Callaway Research and Development

Callaway Golf Research and Development

Research and Development (R&D) is - and has always been - the heartbeat of Callaway Golf Company. Each year they spend more than $25 million designing, building and testing premium, innovative golf equipment that helps the average golfer find more enjoyment from the game. Every Callaway Golf product begins as an idea, then travels the rigorous road of computer-aided design, advanced computer modeling, durability trials, and finally robot and player testing. Not until each of these processes confirms that the new product is Demonstrably Superior to and Pleasingly Different from every other club, ball or putter on the market - including Callaway's own - does it earn the Callaway Golf name.

The following three articles written by Callaway Golf's Richard C. Helmstetter, Senior Executive Vice President and Chief of New Products, explore the dedicated research work and extensive processes that go into the development of the Demonstrably Superior to and Pleasingly Different products manufactured by Callaway Golf Company.

CTU 30 The Evolution of Rule 35

The new CTU 30 golf ball - with its super-thin cover at 30 thousandths of an inch - is based on the original Rule 35 construction, with improvements and refinements that make it an even better performing, solid core, three-piece golf ball. Let's take a look at some of the ways that our Callaway Golf R&D team evaluated the existing Rule 35 Softfeel and Firmfeel technology and asked: "What can we do to make it even better?"


	Callaway Golf scientists and engineers developed a proprietary cover casting process that gives the CTU 30 its super-thin cover.

The differences between the new CTU 30 Red and Blue versus the Rule 35 Firmfeel (red) and Softfeel (blue) start from the outside, or thin urethane cover, and extend inside to the ionomer boundary layer and tungsten-enhanced polybutadiene core which make up the three layers of the ball. First our scientists looked at the cover of the Rule 35 golf ball. The Rule 35 was already considered one of the best-performing golf balls on the market. However, Callaway Golf is always looking for ways to improve upon existing products, and through extensive testing at our Carlsbad, California headquarters, we knew there were things we could do to make it even better.

The result is the CTU 30 Red and Blue - a ball worthy of a new name that stands for the Cast Thermoset Urethane cover at a super-thin 0.030 inch. In fact, there is no thinner cover on the market today. A thinner cover allows for a larger core and greater ball velocity, so shots hang in the air longer, giving players the potential for increased overall distance. One of the secrets of the CTU 30 is that the urethane cover on the outside complements the synergy of the large core and ionomer boundary layer on the inside. The resilient rubber and ionomer of the first and second layers increase speed, and also decrease driver spin off the clubface - both attributes give players more potential distance. All that distance-energy is wrapped in an ultra-thin, soft urethane cover that "sticks" to the clubface for enhanced feel and the optimum amount of spin on shorter shots.

How does Callaway Golf get its CTU 30 cover so thin? The key is in casting. Our manufacturing team developed a proprietary process that allows us to make our cover among the thinnest in the world. Casting uses dimpled cavities in "molds" that are pre-injected with liquid urethane to cast the cover in two halves around the boundary layer-covered core of the ball. The cover material is a two-part mixture that reacts chemically to form urethane, and is fluid in consistency before curing. The fluid consistency allows the material to flow into the dimple cavities that make up the cover pattern, and when the liquid urethane is compressed around the interior layers and exposed to heat, it cures, cross-linking the molecules to form the very thin cast polyurethane cover of the ball.


	The new CTU 30 golf ball features a refined dimple pattern and more precise seam aesthetics for improved aerodynamic performance.

The CTU 30 Red construction is very similar to that of the Rule 35 Firmfeel in thickness and materials. The CTU 30 Blue has changes from the Rule 35 Softfeel, with a thinner cover and a little thinner boundary layer. That means the CTU 30 Blue has the same dimensions or material thickness in each layer as the CTU 30 Red. However, the firmness of each of the materials - from core to cover - is a bit softer in the CTU 30 Blue than in the CTU 30 Red, so the Blue model feels a little softer and spins a little more around the greens relative to the Red model.

We also developed better aesthetics around the seam - the parting line between the top and bottom halves of the tooling cavity or molds. Our scientists worked with our manufacturing engineers to develop a way to minimize the ball seam and move the dimples closer together around it by replacing the flash ring or "trough" with gates - small tabs that allow the excess urethane to flow from the cavity during the casting process. This allows more uniform dimple coverage, and thus improved consistency. Additionally, we improved the finish by making it glossier and more durable, so the ball looks even better out of the box and in play.

The overall result is a Demonstrably Superior and Pleasingly Different golf ball that delivers even greater performance - and more enjoyment - to golfers of all skill levels.

Odyssey White Hot 2-Ball Putter

At the Richard C. Helmstetter Test Center at Callaway Golf, our researchers, scientists and teaching pros work together to study the swing characteristics of players ranging from amateurs to top professionals. Much of that study is dedicated to putting, and our Putting Evaluation Center employs eight cameras to record a golfer's stance, ball position, eye position, putter path, and ball dynamics. The data is an invaluable tool not only in improving a player's swing, but also in our work to design and build putters to suit a wide variety of golfers' swing tendencies. A direct result of that hard work is the Odyssey 2-Ball Putter - a putter line with technological innovation unlike any other on the market today.

