Lessons learned making a plastic injection mold with a Chinese mold maker #Manufacturing

airgadient shares how they had cases for their air quality monitors manufactured in China via plastic injection molding:

Design your Plastic Part from the Start with Mold Suitability in Mind

From the very start of your design phase, it is highly recommended that you (or your designer) has some knowledge about mold making and can make design choices that make the mold simpler to produce. So for example:

  • If possible avoid undercuts in your design. Undercuts are for example if you need holes on the side of a plastic enclosure. Often you cannot completely avoid undercuts but then you need a slider which is typically not too difficult to do but it adds to the mold costs.
  • Avoid changes in thickness of the plastic as this can often lead to marks on the plastic as the plastic cools down differently
  • Think about the parting line in your design. The mold consists of two parts, cavity and core. Often when the two parts come together, a small line will be visible on the plastic. So it’s important to think in your design where you want to have this line
  • You cannot have 90 degrees in your mold. For the mold to exit your plastic part, it needs to have a slight angle of a few degrees. This is why you will see most plastic parts not have 90 degree angles but slightly wider. Think about how a plastic bucket becomes slightly wider at the top.

See the full list of tips in the post here.


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