Thermoforming vs Injection Molding
Many parts that are currently being injection molded could also be thermoformed.
Thermoforming is a preferred solution in many cases, such as when
Parts are large
Short lead time is required
Unsure of the viability of the product or unsure of sales volume
Likely that the design will change
Need to minimize startup costs
The following table provides some points to consider.
Thermoforming
Ideal Volume: Up To 10,000 (varies by part characteristics)
Minimum Lot Size: 10
Lead Time: As little as 1-3 weeks
Tooling Cost: $500+ depending on material.
Mold Construction: Various composites, aluminum or sometimes wood.
Amortization Of Tooling: 100-5,000 parts.
Design Changes: Composite or aluminum tooling is quickly reworked and lower tooling costs mean less financial risk.
Part Size: Ideal for large parts
Appearance: One surface of plastic is completely untouched (for one-part molds), and thus generally has no defects. Surface in contact with mold offers excellent detail based on mold. The application will determine which is the finished side.
Injection
Ideal Volume: 1,000+
Minimum Lot Size: 1,000
Lead Time: 20+ weeks
Tooling Cost: $25,000 – $100,000
Mold Construction: Steel
Amortization Of Tooling: 1,000-100,000 parts.
Design Changes: Steel tooling requires longer turnaround, and changes could require new tooling at substantial costs.
Part Size: Large parts can have prohibitively expensive tooling and unit costs.
Appearance: Injection marks, gate marks and porosity can be an issue.