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Metric System

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Here in the UK we hear that the USA is deeply embedded in the imperial system and simply will not accept the metric system. I can't help wondering how accurate this perception actually is? I've certainly read articles by American authors who have used metric measurements and it does seem easier to see which is biggest of, say, 8mm or 7.5mm whereas comparing 5/16 in with 19/64 in requires a little more grey matter. So where do American woodturners stand on this issue? Personally I'm not above using both and sometimes mixing them if it's convenient. Is it really the big deal over there that we are told it is over here?

Bob
 
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Is it really the big deal over there that we are told it is over here?

Bob

No. Except to groups who think Dr. Strangelove and the Flintstones were documentaries, and who will stand and fight to "preserve the purity and essence of our precious natural fluids" from all invaders, whether ferin or de-metric!!!
 
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john lucas

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Some of the really oldtimers still think that way. Myself and many of my machinist friends are very comfortable using both. I think that changed a lot when cars started being manufactured all over the world. Used to be if it was american made it had our measuring system bolts. If it was foriegn made it had metric. As a photographer mixing chemistry I became comfortable with both out of necessity simply because the instructions came one way or the other and you had to adapt. I still use both in woodworking. For example it's very easy to divide 7/16 in half, it's 7/32. It's harder to divide lets say 27mm in half. On the other hand if I measure a board and it's 300mm it's easy to divide that in half. If I have a board that is 11 7/32 that takes some thinking to divide in half. So I use both and try to have scales and rulers that easily adapt to both.
I still don't totally understand metric machine thread sizes. It's easy for me to understand 1/4" at 20 TPI. Not so sure about 6mm x1m Gotta read more on that I guess. I just pull them out and use them or grab the metric tap or die if needed.
 

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I use both.
When I give a measurement it is in inches
When I have to do arithmetic on a measurement I use metric.

A few of us are old enough to remember that the US adopted the metric system in the late 80s or or early 90s.
Once all the gas pumps were converted to liters and the oil companies set higher prices we repealed the metric system
and the oil companies changed all the pumps back to gallons and raising prices yet again.
 
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The metric system isn't much of controversy here since it is not used in many public applications -- food is weighed in pounds/ounces, liquids measured in pint/quart/gallon, lengths in imperial. Given the degree of globalization, many aspects of life in the US are metric (such as imports from almost anywhere), but that is concealed. Any proposal to move entirely to the metric system raises howls, so it is unlikely to be carried through. Meanwhile, it is actually everywhere. Most packaged food uses both systems. Large bottles of Coke actually are 2 L.

My life involves both. Daily life in the US is imperial. But my career as a Near Eastern archaeologist over 40 years has been exclusively metric -- I think of the pottery I handle, and dimensions of trenches etc, purely in metric. In the workshop I use either -- certainly metric is easier for splitting measurements.
 
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A few of us are old enough to remember that the US adopted the metric system in the late 80s or or early 90s.
Once all the gas pumps were converted to liters and the oil companies set higher prices we repealed the metric system
and the oil companies changed all the pumps back to gallons and raising prices yet again.

Hmmm, not as I recall. This jibes with what I remember:
Congress passed the Metric Conversion Act of 1975 "to coordinate and plan the increasing use of the metric system in the United States." A process of voluntary conversion was begun, and the U.S. Metric Board was established. But the efforts of the Metric Board were largely ignored by the American public, and, in 1981, the Board reported to Congress that it lacked the clear Congressional mandate necessary to bring about national conversion. In 1982 the Board was dissolved.

http://www.ebsinstitute.com/OtherActivities/EBS.qs2df2.html

Being a voluntary conversion, it has yet to be embraced; but then again, it’s only been 40 years. My elementary students measure geometry with both scales. I believe we are becoming somewhat comfortable with metric linear measure and a sorta on the way if you’re talking liters, but very resistant when it comes to temperature.

I think it should have been a cold-turkey mandatory conversion. That would have saved millions or maybe billions in conversion errors over the decades - not the least of which was the Mars Orbiter failure.
 
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kids today cannot add, subtract, divide, multiply without some type of devise....I need pencil and paper

metric vs lbs, fluids, etc no way

how much tea went into boston harbor????????????

I tend to ignor the metric system if anyway possible.....I do not do any precise work, do not have to, so I don't

I have great respect for people who use the power of 10......cannot imagine doing anything without 10....100....1000....etc

never had to drive on the left either

both good system.....sort of here do it this way, over their do it their way ....sort of king of the hill
 

john lucas

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Well I never have understood using Hands to measure a horse. :) I'm going back to Cubits, especially if it keeps raining as much as it has lately.
 

