Equipment
How the idea of shaft frequency began
Forty years ago, Kim Braly and his father Dr. Braly went down to West Palm Beach to visit Wilson Golf, and that trip forever changed the way the golf industry thinks about the shafts in golf clubs.
“My father and I invented frequency matching,” Kim told me.
“And what’s that?” I asked.
“It’s the process of matching the stiffness of the shafts in your clubs to the heads so you can hit a golf ball rather than snap the shaft or hit the ball all over the place,” Kim said.
OK, that got my attention. So I ask how he stumbled upon the idea.
“My dad was an engineer and got into golf,” Kim said. “Eventually, I got interested in golf as well. In the early 1980s, we went to see the original ‘Iron Byron.’”
A modern-day golf robot at Titleist’s Manchester Lane Test Facility.
Iron Byron was the first club-testing machine, and it was modeled after smooth-swinging legend Byron Nelson. It’s basically an early robot — a motor in a box with an arm — built to use a regular golf club to hit a golf ball.
Kim and Dr. Braly watched the engineer operating Iron Byron put a club into the mechanical arm, place a ball in front of the club face and then press a button to swing the club. The result: perfection. It produced a high, piercing ball flight that was hit on a rope, not far removed from the storied ball flight of Nelson himself. This was followed by another and another. Kim and his father were ecstatic.
With great anticipation, they watched the engineer load the next club. The results were much different. Balls flew all over the place. The dispersion was awful. The Wilson engineer operating Iron Byron slowed down the machine. Balls flew shorter distances, but they landed closer together. The dispersion had been reduced. This was the inception of their game-changing idea; dispersion was a result of certain shaft characteristics matched with a club head and swing speeds. This “AH HA” moment changed how we fit and purchase golf clubs today.
Based on this observation, Kim and Dr. Braly designed a method to measure the performance of a golf shaft. Later, this led to the concept of frequency: very simply, stiffness is not the letter on the shaft, but a measurement based on characteristics like weight of shaft, weight of the head, length of the shaft and several other characteristics. The year was 1977 and they submitted a patent on this idea called “Frequency Matching.”
Armed with the power of measurement, Kim was ready to change golf shafts forever. He and his father started traveling the PGA Tour, and in doing so became the first “PGA Tour Van.” Over the last 40 years, Kim has worked as a researcher and designer, mastering the golf shaft. He’s worked at True Temper, Royal Precision and is currently as the head designer of research and development at KBS Golf Shafts.
Kim working with a player on his golf equipment.
In 2008, Kim launched a shaft company called KBS, which became the fastest growing shaft company in golf. Since that time, the company has gotten some of the best golfers in the world to use its shafts products, including Rickie Fowler, Justin Rose and Phil Mickelson.
The next time you’re struggling with shots that fly sideways, think about Kim and Dr. Braly. You might want to try try being fit for shafts if you haven’t already, because they may just be the most important part of your golf club.
Neal Shipley was the first to admit that he enjoyed his food while in college. But since his days at Ohio State, he’s slimmed down and earned a PGA Tour Card.
That hasn’t stopped him from having fun with his wedge stampings, though it’s led to some misunderstandings.
On the 54 (degree), we have ‘Big Fudge,'” Shipley told GolfWRX. “It was supposed to be ‘Big Fridge,’ so this happened a little while ago. ‘Big Fridge’ was a nickname between my college teammates and I, with ‘fridge’ meaning stomach, a big stomach.
“We told the Ping guys to put … ‘Big Fridge’ on it, and I think maybe some bad cell service or something, and they thought I said ‘fudge,’ so they put fudge on it.”
On Shipley’s 50-degree he also continues the food theme, this time with his go-to order at the “Golden Arches,” and his stamping “DONS 7.”
“The number 7 meal, the two cheeseburger meal, that was my McDonald’s order, back when I would have McDonald’s frequently,” Shipley shared.
At GolfWRX, we are a community of like-minded individuals who all experience and express our enjoyment of the game in many ways.
It’s that sense of community that drives day-to-day interactions in the forums on topics that range from best driver to what marker you use to mark your ball. It even allows us to share another thing we all love – buying and selling equipment.
Currently, in our GolfWRX buy/sell/trade (BST) forum, @raw10628 has a L.A.B. DF3 putter and Masters putter cover up for grabs.
From the listing: “Some great items here today, time to thin out and make room for next set of gear. All prices include shipping.
LAB DF3 Purple 33.5” 68° lie with TPT – $725. LAB Masters release DF3 cover – $150.”
