Tuesday, July 08, 2008

How Wow

For those who enjoy knowing the "big picture," this Web page is for you - How frisbee is made. For those who need reading material to induce a nap, read the same Web page.

Background: Nearly 300 million frisbees have been sold since their introduction 40 years ago, for both organized sports & recreational play. According to Mattel, 90% of Americans have played with this flying toy at one time or another, translating to 15 million people enjoying the sport every year. ...

Design: Manufacturers of frisbees use computer aided design software to create a model. A prototype is then made to test the design. ... Spinning the frisbee when it is thrown, or giving it angular momentum, provides it with stability. Angular momentum is a property of any spinning mass. Throwing a frisbee without any spin allows it to tumble to the ground. The momentum of the spin also gives it orientational stability, allowing the frisbee to receive a steady lift from the air as it passes through it. The faster the frisbee spins, the greater its stability. ...

Raw Materials: Frisbees have been made out of a thermoplastic material called polyethylene since the early 1950s. Polyethylene is the largest volume polymer consumed in the world. This material is derived from ethylene, a colorless, flammable gas. This gas is subjected to elevated temperatures and pressures in the presence of a catalyst, which converts the gas into a polymer. Other ingredients that may be added include colorants, lubricants, and chemicals to improve dimensional stability and crack resistance.

The Manufacturing Process: To make a frisbee, a high-speed process called injection molding is used, which is based on the injection of a fluid plastic material into a closed mold, usually of the multi-cavity type. Full diagram image. ...

Quality Control: The weight is one of the most important properties and is automatically controlled during the injection molding process by the screw on the machine that pushes the proper amount of material into the mold. ...

Byproducts/Waste: There is usually little waste produced during the manufacturing process. Sometimes after the frisbee is removed from the mold, it has excess material, called flash, around the edge. This is trimmed off, sent to a regrinding machine and then mixed with the virgin material. ...

The Future: The frisbee is expected to dominate the twenty-first century as one of the great sports & pastimes. Also, frisbee may some day be an Olympic sport. For a sport to be eligible for the Olympics, it must be played for two years in at least 50 countries. ... Ultimate Frisbee is already played in 35 countries and its popularity is growing, along with other frisbee sports.