Tag Archives: gravity

Understanding the Gravity of the Situation

If you work in the injection molding industry long enough, at some point in your career you will be sure to hear someone say “turn the mold 90 degrees (or 180 degrees) to see if the problem changes”. And when asked why on earth would that person suggest such a thing, the answer usually is “because gravity is pulling the plastic down to the bottom of the mold”. At this point everyone gets a good laugh and makes fun of the person who suggested such an absurd solution. But are plastic materials immune to Isaac Newton’s Law of Universal Gravitation? No. Then why is it considered absurd to think that gravity could not influence the filling of a plastic part made by the injection molding process?

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