To check out the full listing in our BST forum, head through the link. If you are curious about the rules to participate in the BST Forum, you can learn more here: GolfWRX BST Rules
Driver: Ping G440 LST (9 degrees)
Shaft: Accra TourZ Green 5-M4
3-wood: Ping G440 Max (15 degrees)
Shaft: Accra TourZ Green 6-M4
5-wood: Ping G440 Max (19 degrees @18)
Shaft: Accra TourZ Green 6-M4
Hybrid: Ping G440 (23 degrees)
Shaft: Oban Isawa Red Hybrid Shaft 04 Flex 70 Gms
Irons: Srixon ZXi7 (5-P)
Shafts: Aerotech SteelFiber Private Reserve i80
Wedges: Cleveland RTZ (50-MID, 54-FULL, 58-MID)
Shafts: Aerotech SteelFiber Private Reserve i105
Putter: L.A.B. Golf OZ.1i
Shaft: ACCRA Putter Shaft
Grips: Golf Pride Tour Velvet
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Maria Torres WITB 2026 (June)
Driver: Ping G440 LST (9 degrees) Shaft: Accra TourZ Green 5-M4 3-wood: Ping G440 Max (15 degrees) Shaft: Accra TourZ Green 6-M4 5-wood: Ping G440...
Eric Cole WITB 2026 (June)
Driver: PXG Lightning Tour Max (9 degrees) Shaft: Project X Titan Yellow 70 TX 3-wood: TaylorMade Qi4D (15 degrees) Shaft:...
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Driver: TaylorMade Qi4D (10.5 degrees) Shaft: Project X Titan Yellow 60 TX 3-wood: TaylorMade Qi4D Tour (15 degrees) Shaft: Project...
TeeBone
Jun 7, 2017 at 5:34 pm
Further, frequency matching a set doesn’t mean that the clubs all have the SAME shaft flexibility, only that the DIFFERENCE in flexibility is uniform from club to club. As the clubs get shorter, frequency and stiffness increase. Add to this the fact that as the clubs get shorter and heavier, they are swung at a slower speed. In the end, each shaft in a set flexes more and more overall as the clubs get longer. This silly “dispersion” theory suggests that a shaft must flex a specific amount to behave consistently.
TeeBone
Jun 7, 2017 at 2:39 pm
Tour players, unless they have a specific shaft manufacturer deal, are free to play whatever shaft they want. Their decision to play graphite over steel has to do with performance, not money.
TeeBone
Jun 7, 2017 at 2:27 pm
So Iron Byron, set at any particular swing speed, only reproduces the same ball flight with one specific shaft flex? This “dispersion” theory would mean that the same shaft can behave quite differently, from swing to swing, for an otherwise same swing input. Nonsense. There is no mention of this in any of the best-regarded scientific studies of shaft flexibility. This is a made-up marketing story designed to sell equipment.
Ned
Jun 6, 2017 at 8:06 am
Brunswick Golf developed the Frequency Matching System in 1981!
Rico
Jun 6, 2017 at 4:04 pm
The article states that the Braly’s submitted a patent for “Frequency Matching” in 1977.
J.
Jun 5, 2017 at 7:15 pm
And stiffness of an EI profile may be invisible to CPM matching? Does SST PURE shaft alignment work better?
Skip
Jun 7, 2017 at 1:18 pm
SST pure is pure Kool-Aid. Drink it if you so choose.
tim crider
Jun 5, 2017 at 4:05 pm
There is no doubt that shots can be saved every round by every player with changes from the shaft to the swing weight to the compression of your golf ball,,, hell practicing on the driving range could improve your game. There is a lot to know about this game and if you have the money and the time you may be able to cash in on these findings. Think how much better play got when shafts changed to steel from hickory. A lot to know and even more to learn. How much more can be found and improved, it was a very good article.
Charles Bartholomew
Jun 5, 2017 at 3:38 pm
Interesting article. A little history lesson now and then is a good thing.
cgasucks
Jun 5, 2017 at 8:20 am
If the Iron Byron can make crappy shots with a shaft that isn’t compatible with its swing speed, imagine it with a human being.
talljohn777
Jun 5, 2017 at 12:14 pm
Yes, if you have a club shaft that is too soft you can slow your swing down to allow the clubhead time to catch up and square, but why would you want to do that? The preference would be to hit a club that matches your top swing speed allowing you to get the most out of your swing.
artie j
Jun 5, 2017 at 6:59 am
I didn’t know the backstory. Very cool article Ryan
SH
Jun 4, 2017 at 10:25 am
Yup, awesome