g an

The Basic Information About Overmolding

By Jerry Gray


There are many applications that require several materials to be combined together to make a single product. One of the processes through which several materials are combined to make a single item is referred to as overmolding. This process involves a substrate material over which overmold material or materials are applied to partially or fully cover it. Once the overmold material has been applied, it forms a single item with the substrate.

Substrates are of a wide variety of materials including metals, plastics, wood, ceramic, and glass. In some cases, substrates are complete products such as electrical connectors, threaded inserts, screws, molded plastic parts, and machined metal parts. The final product is composed of the substrate as the first part and the overmold substance applied on top. The two are chemically bonded and usually mechanically interlocked.

Various types of overmold materials are in existence today. Rubber and plastics have however stood out as the most commonly used overmold materials. During the process, small pellets are made of the overmold substance before addition of additives like foaming agents and colorants. Careful choosing is necessary because of compatibility issues. Metals and plastics always work well together because they form a strong bond with each other.

Rubber and plastics have compatibility issues when the substrate is made of rubber or plastic of some form. As such, it is the responsibility of the manufacturer to provide a list of all the substrates that plastic or rubber they produce is compatible with and the extent to which this happens. Careful study and application of materials on the compatibility list is needed depending on how compatible the overmold is. The choice of an overmold material should ensure that the strongest chemical bond is achieved.

This process has many application in different settings and industries. It is used to made a wide variety of products for different uses. Some basic examples of products made using the process are handgrips, toothbrushes, laptops, cans, tools, casters, and screw drivers. Examples of the various versions of this process are plastic over plastic, rubber over plastic, plastic over metal, and rubber over metal.

During the procedure, part or the entire substrate is put inside an injection molding equipment. The substrate material is then applied with shots of overmold material onto, into, around it. After the shots are applied, time must be allowed for the overmold substance to cool down and solidify in a process called curing. The final product is a single, joined component.Introducing interlocking mechanisms is advised to make the bonding stronger.

This activity is engaged in for several different reasons. The first reason is the enhancement of beauty and appearance. Color monotony is a product can be broken through the introduction of another material of different color. In fact, different materials with different colors can be introduced to achieve a final product with multiple colors. Secondly, areas of softness and flexibility can be introduced into rigid components using this process.

Another important aspect of this process is reduction or elimination of assembly line time. One can avoid spending time and resources on producing various components that will later be rejoined by only making a single substrate and applying overmold materials. Additionally, application of overmold materials also prevent the use of fasteners and adhesives.




About the Author:



No comments:

Post a Comment