Bart B, I'm not confusing anything (I hope). I'm citing figures from back before CUP came into use in talking about pressures. Data in later loading data books, and other writings, talk about CUP. But factory data in the 1950s and 1960s used psi.
I dunno. Way back when, in my metallurgy classes and some other courses, we measured psi via strain gauges.
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