“There’s nothing wrong with SAE sizes. The problem is when they’re mixed up on the same car.”
Very True for the reasons OK noted.
I have both a Ford and a Chevy that have metric and SAE fittings. This can be interesting when getting tools out to work on them but at least I have both types.
As far as “SAE/Metric equivalents” go, I learned the value of the 14mm–9/16" one doing small engine work.
14mm is (just barely) smaller than 9/16". Most mower blades are held on by 9/16" bolts that are on very tight (and thus easily rounded). I was taught to use a 14mm wrench as a “close tolerance” 9/16" whenever I had to apply a lot of torque. (Occasionally you have to tap the wrench on/off, but I’ve always had it fit.)
And, as said before, the US is not presently “non-metric.” I buy wine and whiskey by 750ml “fifths,” buy soda by the 2L, yet buy my beer by the fl. oz. Vehicular parts are almost wholly metric, excepting Harleys and airplanes. (Although Harleys do list displacement by liter.)
Nor are all other countries totally metric: Britain still uses miles, (imperial) gallons, and weighs stuff (I think only humans+animals, though) by “stones.”
Not everything has been decimalized in the rest of the world. Time for example is almost universally measured in hours, minutes, and seconds. Angular measurements are in degrees although the mathmaticians sometimes prefer radians because it is dimensionless and you really simplify things if you don’t try to find the derivative or antiderivative of a function that includes dimensions.
If you really want to simplify things, temperature really should be measured on an absolute scale, which the celsius scale is not.
“Time for example is almost universally measured in hours, minutes, and seconds.”
Well, during my time as a letter carrier, USPS time clocks measured time in hours and “hundreths.” Dunno how common this is, but it seems unlikely time clocks were built exclusively for postal desires!
“Angular measurements are in degrees”
Apparently because 360 degrees was based on the (then estimated) 360 days in a year. The earth circled the sun, one degree per day.
Let’s not confuse the decimal system with the metric system (or SI system). Human beings have a natural tendency to take a certain measure and divide it in halves, quarters, eighths, sixteenths, etc. Those fractions made natural sense.
The decimal system makes calculating easier, and even the Chinese abacus is based on the decimal system.
The Metric Sytem was Napoleon’s gift to the world, as was driving on the right hand side of the road. It made a great deal of sense in a world where all sorts of incompatible measures were used. In clothing, for instance the length of measure was the “ell”, a length of 69 centimeters. I think it was the averge length of a man’s arm.
During the Russian Revolution in 1917, one of the few sensible things the Communists did was to adopt the Metric System to replace a motly collection of incompatible measures. Unfortunately, they kept the wide gauge rail, refusing to go to the standard gauge in Europe.
One humorous thing happened to me when I worked for a gas utility and had to measure various pipelines along the streets. A surveyor’s tape is 100 feet long and the last foot is divided into tenths, since inches are not used.
One oldtimer watching me got up from his bench and asked me: Heh junior, is that one of them there tapes with 10 inches to the foot?"
I agree that we will have 7 day weeks, 52 week years, etc. for a very long time since they are based on the the planetary movements. Degrees of longitude and latitude seem not to need decimalization either.
If we did change the length of a second to accomodate a deimal based day, it would totally mess up every unit that is derived from the second. Newtons, joules, watts, speed units like mph and kph, volts, amps, farads, henrys, and probably more would all have to be changed to accomodate the new decimal second.
I don’t think we’ll ever do it.
First I want to point out that many of the things we take as being “English measurements” aren’t!
Take 16" tires - they’re actually 15.969" (unless they are motorcycle rims, then the diameter is 15.978") Those values are actually specified worldwide in metric units, but the “name” is an English unit.
I’ve also encountered unusual measuring increments - like hundredths of an inch, instead of fractions.
The real problem for the US? (as being the only major country not using the metric system) - Exporting. Many customers don’t want to deal with non-metric tooling. This wasn’t a problem when the US produced the best equipment in the world and we could dictate what the customer was going to get, but those days are long gone (everyone else caught up with our quality and surpassed us in price!)
I hope no one in business is naive enough to think that they can compete only in the US market and survive. Whether we like it or not, it’s a global economy - and not using the metric system puts us at a competitive disadvantage.
Good point CapriRacer. In the post-WWII era the US amounted to nearly half of the World’s industrial output, and US trade was only 5% of Gross National Product (GNP). Today, US output is about 25% of world production and international trade is now a much larger share of US GNP. NAFTA members, Mexico and Canada are both metric, and other countries having free trade agreements with the US are all metric as well.
In other words, the rules of the game have changed, and Britain and most other ex-British colonies shifting to metric (Nigeria, Canada, Australia, New Zealand, Malaysia, etc.) leaves the US as the lone holdout among industrialized countries. Rapidly developing countries (China, Brazil, India, Russia, etc.) are all metric.
When Malaysia gained independence from Britain, it (like many other colonies) went metric, although they still drive on the left and use British words such as tyre, boot (trunk) windscreen, facia (dashboard), wings (fenders), etc. Malaysia’s economy has the incredible statistic of exports being 105% of GDP. In other words, the exports are 5% bigger than the entire domestic consumption of the country. A very strong reason for going metric.
As stated, those industries that are export-intensive should convert to metric. Another reason for metric is in the miliatry. NATO specifications for armaments and other military hardware are mostly metric, and US defence contractors will have to follow suit.
