In a lot of the world, nowadays the only place where you encounter miles, elbows or feet are fantasy settings (because using old measurements helps with the “fantasy” bit) and historical ones such as the Bible. Some old units stay around, but they’re normally understood to be for “rough measurements”: handspans are “about 20cm”, not “exactly 20cm” (they used to be “exactly 20cm” if you were buying a home in Barcelona due to the high prices, but the advent of the internet has brought that market into line with everybody else). The expression “to measure something by the handspan” reflects how inaccurate human-body-based measurements are.
I know how tall someone meter-sixty is: about my height (a bit shorter, if exactly 160, but we tend to round to 0-5 so we could be the exact same height). I know how tall someone five-four is: about my height. But for some reason, a lot of Americans and of translations to American English leave there absurd figures: I was recently reading a book which had been translated from German into American English, where someone was described as “going to work when she had a 104 degree fever” (that’s 40ºC in the rest of the world, but when was the last time someone who’s native in Farenheit used that too-exact figure? You’d say 105, or “a high fever”!); every roughly-estimated temperature which would have been a 0 or 5 number in the original was left as a weird number nobody would give when estimating in Farenheit. So, from my point of view, part of the problem with conversions is trying to put into the converted value more precision than the original had.
YMMV, but my experience is that fevers are reported exactly, down to the tenth of a degree even. We even think our correct normal temperature is 98.6 degrees exactly, even though it’s really a range of about 2 degrees.
The fever of the person in question had not been measured, though, it’s an expression, not a description of an actual medical case; the temperature comes up in the context of someone saying that she’s so dedicated to her manager and so convinced that the office can’t run without her that she’ll go to work when a normal person would stay in bed under a pile of duvets. I realize that many Americans find it normal to go to work when you’re sick as a dog, but I can’t remember a single person complaining about “my coworker came to work with a fever of 104”… what, did you measure your coworker’s fever?
As others has mentioned, most of worlds population uses metric and considers imperial and US measurements “unnatural”. I wonder how much resistance there were in other countries when they were “metrified”. Take this Chronology of conversion by country.
France by 1795 needed a single national standard, revolution or not, they could have tried to agree on one precise value for pound and feet, but chose a completely new revolutionary (sorry) system. There was a lot of scientists influential with the revolutionary leadership, they would be advocating units with easy conversion and definitions. The industrial revolution was in its infancy, there were less precision tools and machinery around which needed to be scrapped or recalibrated. To apeace tradionalists it was enough to introduce the metric pound (=500g, still in use) and the metric foot (1/3 m, not so much).
Once France converts all its smaller neighbouring trading partners will have to convert sooner or later. Even exhausted by war and political turmoil France was a technological and economical powerhouse. Trade and import of technical know-how is so much easier with common measurements. So Netherlands, Belgium and the western german states switch to metric. After german unification the rest of the country converts, and the german industrial juggernaut starts to take off. Now all Germanys trading partners will have to switch.
Great Britain was the only country ahead of France in trade and tech at the time, but they waited until 1824 to officially standardize measurements. I wonder if imperial units could have been the worldwide standard (shudder) if they had been quicker on the uptake in that regard. I’m pretty sure the Royal Navy had standardized internally long before 1824.
Nicolás Fernández de Moratín, “Saber sin estudiar” (to be learned without studying):
Admiróse un portugués
de ver que en su tierna infancia
todos los niños en Francia
supiesen hablar francés.
«Arte diabólica es»,
dijo, torciendo el mostacho,
«que para hablar en gabacho
un fidalgo en Portugal
llega a viejo y lo habla mal;
y aquí lo parla un muchacho».
A Portuguese was stunned
that from their earliest days
all children in France
French spoke.
“The Devil’s arts must this be,”
he pouted,
“that this French babble,
a Portuguese gentleman
speaks it badly in his old age
and here any lad can speak it!”
Not disagreeing Loch Raven, but the shop I’m working at now has mostly ancient machinery. Some of it’s War Production Board, made in the '40s. We do a lot of stuff for local ranchers/wineries/farmers and they mangle John Deere stuff and Kubota stuff. JD’s inch, Kubota’s metric, so we cover it all. We make use of digital calipers for a lot of our measuring needs, hence the “one button” comment about conversion. On the other hand, all my mics are inch but if I throw a 2" mic on a part and see 1.181" or so come up I know from experience I’m looking at 30 mm. Or if I mic .984 (25 mm) I’ll grab the 63/64" collet knowing it’ll fit. You’ve also probably gotten used to some of the more common stuff, i.e. using an 8 mm wrench for 5/16", 19 mm for 3/4 and so on. My point is that when you work with both systems on a day to day basis the conversion is less obvious and painful than being “forced” to go one way or another. Most folks don’t have our advantage of dealing with both systems and one is more “foreign” than the other. Gearheads and tinkerers just get used to the differences and similarities easier. If the U.S. ever does convert to metric, I think the old stuff will just slowly go away. We don’t do much in Whitworth threads, but once in a while one comes in and out come the 55 degree threading tools. Still got 'em stashed away.
