I spend more time practicing putting (on the carpet in my office, which stimps at about 13, I figure) than any other part of my game, and I read with interest all the articles about putter design and the putting stroke that I come across. I also follow new developments in putter design, many of which turn out to be pointless, ridiculous, overhyped, or just plain wrong (see my review of the Stability Shaft by Breakthrough Golf Technology, on which more later in this column.)
In pursuit of better putting I have experimented with counterweighting by adding grip weights to my putters, for which there is a factual physical basis, unlike many of the spurious putting “innovations” which are touted in Golf Channel infomercials and even by big-name manufacturers. Extrapolating the concept of increasing stability by redistributing mass from the shaft to the ends of the club, the next thing that I wanted to do was to replace the steel shaft in my putter with a graphite shaft.
Changing from a steel putter shaft to a graphite shaft can save as much as 100 grams, freeing up that mass to be moved to the head and the grip end of the club while keeping the same total weight; a change which, as I explain in the counter-weighting article, increases the club’s stability in the long axis, which benefits speed control.
But before I talk about my putter-shaft experiment, let’s look at the current state of the art in graphite composite and multi-material putter shafts.
Who is making graphite putter shafts, and why?
There are three manufacturers that I know of that are currently marketing graphite-composite shafts, or shafts incorporating graphite-composite, for putters: Odyssey, with their Stroke Lab shafts (though not available as a retrofit item); Breakthrough Golf Technology (BGT) with their so-called Stability Shaft (retail cost $129.99 to $299.99); and LA Golf, which markets a line of graphite shafts up and down the bag, including three for putters (retail cost $419.00).
Of those three companies only Odyssey specifically cites the redistribution of mass as a benefit of the use of their graphite-composite shaft, and their Stroke Lab line of putters include the use of additional weights in the head and the grip of the club to redistribute the mass saved in the shaft. Both Breakthrough Golf Technology and LA Golf, however, cite the so-called “low-torque” characteristics of their shafts in preventing “head wobble” as the prime benefit.
These three manufacturers differ not only in the claims they make for the benefits of their composite shafts, but in the details of their construction. The Odyssey Stroke Lab shaft and the BGT Stability Shaft are multi-material units which combine a graphite-composite tube for the upper portion of the shaft with a length of conventional steel shafting for the lower portion which mates with the putter head. The Stroke Lab shaft uses unspecified means to bond the steel and graphite sections of their shaft together; the BGT design uses both an aluminum stiffener and a separate aluminum connector between the two sections.
The LA Golf putter shafts, on the other hand, are 100% graphite composite material, but like BGT, their advertising cites the “stiff, low torque” characteristics of their shafts in preventing head wobble or deflection that is “caused by traditional shafts” as the advantage of their product.
So let’s break it down:
Both BGT and LA Golf claim that conventional steel putter shafts are weak—weak enough to twist in response to the forces exerted on them by the inertial forces resulting from the movement of the club acting on the mass of the club head.
The following quote is from the LA Golf website:
“Recent data shows that outside 12 feet, when a player begins forward motion the head wiggles slightly and that instability can change your putt line even if you read the line correctly and put the perfect stroke on it.The head also wiggles when you strike the putt even fractionally off center (which everyone does) causing you to lose distance on the roll.”
It is, of course, utter nonsense to attribute the motions described in that quote to flex in the shaft; to do so is to reveal a complete lack of understanding of the magnitudes of the forces involved, and the ability of the structures being discussed to handle the forces to which they are subjected.
Of course, the people who want you to shell out anywhere from $130 to over $400 for a new putter shaft are counting on the average golfer taking their quasi-scientific marketing jargon at face value—but if you keep reading you will learn how they are leading you astray.
What do they mean when they say “torque”?
What the ad copy for golf club shafts refers to, incorrectly, as “torque”, is the torsional stiffness of the golf shaft. It’s measured by clamping the butt end end of the shaft in a fixed position and applying one foot-pound of torque—that is, a force of one pound acting at a distance of one foot from the center of the shaft—at a point further down the shaft and measuring how much the shaft twists. (The results obtained from this test can be greatly affected by the testing method—especially by the length of shaft between the clamping point and the point at which the force is applied—so comparisons between the data given by different manufacturers are not necessarily valid.)
This “torque” number can range from three or four degrees for a steel shaft to upwards of eight degrees for the more flexible graphite shafts—but these numbers are only really relevant for full-swing clubs: wedges, irons, hybrids, and woods; clubs in which the club face contacts the ball at speeds of up to 125 miles per hour (Note: PGA Tour pros average about 110 mph of club head speed with driver, and some go much higher.) Those high club head speeds produce very high resultant forces on the club head, and therefore, significant torsional forces in the club shaft.
For putters the force acting on the shaft, even as a result of impact with the ball, is orders of magnitude lower than for full-swing clubs, and the torque input to the shaft resulting from inertial forces acting on the club head before contact with the ball are so far below the threshold which would result in deformation of the shaft that they can be ignored.
The bottom line…
The claims that are being made by Breakthrough Golf Technology and LA Golf—that larger, heavier modern putter heads “overpower” a conventional steel shaft, and thus require their expensive, over-engineered offerings, which are actually no stiffer in torsion than a $9 generic steel putter shaft—are complete nonsense.
The all-graphite composite shafts from LA Golf are the right idea, but they appear to be doing the right thing for the wrong reason—and they cost waaay too much.
The sophisticated multi-component shafts such as the BGT unit and the Odyssey Stroke lab shaft introduce complexity where simplicity will do; the complexity adds no value, and actually compromises the potential effectiveness of lighter-weight graphite composite construction by the use of a steel lower shaft. The BGT Stability Shaft is the most egregious offender of the two, due to their use of two aluminum components mid-shaft, at the junction of the graphite and steel portions, which returns mass to the middle of the club.
In Part II of my look at graphite-composite putter shafts I will walk you through my home-workshop experiments, in which I modified my bargain-bin Tight Lies Anser-style putter as an experimental test bed.
Stay tuned.
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