> Just so I confirm I understand the calculation, may I restate your calculation: > > Ron wrote, "The dimensional change rate is calculated from the same > data as a 0.001" per 1" per MC%" > > Restated as: > > I'll say my hypothetical sample test piece measured the following pre and post oven > drying > > 6" across the grain pre oven drying > 5" across the grain post oven drying > change in dimension, pre (minus) post oven drying =1" > Emc before oven drying 5% > > 1"(dim change after oven drying)/6"(original cross grain dim) =.166" dim change > per 1 inch of pre oven stock > > If it shrinks .166" with an emc change of 5%, shrinkage with an emc change of 1% > is .166/5= .03" per 1% of emc change. > > Jim I I might have said that inside out. My intent was to have the whole gage strip change a total of 0.010" per 1%MC change, so every thousandth of an inch on the gage would be 0.1%MC, to make it easy enough to read that even I could do it as the numbers on the dial corresponded directly to the MC without needing a conversion chart. So if a 6" test strip got 0.06" smaller with a 10% MC drop, it moved 0.001" per MC% per inch, and to get a 0.010" per MC%, I'd need a 10" strip. A 0.066" shrinkage of the test piece would need a 9.1" strip, etc. The longer the test strip, the more accurate the result. Ron N
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