Today's KNOWLEDGE Share:Reducing curvature radius

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Today's KNOWLEDGE Share:

Have you ever really understood why curved parts have a systematic tendency to warp as depicted here, reducing the curvature radius ?


The nature of "mold constraints" in molding leads to a "thickness shrinkage" systematically higher than the in-plane part shrinkage. This classical problem is well known in the composite molding world, and referred to as "spring forward" deformation. In the case of fiber filled materials the lack of fibers in the Z direction is the driving mechanism.

The moment you mold a part with any curvature, the law of Physics will create this type of deflection. When parts have a "corner" shape, this is called "corner effect", and has very little to do with cooling problems, contrary to common belief.

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