@ Docnick “As stated, those industries that are export-intensive should convert to metric. Another reason for metric is in the miliatry. NATO specifications for armaments and other military hardware are mostly metric, and US defence contractors will have to follow suit.”
Yes, but they didn’t throw away all their perfectly good .308 caliber rifles, they just renamed it the 7.62 Nato.
That would be like renaming the 1/4 X 20 bolt the “6.35 X 1.27” and saying “were now metric”.
Even the drug dealers went metric! You always hear of kilos or grams of illegal drugs.
If the USA stuck with the push in the 70s to convert to the metric system, we’d be in a far better place now. It was and still is very short sighted to stick with a system that nobody else uses.
The 8 track tape was big in the US, but not in Europe. Should we have stuck with that too?
B.L.E.
Existing military hardware stays the way it is; newly developed NATO hardware is in metric.
There is “hard” conversion and “soft” conversion.
In Canada milk and motor oil is sold in liters, but many other fluids still come in 3.8 liter containers, which is exactly one US gallon. The investment in packaging equipment is such that when the old is worn out, the new will be in hard metric, i.e. liters and 4 liter containers.
Most countries went through a “soft first” then “hard” conversion process.
Fun with non-metric measures:
The diameter of the sun in miles, is almost exactly ten times the number of seconds in a day.
Speed of light in feet per second? Pretty much a billion.
Speed of the earth’s rotation? About a thousand miles an hour at the equator.
None of these things comes out quite as simple in metric units.
the same mountainbike
How much metric drywall, lumber or fencing do you want? You can have it in a few days. I live 60 miles from Canada they have switched over to metric, for almost everything a while ago. Drywall is 120cm or 140cm wide; you buy your fencing by the meter, 2 x 4’s are 40mm x 90mm. There are a lot of houses that don’t use metric , and you can still buy 2X4s although the 40mm x 90mm is so close to a 2x4’s that there is no real need too. You can get other non-metric supplies, but they are becoming a specially item, or you go to the US and buy them.
Docnick
"Yes, nearly the whole world has gone metric. The Three holdouts are Yemen, Myanmar(formerly Burma), and …the USA.”
This statement is not correct with respect to the U.S., and probably not correct with the other two countries either. The U.S. adopted the metric system in 1866. What the U.S. didn’t do was to restrict or prohibit the use of traditional units. The U.S. has not made the crucial transition from “soft metric” to “hard metric”, so that “1 pint (473 mL)” becomes “500 mL (1.057 pint)”, with the traditional equivalent fading into smaller type sizes and finally disappearing.
Even in EU where they are pushing hard to make metric standard “The European parliament on Tuesday 16 Dec 2008 saved the pint and mile from EU extinction, saving British and Irish drinkers from having to order half litres or drive at under 110 kilometers per hour. “
Non-metric units, allowed by UK law for economic, public health, public safety or administrative use from 1 January 2000, are: the mile, the pint and the troy ounce.
Other exceptions, common to many other countries, included aviation, shipping and rail transport – for example, the foot for aircraft altitude, nautical miles and knots.
So even where there is a huge push to metric, there are exceptions.
Basically we have metric to allow easier trade with other countries; we and they don’t have to convert from one system to another. Other than that there is no real advantage from one system to another, if I want more accuracy from the US system I use the decimalize inch, which more accurate then metric and is currently in use.
I believe that it was Pratt and Whitney, pioneers in precision measuring, that standardized the inch as 25.4 mm during the Civil War. Before then, there were as many different yards as there were yardstick makers.
The Mendenhall Order of 1893 made 25.4 mm the legal standard for the inch.
Mountainbike:
I realize that the US made the Metric System legal long ago but the government made little effort to force conversion, such as happened in France under Napoleon and to Russia after the Revolution.
I was raised in a country with metric, then converted to non-metric, and learned to work in both systems. Nearly all ex-British colonies went metric after independence, some more and quicker than others.
Holland went metric under Napoleon, but as late as the 1940s cloth was still sold by the ell (69cm) rather than the meter. Stuff sold in large bags were sold by the “mud”. about equal to 70 kilos.
Because the kilo and the liter are rather large, milk is often bought by the 1/2 liter, a "maat’, and candy and cheese is sold by the “metric ounce”, which is 100 grams.
Goin “hard metric” is a matter of money, and when the old packaging machinery is worn out the industry can then convert to hard metric. I worked for a Swedish company in the dairy processing equipment industry, and making packaging machinery suitable for the US was always a problem.
@B.L.E.
“I believe that it was Pratt and Whitney, pioneers in precision measuring, that standardized the inch as 25.4 mm during the Civil War.”
1879-William Rogers and George Bond begin development work on a machine that later would establish the ‘standard for the inch’. They worked for Pratt & Whitney
1893-The “inch” is legally defined as a fraction of the International Meter of the metric system.
From the Pratt & Whitney site. Actually well after the civil war. But good info none the less, I never realized that P&W had such a stake in precision measuring equipment, I always thought they were just aircraft powerplants.
From the mind of Patrick McDonnell:
Since when do we need to bend over to the specifications of NATO? We’re the most powerful nation in the world. And we pay most of NATO’s bills for them. I resent any implication that we must comply with NATO’s armaments “requirements”.