Heh; just like how standard railroad gauge (4'8" in the US) is derived, indirectly, from the width of two horses' asses on Roman roads. (Like they say, you could look it up)
Well today I boiled close to 15 gallons of water to purify it for my lager brew that fits 30 litres. Now when my missus got me a temp gauge to stick on the vat it was in F not C. Also with my wind generators I have to make the blades turn counter clockwise as the wind in the northern hemisphere blows in the opposite direction to here in OZ. So either way the europeans have gone with metric and Oz did it when I was a kid. I have found over the past when working on gearbox's I had to work with both and lucky for me I did learn both systems. When I had to a full degree on recon on a gearbox and the enginear said I want the measurements to a micron I did ask metric or imperial..... The look I got was was WOW you are an old school bloke but with the young tech heads here better go metric.
Now some some reason my Dad went and changed the leadscrews on that German Wiler toolroom lathe to imperial but the change gears are all metric module gears. I have found that on numerous enignearing equipment so it would baffle the young apprentice today.
I have to say metric is the way to go as it is base 10 but ry and ask a young guy today to learn imperial..........
Cheers Bryan
...... About to go out and measure a path in feet and it sound a bigger length........
Heh; just like how standard railroad gauge (4'8" in the US) is derived, indirectly, from the width of two horses' asses on Roman roads. (Like they say, you could look it up)
Good catch. (I always like Snopes for debunking stuff.) Although they don't really say that this myth is false, only that it's sorta trivial. So, true, but maybe unremarkable.
Yeah, I'm familiar with mil's (I usually hear it as thou) the other common term I hear is tenths, which is always tenths of a mil. Never heard a micron referred to as anything other than a micrometer though. I do see micro inches for surface finish call out, I work at a machine shop.
So far as I know, "micron" refers only to the metric unit of 1X10E-6 meters. A micro-inch is considerably smaller. The Monarch 10EE lathe was made in Ohio. I read a comment once by a machinist who built them that the lead screws were finished to 25 micro-inches per foot of total error. That's precision for a lathe first built in the late 1930's. I am not sure whether he was referring to those older lathes or the jewels produced in the 1960's. In any case, they were good enough to get us to the moon and back.