Is it too late to remind people that the main advantage of Metric over English, that is decimal increments, is available in English. every time this subject has come up on this list, I've told people to go look in their favorite machinist catalog for steel rules of 16R gradations (32ds and 16ths on one side, and 10ths and 100ths t'other). 0.010" is equivalent to .25mm. Until my mid-40s I could still read them by eye, but they're still there with glasses and strong sunlight.
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