Since its introduction in late 2001, the 2-Ball Putter has become the No. 1 selling putter model in the U.S. as well as the No. 1 model in wins and usage across the world's six major professional tours combined. In fact, sales of the 2-Ball Putter have been so brisk that it would be among the top three putter companies in the U.S. if it were a stand-alone putter company. Now we've introduced more ways to even the score with 2-Ball Putter technology. The White Hot 2-Ball Mid and Long Putters have extended-length shafts for players who prefer "belly" or "broomstick"-style putters; they utilize the same unique alignment-enhancing design as the standard-length 2-Ball Putter. The DFX 2-Ball Putter is the first putter in the 2-Ball family to feature the reformulated Stronomic insert technology. Contact your nearest Callaway Golf retailer for details and availability. Here's the technical story behind this phenomenal putter line's success:

At Callaway Golf, our end goal is always the same - use technology to find new ways, improved ways, better ways - to bring more enjoyment to the game. Sinking a putt is pretty enjoyable in itself, and an improved short game is one of the fastest ways to lower your score. For example, if a player shoots 90 and has 36 putts - that's 40 percent of that player's overall score. So, in looking at new designs for our Odyssey putters, we asked: How can we help players consistently achieve good putts more often?

Two of the most common putting problems are distance-control and alignment. With our unique face insert technologies, we had already improved the feel and fine-tuned distance control, so then we went to work on the putterhead design to figure out how we could make shot alignment easier and more accurate.

A lot of past work has been focused on putterhead alignment aids, and a single alignment line or even two or three lines can be helpful to a point. But our testing showed that in some cases, when players line up over the putter and look at the hole, optics - or the way that a player's vision works - affect alignment and can "trick" the player into mis-aligning their shot. Some players learn to compensate for faulty optics over time, but in doing so they increase the chances of a missed putt.

In the 80s, a designer introduced a three-ball putter to the market, but it was deemed non-conforming by the USGA. It was in violation of Rule 4b in Appendix II of the Rules of Golf, which says that the distance from the heel to the toe of a club (in this case the putterface) must be greater than the distance from the face to the back. Basically - that means the head of the putter can't be wider than it is long. In response to this ruling, a new version of the design was introduced where the face was lengthened to conform with Rule 4b. However, this design was also ruled non-conforming because it violated Rule 4a in Appendix II, which states a club must be plain in shape. In recent years, Callaway Golf and Odyssey brand have worked to develop a new alignment design and consulted with the USGA to ensure that what ultimately became the 2-Ball Putter conformed to all rules.

So how does the 2-Ball Putter work? It makes alignment much easier by providing the visual of three golf balls in a row. The majority of golfers need a line at least two inches or longer to give them a reference point, but not just a straight line. The extended mallet design of the 2-Ball gives an optic of three balls when the two golf-ball-sized discs atop the putterhead are lined up behind the golf ball in play. This line of golf balls gives the player a more accurate preview of the true aim of the putter to help square the putter to target.

Our designers made the extended area under the discs hollow - that helps to properly position the center of gravity - while the sole design features recessed or concave areas on either side of a narrow "keel" down the middle for a consistently square set-up and a smooth stroke. Atop the putterhead, the alignment discs are made of injection molded polyurethane. They are secured onto the putterhead and specially painted.

In golf, it's the combination of the alignment and the path of the putter that dictates where the ball goes. The 2-Ball Putter is a good choice for beginning golfers to learn proper alignment, but - as its success on the world's professional tours has shown - the new design also works exceptionally well for professionals and top amateurs. Even the best golfers sometimes have trouble seeing the line - optics can change from day to day, and the 2-Ball Putter makes it much less likely that a player will make an alignment mistake. Talk to your pro or authorized Callaway Golf retailer about the 2-Ball Putter today - it's proven performance any way you line it up.

Fluid Dynamics and the HX Golf Ball

From Feathers and Leather to Next Generation Aerodynamics

In looking at the new Callaway Golf HX golf ball and how it offers superior aerodynamics, it's important to have a basic knowledge of the principles of fluid dynamics - which is the science of the movement of gases or liquids (that's air for our purposes) - as well as know a bit of the history behind the golf ball. So we'll start with a look at the original golf ball and its progress over several centuries, along with the advances in fluid dynamics and aerodynamics, which in turn will help explain efficiencies of the HX golf ball's revolutionary new Tubular Lattice Network and its resulting 100 percent surface area coverage.

The Featherie

In the 1400s, one of the earliest golf balls, known as the featherie, was developed by stuffing wet feathers into a wet leather pouch. The feathers dried and expanded; the leather pouch shrank and hardened. Back then, it was accepted that a smooth sphere would create less drag and therefore fly farther, so the leather was meticulously stitched inside out to minimize the seams - the best craftsmen could produce only three or four featheries a day.

