Metric Anyone?

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dr wogz

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Due to the popularity of "coins" in another thread..

What's everyone's take on Metric?

Seeing that the US is one of three contries that don't use the metric system (or SI), curious to know if you do see a need, a want, or notice that metric does creep into your lives..

(Yes, a few other counties dont' use the Metric system either, but they are officially "metric' and seem to adapt either because the US is their biggest trading partner [Canada], or that it isn't all that well enforced [England])

I, a Canadian, have a hard task.. I need to design with Imperial (feet, inches, pounds) in mind, while adapting to metric for "off continent" work. (I usueally get funny 'imperial' dimensions, or funny 'metric' dimensions, depending on which way I'm going..
 
The average non-engineering student/graduate American will resist this as they have every other change:

Digital TV converter boxes: "WE need an infinite time extension"....

Dollar coins.

Counting by 10 (metric) instead of by 12, 36, 5280, etc.

"Royale with cheese"......:eek:
 
The problem here in the U.S. is we never adopted a set of milestones to help us turn over from imperial measurements to metric. It took other countries upwards of 20+ years to get there, but they had a plan and goals to reach.

Should we go to metric, most definitely! Do we have metric systems already in place, yup - look out our currency.
 
The problem here in the U.S. is we never adopted a set of milestones to help us turn over from imperial measurements to metric. It took other countries upwards of 20+ years to get there, but they had a plan and goals to reach.

Should we go to metric, most definitely! Do we have metric systems already in place, yup - look out our currency.

The way kids are now, I don't think we can make the change. As a current high school student, I go to school with kids who don't know how many feet are in a mile or how many quarts are in a gallon. For a bunch of 14-18 year olds, that's just sad.
 
Intruder, when I was your age :eek: there was a major push in school to teach the kids the metric system. We even watched a series about it. (The only thing I remember from the show is part of the opening theme - "A liter, it's a little more than a quart").

For what it's worth, metric would be easier - how many feet are in a mile? 5280. How many pints in a gallon? Eight. How many ounces in a pound? Sixteen. How many meters are in a kilometer? A thousand. How many milliliters in a liter? A thousand. How many grams in a kilogram? A thousand. See how easy it is?

Now, if any of you are members of the MicroMaxx Yahoo group, you could read a very interesting discussion of metric v imperial as it relates to model rocketry.
 
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The way kids are now, I don't think we can make the change. As a current high school student, I go to school with kids who don't know how many feet are in a mile or how many quarts are in a gallon. For a bunch of 14-18 year olds, that's just sad.

I agree. The change utterly failed in the 70's, and it would be even worse now. I remember learning it in school. I told my father about it, and he was yelling "We're American, and nobody is going to dictate anything to us! You kids shouldn't be learning this **** in school." Then he went to the school board and demanded they stop teaching it or he was going to sue them. They stopped soon after.
 
I for one prefer metric for some things and imperial/standard/whatever for everything else.

I like metric for rocketry. I often use millimeters and centimeters because it's SO much easier dealing with an easily divisible whole number rather than fractions. More accuracy and less trouble/mistakes. Makes sense for the same reasons it makes sense in engineering.

Now for travel distances, weight, and area measurements, I prefer standard over metric all day long. I can easily picture how far away something is if someone says "eight miles" or "100 miles" and I can easily estimate distances for someone else, IE telling them to drive 4 miles, turn left, go another 1 1/2 miles, turn right, etc. Not so with metric... if someone told me to drive 12 kilometers and then turn right and go 3 kilometers I'd be lost. Same thing when measuring acreage on the farm... I can look at a field and guesstimate how many acres are in it... 12 acres, 20 acres, etc. Hectares (metric area unit) are too big and don't correlate well with acres, so again, if someone says they have an 8 hectare field they need cut, that's rather meaningless until you convert it to something you understand.

Reading on www.nasaspaceflight.com forums has taught me that the metric ton (1000 kilos) makes a lot more sense and is easier to use than short and long tons (2000 lbs and 2200 lbs) but again, what's 1000 kilos?? I have to convert it into pounds to know what kind of weight I'm looking at... Same thing with liters and volume measurements...

It's a matter of convenience more than anything else... I'm sure if we HAD to adapt, we could, given time, but there would be a WHOLE LOT of confusion for a good long while!

Don't even get me started on metric hydraulic fittings, metric bolts and fasteners, and metric threads... those are ABSOLUTELY INFURIATING and standard bolts, nuts, fittings, and fasteners are superior in every sense of the word... and metric hydraulic fittings are harder to find than hens teeth!!! (pitfalls of owning a German combine!)

