How Are Bowling Balls Made?. By: Jacqueline Philp & Cienna Ribblett. Raw Materials. Urethane A form of carbonic acid Plastic Polymers of isoprene units and other natural materials Reactive Resin A material made of Urethane and natural Resin Wood Lignum vitae. What they were Made of.
By: Jacqueline Philp & Cienna Ribblett
1. A mold is formed to the core shape developed during the computerized design process. The appropriate material is poured into the core mold and left to harden. The solid core is removed from its mold.
2. Sometimes there is a second step to finish the core. For example, some ceramic cores are fired in a kiln. Compound cores are formed by inserting the first core into a second mold and pouring material of a different density around it.
3. The core is placed inside a spherical mold called the cover mold. The core is attached to a pin that points in from the shell of the mold. The pin holds the core in the right position. If the pin points toward the center of the mold the core is pin in. If it is tilted away from the center the core is pin out.
4. The cover material is poured into the mold, encasing the core, and is left to harden. The thickness of the cover may be as little as 1 inch or as much as 2 inches depending on the design of the particular ball.
5. When the ball is removed from the cover mold, there is a hole where the core-holding pin had been. A plastic dowel is inserted into the hole and cemented in place. The pin is a different color than the cover. After the ball has been bought, the pin will be used as a guide for positioning the finger holes to take advantage of the core’s design.
6. Fill material is added to the logo imprint that was molded into the ball. The logo is located at the top of the ball.
7. The ball is finished to the right size by turning it on a lathe (a machine used for cutting, drilling, sanding, or shaving) and shaving off enough cover to get the right shape or it may be done on a center less grinder that scours (cutting the ball down) the ball into the right size and roundness.
8. Finally, the surface of the ball is finished to the right texture. It is sanded to an appropriate degree of polish, expressed by the roughness of the sanding material.
9. The ball is boxed and shipped to the company's distributor. And that is how they make bowling balls.