Insert Molding

insert molding

Manufacturing processes grow more sophisticated all the time, and applying new and innovative methods reduce time and cost for the end product.

Insert injection molding, also called overmolding, can accomplish these objectives, thanks to its uniquely simple technique and vast number of applications.

To remove some of the mystery about insert molding, MSI provides this explanation of the process, benefits and typical applications.

What Is Insert Molding?

You may be familiar with injection molding, which pushes hot plastic into a specially designed mold to form new components. Insert molding involves the injection of plastic into molds that contain pre-placed inserts or substrates. This produces a single molded plastic piece with the insert components permanently molded into the part.

Overmolded inserts or substrates may consist of different kinds of other plastic parts, metal components, or possibly even fabrics. The insert or substrate applications range from simple items like threaded fasteners to complex items like decorative labels or electronic components.

How Does This Process Work?

As the name implies, inserts or substrates are placed into the injection mold before the mold closes. The component to be overmolded must be located and held in place properly inside the mold before plastic is injected, and that can be done in various ways including mechanical pockets or bosses, magnets, or even static charging.

After the mold closes the plastic is injected into the mold to encapsulate the intended areas of the insert or substrate. The injection mold is designed to prevent plastic from covering any areas that should be exposed after the injection molding process. The end result is a multi-component assembly that is now a single piece.

What Benefits Does This Method Offer?

Producing insert molded assemblies offers many advantages. It’s a flexible and effective way to blend multiple materials and components into one simple piece in a single step.

Additionally, overmolding with unique combinations of metals and plastics can incorporate the strength of metal with the light weight of plastics. As a result, the end product can be made at lower costs without any loss of performance.

Who Uses Insert Injection Molding?

Insert molding is common in a vast number of industries. Its easy to find a lot of applications in Automotive, electronics, industrial, defense, medical and aerospace.

One of the most common applications in these industries are molding around threaded inserts. (See above)

Your Custom Parts Solution

Thanks for reading our brief explanation on insert injection molding. At MSI, we specialize in manufacturing high quality custom plastic parts that always meet our customer expectations. We focus on lean manufacturing and 5S methods to maximize productivity, reduce waste, and continuously improve production efficiency and safety.

We look forward to helping you bring your custom parts to life. To get started, please request a quote through our convenient online form or call us.