Certainly, 3D printing allows users to get parts into their hands quickly, without an investment in tooling. Getting a functional, high-quality part, however, well, therein lies the challenge. Factoring in superior surface quality, lower part cost, testable parts for validation, and the ability to bridge to production, injection molding still comes out on top.
3D printing does serve a purpose for many production manufacturing processes. It is a method that allows companies to accomplish product development quickly. At PTI, we definitely use it in our business, especially on the front end. When customers come to us for support on product development, we have 3D printers at our location to be able to support them. It depends upon their product development needs and the stage at which they are in the project. We also use it in our manufacturing environment for fixtures, gauges, and end-of-arm tooling.
3D printing seems to be a logical choice when contemplating a part that is not able to be injection-molded—when the part design is unique or complex, or for combining multiple parts. With injection molding, the upfront investment is certainly higher when taking into account the cost of the tool, but then it becomes a question of volume. If 16 parts are dropping out of a mold every 15 to 20 seconds or so, it is difficult to imagine a comparable 3D printing situation without visualizing a plant full of costly 3D printers to match that type of output.
While much advancement has been achieved in the 3D printing space, there’s still much more work to be accomplished. For example, additive materials still have a long journey ahead before they can be universally approved and validated across industries. On the other hand, an injection molder could run 1,000 different engineered materials in a year to achieve certain properties (e.g., glass fillers or other content). Once the 3D printing world can achieve that level of diversity with its solutions, the 3D process will present as a more equivalent option to medical device manufacturers.
The post–processing stage is another challenge for the 3D printing industry. At PTI, we have several 3D printers of varying brands in our shop, but all produce parts that require a great deal of post-processing to achieve the aesthetics of an injection-molded part.
Moving forward, we will be making investments into additional 3D printers as well as other technologies. We’re looking at additive manufacturing not only on the plastic side as a method with which to support plastic part development, but we’re also exploring the use of additive on the metal side to be able to develop our molds more quickly and effectively. The objective is to shorten the product development cycle for everyone. That is what’s most important to our customers.
In summary, offering the means to assist customers with product development, whether it comes from a printing process or another manufacturing method, is a unique tool to have in your toolbox. There will come a time when 3D printing will take more of the injection molding market away, but I think the injection molding market will continue to grow alongside additive methods. For the time being, the method used depends on where a company is in a product development process, and what the priorities are in terms of material quality, part volume, and financial position.
John Budreau is the director of new business for PTI Engineered Plastics of Macomb, Mich. He has more than 25 years of experience in engineering, manufacturing, product development, and sales. His business development background in injection molding includes numerous major medical device manufacturers, as well as automotive, consumer, defense, and aerospace industries. Budreau holds a BS and MS in Industrial Technology and Management.