There are three basic ways to produce plastic parts. Not all of these ways are cost-effective, and not all are suitable for all types of parts and components. The key issue in producing custom plastic parts is to choose the production method with the best match to the desired properties of the end product.
Extruded Parts
Extrusion is a process where melted plastic is forced through a die under specific pressure. It is similar to forcing toothpaste out a tube, but the resulting form of the plastic can be highly complex and not just a ribbon or a solid shape.
Extrusion to produce custom plastic parts is ideal for large volume production of various shapes. There are some limitations to the process as the wall sizes, and the structure has to be appropriate to allow for uniform hardening of the shape to avoid distortion.
Molded Parts
Another common option for the manufacturing of custom plastic parts is through molding. This can include several types of processes, but it includes introducing a liquid polymer into a specific shape and allowing it to harden. This is a very fast process, and the molds can be used for hundreds of thousands of cycles, making it cost effective.
The benefit to molding is the ability to use different colors of plastic and to create non-uniform or non-symmetrical shapes. It is also used to provide highly precise parts with extremely high tolerances.
The other option is to create plastic parts through a machining process. Unlike either molding or extrusion, this uses a plastic form where the material is removed to create the exterior and interior shape. With greater waste and typically longer production times, even with computer-controlled equipment, this is the most costly production method in most cases.
