An overview of Two-Shot Injection Molding & Overmolding
2024-01-09 10:31:45
Two-shot injection molding and overmolding are advanced injection molding techniques that involve the use of multiple materials or colors in a single molding process. Two-shot molding Two-shot injection molding, also known as dual-shot or multi-shot molding, involves injecting two different materials into the same mold in two consecutive steps. Through the different layers of materials or colors created by the injection molding machine, the first material is injected into the mold to create the substrate, and other materials or materials will be molded around the substrate. After the substrate solidifies and cools, it is transferred by hand, robotic arm, or rotating plane to another cavity of the mold. This process combines different materials or colors within a single, integrated part. Two-shot molding is an ideal process for complex, multi-material, and multi-colored plastic products; specifically in high-volume production. Other advantages include:
Improved part functionality with different material properties.
Reduced assembly steps and costs.
Enhanced design flexibility for complex geometries.
Overmolding Overmolding involves molding one material over another, creating a layered or sandwiched structure. This process is regularly used to manufacture sub-sections of parts and for prototype development. Typically, the substrate material is placed into an injection molding tool, at which point the over-molding material is shot into or around the substrate. When the overmold materials solidify, the two materials become joined together as a single part. If you are overmolding a metal part with plastic, you can really use any type of plastic. If you are overmolding a plastic part with another plastic, then there can be some compatibility issues. Your experienced molder will be able to recommend the best materials suitable for your project. Overmolding is commonly used for adding a soft, tactile grip to handles or tools, encapsulating electronics, and creating seals or gaskets on rigid components. Other advantages include:
Improved part strength and structure.
Enhanced product durability and comfort.
Faster production and generally lower costs
Overmolding and two-shot injection molding share many of the same advantages. They’re both both simple and effective processes for creating durable parts made of two or more materials or two and more colors, but overmolding is best suited for low-volume production runs and also easier to make.
