The 2 shot molding process (also known as dual injection, double injection, multi-shot injection and overmolding) involves combining multiple levels of your product into one mold. When done correctly it produces a high quality, strong and durable final product. It eliminates secondary assembly steps, which is a cost saving and production time saver. This makes it a popular choice for products that require both load-bearing structural components and cosmetic details like soft, grippy surfaces or different colors.

The basic concept of 2 shot molding is that a first injection of one material is made into the initial mold, once it’s hardened the injection unit then rotates and injects the second material into a cavity that has already been formed. As the screw moves back and forth the material mixes, melts and forms a new bond with the existing material in the original mold. It’s important that manufacturers consider the chemistry of the materials to ensure that they are compatible with each other to form a strong molecular bond. Incompatibilities can cause weak spots in the finished product. In order to ensure the two parts are bonded together, undercuts and shoulders may be included in the design of the initial mold to lock them together.

A key advantage of 2 shot molding is that multiple layers of your product can be molded into the same product without the need for joining or welding. This significantly reduces manufacturing time and costs and improves the overall quality of your finished product.

It allows designers to incorporate complex mold designs that can include functionality that would be impossible with other methods of manufacture. For example, a toothbrush handle can be molded with both a rigid base plastic and softer rubbery surfaces that are more suitable for the human hand.

In addition, using the 2 shot injection molding process can eliminate the need for welding or glue which are prone to weakness and damage. It is also more environmentally friendly and easier to recycle.

As a result of these benefits, Dymotek uses the two-shot injection molding process to produce many of its medical devices and industrial components. Our experts are well versed in the nuances of the two-shot injection molding process and can guide you to the best solution for your specific project. Contact us today to get started! We will walk you through the process and provide you with a quote. We look forward to hearing from you..