Do Americans use metric system?

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I worked in a paper mill for 22yrs, 20 of them running a Voith winder. We measured the width of the paper roll in millimeters and the diameter in inches
Possibly because the width of the roll can be changed and ordered in whatever unit you like, but the diameter is fixed by the machine that makes the roll. Rolls are similar to pipes and almost all pipes are made and ordered in "inches". However this is a nominal pipe size, historically things were done in inches so the dies and formers were in inches and the engineering was in imperial AKA inches. It is nominal because that is just a start point or a convenient "name". You make a large pipe in a former, but the critical dimension is the inside diameter which is obviously the outside minus twice the pipe thickness. Since there is a variance on wall thickness and a variance in sizing control you can order a "40 inch" pipe but the actual dimensions are not 40" and are as easily measured in mm as inches. In the same way almost all pipes are ordered to a minimum maximum length of circa 12.125m this is so they fit in and on 40' trucks and containers. From this most welding set ups have the machines set 12.125m apart which is 40' minus a bit
 
Freedom units v the metric system

Americans don't want our King but they love an imperial measure

Metric is easy and makes sense. InFerial is a total shambles and nothing correlates. And the Americans and British have different standards for the same unit just to "help" and maximise confusion.

The reason that the US gallon is different to the Imperial gallon is that when the US decided on the volume for the US gallon Britian had three different gallons in common use. The US chose the most common for the US gallon. Later the British standardised the Imperial gallon and naturally chose a different one to what the yanks chose.

See Numbered drills - wherefrom? - HomemadeTools.net for a summary of just one of the hundreds of InFerial measurement systems (and the source of the word InFerial). Add to that the are also several British wire gauges that are different to all the American wire gauges.

And then of course the brits have dozens of unrelated liquid measures like dramms and gills etc etc.

Barrels are one of my favorite US inferial units. There are seven different barrel sizes used in the USA, with the size being dependent on the contents. Their names and metric equivalents are as follows: US cranberry (95.5 liters), US dry (115.628 liters), US liquid (119.24 liters), US federal (117.348 liters), US federal proof spirits (151.416 liters), US drum (208.4 liters), US petroleum (135 kg.), US petroleum statistical (158.99 liters).
Obviously if one definition of a unit is good, seven must be seven times better. And of course there are British barrels to add to the confusion.

And the US loves its Tons, long 2240lb, short 2000lb, metric 2204lb (1000kg), shipping 40 cubic feet, deadweight (see below), etc etc.


Below is a simplified chart showing the major InFerial dimesions and their metric replacements.

 
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That's the simplified version??? I'm usually pretty good at deciphering charts but I can't make heads or tails out of that.
 
Ok, I get it now. It's just how many of each unit of measure does it take to constitute the next one indicated by the line/ arrow.
Pretty simple now that I see it.
And 4 poppyseeds to the baleycorn. Of course. Everyone knows that.
 
Ok, I get it now. It's just how many of each unit of measure does it take to constitute the next one indicated by the line/ arrow.
Pretty simple now that I see it.
And 4 poppyseeds to the baleycorn. Of course. Everyone knows that.

Now tell me without using a calculator
  • How many Palms to a Gunthers Chain, and
  • How many inches to a Nautical mile
Metric is just so easy.
 
I grew up in school with metric system so I don't need inches. Never learnt it.
I remember my father asking for a piece of cheese. I asked how much and he said eighth of an inch. I asked what the hell is that?

I don't know what big deal is with inches.

One shouldn't have an emotional attachment to a unit of measurement.
 
Now tell me without using a calculator
  • How many Palms to a Gunthers Chain, and
  • How many inches to a Nautical mile
Metric is just so easy.
Yes metric is much easier and in my opinion better in a practical sense but the twip, pica, and shaftment definitely hold the edge in entertainment value.
And by the way, I always thought a shaftment was the amount of money they take out of your check for taxes.
 
I Hate metric tape measures.
I did grafting for years in the US, inches.
Came to Oz, did draughting, metric, mm's.
But civilians talk metric in Centimeters!!!!!!! WTF.
Then when you use a tape measure, its in Centimeters / Meters.
Why can't it be in continuous measurements, like 90 then 1000, 1100, 1200???????
Instead of 90 then 1 then 10 again, gives me the shits.....
I wanted to order a piece of glass 120 x 350, he wanted hundreds for it!!!!!! WHAT????? That's a big piece of glass! What A2 size? Oh, you want millimeters!!!!!!
Then long ago I had an American engineer tell me metric was more accurate!!!!! Bwahahaha An inch is an inch, even at 25.4mm.
 
