Plastic Custom Molding Processes

by | Jul 18, 2016 | Injection Molding

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Plastics are compounds synthetically produced in labs. As a material, the4y have proven to be quite versatile. Molding it into various different forms then hardening the material, creates a vast array of products we commonly use. In today’s manufacturing world, plastic is extensively used. From decorative material to practical items, plastic custom molding processes produce everything from automotive parts to utensils for your kitchen.

Plastic Molding Processes

Whether the company is producing a custom component or running off a batch of standard items, the methods can differ depending upon the intent, the equipment and the cost. Among the most common processes manufacturers employ to produce plastic items – customized or otherwise are the following:

  • Injection Molding: This very versatile form of molding is common for the production of the mass production of automobile parts, bottle caps, cell phone stands, kitchen utensils, surgical components and toys. It uses small or large machinery to force melted plastic of various types into the cavity of a usually steel mold to form the required part. Upon cooling, the mold is removed using pins. Today, this method is particularly popular in spite of the initial set-up cost. While it may be expensive for an initial custom molding of a part, later the process makes each unit economical in a mass produced run.
  • Blow Molding: Instead of into a mold, the melted plastic resin flows into a parison – usually a molten tube. The process is similar to glass blowing. It is used for producing various forms of hollow items such as containers including one-piece bottles and tubes in large groups economically
  • Compression Molding: As the name suggests, this process involves compression or pressing. Instead of molten or melted plastic, this requires a slug of hard plastic. It is pressed – usually employing vertical rather than horizontal presses – between two mold halves previously heated. After air-cooling, the manufacturer now has automobile components. Popular materials include fiberglass, reinforced plastics and thermosetting resins.
  • Extrusion Molding: This form of extrusion molding puts the melted plastic directly into a die avoiding the use of a mold altogether. The plastic takes the shape of the die. This tubing is then cooled. A manufacturer may request the entire roll or ask for it to be cut prior to shipping. It is no surprise that extrusion molding is suitable for such items as pipes, straws and tubing.
  • Rotational Molding: This process uses molds attached to a rotational device. The equipment moves into a closed furnace room for melting before swinging it slowly back into cooling room. This type of process provided hollow plastic parts suitable for large containers

Plastic Custom Molding

Each method of molding has its purpose. By talking to experienced and expert engineers and designers, you can discover what process is suitable. They can help you understand the different processes and direct you to what method best suits your plastic custom molding design project.

Molded Devices Inc. (MDI) opened up shop in 1963. Since then, they have expanded their operations while never giving up on their reputation to produce quality items. For Custom Molding of all types, including dip and injection, they are leaders in their field. They will work with you and your company to move your product from conception through prototyping right through to completion. You can always count on their engineers and technical staff to provide you with a solution that is optimal for your company and its budget. To discover more about the company, and what it offers, visit them online at

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