Is it really “metric”?
Most of the so called 3/4” plywood that gets delivered to my shop actually measures out closer to 11/16” in thickness. That’s because, I am told, that it is “imported” plywood and is measured, not in inches, but in millimeters.
A sheet of plywood contains 32 sq. ft. of wood (at least I think it’s wood). At three quarters of an inch in thickness, that’s the equivalent of 24 board feet of material. But at 11/16, if you take that “missing” 1/16 and cut it into one foot squares, you will have a stack 2” high (1/16 x 32) which translates into two board feet of wood per sheet, each of which now actually only represents 22 board feet of material. If you multiply that over a unit of 40 sheets of plywood, there is a total of 80 sq. ft. of plywood “missing” or the equivalent of right around two and a half sheets.
Draw your own conclusions…
The other day I went into the “mongo-mart” that got built right across the highway from my shop. I wanted to get some drinking water for my cooler. There were “gallon” bottles on the shelf and without really looking I grabbed three of them. When I went to pour them into the cooler, I noticed that each “gallon” bottle had a large indentation on the bottom that removed at least a pint from the volume of the bottle. So my three gallons was actually only about two and three-quarters gallons. Is it just me or is there a similarity here?
Again, draw your own conclusions…