Fellow old fart and probably no less fond of change for change’s sake…
I don’t mind it, most stores here use both pounds and kilo’s. 2.2 lbs to a kilo. I hate Celsius…it doesn’t seem as precise as Fahrenheit. So all our thermometers in our home are set in farenheit.
I find this to be downright silly, household thermometers just aren’t accurate enough for that. That 0.1°C precision is plenty when you got a ±2°C error in the measurement.
Yeah, I understand where you’re coming from, and yeah, we do use the tool that fits rather than buying (or going and getting) the “correct” one, so I do agree with you on that. And most of our metric prints have huge tolerances and on those you could probably do OK with a WalMart tape measure. But we also do some seriously picayune stuff with nominals of, let’s say, 1.315 +0, -.0003. For that, there’s no way you can get away without a really good mic (i.e., “touch that Mitutoyo and I’ll shove your Shars up your ass!”). The digitals I’ve seen will only give you .0005–although that may have changed as it’s been a while since I’ve seen a new one.
I’m curious though about what you said about the machines you use. If your stuff is War Production, it’d have to be cam machines, am I right? Or hand machines like those monster old Warner & Swaseys that everyone seems to have tucked in a corner of their shop just in case a nuclear blast knocks everything else out of alignment? Because there, in an analog format, you have the potential for infinite adjustments, whereas with CNCs, you’re limited to .0001. So in some ways your machines are actually better suited to switching between systems.
We have a couple wheezy old Hitachis and some newer Moris, plus a brand-new Okuma, and to my knowledge only the Okuma might have the capability to switch between standard and metric. I’d have to check, though, and that would require me to remember to do that until Monday, and that’s a lot to keep in the overloaded, low-capacity buffer of my brain. But if I do remember to check, I’ll post about the results.
Out of curiosity, what properties are measured in in^4? I hadn’t realized that there were any quantities of interest with units of [length]^4, outside of relativity and theoretical math.
Loch Raven,
All of our stuff is manual, except for one bed type CNC 2 1/2 axis mill. The WPB machines are a gallant old LeBlond lathe and a shaper (remember those?). The shaper is a once in a while deal, used mostly for internal keyways too long for broaches. No cam type automatics like Brown & Sharpes or Warner & Swayses, though I did work with them some when I was young and dinosaurs roamed the earth. Mostly, we do work that is in good old +/-.005" tolerance range, excepting press fits and the like. No grinders other than a tool post grinder. I ran a mold making shop for a plastic company for 15 years and did have to hold “tenths” there.
I think guys like us that grew up mostly without digital stuff and CNC’s had, and have, an advantage. We bridge the gap between inch and metric easier than most. In my case, I started messing with “furrin” cars in my teens and they were metric. One just gets used to using mixed measurements working with a variety of stuff.
Nice shootin’ the breeze w/you about shop life, but we’re probably hijacking this thread some, huh? Too bad Fred Dibnah’s gone, he’d have some colorful things to add when it comes to “the old ways”.
I worked in the auto industry, we converted in the late 70’s. Every B/P I’ve seen since 1980 has been in metric. As far as machine tools go, all the scales used by cnc machines are in metric. I was the “gage guy”, I programmed CMM’s and other gages. Of course, the auto industry uses the same designs in multiple markets, so metric is the only way to go.
Fahrenheit temperature ranges are straightforward enough. Above 100 tends to be hazardous; above 85 is just plain hot; 65-75 is livingroom temperature; 45-55 is a bit chilly; below 45 is cold; 20 is unpleasantly cold; and around 5~0°F is where your snot starts to crystallize. I think that is a very practical value. At -5°C, exposed mucus membranes tend to be a non-issue, I find the F reference point far more useful.
(Adjustments for humidity and wind throw any scale off.)
It is odd how long the metric system has been in coming to the U.S. I’ve got a book on railroad car design and construction that’s a reprint of the late 1800’s original. In it, the author lays out the advantages of the metric system and confidently states that it will only be a few short years until the whole industry converts to it’s use. I suppose the U.S. has had the “advantage” of being the big dog on the block economically and being somewhat insulated as a result. As you point out though, much of what goes on “behind the scenes” has quietly converted to metrics. Like some of the former British Empire, we still cling to our old system for the every day non critical stuff like our weight, height and temperature. I do think conversion is inevitable (resistance is futile, you will be assimilated) but like the header on this website says, “It’s taking longer than we thought”. Then again, we don’t all speak Esperanto. Humans can be stubborn.