Later! OL JR :)
 
I agree. The change utterly failed in the 70's, and it would be even worse now. I remember learning it in school. I told my father about it, and he was yelling "We're American, and nobody is going to dictate anything to us! You kids shouldn't be learning this **** in school." Then he went to the school board and demanded they stop teaching it or he was going to sue them. They stopped soon after.
:confused: The metric system is used by every country on earth except the US , Liberia and Myanmar. It is simply a better system. The above reaction seems to typify most of the opposition I have heard from relatives and friends and has never ceased to amaze me.
Cheers
fred
 
Working in a laboratory, I use metric all the time. It has become second nature. About the only time I still use english is when designing my model rockets, because everyone else uses that for most measurements. Except, of course, NAR competition, which does use metric and tends to screw everyone up when they try to make the conversions.
 
The problem here in the U.S. is we never adopted a set of milestones to help us turn over from imperial measurements to metric.

Well to be technical the U.S. doesn't use imperial measurements, we use United States customary units, which differ in some areas from Imperial
 
Intruder, when I was your age :eek: there was a major push in school to teach the kids the metric system.

The first quarter ( sorry 25%) of my 7th grade science class in 1966 was devoted to learning the metric system. The U.S. HAD to think metric or by the time the magical year of 2000 came along we would be a third world country. I appreciated that marking period though I have forgotten a lot, but I work mostly in the metric system at work.
 
The way kids are now, I don't think we can make the change. As a current high school student, I go to school with kids who don't know how many feet are in a mile or how many quarts are in a gallon. For a bunch of 14-18 year olds, that's just sad.

I have worked with more than one engineer in my time who had trouble reading a tape measure or adding fractions. Not long ago I asked a kid just out of college to get a 9/16" wrench out of the tool box for me. when he didn't come back with it I looked over to find him looking at 1", 1and1/8" 1and 1/4" ect, he had no idea it would be right next to the 1/2" in the rack
 
Prefer to use metric in a lot of things, including rocketry. When I'm up-scaling I found that it's easier to do the math in metric. When ever math is involved of course metric is easier. And I prefer metric fasteners on cars.

Reminds me of one Abe Simpson,

"The metric system is the work of the devil! My car gets 40 rods to the hogshead and that's the way I likes it!"
 
I would love it if AT LEAST the rocket community would use the metric system exclusively. It sounds really dumb (to me anyways) to say something like, "Well...I've got a 54mm motor in this 4" diameter bird."

I am constantly finding myself using the metric side of my ruler for measuring out fins, cutting tubes, etc.

-Dave
 
I would love it if AT LEAST the rocket community would use the metric system exclusively. It sounds really dumb (to me anyways) to say something like, "Well...I've got a 54mm motor in this 4" diameter bird."

I am constantly finding myself using the metric side of my ruler for measuring out fins, cutting tubes, etc.

-Dave

It's very odd. When I'm building a scale model, I calculate the size of everything in millimeters so I can achieve the desired accuracy. When I'm designing a sport model, it's all inches and fractions.

Soft drinks come in 2 liter, 1 liter and half liter bottles as well as 12 ounce cans and 20 ounce bottles, so we're not the only ones who can't stick to one set of units.
 
Dunno what's worse... using (so called) "English" (we call it "imperial"), or using a complete mix of units.
Miles, Miles per Gallon, but fuel has only been sold in litres since about 1980. And yes people do recalculate the pence per litre price back into pence per gallon to compare with the prices 30 years ago rather than just comparing this week's number on the sign with last week's/month's number :eek:
 
We are long overdue for the change to the metric system. Interestingly, all of my classes at the university uses the metric system, physics, geography, engineering, etc.

We should have changed over to it by now.

My 2 cents,
Mike
 
UK went metric

but

everyone in the UK does distance by miles
we order beer in pints

and that just will not change.
 
The average non-engineering student/graduate American will resist this as they have every other change:

Digital TV converter boxes: "WE need an infinite time extension"....

Dollar coins.

Counting by 10 (metric) instead of by 12, 36, 5280, etc.

"Royale with cheese"......:eek:

I have to agree Fred:
The Better 2/3rds gets on me all the time about using metic jargon with her..."In english please, I don't Speak Metic." she'll quip.
Frankly we Americans use what we're most comfortable with I believe. I personally switch back an forth with whatever is needed for the job at hand. But having spent most of my adult life collecting tools and instruments using English measure I'm really not inclined to spend another small fortune replaceing them.

Being a long time coin collector of sorts. I firmly believe the dollar coin will NEVER fly as long as the government keeps trying to make them the size of a quarter 1.04" (26.5mm):D Make them the diameter of the Old time silver dollars 1.5" (38.1mm), folks might use them. Yes; I know the old Eisenhower Dollar wasn't very popluar as a coin, but at least they weren't confused with a quarter (Carters Quarters) the poor old Susan B. Personally I'd sure like to see the mint bring back the Beautiful Morgan Silver Dollar, which I believe was our "best ever" coin.

