Imperial Gas meters ?

[Chris French]

Isn't that what 'our' inches are anyway?

[Adam Funk]

Oh, I have heard of that.

[Adam Funk]

Several layers of duct tape to make up the gap?

[Tim Watts]

No - they really do use a phrase that literally translates as "English Inches".

They used to have Chinese Inches (32mm) back in the day and there were

10 to a Chinese Foot (which is almost an Imperial foot at 32cm). 5 Chinese Feet to a Chinese Pace.

There are other named units with lots of factors of 10 both up and down from an Ch Inch, which is interesting that they managed to get a strong decimal flavour in so long ago.

[Roger Mills]

On further research, it appears that they are *now* - but haven't always been so. Prior to about 1930 'our' inch was 1/36 of an Imperial Standard Yard - and differed from 25.4mm by about 1.7 parts per million.

You probably wouldn't notice it on your average tape rule!

For further details, see

- particularly the part entitled "Modern standardisation".

[Adrian]

Very few people still working today were working at the time - so almost

100% of the workforce was taught in metric for at least _some_ of their education.

[Adrian]

See also: UKIP.

[Adrian]

Michelin TRX runflats - they were deliberately a different and incompatible size, because the bead shape was incompatible with "normal" rims and tyres.

[Dave Plowman (News)]

Don't think they were run flats. It was an early way of making a low profile tyre without ruining the ride. Completely. They may have made a run flat version, though. I had them on a BMW - they could certainly go flat. Changed the wheels to use standard tyres as TRX cost a fortune.

[Mike Barnes]

And: The USA.

[Andrew Gabriel]

Used to amuse me when we got Sun monitors delivered. The box would say something like: UK 24", US 27".

It was the same monitor, just that EU requires the diagonal to be of the viewable area, whereas US still allowed the diagonal to be to the corners of the screen/tube.

[The Natural Philosopher]

the purpose of standards is not to be the 'right' standard but to be *a* standard.

It doesn't matter if you measure the screen perimeter in milli-parsecs, as long as everyone else does.

[John Rumm]

Standardised timber lengths are typically in 300mm (i.e. 1') multiples. Hence 1.8m, 2.1m, 2.4m etc. So a bit of both. Timber thickness's are typically in something like 1/4" multiples. (although I don't think UK suppliers go in for US style "board feet" volume measurements).

[Adrian]

Sorry, you're right. Brain-fart.

315, 340, 365, 390, 415mm rim diameters, and tyre widths ending in zero rather than five.

If you think they were steep back in the day, you do not want to even _ask_ now...

[Tim+]

I had those on my first new car, an AlfaSud. Turned what was reputedly a fine handling car into a nervous twitchy thing with dreadful torque steer, tram lining and lift off oversteer. Awful things.

Tim

[Davey]

Being taught it and being comfortable using it are different things. I was taught Latin, but that doesn't mean I can hold a conversation using it. An engineering colleague of mine called the process of converting to metric: "metrifuction". I think he spelled it differently, though.

[Chris French]

In message , Davey writes

But, being comfortable using a system of measurement is really just about using it enough (assuming that it's not stupid and crazy).

Actually, you can say the same about Latin, and other languages as well.

[Scott M]

For the "real world" I (age: 41) find it a lot easier to deal in feet and inches and put it down to whole numbers of easily imaginable things. A foot is a biggish thing, an inch a smallish thing. Come to heights and

5'5 to 6'4 covers 95% of the populace with a nice granularity of 11 units. 1.651 meters to 1.930 seems either too course (1.6/1.7/1.8) or too fine (1634mm /1847mm / 1820mm) to my mind.

(This isn't to say I eswchew mm at all; use it all the time for small stuff.)

My lathe is 1947 vintage and find thou's a fine thing to work in. Call it 40 thou to the millimetre and wangling 1/2mm off the diameter of something is to take 10 thou off its radius. No going near fractions of inches at all :-)

FWIW, most casual lathe users make stuff "to fit" rather than to measurements as most jobs are one offs and there's no need for grommit A to fit anything other than shaft B.

[Adrian]

Well, quite. You're already swapping backwards and forwards.

If fractions of an inch are so sensible, why are you not working from

1/25" to the mm? And if decimals are so sensible, why not reach for a 0.375" spanner?

[alan_m]

I'm approaching retirement and my early education used metric units.