Creating Parts of the Ball
Whether they are solid rubber or filled with air, rubber balls are generally constructed in multiple parts which are then attached to each other (though some smaller rubber balls may be molded whole). These parts are most commonly created in rubber molds, often through an injection molding process, although some ball parts may be created by the cutting of larger rubber sheets or other mechanical processes. Once the parts have been made and removed from their molds or similar machinery, they are loaded onto conveyor belts or placed into bins so that they can be transported to begin the next part of the process.
Preparing the Ball Parts
Because of the rough edges and uneven seams that can occur when molding rubber for rubber balls, many of the parts of balls will need to be cut free from excess rubber and have uneven sections removed. Depending on the type of rubber ball being made, this may be done automatically by a buffing machine or manually by having workers trim and buff the rubber as needed. These preparations are generally minor and take only a small amount of time to finish before the balls are sent to be finished.
Finishing the Ball
Parts of unfinished rubber balls may be attached using glue or by heating the rubber in order to melt a small portion and "welding" the parts together. Regardless of the method used to attach the parts of the ball, the parts must be matched up carefully and quickly in order to have a round and solid ball without a weak seam. Hollow rubber balls need to have an air plug inserted into them after the glue or melted rubber dries so that they can be inflated; solid rubber balls simply need to be prepared so they can be packaged for shipping. Depending on the type of balls being produced, they may need to be painted or printed upon before being packaged.
- Colourful rubber balls isolated on white (with clipping path) image by Marek Kosmal from Fotolia.com