Breaking the Mold: 3 Steps to Understanding the Injection Mold Process

From massive and durable car parts to intricate and delicate medical equipment, plastics are powerful material in the manufacturing process. To get the most out of plastics, many manufacturers turn to the efficient plastic injection mold process.

What are plastic injection molds? The process takes a high focus on design to create an efficient and effective product that you can produce over and over again.

The plastic injection mold process is a mainstay in the manufacturing industry but how does the process work? To make the most out of your production, let’s dive into the process to find out.

How to Make a Plastic Injection Mold

The process to make a plastic injection mold comes in 3 intricate steps. The first step is product design, where the product’s details form in relation to the rest of the process. The second step involves crafting the mold for the best output. The final step begins the manufacturing process and puts the product into production.

Each step has many layers and details that are important to consider. Even one misstep can send you right back to the drawing board. Let’s dive into the steps themselves.

Product Design

The first step of the plastic injection mold process is also the most vital. The design process is where you create the core concept of your product. It is also the best place to correct and manage any potential mistakes.

Most product designs these days use a digital setup, often a form of CAD software or similar program. This allows for the easiest manipulation and changes without needing to alter a prototype design. Some designers may still prefer to work with physical models but it is a preference, not an industry standard.

There is a long checklist of items that need consideration during product design. The main 3 are function, aesthetics, and manufacturability.

1. Outlining Your Function

Start the design process with your function. Whatever you need the product to do needs to come through in your function design. It seems simple, but not outlining each aspect of your function can make certain aspects of your product weak.

For example, if your product needs to protect and store a piece of delicate machinery, then your product needs to be durable. That same product should also have a form that fits snug over the machinery. Balancing the perfect fit with the extra size for durability may be difficult.

2. Considering Your Aesthetics

Aesthetics may seem like an inconsequential part of the design process, but they can influence how your product fits together. Softer edges and corners can make for smoother connection points.

Avoiding stress in your design, such as issues that can come from 90-degree corners, can help reduce mold defects. Uniform thickness is also a helpful guide to keep your product sturdy as well as helping with changes later on.

Aesthetics does also work into marketability, which can be key if your product is a new design you want to sell to other manufacturers. Blending your aesthetics with product function and manufacturing fit will help to refine your product beyond the bare minimum.

3. Checking on Your Manufacturability

Your design should do more than create a quality product, it needs to also produce a design that is easy to manufacture. Manufacturability helps to cut down on your molding costs and manufacturing problems.

Reducing the number of pieces you have to manufacture reduces the number of individual molds. You should also note the size and shape of your product, as elaborate pieces can make for extra issues during the molding process.

Your product will also need assembling. You can use design to help ease the process with designated fits and simple pieces.

Injection Mold Design

The next step comes to designing the mold itself. With a product design in mind, the mold making can begin. First, make sure to test your design for assembly difficulties, how it fulfills its function, and whether it has any irregularities. This is often done with a physical model prototype.

Once you have a design that you are happy with, you need to design the mold itself. There are 3 major aspects to consider for this.

1. Understanding the Types of Molds

Molds themselves are often made of metal. The common metals for molds are hardened steel, prehardened steel, aluminum, or beryllium-copper alloy.

Hardened steel is the most expensive but most durable. Prehardened steel is cheaper but wears out faster. Aluminum works best as a limited run mold, as it is fragile but efficient. The beryllium-copper alloy helps with heat removal.

2. Designing the Proper Draft

A draft for the mold is the angle that ejects the product from the mold. Having a poor draft to your mold can slow down or even ruin the production time. Be mindful of this when constructing the mold, especially if the piece for the mold is intricate or large.

3. Placing or Sizing Gates

Gates are the opening in the mold where you insert the plastic. This will also be a scar left by these gates when production is complete.

Make sure to design around this so the scar is not a problem for the final product. A scar on the wrong side can make fitting pieces together more difficult.

The Manufacturing Process

The final part of the process of creating a plastic injection mold is the actual manufacturing process.

1. Understanding the Types of Plastics

There are two types of plastics, either thermoset or thermoplastic material. Each material has its own positives and negatives, as well as what situations they work best for. Either can find use in the plastic injection mold.

2. Detailing the Injection Mold Process

The injection mold process itself has several steps to turn the granular plastic material into your finished product design. We have a more thorough description of the process listed here.

Getting the Most Out of Plastic Injection Molds

With a closer look at the process of creating and manufacturing a plastic injection mold, you can see their potential for efficiency. With an eye on design, plastic injection molds allow you to take a unique and well-crafted design and push it for easy mass production.

Plastic injection molding is the core of our production here at Nova Stevensville. We refine our process day by day to provide the best plastic production on the market. Contact us today for more information!

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