This is a highly common and efficient rapid tooling method, particularly suitable for producing small batches (typically from a few to dozens of units) of plastic prototypes or parts with high precision and intricate details.
Core Concept: What is a Silicone Mold?
A silicone mold refers to a flexible mold with a cavity, formed by pouring liquid silicone rubber over a master pattern (original prototype) and allowing it to cure. This cavity perfectly replicates the shape and details of the master pattern. Another material (such as polyurethane resin, epoxy resin, low-melting-point alloys, etc.) can then be poured into this cavity to reproduce multiple copies identical to the master pattern.
Why Choose Silicone Molding?
Advantages:
High Replication Accuracy: Capable of perfectly reproducing fine details of the master pattern, including extremely subtle textures, engravings, and complex structures.
Easy Demolding: The excellent flexibility of silicone allows for easy part removal by bending the mold, even for products with undercut structures, which is impossible with steel or aluminum molds.
Short Lead Time and Low Cost: Compared to expensive metal molds, silicone molds are very simple to make, take little time (typically 1-2 days), and are extremely low cost, making them ideal for the product development and verification stage.
Wide Range of Compatible Materials: Can be used with various two-component liquid materials, most commonly polyurethane (PU) resin, which can simulate the strength, hardness, and color of many engineering plastics (e.g., ABS, PP, PC, Nylon).
Easy to Operate: Does not require large, professional equipment and can be done in a lab or workshop environment.
Disadvantages:
Limited Lifespan: A single silicone mold can typically only produce 20-50 parts (depending on mold complexity and casting material). After this, aging and tearing cause a loss of precision, making it unsuitable for mass production.
Limited Temperature Resistance: Standard silicone can generally withstand temperatures below 200°C – 300°C and cannot be used for injecting high-temperature molten thermoplastics (like ABS pellets for injection molding machines).
Low Production Efficiency: Each casting cycle requires manual operation and a certain curing time. It is a typical “labor-intensive” process and cannot compare to the high-speed automation of injection molding machines.