Sorry to get off topic a bit but those goofy quarter size dollar coins have bothered me since their creation.
 
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Dollar coins are not the same size as a quarter. This is an urban legend that will not die.

https://www.usmint.gov/about_the_mint/index.cfm?action=coin_specifications

They are 43% larger than a quarter (by mass) and the weight difference between a nickel and a quarter is less than a quarter and a dollar.

The biggest problem with the SBA was that sighted people who only glanced at their coins would see a silvery coin with reeded edges and assume it was a quarter since they were not yet used to having a small dollar coin. All of the Golden Dollar coins solved that problem.

A large eisenhower dollar sized coin is too heavy, too expensive to mint and will never work in normal vending machines, so that will never happen.

What most people do not realize, is that even though the paper dollar is still produced, the dollar coins are circulating in larger numbers than ever before in US history. Sure, not as much as quarters or paper dollars, but still in pretty big numbers. Even before the Presidential series started, the Sacagawea was far more successful at circulation than the Eisenhower coin.

Anyway, I'm sure there are plenty of Canadians who are amused and amazed by our inability to embrace a small doallar coin that is a different color than our other coins and says "$1" on it.

I have to agree Fred:
The Better 2/3rds gets on me all the time about using metic jargon with her..."In english please, I don't Speak Metic." she'll quip.
Frankly we Americans use what we're most comfortable with I believe. I personally switch back an forth with whatever is needed for the job at hand. But having spent most of my adult life collecting tools and instruments using English measure I'm really not inclined to spend another small fortune replaceing them.

Being a long time coin collector of sorts. I firmly believe the dollar coin will NEVER fly as long as the government keeps trying to make them the size of a quarter 1.04" (26.5mm):D Make them the diameter of the Old time silver dollars 1.5" (38.1mm), folks might use them. Yes; I know the old Eisenhower Dollar wasn't very popluar as a coin, but at least they weren't confused with a quarter (Carters Quarters) the poor old Susan B. Personally I'd sure like to see the mint bring back the Beautiful Morgan Silver Dollar, which I believe was our "best ever" coin.

Sorry to get off topic a bit but those goofy quarter size dollar coins have bothered me since their creation.
 
When I was in school in the 80's the metric change was coming fast. we delt with not only in sciences but math spending long hours converting back and forth. Now a days I cant remember much at all. I have had to go and relearn alot and even downloaded a few programs to help me keep refreshed.
 
I have some personal experience with the metric system...

I work in road construction as an inspector. Essentially, I tell large, ornery road workers when they are doing their job wrong. A few years ago the Michigan Department of Transportation (MDOT) converted their system of measurement exclusively to metric in 1996. It worked okay on the state jobs once the contractors got used to it. Many of the workers still converted many measurements to feet but after a while they got used to the idea of "meter" and "centimeter."

All of this would have worked great except for two things:

1. The conversion was done haphazardly. Roads are typically built to whole feet measurements to make calculations easier and quicker. So for example an all season county road might have 11 foot lanes, 4 foot paved shoulders and 4 foot gravel shoulders. MDOT in all their infinite wisdom converted not to easy to remember whole numbers but converted them straight so instead of 11, 4 and 4 you had 3.352, 1.219 and 1.219. MDOT did this for EVERYTHING. Contractors, engineers and surveyors found this tremendously annoying as it slowed all of the calculations needed in this work. So MDOT caved into all the whining and in 2003 converted back to the english system. :mad:

2. While MDOT was doing everything in metric almost NONE of the municipalities in Michigan such as cities, counties, etc. were working in metric. So a contractor could spend a summer working one month on a state metric job and then work the next month on a "local" job designed entirely in english. This only managed to set everyone's heads spinning and gave more ammo to the "pro-english" crowd.

The argument I commonly hear is, "English has worked for the US of A for over 200 years. Why change now?" Guess what, those that say that are VERY opinionated and they vote religiously. So anyone that wishes to convert the U.S. to metric I wish you the best of luck - you're going to need it.

-Dave
 
My latest build is 55" tall and to say it is 140 cm seems unnatural. Working with 8ths, 16ths and 32nds of an inch isn't all that difficult. Just need to use your brain a little. Yeah the slug is pretty cool too from an historical perpsective.
 
Dollar coins are not the same size as a quarter. This is an urban legend that will not die.

https://www.usmint.gov/about_the_mint/index.cfm?action=coin_specifications

They are 43% larger than a quarter (by mass) and the weight difference between a nickel and a quarter is less than a quarter and a dollar.

