Evolution of the Club
Over the decades, the sport of golf has seen many technological innovations, most notably in the design and engineering of the golf club. Many of these advances have strived to more efficiently utilize the mass of the club head, something that can help the ball travel faster, farther and with more control. "Science of Golf" is produced in partnership with the United States Golf Association and Chevron.
DAN HICKS reporting: For the 2013 U.S. Open, the best golfers in the world will gather at one of the country's most notable and historic courses: Merion Golf Club in Pennsylvania.
MIKE TROSTEL (Historian, USGA Museum): The 2013 U.S. Open will be the eighteenth USGA championship held at Merion. This will be the fifth U.S. Open held there.
HICKS: Known for its wicker basket flagsticks, Merion is one of the most celebrated golf courses in the country, with its East Course dating back to 1912. Some of golf's greatest players have made history here: Olin Dutra, Dorothy Porter, Ben Hogan, Lee Trevino, among others. Beyond just tradition and history, the 2013 U.S. Open will showcase how the design and engineering of the golf club has evolved over the decades.
TROSTEL: The earliest golf clubs were really handcrafted. They had no standard shape or form. But they were made by individual craftsman over in Scotland.
HICKS: Most golf clubs were originally made from hardwoods, like persimmon, used not only for its durability, but also for its high-density mass.
MATT PRINGLE (Equipment Standards, USGA): Persimmon is hard and it's dense so you can get the club mass where you need to be in a fairly small package, and it's strong.
HICKS: Mass is the measurement of an object's resistance to acceleration. The more mass of an object, the more force is required to accelerate it. Matt Pringle, an engineer at the United States Golf Association Research and Test Center, says the mass of the club head is crucial to increasing the amount of force that's imparted onto the ball, making it travel faster, and farther. The more mass of a club head, the more force it produces.
PRINGLE: From an engineering perspective of creating a club that's large and distributes the weight over a big volume and gives you the flexibility, that's a great choice.
HICKS: Not only is the club's mass important, but how it's distributed in the club head can allow for more control when hitting the ball. This control is due to something in physics called rotational inertia, a scientific principle that says the farther an object's mass is away from the axis of rotation, the harder it is for the object to rotate.
PRINGLE: Back then there was this feeling like, ‘I want to get the mass right behind the ball so I can hit the ball, you know, and give it a good solid hit.’ Now, we know it's better to spread that mass out.
HICKS: At the USGA Research and Test Center, engineers test clubs to ensure that technology isn't more important than skill in golf. In the main test lab, they use a robotic arm to swing clubs at controlled speeds to test their effectiveness. For this demo, Pringle first loads an older wood club.
PRINGLE: We've got an old-fashioned laminated maple wood head because it's wood, it tends to be a lot smaller than drivers of today, so if we hit it off center, it's going to twist a lot more at impact and that means it's going to lose a lot more of ball speed and it's going to start off line more.
HICKS: Because the club head is made of wood, its "spring" quality, or ability to store and release the energy of the ball's impact, is lessened, which reduces the ball's speed. Instead, some energy is lost in the form of sound, and heat.
PRINGLE: During an impact, the ball compresses, takes up all the energy of impact, and releases it, and none of it is stored in the club like it is with a modern driver.
HICKS: Around 1980, metal club heads began to replace wood as the preferred material used in drivers.
PRINGLE: The first materials to be used for woods at that time were stainless steel. The clubs were fairly small. The face materials and shells were quite thick compared to what they are today.
HICKS: Using metal instead of wood, engineers could design hollow club heads, making them larger, but lightweight to make it easy to swing, while still maintaining their durability.
PRINGLE: We're not increasing the mass at all, but increasing the size of the club makes it more forgiving to hit.
HICKS: Today, one of the more common metals used for club heads is titanium, which is more flexible than stainless steel and much lighter, allowing for an even larger club head.
PRINGLE: This is a pure titanium club and it's considerably larger than a wood club. Might even be a little lighter than the wood. But what they've done now is taken that weight, it's hollow, so all the weight is right at the outside, as far away from the center of mass as they can get it, which then makes it on off-center hits twist a lot less than its wooden counterpart.
HICKS: The modern club also increases the spring quality of the club head when it impacts the ball.
PRINGLE: It's got a fair amount of spring to it. So when it hits that ball, at 110, or 120 miles an hour, it compresses a little bit.
HICKS: Upon impact, the titanium club head stores some of the energy, then releases it into the ball, causing the ball to travel faster.
PRINGLE: So the ball speed off of this is going to be considerably higher than a wooden club even at the same swing speed.
HICKS: Today, the evolution of the golf club continues, with engineers using a variety of new materials and designs, to help disperse the mass of the club and deliver the perfect impact to the ball.
PRINGLE: A modern adjustable driver would probably have stainless steel in it, titanium, aluminum and some carbon fiber, all those things. There could be half a dozen materials in a driver today.
HICKS: While club technology has dramatically evolved since the first U.S. Open at Merion, the USGA continues to ensure that skill, not technology, determines the world's best players as they compete for the 2013 U.S. Open title.