Overmolding

Compared to other injection molding processes, overmolding provides improved functionality, appearance, and bond quality to products while saving you time and creating cost-effective plastic injection molding solutions. Overmolding requires exacting specifications with little room for error. HiTech Plastics and Molds has the knowledge and experience to develop overmolded products for many industries, including:

What is Plastic Overmolding?

A type of injection molding, overmolding is a multistep process where two or more components are molded on top of one another. Due to the multiple steps, it is sometimes called two-shot molding.

Overmolding can involve molding plastic on plastic or plastic on metal to create a high-strength bond between the part and overmolded plastics. As everything happens in a single operation, the need for assembly is eliminated. Common applications include creating two-tone aesthetics, gaskets and seals, or adding grips and buttons to objects.

Does Your Part Require Overmolding or Inserts?

Overmolding and insert molding are both subsets of injection molding. While both processes involve the same injection of plastic into a mold cavity, there are some key differences to understand while deciding if overmolding or insert molding is best for your application. While overmolding takes a part and then layers plastic in an exterior layer, insert molding embeds small parts during the injection molding process.

Choose overmolding when:

  • The completed object is made of thermoplastics or rubber
  • The design calls for multiple layers, materials, or colors
  • You are manufacturing both the substrate and secondary layer
  • The finished object does not need to be disassembled

Consider insert molding when:

  • Your substrate is prefabricated
  • Your substrate is made of metal, wires, or computerized parts
  • The finished part is one solid and complete piece

Of course, exceptions apply to every rule. If you have more questions, the experts at HiTech Plastics and Molds can help you find the injection molding process, design, and product to meet your specifications.

Overmolding Materials

Overmolding is a highly adaptable process. As a result, a large variety of materials can be used in the overmolding process. At HiTech Plastics and Molds, we utilize overmolding using:

Can You Overmold the same material?

Yes, you can overmold the same material. This is especially useful when using thermoplastics to form the interior and exterior layers in overmolding and insert molding.

Overmolding Plastic on Metal

When overmolding plastic on metal, the durable plastic is molded over the metal component. Overmolding plastic on metal is often used in manufacturing plastic handles on metal tools and in the medical, aerospace, and consumer goods industries.

Overmolding Plastic on Plastic

When overmolding plastic on plastic, the more rigid plastic component is first molded, and then the more durable plastic material is molded over the previous plastic part. This process is often used to create handheld devices, soft grips for consumer products, and a wide range of medical devices.

Get Started on Your Overmolding Project with HiTech Plastics and Molds

Since we started in 1984, HiTech Plastics and Molds have offered our customers engineering excellence paired with years of valuable experience. We provide US-based manufacturing and overmolding solutions for any industry or application. In addition to our overmolding services, we provide other secondary services including:

If you’re ready to learn more about our overmolding and other secondary services, request a quote or contact us today. We provide high-quality, cost-effective solutions to your plastic injection molding or mold building applications.