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@JayKay PE if there's not enough players for a game this week, you and I could play rock, paper, scissors.  Best of 3?
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Yeah, but plastics don't have a well defined modulus like metal do. Suppliers will publish a modulus, but if you plot the stress-strain curves, they are nonlinear from the start. Also with plastics, the "same" material can be very different from different suppliers. 304 stainless steel is going to be pretty much the same no matter who you buy it from. This is very not-true for plastics. Then some plastics have variations in properties depending on how it's processed (mold temperature, mold pressure, amount of shearing as it's forced through the gate, additives/colorants, etc). And nylons are notorious for absorbing moisture. They will suck water right out of the humidity in the air, and change both dimensions and properties. 

Because of all this stuff we obtain all of our material properties via in-house testing. I'm plotting a bunch of comparison curves now.

Sorry, this is probably way more than you wanted to know.
Anyone hungry? I made spaghetti

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