Revolutionizing the Game
Golf Equipment
Golf is one of the most technologically-advanced sports, with legions of engineers shaving microns off club faces, designing shoes with AI, and formulating new tee materials to give players just a little more of an edge.
With the US Open in our backyard, we turned our X-rays toward top-shelf golf equipment, including a golf club that took 20 years to design. We were surprised to see how sophisticated this equipment has become–and found a few places where imperfections still made it through. Let’s explore.
Nike Air Zoom Infinity Tour
Conventional golf shoes are uncomfortable, with stiff soles and lots of spikes. Not these: Nike designed a running shoe for the golf course and optimized it to transfer swing energy from the ground, through the shoe, and eventually into the club head.
Shoe teardowns usually involve a saw and some destructive hacking, but with X-ray CT we’re able to see this shoe’s outer and inner details without destroying it.
Nike uses a special breathable waterproof fabric that’s digitally woven as a single upper. This means fewer stitching operations, precision control over fit, and, Nike claims, 3.5 million pounds of waste saved from landfills.
You’re literally walking on air in these shoes. Hexagonal, dot-welded airbags sit between the insole and midsole. They provide cushioning in key zones of the shoe, right above the futuristic spikes at the heel and the metatarsals.
Titleist TSi3
Titleist’s driver lineup is entirely titanium; the material is strong enough that Titleist’s driver heads can be completely hollow. That makes a difference when it comes to one of a golf club’s most essential features: sounding a perfect sweet-spot ping. Let’s look at the TSi3, a $549 flagship product.
The screw that attaches the driver’s head to its shaft is captive—a nice touch that means you won’t spend time on your knees in wet grass trying to find a dropped screw. More interesting, however, is the opening from the shaft socket to the inside of the club. Designers, hunting for ways to optimize weight distribution within the club, removed a few precious grams from this location. The opening may also help deliver a better strike sound.
This little mechanism—a steel weight on a track, sandwiched between the club and a notched plastic component—has a big impact on the club head’s center of gravity. Adjustable via a screw, it gives the golfer five presets to choose from, each of which subtly modifies your swing.
ATI 425 aerospace titanium—a special alloy only made in a single foundry in Pittsburgh—has a diverse application list: rotor-aircraft, naval systems, the Phoenix Mars lander, and this golf club. The face has a subtle curve to optimize sound and strength, and is welded onto the body.
TaylorMade Carbonwood Stealth Plus Driver
All-titanium drivers have dominated the market since the late 1990s, but TaylorMade decided to take a different approach. Years of studies showed TaylorMade that a carbon fiber club face is 44% lighter than a traditional titanium face and can generate more ball speed off the club. However, durability and acoustics weren’t ideal.
TaylorMade overcame those drawbacks in the Stealth Plus, a $599 driver that combines titanium and carbon fiber—two materials that are difficult to work with in isolation, and even more difficult to join together.
Inside the club head, we see stiffening ribs that improve its acoustics—a feature that TaylorMade patented in 1997.
Compared to the previous club, adjustability here is limited. A weight moves the center of gravity to the back of the club, making it more forgiving. A screw allows this weight to be adjusted, but only front-to-back; lateral adjustment is a $50 upgrade.
The club face is made with carbon fiber and polyurethane. In an industrial CT scan reconstruction, we use color to represent material density; this club’s face is much less dense than its titanium body. The face is notably larger than the other driver’s, and is epoxied rather than welded into place.
We see that same opening between the shaft socket and the inside of the club head that we saw on the Titleist driver, and a different approach to the captive screw. We also see some porosity in the metal—a defect that’s common in metal castings and that’s immediately visible in industrial CT scans.