Bill Boehme

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It hasn't been "metric" for over a half century

The SI units of measure are an internationally agreed upon set of standards. People refer to it as the metric system, but it isn't really. The trouble with "metric" was that there were numerous metric systems that didn't precisely agree. The same problem plagued the English or Imperial set of measurements. The SI system of measurements replaced the definitions of all of them. Many people who say they will never go metric don't realize that they actually already have to a certain extent because Imperial units are now precisely defined in terms of SI units. For example, the inch is now precisely 2.54 centimeters. Once upon a time, it depended on which country's yard and what other country's meter you were talking about and how good were the measuring tools and how many decimal places you were willing to go.

...... That would have saved millions or maybe billions in conversion errors over the decades - not the least of which was the Mars Orbiter failure.

All US Government agencies and contractors have been 100% converted to SI well before I began my engineering career. Electrical engineers have been metric and SI since the turn of the century ... that would be the previous turn of the century not the recent one. I don't know which specific failure you may be referring to, but stuff fails. NASA projects are designed to be fault tolerant, but stuff happens. Sometimes it is human error. I don't knowq if you are old enough to remember when we were able to successfully soft land a probe on the moon. After a thorough check out to verify that all systems were GO, it was turned off to save battery power. The problem was that EVERYTHING was turned off including the receiver that got the commands to turn back on.

kids today cannot add, subtract, divide, multiply without some type of devise....I need pencil and paper......

So, pencil and paper are your "devise"?
 
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measurements

My 'Merican machinery is put together with fasteners that God and Louis Chevrolet meant for us to use. The furrin stuff is metric. My Norton was Whitworth. My rifle cleaning rod is an old British military thread, of which there were many different ones. The only machinery that annoys me is the stuff that bounces around using both metric and fractional inch bolts. For a few years our cars were like that, never knew what a bolt size was going to be. Inch or metric, my eyeballs were pretty well calibrated, mix the two and they didn't work as well.

Cheap tool sets don't matter much, their wrenches are often the exact same sizes in some nominal sizes. Handy to know that 14mm in a decent tool set is a very tight 9/16 when the 9/16 bolt head is damaged. 13mm and half inch are generally the same tool. 8mm is an inch crossover too I believe, used to know the ones that crossed over all the way up to an inch or a bit bigger but I haven't worked daily with wrenches since the eighties. I used to crossover drill sizes between metric, fractional, letter, and decimal drill bits when I was in a machine shop daily too, now I have to hunt a chart or more likely grab a digital caliper, a wonderful toy that makes the difference between metric and fractional sizes pretty much meaningless.

There are a lot of times when I would settle for one system, I don't care which one!

Hu
 
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our us $$$$ bases on 10, everything else is lbs, feet, etc

british $$$$$$ not based on 10 (correct me if I am wrong), everything else is based on 10....metric

strange
 
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When I was preparing to head over to Phoenix to demonstrate at the AAW Symposium, I was very aware of our perception here in the UK that the Americans don't do metric, so I made sure I knew all of my measurements in both 'languages'. I was surprised to find that most of the guys out there at the Symposium seemed perfectly able to operate in mm!

The funniest thing about all this is that, with the average age of the audience at a woodtuniing demo being 60+ (at a guess) if you start talking in mm at a demo in the UK you are just as likely to draw blank looks. As a demonstrator it is pretty handy to be able to work in both!

When I was at school we were taught in cm, when I left school it quickly became apparent that the only people that actully use cm are schools teacher! Presumably so they only have to tech up to the 10x table. When I left school to work for my Dad, the first thing I had to do was learn my 12x table, so I could work in feet and inches! Now days, all drawings come through in mm.

Cheers

Richard

PS: The Pound (£) is divided into 10s these days (100 pennies being a pound). I think we dropped the old system in the 70s? but it was before my time so someone else would be able to confirm this.

PPS:I never have been able to get my head around farenheit, celcius makes far more sense to me - 0 water freezes, 100 it boils. We all know where we stand!
 
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PPS:I never have been able to get my head around farenheit, celcius makes far more sense to me - 0 water freezes, 100 it boils. We all know where we stand!

understandable....I grew up with 32 degrees freezing

we have hurricans, watch the barometer for weather changes, (I have in the past lived in florida)
England has always been a seafaring nation, not so much hurricanes, but seafarers
 
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I grew up with metric. Used them for scientific purposes where it is the standard, and for my woodworking hobby. It works fine. But...when I started to use the imperial I went crazy: fractions, impossible fractions etc but...fractions are good. 12 divided by 3 is four divided by 4 is 3 by 2 is 6 etc. this is the enormous practical and simple advantage of the imperial 12 inches foot. At least in woodworking. Furthermore, everybody can visualize a 1/16 but one millimiter is more difficult, it is too small similar to 1/32 and perhaps useless in many woodworking applications. A pencil mark is about one millimiter so...
In conclusion, while I think that metric is more accurate and more scientific, imperial is more practical in many non critical situations. Having both systems at the same time must have rounded more nuts than a nutcracker though.
 
