Forming polypropylene?

[Tofflemire]

Hi All

I would like to know if it is possible to heat and form a polypropylene part. I have a half sphere and would like to have a flat surface on it. Can I apply heat to soften the material and form a flat surface? The thickness of the material is approximately 5/32". Do I have to be concerned with property changes? I.E. spidering, cracking and weakening of the material?


Tofflemire

 

[aspearin1]

Polypropylene is one of those wonderful materials known as a thermoplastic. You can heat it, melt it, and resolidify it without changing its chemical properties. You should be able to take a flat piece of metal, heat with with a blow torch and press it down on that ball to get the effect you're looking for. Polypropylene has a fairly low melting temperature, and it's not advisable to heat the whole part. You'll likely get deformation.

aspearin1

 

[patprimmer]

PP is a high shrinkage material, and while it can easily be thermoformed as described correctly above, it is prone to differential shrinkage and therefore warpage, so you will get a flatish surface, but truely flat will prove difficult if not impossible. It really depends on just how flat you want.

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pat

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