Tennis balls typically use natural air pressure for inflation. This method gives many of the premium and Championship line balls sold by Tennis Warehouse their signature bounce.
“Pressureless” balls feature heavier structures without an internal air pressure source, making them less buoyant than their pressurized counterparts but still capable of jumping thanks to rubber frame structures.
Felt
Felt is a non-woven material composed of short fibers that is used for manufacturing tennis balls. With its fluffy surface, felt makes it easier for tennis players to strike the ball with a racket while helping it bounce off different surfaces with precision – this is essential when considering that various playing surfaces affect aerodynamics in different ways, which would otherwise prevent an otherwise airtight tennis ball from performing optimally across different playing surfaces. Without felt, tennis balls would struggle bouncing correctly over different surfaces.
Manufacturing involves punching felt with needles to achieve the desired shape and then heating it to soften its materials. After that, it is attached to the outer periphery of a crosslinked rubber core which has been coated with an ion-exchange resin to provide extra flexibility resulting in an elastic ball with great elasticity in all directions.
After being sanded to remove any rough spots and sealed to ensure waterproofness, the balls are then assembled by pressing them together and inflating to their respective air pressure levels before being sanitised and packed into pressurised cans for packaging – ready to play!
Even with all of the technological advancements involved in making tennis balls, it still takes hard work to craft an exceptional tennis ball. A team of engineers and science graduates work diligently to make sure these little things perform consistently each time – or else a grand slam winner could lose their title!
Professional tennis players understand that even one small misstep can throw their entire game off balance, which is why they employ only high-grade materials and processes when producing superior tennis balls. Wilson utilizes an exceptional woven felt composed of two thirds wool and one third nylon for its superior tennis balls, as the wool helps the ball return more quickly to its original position than nylon does – essential to performance! Furthermore, wool boasts superior heat and water resistance compared to nylon; therefore being better equipped to withstand tough court conditions; furthermore it feels better when wet – making it an invaluable advantage over nylon when used by professionals!
Rubber
Rubber used to manufacture tennis balls is typically composed of both natural and synthetic materials, typically including polybutadienes. This material offers excellent flexibility, durability and satisfying feel when hit by a racket; additionally it boasts good rebound properties after every strike as well as withstanding repeated impacts. Vulcanization technology is employed during its production; heating of the rubber then molding and pressing into flat sheets are used before being rolled into hemisphere shapes to form core of balls using glueing processes.
The outer felt layer of a ball is composed of both natural and synthetic materials, designed to be resilient against wear. For extra protection and increased abrasion resistance, additional coating can be added or it may even be dyed to give each ball its unique hue.
Inner core rubber composition typically includes sulfur or an organic sulfur curing agent; one or more curing accelerators such as thiazole compounds, sulfenamide compounds or guanidine compounds; inorganic fillers like basic magnesium carbonate, hard clays, precipitated calcium carbonates precipitated calcium carbonates precipitated cellulose powder or white carbon (silica). Hollow core rubber mixture is then kneaded together and compressed at 160 kg/cm2 into two half-spheres in accordance with standard operating procedure for pressurized or pressureless tennis balls manufacturing processes.
Melton covers are applied to each hemisphere and vary depending on the type of ball; depending on its composition, they could include wool or nylon fibers for durability and feel; premium balls use more natural wool fibers to give extra durability and an improved feel, fluffier surface to increase resilience over repeated impacts, as well as providing consistent bounce after multiple impacts. Finally, each ball goes through a quality control process which includes testing its size, weight, pressure and curved seam.
Core
Pressurisation is key for tennis ball bouncing; that is what creates its trademark “pop” sound when they hit your strings. Most premium balls (such as those offered by Tennis Warehouse) contain compressed air which combines with their rubber core to give these tennis balls their high, satisfying bounce.
A tennis ball’s rubber core is composed of various materials. Some are natural such as latex from rubber trees; others are synthetic such as polybutylene terephthalate (PBT), an extremely strong yet flexible material which holds its shape without distortion from impact of hitting an object with it. Furthermore, its highly elastic properties enable it to absorb impact energy before channeling it back outward in other forms such as gymnast hip whipping.
Once rubber has been formed, it is shaped into two half-shells and sealed together using adhesives. Next comes rigorous testing by the International Tennis Federation that measures rebound, forward and return compression rates as well as weight of ball.
Wilson’s double-core tennis ball innovation has proven particularly successful over time, using clay nanoparticles to prevent air leakage and create an ultra-durable tennis ball which lasts twice as long as regular balls.
Other companies have developed innovative methods of recycling used tennis balls. One, Advanced Polymer Technology, has created a machine that converts old tennis balls into soft but durable material; and Ace Surfaces developed a system for turning recycled tennis balls into felt for sports courts.
These innovations not only reduce waste produced by the tennis ball industry, but are also improving its quality for people of all ages. Durable and easier-to-grip tennis balls help children develop hand-eye coordination and motor skills more easily; plus they can be used during high intensity interval training workouts to promote heart health and endurance.
Weight
Weight plays an integral part in tennis ball performance. A heavier ball will move more slowly than its lighter counterpart; though the difference might not be obvious to casual recreational players, its effect can have profound ramifications on serves or long baseline rallies.
Tennis players frequently change up their ball choices depending on the surface they are playing on, with professional matches typically using more specialized balls than what can be purchased by members of the general public. This is because the ITF provides strict guidelines regarding size, shape and weight standards of their tennis balls – most players adhere to them faithfully.
ITF regulations specify that tennis balls must be spherical with diameters between 2.57 inches (6.54 cm) and 2.70 inches (6.86 cm). They allow some variance depending on type; an extra duty ball would typically be designed for hard court surfaces while regular duty balls typically feature stain resistant features essential for grass and clay courts.
Small variances in diameter and weight variations are important because they help ensure consistency within a game. For instance, using tennis balls of uniform size and weight will allow players to quickly assess how much power each swing of their racket generates.
One factor affecting a tennis ball’s weight is how it’s manufactured. Typically, its rubber core is produced first before adding felt as an outer layer – and this combination is then fused using intense heat and pressure through a process known as “vulcanizing.” Vulcanization creates a tough shell protecting its inner ball from damage.
For those not looking to invest in professionally made tennis balls, a wide range of practice tennis balls is also available for sale. These tend to be less costly than ITF approved ones while still providing adequate performance; unlike pressurized balls used in official tournaments that lose air pressure over time, practice tennis balls rely on thick rubber shells instead for their bounce retention.