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All US Government agencies and contractors have been 100% converted to SI well before I began my engineering career. Electrical engineers have been metric and SI since the turn of the century ... that would be the previous turn of the century not the recent one. I don't know which specific failure you may be referring to, but stuff fails. NASA projects are designed to be fault tolerant, but stuff happens. Sometimes it is human error.

Apparently not quite 100% as of the late 1990s:
"The 'root cause' of the loss of the spacecraft was the failed translation of English units into metric units in a segment of ground-based, navigation-related mission software, as NASA has previously announced," said Arthur Stephenson, chairman of the Mars Climate Orbiter Mission Failure Investigation Board.
http://mars.jpl.nasa.gov/msp98/news/mco991110.html
 

Bill Boehme

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Apparently not quite 100% as of the late 1990s:

http://mars.jpl.nasa.gov/msp98/news/mco991110.html

I speak fluent NASA, so allow me to translate: The root cause had everything to do with mismanagement and poor communications and nothing at all to do metrology (the science of measurement). However, ground based computer modeling of the mission used English to metric conversions so it is the convenient scapegoat.

The fact that that programming errors existed is not the problem. They always do. Part of the design process is performing V&V testing (validation and verification). The fact that it wasn't done was a management failure of the worst kind. Everything could have been 100% metric or any other units of measure and the same problems would have existed and would not have been discovered.
 
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its common for written software not completely done by one person, but bits and pieces to be done by many persons, if no v&v, I am surprised they found the water cooler
 

Bill Boehme

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Finding the water cooler was the backup plan. :rolleyes:

A brief explanation of V&V testing:

Verification is the process of showing that the software does what you intended for it to do.

Validation is the process of showing that your intentions were correct.
 
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Thanks guys, it’s been interesting and informative reading your varied responses. It seems that there is the same sort of variation in the US as here. Richard was spot on with his comment about the older members of the British woodturning (or any other) fraternity resisting metric (or SI as Bill correctly comments) units.

I agree with John that it’s easier to divide 7/16 in half than 27mm, but now try dividing them by three instead. He’s right though that it makes sense to choose whichever units are most convenient. Rules here often have inches (subdivide usually into eighths, sixteenths and sometimes thirty-seconds) on one edge and centimetres, subdivided into millimetres on the other edge. If something happens to be exactly three inches wide (say) then that’s what I’d use, not 76.2mm.

For the record Britain changed to a decimal currency in 1972 From 240 pennies to the pound we moved to 100 ‘new pennies’ (imaginative name, or what) to the pound. By now the ‘new’ has been dropped and they are just simple pennies again. Surprisingly there was enormous resistance to the new system - again mostly from the elderly (I wasn’t in 1972, but might fall into that category now). We also had a currency unit called a guinea which was one pound and one shilling (1 shilling = 12 old pennies = 1/20 of a pound). Oddly its still sometimes used but now is one pound and five new pence (I/20 of a pound). Incredibly people worried that decimal currency might be too complicated!

As an ex-schoolteacher I have to disagree with the sentiment behind Charlie’s comment about kids today (‘kids today cannot add, subtract, divide, multiply without some type of devise....I need pencil and paper’). I doubt that American kids are so very different from British kids, and I think he’s mistaken to cast doubts on their abilities. Sure, they might reach for a calculator - and why not - that’s what calculators were invented for. If they didn’t have one I’ve no doubt they’d figure it out. On the whole the majority of teenagers today are just as well educated as most people now in their sixties, but with different knowledge and skills.

(I can get into a rant about putting down young people. Over here I frequently see signs in shops saying ‘no more than two schoolchildren allowed in at a time’. The implication is that if you can’t watch them they are going to steal everything in sight that’s not bolted down. As a group I refuse to accept that schoolkids are any more inherently dishonest than any other identifiable group of people - there are villains at all ages. I’m waiting to see a sign that says ‘no more than two pensioners (or woodturners, or gardeners, or…) allowed at a time.’ Rant over…phew…deep breaths…calm…calm…Sorry Charlie!)

It’s been an interesting read. Thanks

Bob :)
 

Bill Boehme

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.... Over here I frequently see signs in shops saying ‘no more than two schoolchildren allowed in at a time’.

Are there any limitations on school dropouts?

