How Much Extra Does Double Shot Molding Add to Each Part?

Double shot molding does not have a universal per-part surcharge. The added cost is determined by the two-color mold design, material pairing, cavity configuration, validation work, and the production volume used to spread the tooling investment. A project-specific quotation is therefore required to establish the actual increase.

What Drives the Added Cost?

Unlike conventional single-material injection molding, double shot molding completes two injection stages within one mold system. This process supports combinations such as ABS with TPU or PP with TPE, allowing manufacturers to combine rigid and flexible features in one component.

The main cost variables include the precision required for alignment, the selected cavity arrangement, the complexity of the mold structure, the chosen materials, and the expected order quantity. Multi-cavity tooling may require a higher initial investment, but it can improve output and reduce the tooling allocation assigned to each part during larger production runs.

• Two-color tooling and precision alignment contribute to the initial mold cost.
• Material prices vary between combinations such as ABS+TPU and PP+TPE.
• Trial molding, dimensional checks, and pre-shipment inspection add manufacturing activities.
• Higher production volumes can distribute tooling expenditure over more finished parts.

Tooling Life and Cost Allocation

The listed mold construction uses 718H / 1.2738 steel and is rated for a service life of up to 800,000 shots. This capacity can help lower the tooling amount assigned to each part when the mold is used for a substantial production program. In contrast, a small order may carry a larger share of the mold investment per unit.

The service-life figure should not be treated as a guaranteed per-part price calculation. The available information does not state the mold quotation, material rates, injection cycle time, expected scrap rate, or amortization method. These details must be confirmed for each product before the additional unit cost can be calculated.

Validation, Inspection, and Production Planning

Double shot projects generally include mold trial runs and sample evaluation before production approval. The listed quality activities include dimensional testing and pre-shipment inspection. These steps should be included in a total-cost comparison because they require engineering time, equipment, and production planning.

Longterm's stated process allows sample approval before mass production, while the mass-production quantity remains negotiable. The final unit economics will depend on whether the tooling is used for a short pilot run, a moderate batch, or a long-term production schedule.

Project Experience

Longterm Mold has completed a double shot overmolding mold project for a French product brand. The application involved a consumer electronics shell, and the reported trial results showed good alignment and stable samples. This example demonstrates relevant experience in validating two-color tooling, although it does not disclose a specific per-part surcharge.

Cost Factors at a Glance

Frequently Asked Questions

Is double shot molding always more expensive per part?

There is no fixed answer from the supplied data. The process can involve additional tooling, alignment control, material handling, and inspection compared with single-material molding, but the actual unit difference depends on the complete project configuration.

What information is needed for an accurate quotation?

Provide the part geometry, hard-and-soft material combination, mold structure, cavity plan, target quantity, inspection requirements, and confirmation of whether mass production will follow sample approval. These inputs allow the supplier to evaluate both tooling and recurring production costs.

Will a larger order lower the tooling cost per unit?

Usually, yes. A larger production quantity spreads the mold investment across more parts. The listed tool life is up to 800,000 shots, but this specification does not itself establish a guaranteed amortized unit cost.

Conclusion

The extra cost of double shot molding generally comes from the two-color mold, precision alignment, selected materials, cavity configuration, trial and inspection requirements, and the volume over which the tooling investment is allocated. To obtain a reliable figure, request a quotation based on the part design, material pairing, cavity requirements, forecast quantity, and approval plan. Longterm provides custom mold making, injection molding, mold development, and plastic injection mass production. For technical assistance, contact rogerluo@longterm-mold.com.

About Longterm Mold

Longterm Manufacturing Solutions Limited, known as Longterm Mold, was established in 2010 and serves international customers with mold design, tooling, precision machining, mold manufacturing, and parts production. The company employs 50 people and operates from a 2,000sqm factory. Its R&D engineers work on injection mold structural design, precision CNC components, sample validation, and process improvement. Longterm holds ISO 9001:2015 certification covering the design, manufacture, and sale of precision molds and the sale of plastic products, with experience across several industries.