Normally when you try to achieve a specific grip size, you look at the core size of the grip and the dimension of the butt end of the shaft listed in the catalog or on the website. Then you refer to a clubmaking book (or the new Hireko Grip Module) to see what the final size will be. In many cases you will be perfectly fine, but in a few cases the measurements could be quite off. This is why it is important for the clubmaker or individual re-gripping their clubs to measure the butt end of the shaft with a pair of calipers or micrometers to be absolutely sure.

The majority of cases where the grip sizing will be inaccurate by using the information in the catalog and in a clubmaking book will be when the shaft has a constant taper at the butt end. One popular line of grip is a good example of these. The Aldila NV, NVS and VS Proto shafts all have this constant taper as part of their design. Glancing at our catalog or website, you will see that the butt ends on these particular shafts are between 0.620” - 0.630”, which is much larger than the majority of the shafts on the market. However, this measurement only applies the very butt end of the shaft.

Since we rarely play with the full length of a shaft, some material is removed from the butt end. For example, those select Aldila wood shafts are all 46” in length. Installed into a standard titanium driver at 45”, approximately 2.5” will be removed from the butt end (taking in account the bottom of bore to ground line measurement of the head and the grip cap). At this point, the diameter is now 0.015” smaller. By the time the grip ends, the shaft underneath the mouth of the grip is 0.540” creating a smaller dimension underneath the lower hand. Measuring 2” down from the butt end of the completed club (a common point of reference for grip sizing) these shafts will actually measure Men’s Standard size.

Not to confuse matters worse, but to explain how the rate of taper affects grip sizing, let’s look at the opposite scenario. This occurs when the shaft has a long parallel butt section longer than the length of the grip, or simply stated that the grip remains the dimension of the very butt end of the shaft for an extended length. One example of this is the True Temper Dynamic Gold SL iron shaft. The S300 iron shaft is .610” at the butt end and remains that size for 18 inches. Even though the Aldila NV may appear at the tip of the ice berg to suggest a larger grip size will occur with the same grip installed as compared to the Dynamic Gold SL, it is the rate of taper of the butt end that influences the final grip size along the entire length of the shaft.

Hopefully you gain a little bit more knowledge about re-gripping that you may not have thought of and to understand that grip sizing is not all cut and dry as it appears.

by Jeff Summitt
Hireko Technical Director
jsummitt@hirekogolf.com