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For those who use that 'imperial' measuring system

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Fractional vs decimal is not inherent to either the metric or imperial systems. It is fully possible to express something as being 0.678465645 inches long or something as being 4/9ths of a meter long.

In the end it doesn't matter where the unit is derived from its how easy it is to change between orders of magnitude.

When I want to know how many meters are in 1/3rd of a kilometer the basis of the meter doesn't even enter my head but the answer is immediately obvious. Can you tell me without hesitation how many yards are in 1/3rd of a mile? :)


What is a meter?

Since 1983, it has been defined as "the length of the path travelled by light in vacuum during a time interval of 1 299,792,458 of a second.

Where do you guys come up with this stuff :D


1km = 1000m = 100 000cm = 1 000 000mm

1mile = 5280feet = 63360inches

So 1mm = 1X10^-6km

and 1inch = 1.57828e-5miles

I love inches for their fractions, but that's where it ends. Fractions are incredibly useful things that we would be hopeless without. I just love how easy metric is and how much it make sense. From someone who grew up on metric, it's been incredibly hard to work out how the imperial system works and how to convert between the two.


I use both at work, and I used to hate metric... but I got used to it. Hell I even design in it now since getting into the 3D printing stuff.

I agree with PeteH though It all boils down to what you are accustomed to. But I think it must be worse trying to understand Imperial when you know metric though... all the fractions!

I like to point out how un-'marikan it is to use a system which harkens back to our dependence on our colonial overlords and how disrespectful it is to the ORIGINAL veterans of our country's establishing war. The usual excuse given by slack-jawed yokels for their distaste for the SI is that it began in France, which to a redneck is anathema. Most of them apparently choose to ignore ("are ignorant of") the role that the French played in, again, the Revolutionary War, and as a result probably don't deserve the freedoms (like the second amendment) won for us by the French generals who led our troops (like Rochambeau) and the French Navy fighting the sea war in the absence of an Independence force fleet.

As a practical matter, it's not as easy as it sounds to just up and get 300 million people to change the entire system of reference that the economy, 200+ years of history and at least a dozen good "yo mamma so fat" jokes are based on.

When designing products for DAGU, I try to make some allowances for the USA. As an example, I now use 3.5mm mounting holes so that they can use 1/8th screws instead of 3mm. However there is a limit to what I can do because our kits also sell to the rest of the world.

Recently one company asked me about supplying the kits with 4-40 screws? These UTS sized screws seem to be another "America Only" system. We could not find a Chinese manufacturer to supply us with these screws.

In the end we supplied the kit with no screws and let the customer add the screws themselves which is more work for them. This is one typical example where USA's dependance on the imperial system is costing them money.




Well I was brought up on imperial measurments back in the 60's, in the UK, and still use them today in Model Engineering as most of the plans seem to date from the late 30's onwards.  For work however ( a draftsman in town planning) I am purely metric.  At the end of the day it really boils down to what you are used to.  Just to confuse things though I use a metric calibrated lathe for the ME.