The only people who use centimetres are dressmakers, everything else is millimetres / meters.
Never heard anyone else use cm...
 
We got some rolls of meter wide steel from Canada once. It was great. I could make a joint of 10x8 without any waste. Or a half joint of 12x8 and a half joint of 8x8.
 
I can saw you a pipe 102 millimeters and be spot on. I can saw you a pipe
at 12 feet 3 and 5/64 of an inch and be spot on. So why is it easier if you
know both methods. Because YOU don't know both? I know both and can do
both. Neither one is better than the other, it's all in what you use. It's an attitude
that I see is the problem, not the measuring system. JMHO. John
 
I can and do use both, but metric is far easier to do conversions and multiples of.
 
The only people who use centimetres are dressmakers, everything else is millimetres / meters.
Never heard anyone else use cm...
Certainly not in UK, they take a very logical system and by switching between mm/cm/ and meters they manage to screw it up, usually by a factor of ten. They do the same in F1 and athletics, speaking in decimals of a second, thousandths then giving the actual number I frequently cant understand what on earth they are talking about.
 
I can do conversions and multiples also. 12 foot 3 inch and 5/64 of an inch is
147.0780". It's just a number and you can do anything you want with a number! John
 
The only problem some get into with the SI vs Ye Olde Englisher system is the British penchant to take the easy route when doing multiples of a measurement. Grab a piece of string/rope, its length matters not. Without doing any kind/type of measurement there is one point on the string/rope that you can find with perfect exactitude, i.e.: The Middle and the middle of that middle followed by the middle of that middle of that middle of that middle and so on.
That leaves you with the only way to express those halfs of halfs of halfs EVIL FRACTIONS!!!
While dividing something up into 1/10th (not easy to do) to give decimal fractions wherein it is at a glance obvious that 0.375 is less than 0.3906 it is not as obvious that 3/8 and 25/64 are related in the same way. If your 7/16 wrench is a bit too big what size do you try next? Obviously 5/16 is smaller but what about 3/8?
On the other hand if my 9mm wrench does not work it is obvious without thought to try 8mm or 10mm and I know without thought which is larger and smaller
The Non-Relationship of other measuring units like Volume units and Weight/Mass measurement is a separate issue.
Example: Without thought how big a box will hold exactly one gallon of liquid and if that liquid is pure water how much does it weigh?
 
If .4375 is too big obviously .375 is smaller. I'd whip out my Craftsman 3/8 inch open end! John
 
Hi,
As an engineer (naval architect) I'm used to both systems, but when doing my own calculations I will often use the system that I am most familiar with and then convert the results (especially in any spreadsheets that I write).

While I admit that the SI system has some nice features, to me it also has some drawbacks in that its hard for me to visualize some units (specifically pressure/pascals). As such I tend to prefer Imperial units for some calculations but will use SI for some others, and/or a mix for the rest.

Pat
 

I was schooled in both and have spent most of my working life on US aircraft with a few cival Fokkers and Brit military aircraft thrown in but I use metrics and decimals almost exclusively by choice.

When you have to turn down a piece of metal from 1" to 17/64 the first thing you have to do is convert that fraction to a decimal so your micrometer or vernier can measure it. The same for many other restoration processes such as working out the bend allowance for a 3/8 radius flange in a piece of metal and how far apart your rivets are when the drawing calls for 18 rivets in a 14 13/32 run.

Brit aircraft are like their inferial measurements - as my first training instructor put it the first law of British aircraft design is why make it easy when with a little thought you can make it bloody near impossible. Lets face it - nobody but the brits make different spanners for the same size bolt. Yes a 3/8 Whitworth spanner will not work on a 3/8 BSF bolt/nut becuase they have different head sizes (and yes I know BSF just uses a different BSW spanner) and unlike metrics it is impossible for the vast majoity of people to instantly calculate the number of inches in 1 mile one chain 1 foot 3 inches. Calculating the metres, cm or mm in 1.87549 km on the other hand can be done in a second by the average ten year old.

I do agree with Mike Wint though that creating fractions based on halves is much easier but outside of that metrics are so much easier because everything is a power of ten and all the measurements are related.
 
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