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Vacuum Forming Machines
What does it do ?
“Vacuum Forming” or “Thermoforming” is a simple process where you take a flat plastic sheet, and heat it until it’s soft. Then you stretch it over a mold or pattern, and suck it down tightly with vacuum. The plastic cools quickly and retains that shape. Vacuum forming is ideal whenever you need a “shell” type plastic part with uniform wall thickness. You can form over wood, plaster and many other materials. (See sample parts below…
How Does it Work?
Lets go through the process, (refer to the drawing above). Clip a plastic sheet into the carrier frame and raise the lift handle until it locks. This raises the plastic to the overhead oven where it will heat until it gets soft. Place your mold or pattern anywhere on the perforated forming surface below, (also called the Platen). When the plastic has the correct amount of sag or droop, its ready to form. Lower the handle to bring the soft plastic down and stretch it over your mold. When the handle is all the way down, open the dump valve to release the stored vacuum and suck the plastic down tightly. The plastic cools quickly and the part can be removed. Load another sheet and do it again. The typical cycle time ranges from 1 to 5 minutes depending on plastic thickness. Form up to 1/4 inch thick sheets!)