Just when I thought I managed to contain my metric arrogance…

Huh, the explain link says the dimensional sizes originated from the wood being cut at the listed size while green, then shrinking as it dried. I was told that it was done for construction purposes, where the wood would likely be covered by plywood or drywall that would bring the dimension up to size. I never questioned it before; that always seemed plausible enough.

And that’s what men the world over use to measure their appendage!

I feel this was the true decline of America.

Interestingly enough, this concept was used in pattern making for casting machine parts back before modern machining and parts manufacturing.

They were colloquially called shrunk rulers, and looked like a standard ruler, but was actually longer to account for the shrinkage of the material being cast.

For example, say you’re casting a part from iron, which shrinks 1% as it cools, which amounts to 1/8 inch per foot.

An iron shrink rule would look standard, but actually measure a foot as 1 foot 1/8 inches to account for the shrinkage (this is an example and not meant to be actually accurate).

Source: am historian that interviewed pattern makers that used shrink rulers in their work.

Can still work as long as you use the same ruler and just use referenced measurements.

That will go nicely with a tape measure that uses the Chinese inch (cùn), which is equal to 1.312 imperial inches

This hurts so bad to think about

Eh, not a problem at all. You can’t make it look exactly like my other three and I make sure to use the same tape measure throughout a project, really after the first couple cuts I’m not even using it I’m using the cut pieces to measure against.

I don’t care what the number actually is, just that I can mark in the same spot consistently.