How Is Tennis Ball Made?
Contents
Check out this blog to learn about how a tennis ball is made. You will be surprised at the process and the amount of detail that goes into making this small, yet essential piece of equipment for the game of tennis.
Materials
Tennis balls are made of four basic parts: the core, the windings, the felt, and the cover. The core of a tennis ball is made of solid or hollow rubber. The rubber is the part of the ball that bounces. It is also the heaviest part of the ball. The windings are the strings that are wrapped around the rubber core. They are made of nylon or natural gut. The felt is made of wool or synthetic fibers. It is glued or stitched to the windings. The cover is made of rubber or synthetic materials. It is glued or stitched to the felt.
Rubber
The core of a tennis ball is made of rubber. The type of rubber used affects the feel, bounce and durability of the ball. A natural rubber compound is generally used for high-end, professional-grade balls, while a synthetic rubber compound is typically used for practice balls. The covering or “jacket” of the ball is also made of rubber. Once the core and jacket have been formed, they are vulcanized, or hardened, using heat and chemicals.
Felt
Felt is a textile fabric that is produced by matting, condensing and pressing fibers together. Felt has been around for centuries and is used in a variety of applications, from clothing and jewelry to wall coverings and flooring. The tennis ball you purchase at the store is made of felt, which is necessary to create the bouncing effect when the ball hits the ground.
The fibers that are used to make felt can be natural or synthetic. Common natural fibers used to make felt include wool, cashmere, rabbit fur and alpaca wool. Synthetic fibers often used in felt making include acrylic, polyester and nylon.
To make felt, the chosen fibers are first loose and tangled together. They are then fed into a machine called a felting machine which uses needles to comb through the fibers, matting them together as it goes. The matted fibers are then condensed using steam or heat until they bond together to form a sheet of fabric.
The Manufacturing Process
The tennis ball is one of the most popular balls in the world. It is used in a variety of sports including tennis, badminton, and squash. It is also a popular toy for dogs. The tennis ball is made from a variety of materials including rubber, felt, and nylon. The manufacturing process of the tennis ball is quite interesting.
vulcanization
The vulcanization process was invented in 1839 by Charles Goodyear, and it is this process that gives modern-day rubber its strength and elasticity. In vulcanization, sulfur or other curatives are added to the rubber compound, and the mixture is then heated to bond the components together. Vulcanized rubber is also less susceptible to changes in temperature, which means it can be used in a much wider range of applications than un-vulcanized rubber.
Molding
The third and final stage of making a tennis ball is molding. The rubber is placed in a mold that gives the ball its shape. The mold is heated until the rubber is soft, and then the mold is cooled so the rubber hardens again. This process takes only a few minutes.
Curing
The next step is cure, where the rubber is heated and cooled to make it more durable. Unvulcanized rubber is heated in a furnace with sulfur. The sulfur molecules bond with the molecules in the rubber, a process called vulcanization. This makes the rubber stronger and more heat resistant. After this step, the rubber is still not ready to be made into a ball. It needs to be vulcanized again, but this time with other materials to give it extra strength.
Quality Control
The journey of a tennis ball begins with the sourcing of raw materials. The main component of a tennis ball is rubber. The rubber is first vulcanized, or heated, to make it stronger. It is then cut into small pieces and sent to a factory.
Standards
There are four USTTA-approved ball brands, and each brand manufactures four types of balls. The four types of balls are differentiated by their bounce. The three regular ball types have a bounce between 53 and 58 inches when dropped from a height of 100 inches onto a concrete surface. A “slow” ball has a bounce of 50-53 inches.
Balls are shipped in pressurized cans to ensure they retain their elasticity. When tennis balls become old and lose their bounce, this is referred to as “going dead”.
The United States Tennis Association (USTA) has developed a standard for tennis balls that all balls must meet in order to be used in USTA-sanctioned events. In order to meet the standard, balls must have certain physical and performance characteristics, including weight, size, deformation, and bounciness.
To test for weight, each ball is weighed individually on an electronic scale accurate to within 0.1 grams. The minimum weight for a tennis ball is 56 grams, and the maximum weight is 58 grams.
To test for size, each ball is placed on a measuring device called a deflectometer which measures the diameter of the ball to within 0.005 inches accuracy. The minimum diameter for a tennis ball is 2.575 inches, and the maximum diameter is 2 625 inches.
To test for deformation, each ball is placed in what is called a deformatter which subjects the ball to high amounts of pressure. The percentage of deformation allowed for USTA-approved balls is 21 percent or less. As the amount of deformation increases, so does the level of play required for using that particular type of ball – meaning that if you want to improve your game, you should try using higher quality balls that deform less under pressure!
Lastly, to test for bounciness or rebound elasticity, each ball is dropped from a height of 100 inches onto a concrete surface – with 53-58 being ideal for tournament play according to the USTA guidelines.
Testing
To ensure a high level of quality, all tennis balls must undergo a series of tests before they are approved for sale. The first test is the bounce test, which measure the height of the ball’s bounce. Next, the hardness test ensures that the ball is not too soft or too hard. Finally, the stitching test checks to see that the ball’s seams are strong enough to withstand repeated hits.
