1. Mr. Thomas Thermoforming Processes CCHS Plastics Technology

2. Thermoforming Process Thermoforming is an ancient technique involves heating plastics materials and forming them around a desired mold or shape. Thermoforming is an ancient technique involves heating plastics materials and forming them around a desired mold or shape. It was first used in animal horns and tortoise shells. It was first used in animal horns and tortoise shells. –Thermo = heat –Forming = to mold into a desired shape

3. Thermoforming Process Thermoforming processes utilize three different types of force: Thermoforming processes utilize three different types of force: 1. Mechanical 2. Air 3. Vacuum

4. Thermoforming Products Thermoforming is a versatile process that is used to produce many types of products including: Thermoforming is a versatile process that is used to produce many types of products including: –Trays –Signs –Toys –Food Packaging –House wares

5. Thermoforming Products

6. Straight Vacuum Forming The most versatile and widely used type of thermoforming The most versatile and widely used type of thermoforming The type of thermoforming we will do in class. The type of thermoforming we will do in class.

7. Steps to Vacuum Forming 1. A plastic sheet (styrene) is clamped in a frame 2. The plastic sheet is heated by a heating element 3. When the plastic become soft, a mold is pressed into the plastic either by mechanical force or atmospheric pressure 4. Air is removed from the mold by a vacuum 5. After cooling the part is removed from the machine

8. Advantages of Vacuum Forming Low tooling costs Low tooling costs Good dimensional accuracy Good dimensional accuracy Parts with large surface areas can be produced economically Parts with large surface areas can be produced economically Short production runs and prototypes are practical Short production runs and prototypes are practical

9. Disadvantages of Vacuum Forming Thinning on edges and in corners of product Thinning on edges and in corners of product Wasted material due to excess scrap or flashing Wasted material due to excess scrap or flashing