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Re: Most Powerful FIRST Team created T-Shirt Cannon
I think the real problem is the 'glassy' behaviour of PVC at room temperature. This is a characteristic of the polymer, and means it will fail in a brittle manner (fatigue and brittle fracture, neither of which would be non-catastrophic in a pressure vessel) rather than the ductile failure mode of a tank made of most metals or a different plastic.
I don't get why people choose to build a PVC air cannon after all the warnings that have come out over the years. There has to be a safer way of doing this.
EDIT: fatigue is based on the pretty much uncontrollable microcracks in your material, it could fail after 1 cycle or a million, and it is pretty much impossible to tell when it will fail.
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Last edited by ,4lex S. : 22-05-2010 at 15:48.
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