Low Volume Manufacturing

Injection molding has traditionally been cost-effective for high-volume production due to its ability to generate large quantities quickly. However, the initial high cost of tooling has deterred its use for low-volume production. Additionally, the rise of 3D printing, with its affordability and widespread availability, has overshadowed injection molding in certain cases, making it less attractive for smaller production runs.

Injection molding has emerged as a reliable and economical option for small production runs, offering a broader range of materials than 3D printing. Materials like polypropylene, Santoprene, and glass-filled nylon are available, and mixing is possible. Popular materials for mold production include P20 steel and aluminum, while silicone and rubber are suitable for low-volume molds, reducing costs significantly for small batches.

Molds can accommodate multiple cavities, forming what’s known as a ‘family’ or multi-cavity mold, which reduces production costs by allowing more parts to be made from one mold. This design also enables different parts of the final product to be produced in the same mold. Single cavity molds are typically cheaper and may be preferable for very low-volume production of a single item.

Before mold production, the quality of the CAD file used for the mold design is crucial. A Design for Manufacture (DFM) document can highlight design strengths and weaknesses, suggesting improvements for a better-quality product. Flow lines from inadequate gate placement can affect the appearance of the part. A skilled mold engineer can address these issues using Mold Flow Analysis (MFA) to ensure the final part meets the highest standards.