Thermoform Molding

Thermoforming is shaping a heated thermoplastic sheet over a mold, then cooling and trimming it into a finished part.
 • It starts with flat plastic sheet (thermoplastic means it softens with heat and hardens again when cooled).
 • The sheet is formed using vacuum, air pressure, or matched tooling, then trimmed to final edges/features.
 • It’s a process family that includes vacuum forming, pressure forming, and twin-sheet forming.

Vacuum forming is a type of thermoforming that uses suction to pull a heated plastic sheet onto a single-sided mold.
 • The mold can be “male” (sheet pulled over) or “female” (sheet pulled into).
 • Vacuum forming is often chosen when one show-surface needs the most control and the opposite side can be less precise.

Typical steps are: clamp, heat, form with vacuum, cool, release, trim, and inspect.
 • Clamp: hold sheet flat and sealed.
 • Heat: bring sheet to a formable temperature window.
 • Form: pull sheet to the mold using vacuum.
 • Cool + release: set the shape, then remove safely.
 • Trim + inspect: cut openings/edges and verify critical features.

A thermoforming machine clamps and heats plastic sheet, forms it over tooling using vacuum and/or air pressure (and sometimes plug assists), then cools and sends parts to trimming.
 • Thermoforming machines can be set up for different forming styles: vacuum, pressure, twin-sheet, and matched tooling variants.
 • Trimming may be inline or done as a secondary step (for example, CNC trimming for complex edges/openings).

You pick the plastic that meets your strength, surface, temperature, chemical-resistance, and cost targets; ABS is common for durable housings, while polycarbonate is used when higher impact performance and heat resistance are needed.
 • ABS: often chosen for toughness and a good balance of cost and finish.
 • Polycarbonate (PC): often chosen when higher impact performance and heat resistance matter.
 • TPO: often used where flexibility and weathering performance are priorities.
 • Polyethylene family (including higher-molecular-weight grades): often used where abrasion/chemical resistance and toughness are needed.