The following is a brief summary of how keen observation, the laws of science, and personal innovation all combined in the creation of what has been called “The Best Golf Shaft ever made” – the Nunchuk®.
Gerry Hogan
Early Analysis - Gerry Hogan’s interest in shaft function was triggered some forty odd years ago when he first noticed that multiple steel shafts were bent at the point where the shaft tip exited the hosel. Importantly, he observed that virtually all the shafts were bent forward, seldom, if ever, were they bent backwards.
Had the bending been a result of impacting the earth or the ball then the bending would have been backwards, not forwards. Had the bending occurred as a result of impacting a solid mass, such as a tree branch, the bending would have been located at the site of the contact between shaft and branch and it would be rare that this occurred at the junction of hosel and shaft.
The point that struck Mr. Hogan most forcefully at the time was: if so many shafts were permanently bending in such a manner as to be so obvious, then all shafts must actually be flexing/ bending forward, to some degree in this area. This bending/flexing was occurring in the downswing while the shaft was attempting to recover structurally to a straight line. Perhaps no one else had ever given the matter thought and he decided to examine it!
Take a driver with a manufactured genuine loft of (say) 10 degrees, in the real world of shaft tip forward flexing what was it’s effective loft at and through impact after all of this bending had occurred prior to impact? As time passed, Mr. Hogan continued to experiment to determine the various influences on the clubhead/shaft relationship of the traditional shafts being offered in the marketplace.
Mr. Hogan took the approach that science is a wonderful tool, but every law and every rule from every possible aspect of science involved in the specific entity in question must be identified, understood, applied and satisfied before perfection can possibly be considered.
Bending - Mr.
Hogan determined that shaft bending was caused by
the momentum of the clubhead mass, under quite
dramatic acceleration on the extremity of the shaft,
accelerating past the end of the shaft.
The weakest point will invariably give first, and the weakest
and most vulnerable point in the golf club is that portion of
the shaft immediately above the hosel.
Droop – Droop
is another factor in the golf shaft that supported Mr. Hogan’s
conclusion that things were happening in the golf shaft in
the downswing that were beyond the ability of the naked eye
to detect; the photography in use at the time was not up to
the task either.
The head of the club is located tangential to the shaft axis
and the centrifugal pull from the mass of the clubhead away
from the golfer caused the clubhead to attempt to create a
straight line association with the shaft. The hosel would not
give, so all the bending occurred in the shaft, which was the
only part of the club that could bend.
Twist -
Lastly, Mr Hogan investigated the effects of twist
on the golf shaft caused by the length of the clubhead, heel
to toe, acting as a radial accelerator. The shaft as a
mass/ weight value has a capacity to act as drag
when the clubhead reaches a certain point/level of
acceleration that commences to overtake the relative
acceleration rate of any arc of motion of the shaft, i.e.,
the toe of the club moving at a faster speed than the hosel
causes a twisting of the shaft.
Mr. Hogan determined that three identifiable forces were
working on the same stress point of the shaft.
Developing a Better Shaft – Mr. Hogan turned his attention to designing a shaft that would support the lower end of the shaft to such a degree that it could easily overcome/ resist all of these forces and redistribute them higher and more evenly throughout the shaft.
Mr. Hogan described his intent as follows:
“I had a specific objective in mind.
I intended that the head and the lower segment of shaft for a (specified) distance must function as a single entity offering zero degrees of bending.”
"I also intended that this head/ lower segment of shaft acting as one entity would act in the same way relative to the lag that I wanted."
"If the head could not pass the lower shaft then it would be forced to carry the lower shaft with it, as a single unit of mass. This would ensure the lag effect I sought as a primary fundamental of controlled function."
"My invention required that all possible bending must be eliminated from the shaft sections above and below that centrally located section. This was the only possible way to gain complete control over the clubhead and the clubface via the shaft."
"My intention was to control droop via the rigid upper and lower sections and only a very short central section over which bending/ bowing is designed to occur. Importantly, controlling droop has a direct influence on where the center of the clubface is, at any given time."
"I intended to control the location and recovery rate of shaft twisting by designing the central section of the shaft to be highly resistant to twisting in all directions. Twisting does occur in the lower shaft section on a very limited basis with an exceptional high recovery rate."
The Nunchuk® precision shaft is the realization of these intentions, a shaft design that minimizes the variables of bending, twisting and droop of the golf shaft through the impact zone with the golf ball. Golfers should expect to impact the "sweet spot" of the clubface more often, with the clubface looking at the intended line of flight. Thus, producing better club head to ball speed efficiency and better accuracy.
Less loss of clubhead momentum through impact - The distance that the ball travels is not determined by the speed of travel of the clubhead entering into impact, but by the speed of the clubhead at the point of separation between ball and face. The average deceleration of the clubhead with a conventional shaft throughout impact is approximately 20%, to as much as 24%.
Since the lower arm of the Nunchuk® shaft is designed not to flex, the clubhead is much better supported throughout impact and beyond. As far as testing has been able to determine, the losses of clubhead speed with the Nunchuk® shaft are below 10%, meaning that the ball should travel faster at the point of separation than with a conventional shaft.
The lower arm
of The NUNCHUK® is
designed NOT to flex,
so there is LESS loss of momentum!
CLICK IMAGE TO PLAY BRIEF VIDEO
The ordinary golfer (high and low handicap) – Today’s golfer is faced with an infinite amount of shaft choices. Unfortunately, the shafts offered in the marketplace have not resolved issues identified by Mr. Hogan many years ago.
The more flex a golf shaft has, the greater the margin of error in returning the clubface back to square at impact.
The more twisting a golf shaft experiences, the more difficult it becomes to return the clubhead/ clubface correctly to impact.
The more droop in the shaft, the more difficult it becomes to return the clubhead to the ball.
The longer the shaft in any given golf club,
the more the shaft fitted to it will be subject
to all three of the above.
The heavier the clubhead is, the more the shaft will flex and droop.
The larger the clubhead is and the longer it is from heel to toe, the greater the potential from all three issues above.
Who are the twistiest, most flexible and most droop-prone golf clubs with the largest, heaviest clubheads and longest, lightest shafts designed for, manufactured for and sold to? Unfortunately, the answer is, ''average golfers'' - male and female, young and old - especially those who have the least ability to use them and the least opportunity to learn how to use them.
Enter the Nunchuk® – nVentix Golf, in consultation with Mr. Hogan, has now released the Nunchuk® precision shaft, which is designed to overcome ALL the issues identified above. The name “Nunchuk” was chosen because of the influence and principles on the shaft design of the ancient two-lever flail frequently associated with East Asian martial arts. nVentix Golf plans to continue working with Mr. Hogan to develop additional wood shafts and iron shafts to bring this great technology advancement to an entire set of golf clubs.
Download PDF of "The Science Behind the NUNCHUK®"
