14 Dec Designing Parts for Injection Molding
Injection molding is as much an art as a science. There are so many factors that can make or break your part, sometimes literally, and you may not have control over all of them. Many of the variables rest in the tool design, such as whether to add cooling lines, whether to use hot runners, or where the gate is positioned, while others result from the process parameters, such as cycle times or temperature profiles. However, as designers, it certainly helps to make the most of those variables that we can influence, primarily the design of the part itself.
- Uniform wall thickness
- Radii on the corners
- Sufficient draft
- Bosses
- Ribs
- Choice of parting lines
- And many more
Learning how to design a perfect injection molded part can take a long time and could require years of learning lessons the hard way. There are many books on the subject, but sometimes a great resource is the downstream vendors themselves. I’ve said it before, and I’ll say it again, it never hurts to work closely and early with vendors when designing custom parts. They’ll be designing the tooling and controlling the process parameters, so they can help you understand what works best.
ProtoMold is a rapid injection molder – they turn soft-tools and injection molded parts around quickly. To help designers make the most out of their services, they’ve provided a Design for Moldability reference with a few of the most fundamental concepts discussed. While their capabilities are slightly limited to provide such quick turn-around, their guidelines provide several sound ways to improve an injection molded part, resulting in less expensive tooling and a better performing component. (Registration required to view the document)
Disclaimer: Key Tech is not connected in any way with ProtoLabs or their affiliates and was not compensated in any way for pointing out this guide to you. We just like their work.
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