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at what temp we have a super conductor now these days???

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jpanhalt said:
If you are in a positition where its important that you know the difference, you should be able to do the conversion. John

i do agree with you on this one
but it'a pain in the ass if you have the differences like liter, imperial gallon, the normal gallon
or in pressure PSI, Newton square cm, pascal or colum of water in meters
(these are the conversions i normaly work with in my work)
if you go to the weight than sudenly in great brittain you don't weight kilos or pounds but stones

Robert-Jan
 
jpanhalt said:
If you are in a positition where its important that you know the difference, you should be able to do the conversion. John

i do agree with you on this one
but it'a pain in the ass if you have the differences like liter, imperial gallon, the normal gallon
or in pressure PSI, Newton square cm, pascal or colum of water in meters
(these are the conversions i normaly work with in my work)
if you go to the weight than sudenly in great brittain you don't weight kilos or pounds but stones

Robert-Jan
 
jpanhalt said:
If you are in a positition where its important that you know the difference, you should be able to do the conversion. John

i do agree with you on this one
but it's a pain in the ass if you have the differences like liter, imperial gallon, the normal gallon
or in pressure PSI, Newton square cm, pascal or colum of water in meters
(these are the conversions i normaly work with in my work)
if you go to the weight than sudenly in great brittain you don't weight kilos or pounds but stones

Robert-Jan
 
jpanhalt said:
If you are in a positition where its important that you know the difference, you should be able to do the conversion. John

i do agree with you on this one
but it's a pain in the ass if you have the differences like liter, imperial gallon, the normal gallon
or in pressure PSI, Newton square cm, pascal or colum of water in meters
(these are the conversions i normaly work with in my work)
if you go to the weight than sudenly in great brittain you don't weight kilos or pounds but stones :confused:

Robert-Jan
 
rjvh said:
Papabravo said:
We tried going metric in the 1980's and it was a disaster.

i asume we is USA
why it was a disaster???
Australia did the same thing somewhere in the 60s or 70s with not to much problems
Yes it was the United States. The scientific community was behind it. The auto industry was OK with it. Aviation fought it tooth and nail. Worldwide all altimeters are in feet and only feet. English and feet are still the language of Air Trafic Control. The beverage industry was OK with it. The resistance came from ordinary people who refused to get on board.
 
rjvh said:
i do agree with you on this one
but it'a pain in the ass if you have the differences like liter, imperial gallon, the normal gallon
or in pressure PSI, Newton square cm, pascal or colum of water in meters
(these are the conversions i normaly work with in my work)
if you go to the weight than sudenly in great brittain you don't weight kilos or pounds but stones
Robert-Jan

hi,
Its illegal to sell produce in the UK, using Stones and Pounds.
The UK started going metric in the 1970's.. as you may know the money is also in decimal.
Can you imagine the problems UK engineering students had working in FPS [foot-pound-seconds] and Pounds, shillings and pence. using a slide rule.:eek:

For one, I am well pleased that we use the metric system.:)
 
ericgibbs said:
hi,
Its illegal to sell produce in the UK, using Stones and Pounds.
The UK started going metric in the 1970's.. as you may know the money is also in decimal.
Can you imagine the problems UK engineering students had working in FPS [foot-pound-seconds] and Pounds, shillings and pence. using a slide rule.:eek:

For one, I am well pleased that we use the metric system.:)

You obviously live in a different UK :p

If you go to the butchers or the supermarket, it's common practice to buy food in pounds and ounces as well as grams, all the road signs are in MPH as well - we're only partially metric.

Obviously as the older generation die out the young ones growing up have never used non-metric measurements - except for miles!.

I've never used slide rules - I've always found them completely useless - an 'educated guess' at best. I found it far easier, faster, and more accurate to use a log book!.
 
rjvh said:
Papabravo said:
[ Aviation fought it tooth and nail. QUOTE]

smells like it was a NASA conspiracy to keep the foot mesurements :D
I don't think NASA had anything to do with it. More like pilots and air traffic controllers. How many accidents would you be willing to tolerate in the changeover?
 
Nigel Goodwin said:
You obviously live in a different UK :p

If you go to the butchers or the supermarket, it's common practice to buy food in pounds and ounces as well as grams, all the road signs are in MPH as well - we're only partially metric.
Check you super market packaging,

Obviously as the older generation die out the young ones growing up have never used non-metric measurements - except for miles!.

I've never used slide rules - I've always found them completely useless - an 'educated guess' at best. I found it far easier, faster, and more accurate to use a log book!.

Hi,
I suggest you look at this:
https://news.bbc.co.uk/1/hi/england/2129528.stm

Also Google for the weighing regulations.:p

Ref the slide rule, perhaps Mr Reginald Mitchell [Spitfire designer] wouldnt agree with you, most of calculations were done with a slide rule.:rolleyes:

Really Nigel.!

EDIT:
Doing further reading highlights a complete debacle over imperial versus metric in the UK.
 
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Regulations don't mean a great deal at all, and the use of imperial measures is more common now than it was five years ago when that article was printed. His only fault was selling ONLY in imperial, everywhere else lists both imperial and metric, and you can buy in either. Personally I've never asked for a kilo of anything, I always ask in pounds and ounces, I've never had a query from shop staff at all.
 
ericgibbs said:
hi,
Its illegal to sell produce in the UK, using Stones and Pounds........

Not quite, it's illegal to NOT display a price in metric. Produce can be priced and sold in any other units.
(bbc news: "The European industry commissioner has ruled that imperial weights and measures can be displayed indefinitely alongside metric measurements"

Metric units have been legal in the Uk since 1873.

