Whether you want to create a prototype or a high-volume production run, injection molding offers an affordable solution. To decide on your next project wisely, learn more about the typical misunderstandings regarding this manufacturing technique. Injection molding can be used for various materials, including food and medical-grade resins. The molding process is also environmentally friendly.
It’s Cost-Prohibitive
Injection molding is a very cost-effective manufacturing process. It’s not only more economical than 3D printing or CNC machining, but it also has the added benefit of being able to produce multiple identical parts at once. Although injection molding does generate some scrap, this is primarily from the injection gate locations, sprue, and runners. Thankfully, much of this scrap can be reused in future production runs. With revolutionary biopolymers on the horizon, eliminating plastic waste is possible. There are still a lot of expenses related to injection moldings, such as design, maintenance, utility, and raw material prices. However, minimizing secondary processes and ensuring your part’s design is optimized for manufacturability from the start can significantly reduce these costs.
It’s Not Versatile
Injection molding has a reputation for not being as versatile as 3D printing or CNC machining, but this is not true. The versatility of injection molding allows it to work with various substances and hues in various settings. Plastic injection molded parts must be painted or finished after production because the injection process doesn’t change the product’s color. Plastic injection mold makers can also utilize a variety of additives to increase the strength, durability, or aesthetic appeal of the products they produce. Many believe plastic injection molding produces low-quality production pieces, but this is untrue. The reality is that plastic molds can produce thousands of high-quality products before they run out of their lifespan, just as long as they’re well-maintained. It offers significantly more than what can be produced using a CNC-machined mold or an aluminum prototype mold, which can only generate a limited number of pieces before changing.
It’s Not Environmentally Friendly
Plastic injection molding is a green manufacturing technique constantly evolving to be more environmentally friendly. Although heating polymers and injecting them into molds still needs a significant amount of energy, manufacturers are making great efforts to increase the effectiveness of their equipment and reduce waste by emphasizing process optimization. The type of polymer and mold used will also play a role in how much environmental impact the process has. Many eco-friendly plastic injection molding companies use thermoplastics instead of thermosets because they can be remolded without compromising their chemical makeup. These plastics can also be recycled and reused, which helps to reduce ground pollution, greenhouse gas emissions, and waste production for landfills. Injection molding does produce scrap in the form of runners, sprues, and anything that leaks out of the mold cavities, but this material is not sent to landfills and can often be recycled for future projects. Manufacturers are also looking into electric options for their legacy machinery, which would significantly reduce the amount of electricity used in their facilities.
It’s Not Aesthetically Pleasing
Injection molding is often portrayed as a resource-intensive method unsuitable for prototyping. This process can produce prototypes faster than other methods, and the results more closely resemble the final product. Unlike other molding techniques, injection molding can create parts in virtually any quantity – from prototypes of a few pieces up to seven-figure production runs. Although creating a steel mold requires a sizable initial expense, it’s crucial to remember that the quickness with which components may be produced makes these expenditures worthwhile over time.
Weld lines are a common concern for many customers, but this can be prevented by making sure that the part is given enough time to cool and that there is uniform wall thickness in the injection mold design. Additionally, incorporating draft angles into a molding design can help prevent warping defects from occurring. Over-molding (or two-shot) to combine plastic with other materials, such as metal, adds strength and a more attractive look to a finished product.