Since when did 3/8" = 9.2mm?

aaah, depends....
I had some expertise and experience with the reason they modified the Cemetery Regulations in Victoria, in a past life while investigating irregularities in the burials at the Melbourne General Cemetery where for various reasons the Cemetery staff allowed some weird practices like strata burials in re-used ground and public burials where we found 21 coffins squeezed into spaces with memorials on them and several graves in reuse areas where we rodded the graves to find the last coffin interred had about 21 inches ground cover. After six months of investigation and finally getting confessions from staff we charged the Secretary and office staff with various offences, but not with breaches of the Cemeteries Act as you had to be an authorised person to lay charges under that Act. When the Cemetery Trust was likely to be sacked they resigned enmasse. When the Springvale Cemetery Trust took over the administration of MGC special amendments were made to retrospectively alter the legal minimum burial so that the re-use and built up areas were legal. The investigation file we submitted was about 14 inches high when the two of us completed the investigation! That was a long time ago. in the mists of time.

Ken
 
Interesting, remember that fiasco, although, as reported in the press I seem to recall that the whole place was being 'run' by a particular funeral director firm ? They were putting them in the pathways 'n all, anywhere they could squeeze an extra in. Fees there would have been pretty high compared to the 'burbs.
It was common practice in the big inner-city places to 'reclaim' ground by bringing in mountains of fill. In SA, I think, removal of remains to a lower level in the same spot isn't unusual - damn difficult in Vic .

Bob
 
TVs have been measured in inches again for a very long time. And now they are so big that you have to do a mental conversion to feet and inches in order to visualise the size, if you're not actually looking at it.
Another weird thing about US measurements. Have you noticed that they don't appear to use tons? They just use pounds. So they will state a ship's weight in thousands of pounds. Very hard to get your head around.
I recall reading an American technical magazine about 45 years ago. It might have been Scientific American. An excellent magazine at the time. They had a section for letters to the editor. A reader, in all seriousness, wrote explaining why the US commercial aviation industry was so far ahead of the Europeans. Lockheed and Boeing dominated and there was no Airbus. The reason that he gave was the greater accuracy and finer tolerances used by those companies. The US industry measured components using thousandths of an inch. The Europeans only had millimetres.
A fine example of 'ignorance is bliss'!
 
Is it not illegal to advertise products in imperial units? I know a ban cause much grief in the construction industry in the 70s. At one point sale of foot and inch tapes and rules were banned. Metrication was forced on a largely unsympathetic public who were at home with the old system.
I was teaching Auto. Eng. in TAFE WA @ that time. On decree we immediately taught & changed to the SI metric system.
Imperial & other metric units were not allowed or referenced.
All imperial measuring tools disappeared & as mentioned tapes etc. were all metric 'only'.
Gradually the 7 basic units [below] have been eroded away primarily because the Chinese manufacturers of nearly everything wanting to market in the US & EU rather than have special products for different regions.
 
Early decree following was a government thing.

I was the poor sucker running a design office. Conversion was a nightmare, and very expensive in design and drafting time. Every desk and board (no CAD everywhere then) had extensive conversion tables pinned on. Most things didn't change, fortunately, but everything now needed to be described in millimetres. (For example, a brick course is 3 inches high plus a joint, round about 3/8", the length of a brick still is 9 inches. Do you ever think about sizing brick walls? A rod chart is attached for the curious)

Many things, like piping just adopted nominal metric bores (to this day the world uses BSP inch sizes) and carried on. Timber sections just got described in nominal 50mm increments - no real change there either, they were always nominal off saw. Standard door openings became a nominal 2100x900 to suit standard 2040x820 doors.

One disastrous exception was that some SI enthusiast persuaded Australia to go to 1200x600 ceiling grids, which prevented the butting of troffer light fittings (because the world uses 4 ft tubes, - 1219mm) They also forced sheet materials to become 2400x1200.

Structural design had to use a host of odd units - does anybody have a feeling for a kiloPascal? More conversion tables. Steel sections didn't change then. Concrete now was to be worked out in mm, using the same calculation principles adapted to the new dimensions. Machine computing wasn't normal then as it is now, as few could program or afford the machines. Engineering packages for everyday use were in the future.

So you can see why there were look-up tables pinned everywhere. Conversion slowed us down, and was resisted in most non-government places during the changeover period until it became compulsory to use SI for all clients. Then we had to grin and bear it.
 

