Why Choose Injection Molding Over 3D Printing?

When you need custom plastics manufactured, there are three options for production when using thermoplastics: thermoforming, injection molding, and 3D printing. Typically, heavy-gauge thermoforming is ideal for large pieces and plastic components that don’t require complicated details. However, if you need small plastic parts or products or pieces that have complex details, your best options may be either 3D printing or injection molding. But which one is better for manufacturing? To help you decide, we’re going to break down which one is a better method of production for your plastics.

How Does Injection Molding Work?

Injection molding involves melting down thermoplastic pellets to a liquid, and using a high-pressure injector, forcing that plastic into a double-sided custom mold made from a steel, aluminum alloy, or a copper alloy. As the plastic is cooled, it’s ejected from the mold and then functional and aesthetic customization is added.

How Does 3D Printing Work?

A 3D print, also called additive manufacturing begins with a three-dimensional computer model which is then digitally sliced into hundreds or thousands of thin, horizontal layers. When it’s ready to print, the horizontal layers print one at a time, one layer on top of another building the object from bottom to top.

Comparing Injection Molding and 3D Printing in Manufacturing

To determine which one of these methods is right for your order, let’s look at three main factors - cost, lead time, and accuracy.

Costs of Plastic Manufacturing

Injection molding has a higher up-front cost than other methods of plastic manufacturing because the tooling and mold costs are high. However, once that mold is made, it can be used for as long as you need, even for fulfillment orders decades in the future, meaning you can easily scale production and lower your costs.

Additive manufacturing, on the other hand, has the same price per unit no matter if you need one piece, 500 pieces, or 250,000 pieces, and costs for ink, materials, and energy to run the printers can become cost-prohibitive quickly.

Production Time

While the tooling can be time-consuming to design and develop, once it has been approved and is ready for use, production for large volumes of plastic components and products moves quickly. Similarly, fulfillment of future orders offers a short turn-around time because the tooling is readily available.

On the other hand, 3D printing offers a quick turnaround time for individual pieces, but because pieces are printed one at a time, there’s really no effective way to speed production. While injection molding plastics take longer up front, sometimes up to 16 weeks from design to delivery, once the prototype is approved, all adjustments have been made to the design, and the tooling is ready, the turnaround time ramps up quickly.

Accuracy and Quality

Just as important as cost and time is quality. After all, you need your plastic parts and components to be durable, long-lasting, and consistent from one piece to the next as well as accurate to the original design. Because injection molding relies on rapid prototyping to see how the piece works as the design comes to life, there’s ample opportunity to edit the model and ensure it offers exactly what you need. Once it’s as close to perfect as possible, the tooling is designed around that prototype so that every piece that’s manufactured matches the prototype.

With additive manufacturing, you can also enjoy highly accurate, consistent plastics, and because the CAD drawings can be edited easily, adjusting the design is simple.

Choosing Injection Molding or 3D Printing

Both methods have value in the world of plastics manufacturing. In fact, 3D printing allows us to quickly create prototypes that allow us to bring the model to life, let you inspect and approve it, and then determine if any edits are necessary. Having the ability to print out a model in a short period of time relative to creating tooling cuts down on the lead time and improves our quality and accuracy.

However, once the prototype is approved and production begins, injection molding is a cost-effective, efficient way to get the products you need. So, while both are highly important to the process, when it comes to mass production, injection molding is the better option.

Contact Our Injection Molding Company Today

At Advanced Plastiform, Inc. our experienced team will work with you through design, prototyping, and manufacturing your custom plastics to ensure you get the accurate, high-quality products you need at a low cost per unit price and a short turn around time. Our Zebulon, North Carolina headquarters gives us a central location to deliver to seven states, including North Carolina, South Carolina, Pennsylvania, Maryland, Tennessee, Georgia, and Virginia.