When it comes to manufacturing, you have a lot of options, especially as modern technology continues to change the manufacturing industry in new ways. Two very similar, but very different, methods are injection molding and 3D printing.
Both injection molding and 3D printing are additive manufacturing methods. Unlike machining methods, additive manufacturing does not carve away material to create a product, but instead adds material on, forming the product from the ground up. In many ways, this allows more customization options and also works to conserve material, reducing unusable excess and thus reducing waste.
However, injection molding are different in very serious ways. They work through different methods. Their capabilities and limitations are very different. What are these important differences? How should that affect your choice of manufacturing method?
Injection molding has been around for a very long time, first being used in 1878 to create plastic products. It works by injecting molten material into a mold. Injection molding is now used not only for plastic but for a wide variety of materials including glass, metals, and confections.
Injection molding is done by feeding material into a heated barrel, then fed or– as you may guess– injected into the mold. The material is then allowed to cool inside the mold, resulting in the desired shape
The core element of injection molding is the mold. These are often made from metal (typically steel or aluminum) using precision machining methods. Molds can be reused extensively, though they are the source of most expenses in injection molding.
Precision is what makes injection molding work as a manufacturing method. Not only must the mold be very precisely designed and machined, but manufacturers need to carefully consider the material being used, the material of the mold, and the properties of the injection molding machine being used. However, once these interactions are understood and accounted for, injection molding can be used to mass produce products quickly with very high accuracy.
3D printing is a simpler process than injection molding in some ways. It works by utilizing a specialized 3D printer to build a product layer by layer based upon a computer file. 3D printing is relatively new and was first used in the 1980s, usually in research labs. It has since graduated to commercial use.
Many materials can be used with 3D printers, including many different plastics and several metals. Ceramic 3D printers are in development and will be available soon. There are even a few places where food can be 3D printed.
3D printing is capable of a very high level of detail. It can be used to make shapes that are often otherwise impossible as there is no need for support structures or molds that need to be machined. Quality will vary based upon how fine the layers are as well as what kind of post-treatment is used (some materials require it).
3D printing is generally quite fast, especially when you have designed a product from scratch via a CAD file. There are limits to 3D printing, however, as the size of the printer determines the size of the product.
Injection Moulding vs. 3D Printing Costs
The costs of 3D printing and injection molding are heavily influenced by the methods by which they work.
Injection molding has a high startup cost. The mold itself has to be made first, for once, which requires precise tooling and verification. This makes it quite expensive for the production of only a few units, though the cost per part starts to go down significantly when units are mass produced.
3D printing costs the same for every unit, whether you order a handful or hundreds. The process simply requires less setup. The cost per unit stays fairly steady even with mass production, as you are largely paying for the cost of material at any one point.
3D printing is constantly improving and gaining a foothold in industrial manufacturing. The flexibility and creativity made possible by 3D printing have allowed for products to be made that simply couldn’t be made before, from customized prosthetics to ultra-light drone parts.
At Jawstec, we incorporate the latest 3D printing developments to help you leverage this fast-growing technology to improve your business or project. We offer top-tier 3D printing design services that can help move your product from idea to reality. Contact us today to get a quote for your 3D printing project.