Project X Iron Shaft Review

Rifle Project X Iron Shaft Review

By Russ Ryden, Fit2Score, A Dallas Fort Worth Club Fitter & Club Maker
The Golf Center at the Highlands, Carrollton Texas


The Precision Rifle Project X has been with us for a very long time. It somehow got missed when I was in the early days of measuring the vast number of shafts in the market. I noticed its absence when I measured the Project X LZ model. It was originally made by Royal Precision Shaft Company in Connecticut. They were acquired by TrueTemper and the production was moved to Tennessee.  You will see many of the best players in the world playing this shaft. Compared to a Dynamic Gold X100, it is slightly softer in the butt and stiffer in the Mid. Unlike the TrueTemper Dynamic Gold, the  Project X profile is the same for all weight/stiffness variations. The heavier the shaft the stiffer it gets. The profile remains the same for all flex designations.

Lets look at the profile:

The measurements are available only to registered readers

My friend and mentor, Dave Tutelman posted this comment in another discussion of the shaft stiffness range metric. I cannot express my thoughts about this new metric any better than he did. “A big advantage of “measuring” shaft stiffness by plotting the EI curve is that you can do mathematical operations like this. You chose a simple one, with simple arithmetic. But it isn’t that hard to use a butt-biased weighting function that will predict frequency, or a tip-biased weighting function to predict trajectory height. The combination of a known EI profile and spreadsheet capabilities means it’s just arithmetic. As we understand shafts better, EI will not become obsolete; just the way we use and display it will.”


Dynamic Gold AMT – Tour Issue – Golf Shaft Review

Dynamic Gold AMT Iron Shafts

By Russ Ryden and Mark Maness

By Russ Ryden, Fit2Score, A Dallas Fort Worth Club Fitter & Club Maker
The Golf Center at the Highlands, Carrollton Texas


AMT stands for Ascending Mass Technology. It is not a new concept. Ping has had ascending weight shafts for many years. Nippon 999’s were ascending. Aerotech Players Spec were ascending. If you are not a club maker you probably have not been exposed to the concept. Briefly, there are primarily two kinds of shafts; constant weight tapers and parallel’s. Constant weight tapers are made to length in the factory and the shafts in the set are all the same weight even though they are different lengths. Parallels are made to one length in the factory. The club maker cuts them to the length needed for the club he is building. As they are cut shorter they weigh less. The shafts in a set are lighter in the short irons than in the long irons.  I wrote an article about this some years ago in the technical stuff section of this site; Constant Weight vs Parallel Iron Shafts.

Iron heads get heavier as the the numbers get higher. The 4 iron head is heavier than the 3 iron, the 5 iron is heavier than the 4 iron and so on down to the gap wedge. In sets made of parallel shafts, the shafts get lighter while the head gets heavier. In sets made from constant weight shafts, the shafts are the same weight while the heads get heavier. In ASCENDING WEIGHT sets, the shafts get heavier as the heads get heavier. This has always been an attraction the club builders that create MOI, Moment of Inertia, matched sets.

The technical discussion, measurements and testing results are available only to registered readers

This is a great step forward in iron shaft technology. Keep it coming, True Temper, the club building community has waited a long time for a set of iron shafts like this!

EI Measurement Refined

Adjusting 3 Point Bend Measurements for Tube Deformation

By Russ Ryden, Fit2Score, A Dallas Fort Worth Club Fitter & Club Maker
The Golf Center at the Highlands, Carrollton Texas

EI profiling is one of several methods used by shaft designers and club fitters to understand a golf shaft. In several research papers on golf shafts, 3 point EI bend testing is faulted for failing to account for tube deformation under load. With the assistance and coaching from Dave Tutelman I began a study of shaft deformation in a 3 point bending test. That study, which lasted over a year, is now complete. I have developed a simple measuring process to compensate for tube deformation in 3 point EI measurements.

These illustrations show a cross section of the shaft measuring process and graphically illustrates the deformation issue.

Understand EI Deformation 1Figure 1:  The typical 3 point measuring system uses a gauge positioned at the top of the shaft. A preload is applied to the shaft, and the measuring gauge is set to zero.

This set of drawings is vastly exaggerated to illustrate the point. In fact the deformation of the shaft is a very small percentage of the bending of the shaft.


Understand_EI_Deformation 2Figure 2:
 When load is applied to the shaft, It bends. Golf shafts are hollow tubes, not only do they bend, they also deform, becoming oval. Deformation is a function of the hoop strength of the shaft. In linear bend testing, the oval deformation is a source of error. We want to measure the bending of the centerline of the shaft shown here as 10 units. We actually measure both ovaling and bending.



Understand_EI_Deformation 3Figure 3:  Remember, In these drawings, the ovalization of the shaft is vastly exaggerated. The top to bottom dimension of the loaded shaft changes by 40 units. Part of that dimension, 30 units is the deformation of the shaft. Not the bending of the shaft.


Understand_EI_Deformation 4Figure 4:  The correction; measure both the top wall and the bottom wall of the shaft to calculate how much the shaft deformed. Subtract half of that difference from the top wall measurement. In this exaggerated illustration, the actual centerline deflection is 10 units. That is determined by subtracting half the difference between the top and bottom wall deflection from the top wall deflection.

