If you’re any business that relies on plastic parts on a regular basis, these parts being reliable and consistent is very important. These are themes that are huge within the plastic injection molding world, and there are several variables that go into creating plastic parts that are robust, durable and reliably consistent.

At EnviroTech Custom Injection Molders, we’re proud to offer a variety of custom injection molding services, from bulk molding to slab stock molding and numerous other areas. We observe a carefully-cultivated process for the creation and repetition of any of our plastic parts across numerous industries, ensuring all our clients obtain only the very best plastic materials. What are the important components that play a role in the creation of an ideal plastic part, and how can you be sure you’ll be getting each of these from a quality plastic injection molding partner? Here’s a primer.

Mold Design

First and foremost is the actual design of the mold in question, which is vital for any injection molding process. It’s important not only for the efficiency of the process, but also for the ability to create a high volume of parts with consistency.

And while the term “mold design” seems simple enough, this area is actually incredibly varied and detailed depending on the precise needs of the client. Firstly, we’ll work with you to determine some basic needs for the part: Its function and application, plus how it will relate to other parts, as well as factors like dimension and ability to withstand elements, pressures or chemical combinations.

Once we have these answers, our engineering team will get to work on designing your mold. We’ll look at numerous elements as we move forward here, including the wall thickness required, rib and boss design, weld line, corner transition, and any gate or vent placement that’s required for the mold. On top of this, we go the extra mile and conduct a DFM analysis, short for Design for Manufacturability – this is a test to ensure your product meets the highest possible quality standards. Only once all of these steps are carried out can the building and testing of the new mold be done.

Tool Design and Features

In many injection molding processes, the single element that takes the most time and commitment is the design of the plastic injection molding tool itself. Building the tool takes time and accuracy, but also requires extreme precision to create the perfect plastic part.

Firstly, it’s important to work with injection molding professionals who use high-quality materials for their mold bases. Stainless steel is the preferred material here, as it’s both high-quality and very durable. We also focus on precision within our toolmaking, plus strict and resolute quality standards and tolerances. Here are a few of the tool design features we often highlight to clients:

  • Core metal: As we noted, this is primarily stainless steel, which withstands the pressure of a production run while meeting all tolerances and quality standards.
  • Mold base: Mold base cost and design themes will largely be based on size and the type of steel used.
  • Cavity number: When possible, we try to optimize the number of mold cavities to increase production capability.
  • Cavity machining: Customizable molds are often based on cavity, core, ejector, cooling line and other element placement.
  • Complexity: Part complexity refers to areas like surface finish, number of needed undercuts and other final factors that help us arrive at the final cost of your mold – plus ensure it will last for years.

Resin Choice

Next up, it’s time to select the right resin material for the plastic part that will be created. This is one area where our current options are exponentially greater than what was available to those in our position even a generation ago – this is due to improvements in polymer science that’s made many more resins available, plus has led to the creation of several higher-quality resins.

Just like the tool design process, resin selection depends largely on the specific needs of the client and their required part(s). We’ll ask you about things like your part’s desired appearance and distinct areas like texture, color or whether you want them transparent; we’ll also look at factors like strength, flexibility, rigidity, chemical resistance, regulatory requirements, and even the life expectancy of the part based on the resin being used. All of these elements will play a role in the final decision for your plastic resin, at which point we’ll reach out through our extensive network of resin suppliers and find you the very best material.

Production Methods, Practices and Care

Finally, once we’ve manufactured the mold and have worked with you to choose the ideal resin for your plastic part, it’s time to move forward with production. Facilities like ours will be home to a variety of different plastic presses and related items, with different performance capabilities and options depending on the mold size, the resin you selected, the number of cavities and other factors.

During any first run of a new plastic part, we will first do a sample run to check for defects. If any are found, we correct them and do another test. Once no defects are present, production is allowed to move forward – though it’s supplemented by regular quality checks throughout the process. This involves inspection with high-quality equipment, but is required to ensure there are no issues anywhere along the line.

For more on the components that must be addressed to achieve a custom plastic injection molded product, or to learn about any of our plastic injection molding services, speak to the staff at EnviroTech Custom Injection Molders today.