In 1588, the heavily-armed, larger sailing ships of the Spanish Armada were outmaneuvered by the smaller, lighter English fleet of Sir Francis Drake and the study of fluid mechanics - how to reduce the water flow resistance on the hull of a ship and thus make it faster - began in earnest. Nearly a century later, Sir Isaac Newton devoted an entire volume of the Principia to fluid mechanics. While his model was not fully accurate, it was widely used in the 17th and 18th centuries and served to further promote the study of fluid flows. Much of that original knowledge led to the aerodynamic advances of today.

In about 1845, the first gutta-percha golf ball was made by heating and rolling the gum of a Malaysian Sapodilla tree into a sphere. It was more durable than the featherie, but didn't fly as far - until the smooth surface became scored or "dimpled" by the face of the golf club with repeated use. Soon, the gutta-percha was sold with a hammered surface to improve distance and accuracy, but the principles behind exactly how it worked remained murky.

With Reynolds Number, Air is a Wrap

The gutta-percha

In general, a golf ball is fighting a battle from the moment it leaves the clubface until the moment it lands. While the streamlined shape of an airplane, for instance, is designed to encourage the flow of air over its surface and create the lift necessary to help it fly, the golf ball, in its spherical, blunt-shaped beauty, creates a unique aerodynamic challenge. One of the most important principles in fluid dynamics is what's known as the Reynolds number - a physical measure of the ratio of inertia forces to viscous forces in fluid dynamics. With the help of Reynolds number, we now know that those first "dimples" on the gutta-percha were changing the flow of air over the surface of the golf ball from what's called laminar flow to turbulent flow. Think of smoke rising from a cigarette. At first it has a smooth flow (laminar,) before turning to an irregular, wider flow (turbulent.)

Laminar flow: Where the fluid element moves smoothly along parallel streamlines.
Turbulent flow: Where the fluid element moves in a random, irregular and twisting fashion.

The HX golf ball's improved aerodynamic efficiency creates a smaller wake and less drag.

During the flight of a smooth sphere, the air very near the surface remains in a laminar state over the front half of the sphere. As this laminar flow tries to close around the back half of the sphere, it "separates" from the surface, creating a large wake. Essentially, more air is being pulled along with the sphere rather than allowing the sphere to simply pass through it. This creates drag - a large wake of low pressure that slows the ball. By marking the surface of the ball with a pattern, it disturbs the airflow, and transitions it into a turbulent state. This turbulent air has more kinetic (motion) energy from mixing with the higher velocity air away from the surface of the ball. This higher level of energy allows the flow to remain attached to the surface of the ball longer, creating a smaller wake and less drag.

Building a Better Golf Ball

In 1887, British scientist P.G. Tait discovered that if backspin was applied to a golf ball, it created lift, which in turn helped the ball produce even more energy in order to hang in the air for a longer period of time. Then, on Dec. 17, 1903, the Wright brothers, after setting aside much of the conventionally accepted aerodynamic data, succeeded in the first powered aircraft flight, and the study of aerodynamics achieved more acceptance - and attention - than ever.

Much of that aviation knowledge was applied to other areas, including sports equipment, and by about 1930, the modern golf ball had evolved to what became the norm for much of the century - a rubber core wound with rubber threads and a dimpled cover - what's commonly called a wound golf ball.

Fast forward to 2000. Callaway Golf introduced its first solid-core, three-piece golf ball into the marketplace - the Rule 35. One outstanding feature of this ball was the improved aerodynamics efficiency of its new dimple pattern. Steve Ogg, a former Boeing engineer and our Senior Director of Golf Ball R&D, had figured out a way to reduce the flat area between the dimples - known as land area - and achieve 86 percent surface area coverage. That was a significant improvement over other golf balls, which typically had surface area coverage of about 75 percent. Less flat area on the Rule 35 - which was later refined to become the CTU 30 - when combined with optimized dimple cross sections resulted in low drag at high speeds, and high lift at low speeds.

This aerodynamic combination works well for the ball and the golfer, because less high-speed drag is great right off the clubface. It keeps the ball speed high for more distance. Then, after the ball reaches its apex, or highest point of flight, high lift at low speed kicks in. As the ball begins coming down, the lift helps keep the ball in the air and decreases its angle of descent, providing more carry and roll.

Maximizing Surface Area Coverage

But Ogg wasn't finished. While working to minimize the seam area - where the two halves of the tooling cavities or "molds" join to form the urethane cover of the ball - he took nearly a century of conventional aerodynamic thought on golf balls and turned it upside down. "What if there were no dimples, but instead a pattern of raised, interconnecting and rounded ridges that covered the surface of the ball?" he wondered. That would mean the seam would be significantly minimized, to give Callaway Golf's three-piece balls even greater consistency. As compared to conventional dimple patterns, it also would mean 100 percent surface area coverage. No flat area. Less high speed drag. More low speed lift. That means improved distance, better aerodynamics and a better golf ball called the HX.

The new HX golf ball, in a Blue model that is slightly softer for a bit more spin, and a Red model that is slightly firmer with a focus on distance, truly is the next generation of golf ball aerodynamics. This unprecedented golf ball builds upon the science, passion and innovation synonymous with the Callaway Golf name, and represents the spirit of Demonstrably Superior and Pleasingly Different thinking. Enjoy our next generation aerodynamics in the HX golf ball, and enjoy the game.