Thermoforming VS. Injection Molding

The Process

Thermoforming

process graphic
Process Thermo Machine

Tooling

A single 3D form is created out of aluminum, wood, polyurethane or 3D Print.

Materials

Flat sheets of thermoplastic, available in a wide variety of materials, finishes, colors, and thicknesses.

Production

A flat sheet of plastic is heated to a pliable temperature, then molded to the tool’s shape using either suction from a vacuum or both suction and pressure.

Finishing

The final pieces are trimmed robotically, then can be used uncoated, or painted, silk-screened or have specialty coatings applied.

Injection Molding

Process Graphic

Tooling

A double-sided 3D mold is created out of steel, aluminum or a beryllium-copper alloy.

Materials

Thermoplastic Pellets, available in a wide variety of materials and colors.

Production

Plastic pellets are heated to a liquid state, then injected into the mold.

Finishing

The final pieces are removed from the mold, then often need to be painted for aesthetic reasons, and can also be silk-screened or have specialty coatings.

Process Injection Machine

The Cost

Thermoforming

Tooling Cost

Per-piece Production Cost

Injection Molding

money right

Tooling VS. Production Costs

Single-sided thermoforming tooling is a considerably cheaper process than creating a double-sided mold used in injection molding. But, the cost of each individual part formed by Injection Molding is generally less expensive.

Cost Comparison - Sample 48” x 60” Part

Cost Graph

The break-even point will vary with every project, typically between 2,000 and 5,000 parts. Smaller parts will have a lower break-even point and vice versa for larger parts.

Lead Time

Thermoforming

14 Weeks

8 WEEKS OF TOOLING | 6 WEEKS OF PRODUCTION

Injection Molding

24 Weeks

16 WEEKS OF TOOLING | 8 WEEKS OF PRODUCTION

Other Considerations

Thermoforming

Considerations

Does it allow variable thickness within a single part?

How does it look unpainted?

How large of a part can it reasonably produce?

Injection Molding

Considerations

Needs Comparison

Thermoforming

best for

Part Size

Creating large parts up to 10’ x 18’, and
consolidating multiple parts into a single large part.

Run Size

Creating small to medium (100 - 3,000) runs of parts.

Aesthetics

Aesthetically pleasing parts with minimal secondary operations.

Injection Molding

best for

Part Size

Creating small parts with minimal consolidation

Run Size

Creating large runs (3,000+) of small to medium sized parts.

Aesthetics

Creating parts with variable thickness in a single part.

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