considerably more substance than its little brother, the big tip.

Suffice to say, this is not the final word on this interesting new development in clubmaking, and we'll probably be seeing a lot more of the big tips, before we see less.

Philip Ang, 1999-2000 Winner International Clubmaker of the Year
conferred by Golf Clubmakers Association (GCA) - USA compiles this article from Golfsmith Tech Report.