Injection Molding Plastic

production injection molders

The process of injection molding plastic and custom plastic molding includes a basic set of steps to insure quality plastic parts. When choosing a plastic molding company it is important to find one whose focus is on quality, service, professionalism, and education. This will ensure your plastic injection molds are of the highest quality and that you receive durable finished injection molded plastic parts that meet your specifications.

Injection Molding Process

Plastic injection molding involves several important choices.

First, there’s the design of the part itself. The design doesn’t just influence what the finished part looks like and how it functions. It also informs the plastic injection molds and tooling that’s used to manufacture the part, affecting both lead times and refinement cycles.

Types of Materials for Plastic Injection Molding

Material selection is important too and affects the hardness, weight, price, and flexibility of the part among other factors. Strong mechanical parts are often manufactured with nylon, for example, because of its high melting temperature, toughness, and chemical resistance. However, if the part will be routinely exposed to moisture and humidity, Polyoxymethylene (POM) might be a better choice than nylon because its porosity is lower and it absorbs less moisture.

Surface finish is another consideration when injection molding plastic. Improving paint adhesion or grip, for instance, will require a different approach than striving for a smooth finish or producing a highly polished look.

A reputable plastic mold manufacturer can guide you through all the common questions that arise when designing and producing a part, from material and color selection to considerations around assembly, sustainability, and finishing.

Rapid Prototype Injection Molding

plastic molded parts manufacturer

3D printing is a common way of prototyping parts before manufacturing the final product with injection molded plastic. However, different materials are often used in that process, and the quality tends to be lower than prototype injection molding as a result.

Our rapid prototyping process is different because it’s based on the same options you’d have for long-term production projects. You not only have a large selection of plastic materials to choose from but a variety of custom colors as well.

The same process can also be used for low volume production runs, offering a cost-effective alternative to the higher up-front costs associated with standard production yet still delivering quality that’s superior to 3D-printed prototypes.

Design and Engineering

Designing a component for production with injection molded plastic in mind requires considering the whole process from the outset. Fewer parts and simpler geometry can save money later on. When you consider a battery-powered screwdriver, for example, the handle might also serve as the battery compartment and needs to be designed accordingly.

Designing 3D parts requires a lot of experience along with specialized CAD software. We don’t expect every customer to have this knowledge or software much less intimate knowledge of the plastic injection molding process, so our engineers are available to shepherd you through that process.

From even a simple 2D drawing, we can create a 3D model and walk you through the design considerations that affect the cost and quality of your part.

Additionally, we can guide you through material selection and suggest potential improvements with an eye towards minimizing costly changes down the road.

Plating, Pad Printing, and Assembly

After parts are created with injection molded plastic, there’s often still work to do. Multiple parts might need to be assembled to form a larger component, a 2D image might need to be printed onto the part through a process known as “pad printing,” or the part might need to be plated with a substance like chrome or copper to give it the appearance of metal.

We offer all those services as add on options to our injection molded plastic production process, and we also offer special packaging options including layer packing, cell packing, and poly bagging.

Insert Molds

Insert molding has several benefits including:

  • Reducing or eliminating assembly costs
  • Allowing more design flexibility
  • Increasing strength
  • Improving reliability
  • Shortening lead times

Our insert molds have a cavity side and a core side that fit inside of a custom mold base and are a great choice for small and medium sized parts that require low quantity orders or fast delivery.

They cost less to build than our free standing molds, but they’re made to the same quality standards and produce the same kind of high-quality, long-lasting parts.

Free Standing Molds

Free standing molds, or “stand alone” molds, are designed and built to include the base, inserts, and all components they need to be fully functional on their own.

They carry a higher price tag than insert molds but are a better option for parts that won’t fit into insert molds and are a good choice for high-quantity, multi-cavity production. Our free standing molds are designed and built for production inside any properly-sized standard SPI molding machine and generally have 1 to 8 week lead times.

What Are Some Types of Injection Molded Plastic Parts?

  • Sports Equipment: Whether you’re looking to manufacture football helmets, treadmills parts, or archery components, the sporting goods we manufacture from injection molded plastic are tough, impact-resistant, and surface-finished according to your specifications.
  • Electronics: Precision and consistency are of particular importance in the electronics industry because the parts created from injection molding plastic are often used to surround wiring that could be damaged or potentially cause harm.
  • By employing a modern, technologically driven process, the electronics parts we deliver are designed and engineered for safety, precision, and durability.
  • Marine Accessories: Marine accessories such as deck plates, propellers, paddles, covers for electronics, and fishing rod holders need to be durable and highly resistant to corrosion to stand up to the rigors of a marine environment.
  • From UV additives and anti-corrosive agents to considerations around material selection, weight, and functionality, we can guide you through the process of designing and manufacturing marine-grade parts from injection molded plastic that are durable yet cost-efficient.
  • Agriculture: Parts made for the agriculture industry need to be tough, impact-resistant, and stand up against moisture and UV light.
  • Our team takes those considerations into account when designing and manufacturing parts for agricultural machinery, including ensuring the proper additives are used so the parts will stand up to the demands they face in the field.
  • Laboratory Instrumentation: We have the experience and capability to manufacture a variety of laboratory instruments with plastic injection molding.
  • Centrifuges, pH testers, blenders, tensile testers, and viscometers are just a few examples of the kinds of lab equipment we can help you design and manufacture parts for with injection molded plastic.