For years the term “Vacuum Forming” was used to describe how our industry molded parts. Vacuum Forming involves stretching a hot sheet of plastic over a mold. The material is then pulled tightly to the mold configuration using a vacuum. As it cools, the plastic product takes shape. Vacuum forming is effective when producing large parts, and offers low-cost tooling and quick prototyping.
Over the years the process has evolved, and today it is referred to as “Thermoforming”. Many in the industry still mold using straight vacuum forming but those of us committed to providing the best possible part at the lowest cost have embraced pressure forming.
Thin-Gauge Thermoforming – Is primarily the manufacture of what are referred to as Clamshells, Blisters and Trays for the Medical, Food and Retail markets. These thin-gauge parts are typically formed with a starting material thickness of .005 to .060. Thin-gauge materials are usually delivered to the thermoforming machine from rolls. Thin-gauge parts are most often designed for single use and can almost always be recycled.
Heavy-Gauge Thermoforming – Parts requiring a sheet thickness greater than .060 are typically considered heavy-gauge. Sheets are delivered to the forming machine by hand, or in some cases an auto-feed method is used. Heavy, or thick-gauge, thermoforming applications are primarily used for more long lasting or permanent structural components such as Radomes, Automobile Parts, Medical Housings, Material Handling Systems and Electronic Housings. Unlike most thin-gauge thermoformed parts, heavy-gauge parts often undergo “secondary operations after forming for trimming to final shape or for additional drilling, cutting, or finishing, depending on the product. This work is often done using CNC machines but hand-worked secondaries are not uncommon.