Introduction

A smart manufacturing decision lies in choosing the right process. The two manufacturing processes that have caught major attention today are injection molding and 3D printing. Even though both can produce plastic parts of very high quality, their production goals are so different that they cater to different markets altogether.

An in-depth knowledge of the pros and cons, cost, speed of production, material selection, design freedom, and applications of each of the processes will help you in selecting the most cost efficient solution.

Understanding the Two Manufacturing Processes

What Is Injection Molding?

Injection molding is a process of manufacturing used chiefly for making large numbers of parts that are the same. The first step of the procedure involves melting the plastic granules. Then the hot and flowable mass of plastic is forced with pressure into a precisely crafted mold. Once it has hardened, the mold is opened and the item is pushed out.

The mold fabrication is a one-time expense. The mold can be employed thousands or millions of times. This results in the cost of each item coming down very substantially as the number of goods delivered goes up. This is one of the reasons injection molding is one of the more commonly employed techniques for producing large volumes.

Best suited for: Automotive components, Medical devices, Consumer electronics, Industrial equipment, Household products, Packaging.

What Is 3D Printing?

Sometimes, 3D printing is called additive manufacturing. That means making things by stacking layers of materials one on top of each other. And these layers are made according to a 3D CAD model of the object. This is in stark contrast to injection molding that actually requires a physical mold. That???s why it???s a lot more flexible and lets manufacturers produce parts directly from their designs without needing to make the mold first.

Point is, 3D printing comes with very little preparation time, since it doesn???t require any tooling, so it is the perfect method for producing prototypes, customized products, and low volume manufacturing occasions where repeated change of design is an expected event.

Best suited for: Functional prototypes, Custom products, Product development, Small production batches, Complex geometries.

Cost Comparison

Injection Molding Costs

The most significant cost component of the injection molding process is the mold itself. Based on the design and features of the component, mold costs can be from few thousand dollars to even tens of thousands of dollars. Once the mold is ready, production costs become very minimal for each part in addition to a small amount.

Injection molding is the most cost-effective method for medium- to high-volume production of thousands of the same parts.

Typical Costs:

  • Tooling: High initial investment
  • Production cost per part: Very low