3D printing may be new technology, but it is definitely here to stay. It has already disrupted the traditional manufacturing industry and will do so even more in the future. As 3D printing becomes cheaper and more accessible, expect its impact to reach every corner of manufacturing.
As 3D printing technology improves, more and more people are beginning to wonder if it will eventually replace injection molding as the go-to method of manufacturing plastic products on a large scale.
In this article, we’ll look at the similarities and differences between the two methods and figure out where they might overlap in the future.
What is injection molding?
A mold is created using computer-assisted design (CAD) software. This is a process called Computer Numerical Control (CNC). The mold, then, is used to create identical parts over and over again, which are then filled with molten plastic that solidifies as it cools. This creates an injection molded part.
It’s likely you’ve come into contact with thousands of injection molded parts in your life; common items include everything from toys to automotive components. Since its invention by John Wesley Hyatt in 1868, injection molding has become incredibly efficient at creating large quantities of identical parts quickly and cheaply.
Why would anyone want to replace it? Well…there’s one big drawback to injection molding: high production costs make making small batches cost-prohibitive. By contrast, smaller print runs of custom parts can be produced through selective laser sintering or fused deposition modeling technology for just pennies on the dollar compared to injection molding prices.
What are the benefits of injection molded parts?
It’s easy to forget about injection molded parts when you see headlines about 3D printed gadgets and futuristic materials, but it shouldn’t be forgotten. I think there are several reasons why injection molded parts are still around, and why they won’t disappear anytime soon.
Let’s take a look at a few of them
- Speed – For many applications, injection molding is simply faster than other manufacturing processes. The time between an idea and prototype can often be measured in days or weeks instead of months or years
- Complexity – While 3D printing can allow for complex geometries with tiny features that make injection molding nearly impossible, injection molds themselves have gotten quite complex in recent years as well (fused deposition modeling has opened up some exciting possibilities here).
- Cost – When volume isn’t important, 3D printing might save money on tooling costs (or even raw material costs), but for many products injection molded parts cost less per unit.
- Material selection – This one is key: Injection molding allows manufacturers to select from thousands of plastic grades suited to their particular application. There aren’t any truly universal plastics; each one performs differently based on factors like hardness and temperature resistance
- Accuracy – Achieving high-resolution details and smooth surfaces using 3D printing is difficult, whereas injection molded parts are incredibly accurate
- Sustainability – Injection molded plastics generally offer better recyclability than many 3D-printed materials
- Convenience – Finally, injection molding requires little more than heat and pressure; no post-processing is necessary. If mass production of a part is required and speed is an issue, then injection molding will almost always provide better results
5 Frequently Asked Questions About 3D Printing & Injection Molding!
1. How much does 3D printing replace injection molding?
Well, it depends on your definition of replacing. Personally speaking, my definition means that there should be nothing stopping injection molded parts from being used just as commonly (if not more so) than their 3D printed counterparts.
Right now injection molded parts dominate certain industries where 3D printing hasn’t yet made significant progress. That’s partial because 3D printers haven’t been able to match injection molding speeds and tolerances, but I don’t think it will stay that way forever.
2. Who uses injection molded parts?
Manufacturers across all industries use injection molded parts. Their durability makes them ideal for heavy equipment, appliances, automotive components, and office furniture.
3. Where do injection molded parts go after use?
Much of our plastic waste ends up in landfills around the world, which is bad news for our environment. Plastics are non-biodegradable, meaning they never break down. Injection molded parts are long-lasting, but they’re also recyclable. You may be surprised to lean that the recycling process is actually quite energy-efficient – much more so than producing virgin plastic.
4. How might 3D printing disrupt the manufacturing industry?
There’s no question that consumer adoption of 3D printing has skyrocketed in recent years, but as far as disruption goes, you might be surprised to learn that it hasn’t yet made much of a dent. While certain types of industries (like product design and aerospace) are already experiencing disruption from additive manufacturing, other industries—including injection molding—seem to be thriving, even with widespread access to affordable 3D printers.
What gives? Let’s take a look at some key differences between injection molding and 3D printing, along with some arguments for which process is better for plastic manufacturing project.
Here’s what we found: In many instances, each approach can yield comparable results; however, injection molding generally offers greater speed and accuracy than 3D printing does. Both processes also carry different costs and benefits when it comes to working with large-scale orders.
It seems that two main factors—accuracy and speed—are leading players in determining whether or not injection molding will replace 3D printing anytime soon.
5. Who will be impacted by a disruption in this area?
For at least a few more years, plastics producers are in a comfortable place. Yes, 3D printing is improving and innovating at an alarming rate, but it’s going to take time for 3D printers to replicate anything close to what injection molding can do. Even if that somehow does happen, manufacturers have plenty of time to adjust and react.
As long as companies stay ahead of their competitors on these fronts, there’s no reason for them to panic just yet. It may be inevitable that some manufacturing processes will eventually be disrupted by newer technology, but injection molding isn’t going anywhere any time soon.