The biggest problem with the SBA was that sighted people who only glanced at their coins would see a silvery coin with reeded edges and assume it was a quarter since they were not yet used to having a small dollar coin. All of the Golden Dollar coins solved that problem.

A large eisenhower dollar sized coin is too heavy, too expensive to mint and will never work in normal vending machines, so that will never happen.

What most people do not realize, is that even though the paper dollar is still produced, the dollar coins are circulating in larger numbers than ever before in US history. Sure, not as much as quarters or paper dollars, but still in pretty big numbers. Even before the Presidential series started, the Sacagawea was far more successful at circulation than the Eisenhower coin.

Anyway, I'm sure there are plenty of Canadians who are amused and amazed by our inability to embrace a small doallar coin that is a different color than our other coins and says "$1" on it.

BS Fred!
With the gold color coins .042" (2.24mm) in diameter larger then a quarter there just isn't enough difference to be useful. How many people can tell, "feel" a difference of 3.4g? That little "mass" difference doesn't cut it either.

While the larger 1.5" coin may be a bit more to produce it'd be worth it, vending machines and parking meters slots can and should be changed just as easily as making these useless coins.

Sure they my be releasing more of the "golden Dollars" but we're not seeing them in circulation! WHY? Because Collectors are snatching them up just like they have with all the other NON used issues. They like the SBA and Sacagawea gold dollars will simply fall into collections and be ignored by the public. The only place I can get gold dollars on this side of the country is at the post office or a bank. I've YET to see one used as Change anywhere.
I really think that's why the gov decided to issue the presidental dollars...cause the Sac gold dollars have been such a bust.

They haven't changed the size of the half dollar, why the heck should the dollar coin be smaller? Damned STUPID IDEA if you ask me! Shoot even the Euro coins at least have a logical size difference.
 
They are in circualtion, but you are just not seeing them personally. And again, they do not circulate as a replacement for the dollar bill - they circulate where they are used: tranist systems, vending operations that supply them in change for larger bills, coin-op laundry, many parking operations (lots and meters), self-car wash, etc.

The circulation info is from the Federal Reserve and the last report I saw showed them circualting (in/out, not just new coin passing through as your 'collector' scenario would imply) at a very good rate and totally eclipsing the Eisenhower.

The current dollar coin feels nothing like a quarter. It is 43% larger. It is larger in diameter and thicker and has a different edge and a different color. It can be felt and seen as different. Let's try an experiment: carry around a few quarters and golden dollars in your pocket for a week or two. Maybe 3 of each coin. After the week or two of reaching in your pocket to feel them and see if you can tell the difference, tell us if you rapidly realized how different they are or if you still maintain the the two coins that are 43% different and different color and with different edges are "identical".

If you cannot tell a coin that is 43% larger and a different color from another, then you cannot handle paper currency as it is all the same size. Oh, wait, the government lost that case in court and has to pay the attorney fees on that as well. The next pahse of currency redesign will be interesting. Most likely there will be new sizes for all denominations (OK, they may keep one of them they same and change the others.)



BS Fred!
With the gold color coins .042" (2.24mm) in diameter larger then a quarter there just isn't enough difference to be useful. How many people can tell, "feel" a difference of 3.4g? That little "mass" difference doesn't cut it either.

While the larger 1.5" coin may be a bit more to produce it'd be worth it, vending machines and parking meters slots can and should be changed just as easily as making these useless coins.

Sure they my be releasing more of the "golden Dollars" but we're not seeing them in circulation! WHY? Because Collectors are snatching them up just like they have with all the other NON used issues. They like the SBA and Sacagawea gold dollars will simply fall into collections and be ignored by the public. The only place I can get gold dollars on this side of the country is at the post office or a bank. I've YET to see one used as Change anywhere.
I really think that's why the gov decided to issue the presidental dollars...cause the Sac gold dollars have been such a bust.

They haven't changed the size of the half dollar, why the heck should the dollar coin be smaller? Damned STUPID IDEA if you ask me! Shoot even the Euro coins at least have a logical size difference.

So you are opposed to "the dime"? Why is it so small? it should be bigger than a nickel according to your 'plan'.

you should know why the traditional coin sizes were set: they were based on the type of metal used and the amount of that metal - it's value in the good old days. Those days are long gone. Paper money no longer says "will pay the bearer on demand". paper currency bills are now just "note" and are not "certificates". Coins are just tokens.

And nobody is going to accept 19 Eisenhower sized coins as change from a post office vending machine for a $20. The logical people on planet Earth have selected sizes for coins that are easy to handle. The 1 and 2 euro coin, the 1 and 2 dollar Canadian coins, etc.
 
Alright, speaking of money, how long till paper or coin money is no longer used? I predict that that day will be here within 30 years. Hopefully, by then, we will be on the metric system at last.

Mike
 
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