BTW, we have the same kind of rulers -- inches on one side and cm/mm on the other -- the thing that I am curious about is the length of the ruler used on your side of the pond. Ours are one foot long which shows at least a subtle, if not overt, preference and maybe even a subtle form of brainwashing. :rolleyes:
 
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That's a good question Bill! It's revealing that I knew without looking that my rules go to 12 inches, but I had to look to check the metric side. I knew it was around 30 centimetres but wasn't sure of the exact markings. It stopped at 30 centimetres. Interestingly (to me, anyway) I have a metric only rule that also goes up to 30 centimetres - in other words it's still a foot long! My two-foot rule obviously goes to 24 inches, but on the other edge it reaches 60.5cm - an odd place to stop.

I also have a seven inch rule, although it's something of a curiosity since most small rules are six inches long. The first three inches are graduated in 32nds, the fourth inch goes to 64ths and thereafter its graduated in 16ths. The first 10cm on the metric edge are graduated in half-millimetres, the rest in mm. It goes up to 17.7cm. The extra length proves extraordinarily useful.

My woodturning rarely requires any accurate measuring at all. If pieces have to fit together I make them fit but by trial and error, not by cutting to a predetermined measurement. When I do measure, its always in mm unless some imperial measurement just happens to fit the bill.

Bob
 

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I am a machinist with a company producing medical instruments. The medical industry has converted to the metric system years ago, probably much has to do with an international clientele base. I am now the oldest machinist in our shop, and was here prior to our company changing over to cnc equipment. The old equipment was all based on inches/feet, but all the newer equipment is metric. The younger machinists are very comfortable with metric, and I believe much of their training was based on metric. They are much more computer savvy than I am, so I still run the old equipment, and the younger men run the cnc equipment. I would have trouble doing their jobs, and they don't have much understanding or patience running equipment the old way where all settings are manually done.

In my own home shop, I'm comfortable with either metric or inches/feet. I think in inches/feet, and generally use that as a "go to" measuring method. This is probably because I grew up using inches/feet. This, IMHO, is where the resistance to changing to metric is.....those who learned using inches. I see this as a long road, but eventually everything will be metric. When all us older persons die off, and all the new tools, and equipment is in metric, the change over will be a natural course of evolution.

ooc
 
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An' Who'sa Gonna Pay

fer changing the gazillions of road and speed limit signs to them kilo meter things. eh? Ha! Bet all y'all didn't think about that in yer changin'.

Dang furiners . . next you know they'll be wantin' us all to be drivin' on the dang wrong side of the road . . .
 

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BTW, measurement of time is precisely defined by the SI standard in the same way as English units in terms of seconds, minutes, hours, etc. There are no units used for multiples of ten for anything longer than one second. But, decimal relationships are used for units less than a second (microsecond, nanosecond, ...). The reason is essentially the same as it is for the navigation exception allowed by the SI standard. It is because of the way that maps of Earth are defined in terms of degrees of arc and that a day is defined in terms of a solar day as opposed to a full turn in inertial space (referenced to the stars). A nautical mile is approximately one arc minute of latitude -- the relationship is approximate because the earth isn't a perfect sphere, so an arc minute at one latitude is not exactly the same it would be at another.
 
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I actually prefer metric for my work, maybe because even in the US for bicycles it is mostly metric. It's easier to use. When I have to work in fractions I like to go to decimal.
 
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Bob,
Yes the U.S. is best word--- "confused" about what measurement system to use. But it is inching (pun intended) toward SI units. I think it has more to do with just being different and a reluctance (read that stubbornness) to change.
As a former Science Teacher, I had the honor of teaching the metric system many times over and tried to impress the mathematical simplicity of the units and names--but was stymied by other science "educators that insisted teaching conversions thus making it a nightmare for the students. Interesting that all the major corporations are multinational and use the metric units in daily operations. I am proud to say that more than a few of my students have thanked me for making them learn the system.
I've since changed professions and am happy that medicine is metric for the most part--working on that too on a smaller scale. I'm perfectly comfortable with the SI system in my profession and shop, but do have Imperial tools available.
 
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I have a car and a truck. One German and one Japanese. Metric tools.One of my micrometers has a button to switch between inches and mm. My oneway lathe is metric yet I had a 1 1/2by8 spindle made for it. You talk cm and I am lost. mm and I think of spanner measurements. Anything more than about 19mm i have to get a ruler. Now I gotta admit the first time a fellow asked me to pass him the metric cresent wrench I had to think about it.
 

john lucas

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Kelly I have a metric Pipe wrench and slip jaw pliers if you ever need them. If you turn woods from a country that used the metric system should you use a gouge measured in millimeters vs inches.
 

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Most of our turning tools, chucks, and lathes come from other countries -- meaning, of course, that they're metric tools even though they may be marketed in the US with size stated in inches rather than millimeters. And, let's not forget that the figure-8 caliper are also metric. :rolleyes:
 
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