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They also forced sheet materials to become 2400x1200.
Most full sheet material I have bought (in both timber and metal) has been (and often still is) 2440 x 1220?
Which is near enough 8' x 4'.
Just type "2440 × 1220 Australia" into Google and take your pick..
 
Much of that stuff (plastics, formed metals, many veneered boards, etc) is imported, and so doesn't follow the 1970's Australian SI decrees.

Since those days manufacturing locally has diminished more than a little.

Nowhere else except the UK got keen on SI purity, and they didn't go as far as we did. The ban on imperial measuring equipment has also been repealed, so you can now buy foot and inch tapes.

Notice that four Australian plasterboard sheets go up to the 2400 ceiling frame.
 
Last night I evened up my tyre pressures to 38 PSI. 😀
I'm pretty good with metric, but tyre pressure, nah
That's interesting. I thought I was the only one with that problem. Worked in the industrial gases industry for years and was (and still) quite at home with metric pressure units, but I can still only think of tyre pressure in psi. Similarly, miles per gallon for fuel efficiency.
Judging by what you see written on various things these days, most people seem to not understand the abbreviations for order of magnitude. You regularly see a small container labelled as containing say, 100ML. Megalitres! Not mL. Area is often quoted in SQMTRS.
 
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Yep. 35 psi in my tyres makes more sense to me than 2.4 bars. Who needs 240 kilopascals? Like the kilonewton, who can imagine it? 36 is a nicer number, being a multiple of 12, so that's better still.

It's not SI, but centimetres have taken off everywhere. Decimetres are only needed when we have to translate PSA manuals into plain English (I mean psi naturally). My foot long torque wrenches measure ft.lb force and I am not going to chuck them out.
 
Early decree following was a government thing.

I was the poor sucker running a design office. Conversion was a nightmare, and very expensive in design and drafting time. Every desk and board (no CAD everywhere then) had extensive conversion tables pinned on. Most things didn't change, fortunately, but everything now needed to be described in millimetres. (For example, a brick course is 3 inches high plus a joint, round about 3/8", the length of a brick still is 9 inches. Do you ever think about sizing brick walls? A rod chart is attached for the curious)

Many things, like piping just adopted nominal metric bores (to this day the world uses BSP inch sizes) and carried on. Timber sections just got described in nominal 50mm increments - no real change there either, they were always nominal off saw. Standard door openings became a nominal 2100x900 to suit standard 2040x820 doors.

One disastrous exception was that some SI enthusiast persuaded Australia to go to 1200x600 ceiling grids, which prevented the butting of troffer light fittings (because the world uses 4 ft tubes, - 1219mm) They also forced sheet materials to become 2400x1200.

Structural design had to use a host of odd units - does anybody have a feeling for a kiloPascal? More conversion tables. Steel sections didn't change then. Concrete now was to be worked out in mm, using the same calculation principles adapted to the new dimensions. Machine computing wasn't normal then as it is now, as few could program or afford the machines. Engineering packages for everyday use were in the future.

So you can see why there were look-up tables pinned everywhere. Conversion slowed us down, and was resisted in most non-government places during the changeover period until it became compulsory to use SI for all clients. Then we had to grin and bear it.
I've still got the booklet sent to every address in Oz, though I'll always go for my 'thou' feeler gauges to confirm my points open 16 thou, and (lower case) psi tyre pressures.

@Fordman
In addition to the si orders of magnitude, the general rule is that abbreviation for a unit is not capitalized unless the name of the unit is someone’s name.
E.g.
feet - ft
pounds per square inch - psi
Newtons - N
Pascals - Pa

page.jpg


pagex.jpg


cover.jpg
 
I remember that book. But that was the simple propaganda for the non-technical masses.

All the technical groups and institutes issued many booklets and sheets, that you guessed, got taped to desks or hung on strings for easy access.

Can you imagine the politicians doing this SI thing if they had to know and deal with the difference between Newtons (force) and kilograms? (1 N is the applied force which gives a mass of 1 kg acceleration of 1 m/s/s). Do they even know the approx acceleration of a mass due to gravity? I've met school kids today who can't handle per second per second.

What I remember is that the proponents were fanatics, and the bulk of people couldn't see much point, but concurred because they were told it was good and had a vague idea that was just multiples of ten, so no big deal, after all they had got used to decimal currency. They hadn't heard of moles and obscure units, and still haven't. Most still think a kg is just a weight. The vast number of practical non-conformities (like bricks) never came to mind.
 
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