Custom molded plastic components require a high degree of technical expertise to make. But, when they’re made correctly, they offer high production efficiency and excellent precision. Injection molding also can make components with high levels of detail with little to no need for post processing to finish them.
There are several challenges inherent to custom plastic injection molding, many of which are found in the design of the components and the scale of production necessary to produce these plastic components efficiently.
Design Complexities and How to Avoid Them
Many of the initial challenges facing custom molded plastic manufacturing start with the design of the part. One of the first things that a custom injection molder will do is offer a design for manufacturability (DFM) analysis. This analysis examines if manufacturing a certain component is even possible using the method–in this case, injection molding.
Part designs for injection molding have a lot of different factors to consider. The first of course is the basic design requirements–the dimensions and features that the part requires. Certain features should be avoided as much as possible, such as undercuts and sharp edges. Wall thickness of the part also plays an important role. Part walls should be as consistent as possible. If a part has thin walls, the use of ribs can help to support them. Do not make any ribs or intersecting walls the same thickness as the main wall. If intersecting walls are more than 50% of the main wall thickness, you will have a sink mark visible on the outer surface.
Material selection is another important part of injection molding. Different materials will have different properties that affect the molding process. Certain plastics will require the use of a specific type of mold tooling. For instance, some plastics can be very harsh on tooling, and require the use of hardened high-strength steel, while others can be molded with more affordable, softer P20 steel or aluminum tools.
Keeping Production Scale in Mind
Custom molded plastic manufacturing is typically a process used for medium to large scale production. Because of the initial costs of injection molding, especially if custom tooling needs to be made, it’s not always a feasible option for prototyping, one-offs, and short-runs of components.
There are options available however for low volume production and prototyping. Using cheaper mold tooling materials, keeping designs simple, and similar methods can help reduce the costs of small-scale production in injection molding.
Custom Injection Molding Services at World Class Plastics, Inc. (WCPI)
WCPI invites you to celebrate our thirtieth anniversary with us! We are equipped to handle any challenge that our customers bring us, and support orders ranging from prototypes to mass production, as well as emergency and rush orders thanks to our lean manufacturing capabilities. If you’re looking for a supplier of custom molded plastic manufacturing services, then check out our website today!