Imperial Gas meters ?

[alan_m]

Most pubs sell short measures so you are only getting half a litre beer.

[Davey]

I'm 64, and grew up with Imperial units, with metric as an aside. When industry started to get metricated, engineering drawings would have absurd values such as 5567mm, which meant absolutely nothing to me intuitively. I buy beer by the pint, and drive miles, at varying miles per gallon values. I have to convert the litres purchased into gallons, unfortunately. But I don't know of a standard unit of fuel consumption that uses litres and miles, so a conversion is needed somewhere. And the metric value of litres per hundred kilometres seems daft to me.

[Davey]

That depends on how well you know your barman. You, it appears, don't know yours very well. A half pint ordered is very often nearly a full pint delivered.

[Adrian]

So you did grow up with metric units?

Because you're used to "bigger number = better" "How far can I go on X fuel?". "How much fuel does it take to go X distance?" is, if you think about "I need to go from A to B, so how much fuel will it use?" just as intuitive, if not more so. And, when you think in terms of "How much fuel will I use?", "smaller number = better" also makes a lot of sense.

It's not like anybody ever says "Right, I've got a tankful of fuel, so today I'm going to drive half-a-tank-worth." People have journeys to make.

[Chris J Dixon]

With older pumps there used to be a mechanical number display on the side, which was the actual total gallons dispensed, and a multiplication factor which was close (but not equal) to 1. AIUI, because the pump accuracy was greater than the tolerance specified by Weights and Measures, it was possible to routinely dispense slightly less than was indicated. Not much, but enough to be worth doing.

Chris

[Chris J Dixon]

With planed timber, the difference between the nominal size and the actual dimensions are such that it probably doesn't matter what units you use. ;-)

Chris

[charles]

I still ask for 2 by 1.

[Davey]

That may be true, but how is it relevant to either mpg vs l/100kms, or pints of beer?

[Dave Plowman (News)]

Yes - I changed a BMW from those to 'normal' in the late '80s. And it seemed to make a vast improvement - far more than just by fitting new tyres.

[Martin Bonner]

A milli-parsec would be inconveniently large for measuring the perimeter of a screen. An atto-parsec would be a more sensible unit (about 30mm)

[The Other Mike]

A Mini mid 1990's has mainly UNC/UNF but with metric creeping in with the injection system and catalyst.

The flywheel retaining bolt throughout production 1959-2000 was a real one off

5/8" 16 tpi which is neither Whitworth, UNF, UNC, UNEF, BSF, nor anything 'standard' as far as I recall.

I have a sneaking feeling something else, maybe a coolant drain plug or the threaded spigot that went into the bottom of the thermostat housing to carry the bypass hose was whitworth.

[Adam Funk]

I didn't know about that. I was thinking about the pre-metric European units like the French "pouce" (literally "thumb").

Interesting.

[Adam Funk]

Would it have been possible to measure that difference (over 1 inch) with any instruments available in 1930?

[Roger Mills]

I'm assuming that the best instrument available in 1930 would have been an optical microscope. According to Wiki[1] this would have had a resolution no better than 0.2 micro-metres (about 8 micro-inches). The two "inch" standards only differed by 1.7 micro-inches - so you wouldn't have seen it on the microscope. You might just have seen the difference between two foot-long objects.

[1]

[Capitol]

Yes, interferometry works well far beyond those levels.

[Ron Lowe]

In the oil industry, I've come across tape measures in 'little inches' and 'big inches'.

Little inches are regular 1/12 of a foot. Big inches are 1/10 of a foot.

We oftern use decimal inches for measuring and tallying tubulars.

[Tim Streater]

Why are you assuming that?

[Davey]

I thought 'tubular' was an adjective?

[Mike Barnes]

Yes but it's a nounable.

[Davey]

????