Benedict Redgrove filmed the tennis ball production process in a factory in Thailand. The video details the 24 steps ending in a bouncy, lightning-yellow wool covered ball.
See the entire process in the video below:
How to Make a Tennis Ball from Benedict Redgrove on Vimeo.
The entire process starts off with the natural rubber-based core compound that is crushed for five minutes. The core compound for the tennis ball is then cut into barrel-shaped slugs. Each slug is used to shape the half shell of a tennis ball. The slugs are then transformed into a very thin half shell.
The moulded half shells are removed using an air gun. The half-shell sheets are allowed to cool. A blue adhesive is applied to the seams of the cooled and trimmed half shells.
The cores of the tennis balls are placed in the tumbling machines for the application of white glue. The stacks of optic yellow felt are placed in clamps for application of the white glue, which appears as a white seam on the ball.
The felt panel applied to the tennis ball is only an eight of an inch thick.
The balls are then packed inside pressurised cans to prevent them from losing air.