Plastic gears are mainly manufactured using injection molding, which is suitable for mass production. A small number of precision gears can also be manufactured using CNC machining or 3D printing.
Injection Molding
This is the most mainstream and economical mass production method.
• Process: Plastic granules are heated and melted, then injected under high pressure into the cavity of a precision gear mold. After holding the pressure and cooling, the mold is demolded to obtain the gear product.
• Applicable Materials: Engineering plastics such as POM (Polyoxymethylene), PA (Nylon, such as PA66), PC (Polycarbonate), and PP (Polypropylene).
• Features: Extremely high efficiency, low cost, good consistency, and capable of molding complex tooth structures. Mold development costs are high; suitable for orders exceeding 10,000 pieces.
CNC Milling/Turning
Used for prototyping, small-batch production, or mold repair.
• Process: Using a CNC machine tool to cut plastic rods or sheets.
• Features: No mold required, high flexibility, high precision (up to ISO 8 or higher), but high unit cost and low material utilization.
3D Printing (Additive Manufacturing)
Primarily used for design verification, functional testing, or very small batch customization.
• Processes: SLA (Stereolithography), SLS (Selective Laser Sintering), FDM (Fused Deposition Modeling), etc.
• Characteristics: No mold costs; can manufacture extremely complex internal structures; however, the mechanical strength and wear resistance of gears are generally lower than injection-molded parts; surface texture requires post-processing.
