Thermoforming vs Injection Molding
There is a lot of speculation on thermoforming vs injection molding. In this article, we will be going over the difference in process, cost, lead time and all other considerations.
The Process
Thermoforming
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
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.
The Cost
Thermoforming
Tooling Cost
Per-piece Production Cost
Injection Molding
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
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
8 WEEKS OF TOOLING | 6 WEEKS OF PRODUCTION
Injection Molding
16 WEEKS OF TOOLING | 8 WEEKS OF PRODUCTION
Other Considerations
Thermoforming
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
Needs Comparison
Thermoforming
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
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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Whatever your manufacturing needs may be, Global Thermoforming can put our engineering, design, and manufacturing expertise to work for you.