This deformation occurs in three places, the left support, the center press and the right support. To accurately determine the centerline EI, all three deformations must me measured and accounted for in the calculation of EI.Understand EI Deformation 5

Figure 5:  This is an EI instrument built for researching and understanding tube deformation during 3 point loading. A gauge under the shaft measures deformation at the bottom wall. The difference between the top and bottom gauge is ovalization of the shaft. A third gauge measures deformation at the beam support. After studying many shafts, we can now forecast deformation from hoop stiffness alone. 

ActualDeformationAdjustmentThe ovalizing of the shaft shown above is exaggerated for the purpose of the illustration. In fact it is typically less that 2% near the tip and as much as 20% near the butt. The correction does not change the shape of the EI graphics. It does modify the slope. The butt section of shafts is revealed as stiffer than uncorrected top wall deformation data. As you can see here, the subtle stiffness changes shown in inch by inch 3 point profiling are apparent in both the uncorrected and adjusted graphics. Those stiffness bumps that are the essence of feel and performance are apparent in both graphics. The adjusted graphics make butt stiffness more accurate going forward.

The three gauge instrument shown above is time consuming to use. It is now available for purchase. We knew at the onset of this research project that deformation was going to correlate to the hoop strength measurements we are already taking with a single gauge instrument.

HoopDeformationAdjustmentApplying a multiplier to the hoop deformation we have been measuring, we correct the EI data. In this illustration you can barely see a difference between the 4 point measured deformation and the 1 point + hoop adjusted deformation. The measured deformation is done at both the tip and butt supports and the press. The hoop deformation is done under the press, applying the load to the shaft while it is firmly supported on a block of metal.

A great number of shafts with different materials have been run through the 4 point measurement process. A universal correction factor has been shown to apply universally to all shafts we have tested. Hoop deformation against a solid block is a method that accurately corrects top wall measurement to center line bending. This should forever end the critique of the accuracy of 3 point measurement of golf shafts. I am indebted to my friend Dave Tutelman for his guidance and assistance as we worked on this project for over a year.


Golf Shaft Review KBS Tour 105 TaylorMade Stock

KBS Tour 105 TaylorMade Stock Iron Shaft

By Russ Ryden, A Golf Digest America’s 100 Best Clubfitter
Fit2Score, Dallas Fort Worth, Texas

Many of you have probably seen a KBS Tour 105 shaft in stock TaylorMade RSi 1 and RSi2 irons. As of the date this review was published this shaft is not available in the USA after market, the review samples were shipped from the KBS factory in Taiwan.

ParallelvsTaperTipIllustrationThe KBS Tour 105 used in the TaylorMade RSi’s are parallel shafts. A taper version will soon be available to club makers in the USA. For those that are not club makers and are not familiar with the terms parallel and taper let me explain. This illustrations shows the bore in the hosel of a club head. Some heads, like the RSi1 and RSi2 have parallel bores. The hole in which the shaft is inserted has parallel sides. They are typically 0.370″ diameter. They are designed for parallel tip shafts. Heads designed for constant weight taper tip shafts have a tapered bore. The bottom of the hole is 0.355″ diameter and slowly increases in diameter.

Taper tip shafts are sold in sets. Each shaft in the set is specifically designed for a particular iron, 3i, 4i, 5i, etc. The shaft lengths in the set are in 1/2″ increments and typically weigh the same despite being different lengths. The stiffness of the shafts is set by the designer. The shafts are butt trimmed by the club maker to get to the lengths needed for you set. Parallel shafts are sold individually, one length for the entire set. They are tip trimmed by the club maker to create stiffness for the different irons then butt trimmed to create the lengths needed for the set. Because they are trimmed from both ends, the shaft weight gets lighter as it gets shorter.

The balance of sets made with constant weight tapers and parallels is different. You should not attach a value judgement to that fact. But you should realize that if you are accustomed to the balance of one design, changing designs will affect your game despite the fact that the swing weights will be the same. If you want to learn more about this it is explained in greater depth in the technical article, Parallel and Constant Weight Iron Shafts.

Now that you have a basic understanding of Parallel shafts, lets take a look at the KBS Tour 105 parallels.

The technical discussion, measurements and testing results are available only to registered readers

The after market addition to the KBS Tour line of shafts, the 105 constant weight tapers is coming soon. Stay tuned, 105 grams is a great weight and will be a great compliment to the CTaper light in a fitting system matrix of shafts.

Nippon N.S.Pro Super Peening

Nippon N.S.Pro Super Peening

By Russ Ryden, A Golf Digest America’s 100 Best Clubfitter
Fit2Score, Dallas Fort Worth, Texas


I am in the process of rebuilding the Fit2Score shaft knowledge base with 3 iron and wedge profiles. Nippon sent a box full of review samples including the N.S.Pro Super Peening Orange and Blue. I had briefly looked at the Super Peening Blue wedge shafts in the past. They had been suggested as a wedge addition to my fitting system. Readers have asked several times about these shaft so I was interested in getting a full set of measurements of these samples.

The N.S.Pro Super Peening shafts are no longer shown the the Nippon brochures. I had to find a 2008 catalog to see how Nippon presented the shafts. The descriptions there were brief, and the terms used to describe the shafts Orange = Mid Kick Point and Blue = Butt Kick Point brought me back to a time when I was taught to think about shafts with those terms. We were taught back then that the higher the kick point the lower the shaft would launch. My exploration of EI profiles vastly expanded my understanding of a golf shaft beyond things like kick point and frequency matching. As I looked at the measurement of these two shafts I realized they are good examples to discuss the nature of 3 point EI profiles.

The technical discussion, measurements and testing results are available only to registered readers