There was a Metrication Board from 1969 to 1980 to encourage UK industry to go metric. One of the immeadiate results of this board was decimalisation of the UK pound. Car engine capacities were in cc (or litres) well before.

There are still plenty of exceptions to using SI:
Road signs in miles.
Car fuel consumption in mpg - we don't understand Litres/100km.
TV and computer screen sizes in inches
Weight is often given in stones (14lb=1 stone)
The yard is used for meassurement of some traditional games pitches (cricket, football) even in metric Australia, Canada and India)
Petrol stations in the UK switched from gallons to Litres when petrol broke the £2/gal ($3.3/USgal*) barrier. (We are now near £5/gal($16.7/USgal*) - £1.10/Litre)

A problem with traditional units was their inconsistency: There were local variations for every unit: every town had their version of a 'foot'
Miles: Nautical= 6080' (US Nautical= 6000'); Statute mile= 5280'; Irish= 6,721'; Scottish= 5,951', etc)



USA and UK are introducing metric by a 'progressive phase in'. India used a 'phased changeover' between 1960 and 1962. This was so succesful that other former British Empire nations used this, the last was the Republic of Ireland which changed over in 2005. (There has not been a sudden large increase in road accidents due to road signs being changed to kph or the signs in neighbouring Northen Ireland staying in mph)

Some countries have metricised their traditional units. On European mainland one can find goods being sold in "pounds" (500g) and "pints" (500ml).

A major benefit of SI is that the units are all consistant. There is only one version of each unit
Even in fully metricated countries there are exceptions: EG not all use the SI yyyy-mm-dd format for date.

There does seem to be an aversion to 'foreign' among the anglo saxons.

* 1 US gallon = 0.832673844 Imperial gallons; 1 £UK = $2 US
 
Nigel Goodwin said:
Were engine capacities ever not in cc's ? - I've never seen anything specified differently, and I've had experience on some VERY old motorbikes.

It seems that cars were described in horse power before being described in terms of capacity (litres or cc).

Thanks to the various 'Locomotive Acts' from 1861 and the turnpikes charging massive tolls for horseless carriages, the car was effectively stiffled in Britain. It wasnt untill the Locomotive Act of 1896 that the car was finally 'emancipated'. Even then the max speed was 12½ mph.

This means that Britain had been left well behind while developement of the car went on in (metric) europe and from which cars were imported.



Threads - the US car industry was opposed because it didn't like metric threads. This was why metric thread pitches were changed in the early 70s and we had metric fine (to 1970) and now metric coasre (after 1970).



Plumbing: The British approach to standardisation is 'interesting': We have metric standards that also incorporate imperial sizes. EG for waste pipes:

There are 2 BS numbers:
BS 5254 PVC (Solvent)
BS 5255 Polypropylene (Push Fit)

European ENs were introduced around 2000 or 2001

BS EN 1329-1 Unplasticized polyvinyl chloride (PVC-U) BS 5255 MUPVC Thick walled fittings only
BS EN 1451-1 Polypropylene(PP) BS 5254
BS EN 1455-1 Acrylonitrile butadiene styrene (ABS) BS 5255
BS EN 1519-1 Polyethylene(PE) BS 5255 - Table 2 sizes
BS EN 1566-1 Chlorinated polyvinyl chloride (PVC-C) BS 5255 MUPVC Pipe and thin walled fittings

BS are still available in both imperial and metric sizes.
EN fittings include metric sizes used in Europe but which had not been used in UK

The EN fittings are to outside diameter
Pipes also have a stiffness rating which relates to the thickness of the pipe wall.


The above means that you can't be sure if you can join new pipes with existing ones. You can't even be sure that you can join new pipes of one make with those of another make. It's best to renew a whole run and to buy all your pipes and fittings at the same time. (fortunately plastic fittings are fairly cheap compared to metal fittings)
 
CheapSlider said:
Threads - the US car industry was opposed because it didn't like metric threads. This was why metric thread pitches were changed in the early 70s and we had metric fine (to 1970) and now metric coasre (after 1970).

I went past "Joseph Whitworth's" house today (as I often do), it's now a hotel, I work about 3 miles from it. Not surprisingly we've got "Whitworth Road", "Whitworth Avenue", "Whitworth Hospital".

Around here is a VERY historic part of the country, and is often considered the birth place of the industrial revolution - and relevent parts have been given world recognition.

But I thought the American used AF threads?.

I've got an old spanner in my pocket at work, I found it in the garage at work, all rusty - it's a Whitworth sized open ended spanner, and it fits almost every nut I ever come across at work :p
 
Nigel Goodwin said:
But I thought the American used AF threads?.

I've got an old spanner in my pocket at work, I found it in the garage at work, all rusty - it's a Whitworth sized open ended spanner, and it fits almost every nut I ever come across at work :p

It's NF (national fine).

My lathe is all Whitworth threads (Smart & Brown, ca. 1966). It's a great profile and very strong. Threads don't srip out as easily as they do with the 60° standard. Unfortunately, the 60° thread prevailed. There is one place where Whitworth survives, I am told. That is for the objectives on microscopes. Just FYI.

John
 
Nigel Goodwin said:
Were engine capacities ever not in cc's ? - I've never seen anything specified differently, and I've had experience on some VERY old motorbikes.
When the Beach Boys sung poetically about their '409, it was cubuc inches not cc's
 
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Papabravo said:
When the Beach Boys sung poetically about ther '409, it was cubuc inches not cc's

Don't know the song, but I was referring to the UK, where we've always used cc's - good point from CheapSlider about using horsepower previously though!.
 
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