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Minnesota Rubber and Plastics
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Custom Overmolding of Rubber to Substrate Materials Provides Design Benefits

This assembly, designed and molded by Minnesota Rubber and Plastics, has overmolded components for vibration damping and insulation protection
Photo courtesy of Minnesota Rubber and Plastics

MINNEAPOLIS—The custom overmolding of rubber to substrate materials can provide design benefits ranging from impact resistance and vibration damping to soft touch and esthetic appeal. And as product designers become more aware of these possibilities, they are increasingly relying on the custom overmolding of rubber to differentiate and enhance the product experience. According to a release from Minnesota Rubber and Plastics, the range of applicable products has grown to include industrial and consumer products, from medical devices to sporting goods. Substrate materials for overmolding include stainless steel, aluminum, PEEK, and Radel®, to name a few.

In response to the growing demand, Minnesota Rubber and Plastics continues to expand its range of overmolding capabilities. The company, a full-service provider of high-value rubber and plastic molded components and assemblies, offers CAD engineering support and prototype development to address challenges early and cost-effectively in the planning stages of overmolded product development. These offerings validate performance, avoid rework, protect investments, and preserve schedules.

Another area that Minnesota Rubber and Plastics continues to expand is its materials expertise. Having worked with hundreds of standard—and even more custom—elastomer formulations for over 65 years, the company states that it can provide the "just-right" material to accomplish product design goals. For example, manufacturers can benefit by the integration of rigid parts with softer materials in one unit, a materials strategy that opens a whole new spectrum of product design possibilities.

Features that were previously difficult or impossible to incorporate in medical product designs can become a reality through the overmolding of unique silicone formulations, for example. A lubricious surface finish can facilitate insertion of a medical instrument. A slightly tacky surface, in contrast, can improve the grips of surgical instruments for tactile sensitivity and better instrument control. According to Minnesota Rubber and Plastics, many of its custom silicone formulations have superior impact resistance and are autoclavable with no degradation to the sealing surface.

Numerous other design benefits are available through overmolding, the company says. These are said to include mini molding capabilities for miniature components to very large parts; selection from a full range of elastomer material durometers; custom colorization of components; and conductive, insulated, and implantable materials, among others.

Minnesota Rubber and Plastics (www.mnrubber.com) provides design assistance and prototype development, and operates an ISO 13485:2003 certified quality management system. The company's deep experience in custom materials engineering and difficult molding and sealing applications includes rubber-to-plastic conversions, as well as metal-to-plastic conversions.