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Plastic Injection Molding a Piece with Undercuts

Plastic Injection Molding a Piece with Undercuts

Plastic Injection Molding a Piece with Undercuts

Hello All,
I am a newcomer to Plastic Injection Molding and would really appreciate some advice.
I have a prototype object that will be made from a type of polypropylene. I only need a maximum of 10 units initially to ensure that the product is satisfactory. The issue is that there are many undercuts in the design. Imagine if you will, a variety of different shaped trees growing randomly in a field. This will be the design. The trees and the field will need to be formed as a single object to maintain strength.
I printed a similar design which was aesthetically OK but due to material limitations was not suitable.
Maybe Plastic Injection Molding is not the approach I should be taking?
Thank you in advance

RE: Plastic Injection Molding a Piece with Undercuts

Other than the top right one I don't see any glaring issues with the other 3..
But slight changes to the top right would make it easily moldable..

Spend a little time reading through the basic resources here..


In general, if you can avoid "side actions", "bump-offs",etc... I "attempt" as best I can to do a simple "clam shell" type mold.. The tooling cost,etc... is far cheaper that way..

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