Designing for 3D Printing and designing for Injection molding is not the same. There are times that you can disregard some of the fundamentals of designing for injection molding, adjust your design at the end and get away with it. But don’t count on this style as a consistent way to succeed or you might just find yourself completely stuck in the end with no way forward.

We speak from experience. The experience of relying too much on 3D Printing technology on a specific project and working with a designer who, while brilliant at free-thinking design and CAD, did not come from an injection molding background. Result, stunning prototypes…and that was the end of it. If you want to mass produce a plastic part or product then you will likely need injection molding to hit your price point for the market. So, be brilliant, be creative, think out of the box, but also stay grounded with a few fundamentals that are required for Injection Mold design, in short, Design For Manufacturability.

  1. Your part needs a draft, so even if you are designing 3D Printed parts without drafts, start trying some designs with drafts to see if your design holds up for injection molding. You need at least a 0.5-degree draft (taper) on all vertical faces. If your design can handle a larger draft, even better.
  2. Heavily textured services or very complex surface finishes may require a 5-degree draft or more. If you are not sure simply submit your design to [email protected] for a tooling quote and our team will do a Design For Manufacturing (DFM) analysis for you with detailed feedback on any problem areas that may need adjusting.
  3. Different plastics have different properties which one should understand before you start designing your part. Wall thickness and cross sections are particularly vulnerable to warping and cosmetic defects depending on your chosen plastic material and your wall thickness. When at all possible, to try to keep wall thicknesses close to each other across your design.
  4. Every smooth surface with an injection molded part requires a lot of extra work on tooling. This means increased lead-times and costs. Before you make everything super shiny and smooth, think, does this surface need to be that smooth?
  5. Sharp corners for injection molding can be a real problem and create stress areas and structural weakness in your part. While each design is different a quick rule of thumb would be to allow for a 0,25 in (6mm) radii in the corners and be prepared to adjust based on feedback from your injection molding tooling supplier.

These are some of the biggest areas of concern you have to look out for when designing for injection molding. If you are not used to designing this way, then dive right in and learn these skills before you make a big injection molding design belly flop

About Start Prototyping

Start Prototyping mainly supply our rapid prototyping service and plastic injection manufacturing for many 3D print companies in the world. Start Prototyping has been engaged in rapid prototyping about 10 years, helping too many designers to turn their ideas into reality. Most of the conceptual prototype of the design has been successfully put into the market and has achieved good benefits. Among them, the most representative metal prototype machining, plastic prototype machining, CNC aluminum machining, Low-Volume Manufacturing, processing technology including CNC machining, vacuum casting, rapid tooling, 3D printing and so on. We have the standard quality inspection process, which is completely in line with the customer’s industrial design. It’s a great honor to be a partner with you. Contact Info Contact:James Yuan Company:Start Prototyping Add:LongGang Village, LongXi Town, BoLuo County, HuiZhou City,GuangDong Province, China Tel:+86-13352636504 Email:[email protected] Web: