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aostling
04-17-2008, 08:35 PM
Personally, I'm happy with feet and inches. Apparently NASA feels that way too, as does the whole of the American aerospace industry. And when I get on a scale I want to see my weight in pounds (or stones if I'm in the UK).

I just missed out on pounds, shilling, and pence -- when I moved to New Zealand in 1971 the country had been on dollars and cents for four years. Any of you oldtimers remember joeys? I have a suspicion that the old coinage was conducive to mental dexterity, not a bad thing.

In metric countries, is there any remaining nostalgia for the old units?

torker
04-17-2008, 08:45 PM
I wish the US would. Then maybe we could get over our half arsed metric adaptation. I realize we'd all have to make some major changes but it is a good system to work with.
We only use metric for some things up here. The rest is the old way. I say either do it or no. All it does up here is confuse kids when they come from a metric schooling background and get plunked into the middle of an old Imperial jobsite.
Any fab place I work at.. any buildings etc. are all Imperial.
However.. I did work for some Germans for 2 1/2 years building a large guest ranch.
They would give me all the measurements in metric. At first I fought it and converted everything. Once I bit the bullet and changed over I really liked the metric system.
Of course.. this was carpentry so it was fractions VS metric. Other than dealing with Imperial sized material it was metric hands down as the easy system to work with.
Russ

John Stevenson
04-17-2008, 08:50 PM
You need to drop the silly 110 volt first and learn what ring mains are.
Then we might let you use a metric rule :D :D

.

dp
04-17-2008, 08:56 PM
I don't think we can afford to reverse ghg's and go metric in the same generation. I think we should wait until I'm long gone.

Doc Nickel
04-17-2008, 09:16 PM
[Grandpa Simpson]

My car gets forty rods to the hogshead and that's just the ways I likes it!

[GS]

x39
04-17-2008, 09:20 PM
I think the metric world should go Imperial.

oldtiffie
04-17-2008, 09:29 PM
Sorry to have to tell you again fellas - but the USA IS metric and has been by act of Congress.


In the Omnibus Trade and Competitiveness Act of 1988, the United States government designated the metric system of measurement as "the preferred system of weights and measures for U.S. trade and commerce". The legislation states that the Federal Government has a responsibility to assist industry, especially small business, as it voluntarily converts to the metric system of measurement. This process of legislation and conversion is known as metrication, and in the U.S. is most evident in labeling requirements on food products, where SI units are almost always presented alongside customary units.

http://en.wikipedia.org/wiki/United_States_customary_units


International inch
In 1959 the United States and countries of the Commonwealth of Nations defined the length of the international yard to be exactly 0.9144 meters[1]. Consequently, the international inch is defined to be exactly 25.4 millimeters.


The international standard symbol for inch is in (see ISO 31-1, Annex A). In some cases, the inch is denoted by a double prime, which is often approximated by double quotes, and the foot by a prime, which is often approximated by an apostrophe. For example, 6 feet 4 inches is denoted as 6′4″ (or approximated as 6'4").

http://en.wikipedia.org/wiki/Inch


The pound or pound-mass (abbreviation: lb, or sometimes in the United States: #) is a unit of mass used in the imperial, United States customary and other systems of measurement. A number of different definitions have been used, the most common today being the international avoirdupois pound of exactly 0.45359237 kilograms.

The word pound comes from the Latin word pendere, meaning "to weigh". The Latin word libra means "scales, balances" and it also describes a Roman unit of mass similar to a pound. This is the origin of the abbreviation "lb" for the pound.

http://en.wikipedia.org/wiki/Pound_%28mass%29

The dollar is metrication in any form as are the units of link (= 66 foot/100 foot - ie 1/100 chain = 66 foot/100 = (66 x 0.3048 meter/100 = 20.1168/100 meter = 201.1168mm) in survey works as well as using decimals in calculations etc. Did I mention all those "thous" and "tenths" of an inch that we all use but that the "inch" itself is 25.4mm?

Do you have "fractional" key-boards? No? Why's that?

So, the USA IS metricated and I suppose you could say that those that are using "imperial" (ie inch, foot, pound, ton - and their derivatives) are actually using units that are multiples or sub-multiples of the metric system.

I, and I expect most others from other than the US, have been through the metrication of our systems and it works fine. Sure there were, and to some extent still are "legacy issues" but they are "fading out". Most of us outside the US are quite comfortable and "bi-lingual" as regards working in or switching between "Imperial" and "Metric".

And to quote the "Bible" (aka "Machinery's Handbook") recent editions, just have a look inside the front and back covers and all you will see are "Conversion Factors".

It is a great and rational system once you get into and used to it.

Perhaps the USA is the only one "marching in step".

Perhaps not.

Optics Curmudgeon
04-17-2008, 09:46 PM
NASA is metric now, and has been for more than a decade. Lockheed Martin found that out the hard way, when their use of imperial measure clashed with NASA's use of metric and the Mars Climate Orbiter went on an unexpected, but programmed (and fatal), detour in 1999. Most who deal with the government in the sciences become unit bilingual very quickly.

Joe

wierdscience
04-17-2008, 09:58 PM
Since I am fluent in both inch and metric I could care less,I will say that a machinist should be proficent in both.

Now with that out of the way,I hate the metric screw thread selection,it sucks period and nothing will change that.Added to that short coming is the fact that there is no international,standard
for the metirc fine series of pitches,that in istelf makes the metric thread selection inferior.You folks in the metric world should have
been able to sort this out in the past 60 odd years you have been arguing it out,but noooooo.:D I'll stick to my sae fastners and my UNC,UNF world standard thread selections thank you very much.

Frankly I don't care which system I use.There should be a law though that which ever system is used whole units must be used under penalty of death.

Recent drawing called out for a .271" holes diameter,WTF?.250" isn't good enough?What about 8mm? Will the machine explode or otherwise mame and kill if the hole size was more or less than .271"?There is no concieveable reason for using the odd size than shear metal masturbation on the part of the engineer who drew it.

Another drawing(cad)had half of the dems in inches and the other half in metric which is a flagrant example of rabid a--holeism.I told the knucklehead who drew it that I converted the inches to mm and the mm to inches as not to foster confusion:D

wierdscience
04-17-2008, 10:04 PM
You need to drop the silly 110 volt first and learn what ring mains are.
Then we might let you use a metric rule :D :D

.

John,the USA gave the world AC power.Great Britan gave the world Lucas,I rest my case:p :D

J Tiers
04-17-2008, 10:05 PM
Sorry to have to tell you again fellas - but the USA IS metric and has been by act of Congress.


Yep, and it goes WAY back..... I understand that in around 1875, the metric system was officially made legal in the USA for interstate trade, by act of Congress.

THAT DATE is the actual date of "metrification" in the US, and it is now over a century ago. It stemmed from a treaty.

http://www.yale.edu/ynhti/curriculum/units/1989/6/89.06.02.x.html

"Although it was official, the real acceptance was gradual. The acceptance of the system in other European countries has taken even longer. A conference in France in 1870 attended by 15 nations including the United States, led to the signing in 1875 of the “Metric Convention”, a treaty under which an International Bureau of Weights and Measures was established. The bureau resides in suburban Paris and is still the world center of metrology. "



I work in a consulting design company now. One of our clients is "going metric'...... They wanted all drawings in metric units. So we did that.

We got a bunch of calls from their proto shop........... I went over there.

NO metric size drills, NO metric taps, No metric measuring tools, not even machinist's scales.

Small disconnect between the "puzzle palace" and the workers...... we went back to decimal inches and everyone was happy.

After all, decimal inches measure is just as rational as any other decimal unit...... just different by a factor of 2.54.

Rookie machinist
04-17-2008, 10:08 PM
You need to drop the silly 110 volt first and learn what ring mains are.
Then we might let you use a metric rule :D :D

.
WOW Just looked that up thats some crazy wiring. Guys here have a hard enough time installing things right, that would surly screw people up.

bob ward
04-17-2008, 10:20 PM
Rather than 'should the US go metric', probably the question that should be asked is thus:-

Given the overwhelming superiority and inherent logic of the imperial system of measurement, should the US go the whole hog and adopt a pounds shillings and pence currency system?

oldtiffie
04-17-2008, 10:29 PM
After all, decimal inches measure is just as rational as any other decimal unit...... just different by a factor of 2.54.

Thanks JT.

That is an excellent comment.

Provided that decimals are used, the "one step" conversions can and do work very well. We use it here in OZ a lot.

The problems really arise where fractions are used as there is a lot more "steps" and room for error.

The method you suggest is exactly what is used in currency conversions and the like.

Working in "whole numbers" and decimal is the best way to go when needed.

I would think that I'd get less "anti-metric" comment if I were to suggest "decimalising" instead - as that has been in effect for a long time and people are using it every day.

There is a common problem in both systems. Non-decimal degree!! Everything is worked out in decimal degree and has to be converted to deg/min/sec to use it on most machines. A real PITA and a classic example of how easy it is to get lost in the conversion process.

There are few - usually rotary tables - that have decimal degree on them.

Vernier protractors are calibrated in deg/min but digital protractors are calibrated in decimal degree but can "do the conversion" to d.m.s electronically if required.

tattoomike68
04-17-2008, 11:37 PM
We have had metric in our medical industry for years. I have seen many metric bearings so I have been machining metric for a long time. it dont mean a thing, just another number is all..

Fasttrack
04-17-2008, 11:45 PM
LOL Doc - great quote!

I'm a physics major and I love metric for just about everything. I think in newtons, not lbs. BUT, the metric screw thread is goofy as hell. I can't imagine willingly changing to the metric screw thread system. I definitely agree with Wierdscience!

oldtiffie
04-18-2008, 12:00 AM
Rather than 'should the US go metric', probably the question that should be asked is thus:-

Given the overwhelming superiority and inherent logic of the imperial system of measurement, should the US go the whole hog and adopt a pounds shillings and pence currency system?

Wow, Bob

It just hit me what you said.

But I think they are having problems with the currency of LSD as it is.

Evan
04-18-2008, 12:30 AM
If you are working in CNC programming a funny thing happens. There isn't any imperial or metric. You just use "units". It isn't until run time that you need to decide how big the units are compared to your work piece. Then it's just a matter of scale. If the scale is wrong then you set the scale to make it right. For instance, in CamBam you have 5 different scales you may work in. Inches, millimeters, meters, centimeters or thousandths. You can switch anytime and all that happens is the scale changes. The numbers stay the same.

BTW, the old standard of 1/2", 1/4", 1/8, 1/16 etc isn't purely fractional. It's binary. If it were fractional then you would also have the non-binary divisions such as 1/3, 1/5, 1/7 etc. Binary is nice because it's all powers of two.

I've been using metric since I was a child growing up in California. Metric has been the system of choice in science since the system was adopted. As my father was heavily involved in scientific pursuits and as a science teacher he made sure that I learned to use metric.

There isn't anything difficult about it. Everybody here knows how to count to ten, I presume.

It also has the major advantage of commonality of units. 1 cubic centimeter of water weighs one gram and equals a volume of 1 millilitre. So, a liter weighs a kilogram and a cubic meter weighs a tonne which is 1000 liters of water. Tell me, without using a calculator, how many cubic inches are in a cubic yard? There are 1,000,000 cubic centimetres in a cubic meter.

torker
04-18-2008, 12:36 AM
Ooops.. I forgot how much I hate metric bolts/screws. I deal with them everyday in my motorcycle yard. Metric screws and aluminum are a poor mix IMO.
I ran a highly stressed 572 ci all aluminum blown alky motor for years and never had the problems (with the SAE fasteners) that I have in the bikes/quads.
But for carpentry and fab work metric would be a blessing.

juergenwt
04-18-2008, 12:44 AM
Amen to that.

wirewrkr
04-18-2008, 01:03 AM
So, at the risk of swimming against the current, (which I'll do anyway)
what exactly do you guys have against metric threads in your hardware?
I was taught fractions as a kid in my dads woodshop, learned metric as a ten year old when I started building bicycles, graduated to german cars and motorcycles later and Prefer metric hardware to all others, Yes, even over
Whitworth(less).
I hate 1/4 20 bolts and screws. Give me a 6x1.0 any time.
Robert

juergenwt
04-18-2008, 01:15 AM
Remember the scene from Titanic:"It may take some time - but down she will go"
Same with US customary system (It is not imperial). It should have ended with
the Model "T". Come on now, would you like to have eight dimes to a Dollar and 16 Nickels and 32 pennies? The people talking about metric threads being complicated should take a look in a machinist handbook.
Next time you are adding up dim's for 2x4 and 2x2 and 4x8 and feet and inches and fractions on your home project let me know why you made a mistake. For the metal workers who have to add things like 1 1/2 + 3/4 +
+5/8 + 3/32 easy - WE MADE IT METRIC. (1.5+.750+.625+.0935). As for driving - look at your odometer - 22.5 miles not 22 1/2 mile. The rest of you who like to have a brew after work like me -ask your bartender how many 12oz glasses he can get from a 1/2 barrel. DO IT! Makes you wonder how they know how much to charge.

kendall
04-18-2008, 01:39 AM
I don't know. I've never seen anything wrong with imperiel measurements. Both make sense, but to me the imperial makes more sense.
Half of either is still (point)500. I'm comfortable with metrics (owned honda bikes for 35+ years)

I'm a carpenter, and the only time I realy prefer using metrics is when I'm building stairways simply because the rise/run calcs end up in tenths anyway, so if you start with base 10 measurements it all comes out easy.

Major advantage of metrics is that it's easier and doesn't require as much mental effort to use

If you realy come down to it, there is no reason that a meter is better than a yard, or a centimeter is better than an inch other than the fact that it takes less mental effort to divide.

The only advantage in manufacture is if you use material supplied in the unit you use, metric for metric, inch for inch. Using metric based stock to produce inch based product can result in more waste.

If computers etc weren't binary based there would be no advantage at all to metrics.

Ken.

jimmstruk
04-18-2008, 01:46 AM
Back in the 60s they said we would change to metric I screamed NO WAY. I would never buy a metric tool or any other piece of metric junk. Progress? finally got the best of me. I bought a couple of metric sockets, then one more, the a wrench etc. Now all I lack in metric tools is micrometers. We should have changed 100% years ago in my opinion. Evan is right, most everyone can count to 10. JIM

jimmstruk
04-18-2008, 01:56 AM
By the way I forgot to mention, Harbor Freight had digital calipers for $10. One push of a button and instant conversion - metric to imperial or the other way. I just used the caliper to make a measurement for a metric allen wrench. Now I own a 17mm allen wrench. JIM

dp
04-18-2008, 02:08 AM
I think the issue of metric vs not metric comes down to a simple fact of life: Their 1 is different from our 1.

1 yard vs 1 meter - what is that all about? Fix that, we have no problem.

It just gets worse from there. We have 1 inch. They have tens of centimeters. What a waste. Surely there are carbon credits found in some of that excess. I fold a sheet of paper twice and I've quartered it. I cannot find a clever way to fold a sheet of paper that produces 10 sections. No matter how I try there are 12 biscuits in a dozen and that's how many pockets there are in my biscuit pan. I don't want a metric dozen, I want twelve biscuits. That makes 8 for me and 4 for the missus. In gravy with sausage that's an even number no matter how you cut it. It does not surprise me one little bit that there are 5 pockets in my aebleskivver pan - clear sign of metric fiddling going on there.

10 is unnatural except for counting toes and fingers. Once you start to make stuff, multiples of two become important, and while 10 is a multiple of two, it is the least used multiple of two of all the multiples.

I really do not want to try to buy 49X98's to frame a shed - I want 2x4's. And I sure don't want to see our healthy forests converted to withering metric sticks. And a 10d nail should by gawd be a 10d nail. I don't ever want to find a Euronail in my nail bucket. What the hell does a Euronail weigh by the gallon, anyway?

And I am especially offended that printing paper is sized such that the length of one side is the square root of 2 times the other. Paper should be 8.5x11". It was like that when I was a kid and it still works today.

And I would just warn the reader not to take any of this too seriously - there's a reason things are as they are that have nothing to do with science! :)

boslab
04-18-2008, 02:17 AM
WOW Just looked that up thats some crazy wiring. Guys here have a hard enough time installing things right, that would surly screw people up.
never mind the voltage they keep changing the colours over here, red blue yellow [3ph]=brown blue gray [3ph] dont ask abot 1ph
and timber 2X4=4X2=100X50[mm]/m[long]
how do you spell libra cicterci dinario et al
horses in metric hands[4"]=100mm=1 decimeter, i think they are shrinking, cant find the 3/8"drill will 10 mm do
mark

oldtiffie
04-18-2008, 02:54 AM
If computers etc weren't binary based there would be no advantage at all to metrics.

Hi Ken.

I wasn't going to mention this but my "log books" with my logarithms, trig. functions etc. etc. were all decimal quantities even though the columns were in degree and second - the columns on the right were in arc minutes.

My slide rules were all decimal - to the bases 10 and/or "pi".

Odometers dials in cars were raised by powers of 10 and the small quick dial was in 1/10 mile.

Paper sizes in small pads and larger drawing office sizes were completely irrational - both UK and USA. Metric is dead easy.

So, irrespective of whether Metric or not the decimal version of the USA/"Imperial" system is easier for me to use than fractions - hands down.

We can still buy steel/metals in "inch" as well as metric - plate, sheet, sections, nuts, bolts, washers etc. so we have it both ways.

MS "Word" still works in "point" which are 1/72" - a very old traditional Printers measure that despite the "preferred numbers" in both metric and imperial systems and so has not, and quite likely will not change.

1/4", 3/8", 1/2" etc. socket set drives are "hard converted" in metric to stay the same "as was" in Imperial/inch. They are specified in mm to be exactly the same as they were/are in inch.

TECHSHOP
04-18-2008, 03:20 AM
What really bothers me is the "Chinafication" of the two systems, I am finding more and more "crossbreeded" items:

1/4-20 machine screws with a M4 "Allen" hex
3/8-16 hex head cap screws marked "SAE grade 8.8" and needed a 16mm socket to drive.

What madness...

Peter N
04-18-2008, 04:16 AM
Added to that short coming is the fact that there is no international,standard
for the metirc fine series of pitches,that in istelf makes the metric thread selection inferior.You folks in the metric world should have
been able to sort this out in the past 60 odd years you have been arguing it out,but noooooo.:D


I'm afraid that this old myth comes up time and time again.
There has been a standard for metric fine for many years, and it takes the work of a few seconds to google for it:

http://www.newmantools.com/tech/threadmf.htm
http://www.tribology-abc.com/calculators/metric-fine-iso.htm
http://www.gewinde-normen.de/en/iso-fine-thread.html

Having said that, metric coarse is the preffered norm for most applications, and I have only come across metric fine a handful of times in the past 30-odd years, alloy engine cases on japanese motorcycles being one.

I too am happy to work in both, but on balance prefer metric.

Peter

John Stevenson
04-18-2008, 04:21 AM
John,the USA gave the world AC power.Great Britain gave the world Lucas,I rest my case:p :D

Then things moved on.
The world adopted AC power and standardised on 240 v single and 440 volt three phase and we sold Lucas to you.

So you now still have 110 volt 60 cycles AND Lucas.

With these qualifications you aren't ready for metric yet :p :D

.

Swarf&Sparks
04-18-2008, 05:19 AM
Born in Smiljan, Croatia , Austro Hungarian Empire, he was an ethnic Serb subject of the Austrian Empire and later became an American citizen.

The subject? Nikola Tesla.

Anyway, if you must rationalize feet and inches, why not have a decimal foot of ten inches? Then milli-inches, etc :D

Asquith
04-18-2008, 05:55 AM
I have no problems working with both systems.

I was with a German recently, and he told me that they still buy things like bread by the 'pound' (pfund, 1/2 kg), and one common word for ruler translates as 'inch stick'!

Evan
04-18-2008, 06:56 AM
Heh. I used to find it handy to use a metric ruler when drawing things on paper. 1 cm = 1 foot :D

Too_Many_Tools
04-18-2008, 06:56 AM
I wish the US would. Then maybe we could get over our half arsed metric adaptation. I realize we'd all have to make some major changes but it is a good system to work with.
We only use metric for some things up here. The rest is the old way. I say either do it or no. All it does up here is confuse kids when they come from a metric schooling background and get plunked into the middle of an old Imperial jobsite.
Any fab place I work at.. any buildings etc. are all Imperial.
However.. I did work for some Germans for 2 1/2 years building a large guest ranch.
They would give me all the measurements in metric. At first I fought it and converted everything. Once I bit the bullet and changed over I really liked the metric system.
Of course.. this was carpentry so it was fractions VS metric. Other than dealing with Imperial sized material it was metric hands down as the easy system to work with.
Russ

The United States already has gone metric.

They had China do it for them.

TMT

John Stevenson
04-18-2008, 07:08 AM
The United States already has gone metric.

They had China do it for them.

TMT

LOL, never a truer word spoken.

Next step is the ratification of CSW, Cantonese Standard Whitworth.

JCHannum
04-18-2008, 07:13 AM
The chief advantage of the Imperial system is that it is natural. If you were stranded on a desert island, and had to create a crude measurement system using only materials at hand it would more closely resemble the Imperial system than the metric, and it would be fractional, not to the base ten.

Swarf&Sparks
04-18-2008, 07:19 AM
So, naturally, I'd start making a micrometer from palm fibre and resin? :rolleyes:

oldtiffie
04-18-2008, 07:21 AM
Originally Posted by Too_Many_Tools
The United States already has gone metric.

They had China do it for them.

TMT

LOL, never a truer word spoken.

Next step is the ratification of CSW, Cantonese Standard Whitworth.

Agree John.

230/240V 1ph 50Hz power supply here on ring mains.

And I will be very pleased to watch some of the Mandarins here learning Cantonese.

Chop-chop.

Swarf&Sparks
04-18-2008, 07:24 AM
Or maybe some in this cantonment will learn Mandarin :D

oldtiffie
04-18-2008, 08:00 AM
The chief advantage of the Imperial system is that it is natural. If you were stranded on a desert island, and had to create a crude measurement system using only materials at hand it would more closely resemble the Imperial system than the metric, and it would be fractional, not to the base ten.


So, naturally, I'd start making a micrometer from palm fibre and resin? :rolleyes:

Not quite Lin.

As Jim Hannum (almost) said, only those on a desert island (continental North America??) will be using foot and itches - they'll be starting from scratch.

Ten fingers and ten toes and not to base ten??

Its starting to look like a strip from the "Hager the Horrible" comics (not rubbishing Jim H - at all) where Hagar and Lucky Eddie are marooned on a desert island.

Swarf&Sparks
04-18-2008, 08:04 AM
Ah well, I'll just have to do as the bowmen at Agincourt and stick with binary.

Gimme two fingers.
(of whisky , of course :D)

J Tiers
04-18-2008, 08:25 AM
240V isn't your standard anyway..........

it's now 230V, "harmonized".

The US has "240V" all over. Got it in the house, there is a lot of 240V 3phase, etc, etc.

The ring main and the fuse in the plug, where the plug is as big as an old electric shaver...... no thanks. I prefer the French version of the Schuko plug, the one with the decent ground.

As far as 50 Hz, that is simply inefficient. Every bit of equipment must be bigger proportioned at 6/5 the size, with that much more iron in the core, or that much thinner copper and more turns......

If smaller, it must be less efficient, and/or be made for a lower duty cycle, etc. Don't talk to me about IEC contactors..... aka "toasters".

Power should be distributed at the new metric frequency of 100 Hz.

Voltage should be 100V.

Swarf&Sparks
04-18-2008, 08:27 AM
Harh, transformers are much more efficient at 5Khz :D

oldtiffie
04-18-2008, 08:28 AM
Born in Smiljan, Croatia , Austro Hungarian Empire, he was an ethnic Serb subject of the Austrian Empire and later became an American citizen.

The subject? Nikola Tesla.

Anyway, if you must rationalize feet and inches, why not have a decimal foot of ten inches? Then milli-inches, etc :D

Great idea Lin.

They can catch centipedes (foot) and millipedes (metric) use them as an abacus to suit.
http://en.wikipedia.org/wiki/Centipede
http://en.wikipedia.org/wiki/Millipede
http://en.wikipedia.org/wiki/Abacus

Should be any amount of "Petrel":
http://en.wikipedia.org/wiki/Petrel

But watch out for the raw material for guano:
http://en.wikipedia.org/wiki/Guano

Swarf&Sparks
04-18-2008, 08:31 AM
Brilliant Mick!
use a centipede and a millipede on the Vernier principle :D

JCHannum
04-18-2008, 09:14 AM
Sorry Tiff, that is not what I said. The Imperial system used natural, familiar objects as a base, and division by simple folding to subdivide. Both methods easily done with materials at hand.

The meter was originally artificially contrived and defined. The original survey to define it as related to a function of the length of the earth's quadrant passing through Paris (real science there) was found to be wrong. It has been jerked around since to relate it now somehow to some wavelength of something or another that cannot really be proved or disproved, and which has no relation to anything in the real world.

It seems that the so highly vaunted Metric system is based on a mistake.

Swarf&Sparks
04-18-2008, 09:20 AM
not gonna start the spelling police thing here (again)
but a meter is a measuring instrument, a metre is a measure

oldtiffie
04-18-2008, 09:32 AM
Sorry Tiff, that is not what I said. The Imperial system used natural, familiar objects as a base, and division by simple folding to subdivide. Both methods easily done with materials at hand.

The meter was originally artificially contrived and defined. The original survey to define it as related to a function of the length of the earth's quadrant passing through Paris (real science there) was found to be wrong. It has been jerked around since to relate it now somehow to some wavelength of something or another that cannot really be proved or disproved, and which has no relation to anything in the real world.

It seems that the so highly vaunted Metric system is based on a mistake.

Maybe so Jim. Maybe no.

The wavelength is a "known", but irrespective of that the inch is now defined as a function of the meter - like it or not.

The "folding/halving" - 1/2, 1/4, 1/8, 1/16, 1/32, 1/64 etc are all OK in the "inch" context but fall apart in the foot (12 inch), yard (3 foot), chain (22 yard) and mile (80 chain) etc.

In that context too, the "weights" (Brit/UK and European) systems were a complete disaster.

Adding and subtraction were a PITA but multiplication and division were a nightmare - the more so if fractions were involved.

Non-decimal coinage - forget it!! Ask any who had to deal in half-penny, penny, three-penny, six-penny, shilling, guinea, pound, florin etc.

And don't even mention time and calendars!!

I could not even contemplate using other that a decimal based system for day-to-day use - either in inch or metric.

Evan
04-18-2008, 09:35 AM
I tend to spell it both ways, sometimes in the same sentence. I get caught between European spellings and US spellings all the time.


It seems that the so highly vaunted Metric system is based on a mistake.

That's a strange thing to say. All measurement systems are based on purely arbitrary units of measure regardless of what they are called.

oldtiffie
04-18-2008, 09:42 AM
not gonna start the spelling police thing here (again)
but a meter is a measuring instrument, a metre is a measure

Thanks Lin.

Point well made and taken.

Note to self: slap wrist.

Oops - no can do - limp wrists.

John Stevenson
04-18-2008, 10:05 AM
The ring main and the fuse in the plug, where the plug is as big as an old electric shaver...... no thanks. I prefer the French version of the Schuko plug, the one with the decent ground.
Or the famous American invention, magic smoke :D


As far as 50 Hz, that is simply inefficient. Every bit of equipment must be bigger proportioned at 6/5 the size, with that much more iron in the core, or that much thinner copper and more turns......
That inefficient that 9/10 of the world uses it ?
and that bigger that the smaller blue motor here is 1/2 as big again in power and has a better efficiency rating than the American gray motor ?

http://www.stevenson-engineers.co.uk/files/bridgy_motor1.jpg






Power should be distributed at the new metric frequency of 100 Hz.

Voltage should be 100V.
Cables should be 2 sq in to carry this load :D sod the price of copper, bring on more magic smoke.

.

bighammer
04-18-2008, 11:01 AM
Metric based on a mistake??? I dunno, but it is used by some real idiots.I have a jet lathe with 6mm screws, .1, .08, and .075 thread pitch all on same machine. Find me a source of supply for the oddball .08 thread pitch and even the supposedly standard fine thread of .075. I have posted a sign in the shop "work requiring metric fasteners $25 surcharge, work requiring special thread pitch metric fasteners be made $100 plus all parts and labor."

wirewrkr
04-18-2008, 11:17 AM
I have a jet lathe with 6mm screws, .1, .08, and .075 thread pitch all on same machine. Find me a source of supply for the oddball .08 thread pitch and even the supposedly standard fine thread of .075. I have posted a sign in the shop "work requiring metric fasteners $25 surcharge, work requiring special thread pitch metric fasteners be made $100 plus all parts and labor."

Oh yeah, no one mentioned That the Chinese have their own metric system.+
Robert

jkilroy
04-18-2008, 01:47 PM
The metric system, as it pertains to fasteners, is so screwed up, with way more diameter/pitch combinations than ever existed in the "old" system that it is laughable. Lets not even get started with pipe fittings! There have to be at least 10 different thread models for plumbing that are metric based. Its a serious mess, and one that I am not using, all of my products are based on imperial measurement and I have never had a "metric" customer complain about it yet.

juergenwt
04-18-2008, 02:30 PM
Techshop - I found the same thing and here is my thought on this: Mostly you will find things like 1/4-20 screws with a metric hex-head or a metric socket head. The same thing happens on other screw sizes.
Now when you look at the product you will find that all are US-designed with the US name. Things like "Chicago Tool" , "Black and Decker" etc. etc.. What happened is that the US company sent the design specs to China to have the tool made. So they made them with 1/4-20 or so screws but had no inch hex stock available and used the next metric material size in their screw machines.
Ps.: Did anybody find a bartender who knew how many 12oz glasses from a 1/2 barrel of beer?

SDL
04-18-2008, 02:59 PM
The metric system, as it pertains to fasteners, is so screwed up, with way more diameter/pitch combinations than ever existed in the "old" system that it is laughable. T.

This is the view from looking at one country’s system and comparing with all threads from lots of other countries. I have designed all sorts of industrial products with metric for 30 years and only used metric coarse for fasteners.

When it come to special mating parts then there is a preferred range of ISO diameter and pitch combinations. But is no different to just picking a TPI that suits.

From my visits to work in the states Metric is no problem, not as our distributor used to make out and get me to post 4 off M8 screws and an Allen key. When I saw that they could be got at ACE hardware etc that soon stopped.

Shear force of world market prices will change the standard in the US in the end, look at all the Chinese m/c tools all with metric fasteners. It would be easier if one of the big US std organisations pushed using std metric coarse.

The rest will end up as a cottage industry like those in the UK still designing with BSW and BA fasteners.

Steve Larner

Swarf&Sparks
04-18-2008, 03:34 PM
Agreed, Steve, if the chinese could make metric (or any kind of) fasteners, out of something harder than bakelite.

Maybe the situation's changed since I bought my lathe?

malbenbut
04-18-2008, 03:41 PM
I have a metric hammer and a couple of metric screwdrivers and they are just as easy to use as imperial.
MBB

SDL
04-18-2008, 03:44 PM
Agreed, Steve, if the chinese could make metric (or any kind of) fasteners, out of something harder than bakelite.

Nope

My 6*4 Bandsaw had crap fasteners which I replaced with A4 stainless ones. Bu I know that they came from China, just better Quality.

Still I would rather replace the fasteners than pay 50% more which is how it seems to go in these things.

Nearly all fastners and wood screws in the UK are from china now. I have been to a sister company of where i work in Holland and they still get good quality fasners from Europe, but i dont know the cost premium.

Steve Larner

Swarf&Sparks
04-18-2008, 03:48 PM
Zachary what I did with my Taiwanese lathe Steve.
Selection of M(x) SHCS
Otherwise, it's a damn fine little machine.

John Foster
04-18-2008, 03:53 PM
You can argue forever as to which system is better but for me there are two reasons we should change.

First and most important is that we loose a great number a students in math when they hit fractions. After they give up on fractions all the rest of math (and later science) is lost also. I taught in a tech school for 35 years and one thing you could bet on was that 25 percent (that's 1/4) of tenth grade boys could not read a ruler accurately to 1/16"! When teaching adults (machine shop) I never asked if they could read a ruler (no one wants to admit they couldn't) but instead asked them to set a caliper to 17/32". You got your answer real quick. If they could set it we went to work on the lathe. If not we had a classroom session.

All of the big shots, both at the state level and nationally, are wanting to make school standards higher, tougher, etc. Well good luck teaching calculus when kids have hated math since third grade. You would be hard pressed to find a third grader that does not know 10 cents to a dime and 10 dimes to a dollar (or base 10) but forget fractions.

Second, we are out of step with the rest of the world. Why do all those other people hate us when we know all the answers. If they would just change to our way of doing things, the world would be perfect. And if you don't agree we'll bomb and kill you ignorant heathens until you do. Strong words but not far from the truth.

I really thought that American industry would change and go metric back in the '70's but I sure missed that one. So now we have both systems to contend with (on the same tool or auto) plus the bastard combinations mentioned above.

I read this board all the time but seldom comment because you guys do a great job. I also know I am wasting my time writing this but since both systems have problems it doesn't matter which we use, lets get in step with the rest of the world for a change.

tony ennis
04-18-2008, 03:58 PM
inches by the ten-thousandth works for me.

Swarf&Sparks
04-18-2008, 04:03 PM
John, I know that 17/32 is a shade over 1/2, but damned if I'd like to set that on a vernier!
If I'm old enough to work in 1/32, I'm too old to see the damn thing.
Bring on the digitals, or just let me work with a mic (in either system)

Alistair Hosie
04-18-2008, 04:57 PM
Scotland gave the world whiskey:DAlistair

John Stevenson
04-18-2008, 05:02 PM
Scotland gave the world whiskey:DAlistair

Scotland never gave anything...they over charged for it .........

.

small.planes
04-18-2008, 05:12 PM
Selection of M(x) SHCS

If they are chinese thats has to stand for Shear Head Cap Screws :p

Dave

Swarf&Sparks
04-18-2008, 05:15 PM
No Alistair, Scotland gave the world whisky!

Swarf&Sparks
04-18-2008, 05:16 PM
And, yup, yer right Dave.
That's why they were all replaced with brand-name SHCS.

oldtiffie
04-18-2008, 05:52 PM
And, yup, yer right Dave.
That's why they were all replaced with brand-name SHCS.

That's so Lin - very much so.

(Melbourne, in Australia has a Chinese Lord Mayor - John So - or to quote the Japanese - Ah So).

I have to say that a lot of Chinese stuff does have "weak" fasteners and that it is good idea to at least check and if in doubt - change them to known "name" stuff. Its a small price to pay for what in most - but not all - cases are very serviceable machines and tools. The machines and tools are probably not as "heavy/industrial" as some of the "name" stuff made in US, UK, Europe etc. but I am not "Commercial" in my shop and so the capacity and capability of the Asian stuff meets my needs nicely - mostly.

The "time bomb" or "booby trap" is not so much the fasteners you can see but the possibility of failure of the ones you can't see. But having said that I've never had a "hidden" fastener fail although I know that some on this forum have.

oldtiffie
04-18-2008, 05:57 PM
Scotland gave the world whiskeyAlistair


Scotland never gave anything...they over charged for it .........

.

Being half-charged on some of that that "Single malt" is bad (good??) enough but being over-charged is delightful.

Swarf&Sparks
04-18-2008, 06:00 PM
have to pass on this one though Mick.
on the aforementioned taiwanese lathe.
carriage handwheel locked between 2 points
hmmm, strange
hmm, can't move saddle
hmmmm, BUGGER!

boiled down to one of the chi#$%*&ese SHCS backed out of the rack, inside the apron.

And that's after I thought I'd replaced all the critical fasteners.
Fun getting that bast@rd out. But that's a tale for another day.

bob ward
04-18-2008, 06:27 PM
First and most important is that we loose a great number a students in math when they hit fractions.
I used to loooooove wrestling with fractions, but maybe thats just me.


I really thought that American industry would change and go metric back in the '70's but I sure missed that one.
In a way the major players did. GM Ford, Chrysler and indeed any US company with substantial overseas operations have been doing their designs worldwide in metric for the last 30 odd years. You might still have imperial nuts and bolts on your Chev, (I don't know, do you?) but originally, somewhere they would have been called out as a metric size on a metric drawing. But its taking a long time for that influence to filter down to the consumer level.

I guess a preference for metric or imperial is like religion and race, its all an accident of birth, and yours is the best, no question about it! Did not a presidential hopeful say something recently about some Americans clinging to guns religion and the imperial measurement system?;)

Re the bastard thread/head combinations mentioned earlier, a UK equivalent was found in a Morris engine in the 30s. Morris bought all the tooling and plans for their 8hp engine from Hotchkiss in France and naturally all threads were metric. But the OD of the nuts and bolt heads were changed to Whitworth sizes to suit the English tools of the time.

LES A W HARRIS
04-18-2008, 06:41 PM
Is anyone aware that random sampling of barleycorns, yields three barleycorns equal 0.939" (23.85mm) not 1.000" (25.4mm)? The sky is falling! :confused:

Cheers,

J Tiers
04-18-2008, 06:56 PM
Apparently you are unaware of the fact that the only rational number system is composed of fractions.

The other ones are totally irrational.

Per the motor thing.....

You can get a particular motor to be more efficient than another particular motor.

But..... it is a fact that you must have 6/5 the core material for 50 hz than for 60 Hz.

A large old motor may have too much low quality iron, and be lossy. A new motor for 50 OR 60 Hz is probably more efficient by a good margin. So what's new?

When designed the exact same way, a 60Hz motor will have less iron etc in it than a 50 Hz motor.

Likewise, a 60Hz transformer designed the exact same way as a 50 Hz transformer will have less iron etc in it than the 50Hz version.

It's basic physics, and is totally unavoidable.

In fact, a transformer operated at 50,000 Hz will be very much smaller and a great deal more efficient than a 50 OR 60Hz transformer of the same power capability.

A move to a universal 100Hz power supply would increase efficiency, and decrease material usage by half. A higher frequency would be even better, but may begin to have other problems.

As for voltage, the required spacings for 240Vac are larger, and the 240 is inherently more dangerous.

Magic smoke indeed...... Lucas already has let out all the smoke.

John Stevenson
04-18-2008, 07:18 PM
Magic smoke indeed...... Lucas already has let out all the smoke.

Don't know you'll have to ask them.

One point, today I have been working on a small CNC conversion on a bench I have for this purpose.
To the side of the bench is a 6 way strip adaptor with switched sockets.
The sort that take our big laughable plugs.

In this I have a small soldering iron, a heat gun, a drill, a Dremel and the supply to the machine.
The strip is plugged into the ring main via another big laughable plug with a 13A fuse in, the max we are allowed on 240 volt.

The soldering iron is 2A, the heatgun is 10A, the drill is 5A, the dremel is 3A and the machine is 10A

Now I can add and know that this load is greater than 13A but only two appliances are on at once, like the machine and soldering iron or heatgun and soldering iron so I'm within limits.

If anything goes wrong with any of these appliances it will only take out the plug fuse for that appliance.

In fact I made a mistake today on the original unmarked dual transformer and blew the 10A machine fuse, nothing else was touched.

Using the unfused strips and plugs sold in the US how can you duplicate this setup safely.

I'll be very honest here as it wasn't until I first started reading rec.crafts.metalworking when it was possible to read about metalworking and not politics and guns that I read about magic smoke.

Perhaps I need to burn stuff out more instead of buying fuses in bulk ?

.

wierdscience
04-18-2008, 07:36 PM
Don't know you'll have to ask them.

Using the unfused strips and plugs sold in the US how can you duplicate this setup safely.


.

We have circuit breakers.They can be reset,we also have thermal switches for overloads.The fact that we don't have people dropping like flies from electrocution means it's good enough:D

John Stevenson
04-18-2008, 08:03 PM
So what size circuit breaker would you fit on that strip setup or do you need 6 returns back to the box for seperate trips ?
.
We still have a trip back in the box to protect the ring main. I have three shops as regards power split off's, each one has ring main trips and RCD's

Doing a quick check on Google on deaths by electricution in both the USA and the UK and a compare on population they are very similar 0.7 per million in the US compared to 0.8 in the Uk but we are using double the voltage so the deaths should be far higher.

So either we are more careful or our system is inherently safer.

wierdscience
04-18-2008, 08:23 PM
So what size circuit breaker would you fit on that strip setup or do you need 6 returns back to the box for seperate trips ?
.
We still have a trip back in the box to protect the ring main. I have three shops as regards power split off's, each one has ring main trips and RCD's

Doing a quick check on Google on deaths by electricution in both the USA and the UK and a compare on population they are very similar 0.7 per million in the US compared to 0.8 in the Uk but we are using double the voltage so the deaths should be far higher.

So either we are more careful or our system is inherently safer.

Any voltage to ground trips the breaker,the object being to protect the user and not the appliance.

The slightly higher numbers are probably due to many more overhead powerlines that fall in storms or are ran into by crews running heavy machinery.

mochinist
04-18-2008, 08:27 PM
So what size circuit breaker would you fit on that strip setup or do you need 6 returns back to the box for seperate trips ?
.
We still have a trip back in the box to protect the ring main. I have three shops as regards power split off's, each one has ring main trips and RCD's

Doing a quick check on Google on deaths by electricution in both the USA and the UK and a compare on population they are very similar 0.7 per million in the US compared to 0.8 in the Uk but we are using double the voltage so the deaths should be far higher.

So either we are more careful or our system is inherently safer.I really shouldn't comment as my electrical knowledge is pretty limited, but I had always heard from electricians that they preferred to work with the higher volts because 110 tends to grab you and not let go and the higher voltages will literally blow you away. I cant imagine either is fun.:eek: Honestly I dont know, I have a family member that is an electrician and he works for food and beer so I leave that sh1t to him.



As for metric I wish we would, it doesnt bother me to work in either, but the older guys at work are stubborn and want to convert everything, instead of just hitting the english to metric button on the dro and calipers.

oldtiffie
04-18-2008, 08:51 PM
Fasttrack posted a very good thread recently at:
http://bbs.homeshopmachinist.net/showthread.php?t=28659

Regarding hos repair of his Mitutoyo calipers.

At his post:
http://bbs.homeshopmachinist.net/showpost.php?p=350116&postcount=2

was a pic (one of several) of the calibrated beam and dial:
http://i108.photobucket.com/albums/n22/fasttrack237/100_0149.jpg

I was not going to mention this before but it might make a relevant or salient point or two in this discussion.

First of all, I regard Mitutoyo as "way up there" as regards quality, accuracy, reliability and durability - no question.

But I did notice that the beam (rule?) is calibrated in 1/10" = 0.10" and the dial at 0.010" and 0.001".

Nobody thought it odd that the rule on the calipers is calibrated in "decimal inch" (so is the dial) and yet the rule on the bench or in your pocket is calibrated in "fractional inch". The only way to relate the rule to the caliper and vice-versa is to do a fraction-to-decimal and/or decimal to fraction conversion to use the two tools concurrently.

I used to have steel rules calibrated to 1/10" and 2/100" (1/100" on a depth guage is a PITA to read) and they all worked fine.

I continually notice that "rush", "time-saving", "make lottsa big chips quick" etc. seems to be endemic here (don't see the relevance in a Home or Hobby shop).

Yet each of these fractions to decimal (and reverse) takes (so-called) "valuable time" and is a likely source of error at the best of times.

All of my rules are metric - some with inch on them as well - but I deal in decimal inch when in inch measurement and revert to metric (decimal) with ease.

Just about all - if not all - inch machines are calibrated in decimal inch as well - even fractional inch lead-screws.

Carpenters, Joiners, welders and fabricators all worked (mostly) in 1", 1/2", 1/4", 1/8", 1/16", 1/32", 1/64" and 1/128" so most stuff used the same fractional system (still do) and it did and does work very well.

Engineering, Science and Construction all work in metric here.

Metric dimensioning on drawings works world-wide - even if the notes etc. need translation from "English" (here) to another spoken or written language else-where - and reverse, of course. Sending or getting drawings or dimensions in other than metric is pretty well a "no-no".

Isn't it odd.

wierdscience
04-18-2008, 10:14 PM
It's not odd,it depends on trade.Most machinists scales are in 10ths of an inch,carpenter's rules and structural fitter's rules are in 1/16ths.

Everything in the machineshop is in decimal inches.1/10" is exactly .100"Nothing at all hard about the system,can't understand why Euro's can't seem to grasp the concept since it's so simple.

There are only two units to keep straight whole inches and decimal inches.

1.250" is 1-1/4" no doubt.

Now in metric what is 1.250?

dp
04-18-2008, 10:19 PM
There are only two units to keep straight whole inches and decimal inches.

1.250" is 1-1/4" no doubt.

Now in metric what is 1.250?

30 and 5/8 cm.

oldtiffie
04-18-2008, 10:27 PM
There are only two units to keep straight whole inches and decimal inches.

1.250" is 1-1/4" no doubt.

Now in metric what is 1.250?


30 and 5/8 cm.

Thanks Dennis.

Touché.

loose nut
04-18-2008, 10:32 PM
So what size circuit breaker would you fit on that strip setup or do you need 6 returns back to the box for seperate trips ?
.
We still have a trip back in the box to protect the ring main. I have three shops as regards power split off's, each one has ring main trips and RCD's

Doing a quick check on Google on deaths by electricution in both the USA and the UK and a compare on population they are very similar 0.7 per million in the US compared to 0.8 in the Uk but we are using double the voltage so the deaths should be far higher.

So either we are more careful or our system is inherently safer.

If people would quite licking the power outlets there wouldn't be any deaths from electrocution, it only takes about 35 milliamp to kill you so both electrical systems are equally deadly.

People are make mistakes about the metric system

1- the metric system is a decimal system but not all decimal systems are metric.

2- The imperial system is a fractional system but so is the metric system IE: 1/2 MM etc. but people using the metric system chose not to use fractions, the imperial system is also a decimal system but we chose to use fractions, we don't have to.

3- the American auto makers are basically now metric and they are tanking at an unbelievable rate, coincidence, I think not.

Why can't we just adopt both systems world wide and everyone can mix and match as they chose, enforced standardization hampers creativity..

doctor demo
04-18-2008, 10:41 PM
Thanks Dennis.

Touché.
how do we know it is not 1 1/4 meters:D .
What I am curious about is if you go to a metric bar and order '' a shot '' how much of your favorite beverage will you get?:confused: .
Steve

oldtiffie
04-18-2008, 10:45 PM
Why can't we just adopt both systems world wide and everyone can mix and match as they chose, enforced standardization hampers creativity..

Thanks loose nut - good summary.

Both systems are in use, have been and will be for a long time.

More and more stuff is specified or identified in metric and so "inch" system users have to convert mm > inch to "get a handle on it".

This seems to be a problem to many in the US where-as it is not such a problem at all for us in metric zones.

When things just had to be adapted or recognised or accepted in "inch" because the US and to a lesser extent the UK "did it that way - put up with it" are increasingly less relevant.

That's the way it is and will be.

There is no point in the US being in denial or filling the moat, closing the portcullis and lifting the draw-bridge and adopting a siege or fortress mentality.

Nobody else but the US can make the US change if it doesn't want to, but that will not stop the rest of the world "moving on" to metric.

dp
04-18-2008, 11:09 PM
how do we know it is not 1 1/4 meters:D .
What I am curious about is if you go to a metric bar and order '' a shot '' how much of your favorite beverage will you get?:confused: .
Steve

15 fathoms.

I'll be here all week. My card is next to the tip jar :)

oldtiffie
04-19-2008, 12:04 AM
What I am curious about is if you go to a metric bar and order '' a shot '' how much of your favorite beverage will you get?:confused: .
Steve

Bugger all - only lead poisoning - if I get "shot".

Otherwise a "wee dram" ( I p$ss in it).

Oh sh$t - I can hear the calls of "Sassenach" from here!!!
http://en.wikipedia.org/wiki/Sassenach
http://www.urbandictionary.com/define.php?term=sassenach
http://forum.wordreference.com/showthread.php?t=19391

In Ireland I would be "beyond the pale"

The word pale derives ultimately from the Latin word palus, meaning stake. (Palisade is derived from the same root.) From this came the figurative meaning of "boundary", and eventually the phrase "beyond the pale". Also derived from the "boundary" concept was the idea of a pale as an area within which local laws were valid. As well as the Pale in Ireland, the term was applied to various other English colonial settlements, and the Pale of Settlement, the area in the west of Imperial Russia where Jews were permitted to reside.
http://en.wikipedia.org/wiki/The_Pale

J Tiers
04-19-2008, 01:39 AM
Using the unfused strips and plugs sold in the US how can you duplicate this setup safely.


Quite simple, actually.

First, what is "safe"? The "safe, impossible to electrocute with it" current is very small. So drop out all electrocution issues.

The branch circuit is "breakered", or fused, at a certain current. Things that get plugged into it must be able to carry current enough to open the breaker without them burning open first.

Since we are talking about "wire won't melt before breaker opens" amounts of current, not "safely carry forever" amounts, the wire can be fairly small, so it needn't be heavy, unwieldy wire.

So we have practical sized plugs, just as the continental Europeans do, and still have safe wiring.

On distinct advantage of our wiring is that heavy loads are 240V, and do NOT use the neutral. Therefore they do not unbalance the circuit, and they DO reduce the amount of light blinking and voltage surges imposed on the system This is something which only recently has come up in the EC regulations.

The number of electrocutions here is skewed up by the number of dim bulbs who try to steal electric cable which is part of a 2200 or 4000 volt line..... while it is live.......

Also, in the UK I understand it is forbidden to work on your own electric service. In the US people do as a matter of course, the wire, outlets, breakers, fuses, tools, conduit, and other stuff is sold at any hardware store.

Since far more people are working on and with the electric here, the fact that the UK has anything CLOSE to the same amount of electrocutions per 1000 people means the rate is really "shockingly" high in the UK.

What this has to do with metric, I don't know.

But, per an earlier question, my "pocket scale" is in decimal inches...........

The fact that we may SAY "3/8 inch rod", or describe a screw as a "three-eighths-twenty-four" cap screw, is simply because it is easier to say than "zero point three seven five rod", etc.

oldtiffie
04-19-2008, 01:56 AM
....................................
But, per an earlier question, my "pocket scale" is in decimal inches...........

The fact that we may SAY "3/8 inch rod", or describe a screw as a "three-eighths-twenty-four" cap screw, is simply because it is easier to say than "zero point three seven five rod", etc.

Good comment JT.

I still refer to a 3/8" anything as just that - same as I would for 10mm - but in both cases I would proably measure it with a decimal device - micrometer or calipers etc.

So, as you more or less said before, provided that we all use a decimal system, the more we differ the more we stay the same.

SDL
04-19-2008, 03:23 AM
Quite simple, actually.
Also, in the UK I understand it is forbidden to work on your own electric service. In the US people do as a matter of course, the wire, outlets, breakers, fuses, tools, conduit, and other stuff is sold at any hardware store.

This is not quite the case ,our big box stores (B&Q etc) are as full of sockets, cables and breakers etc just as as Lowes and Home Depot etc, You can also still go in the local wholesaler and buy at the trade counter.

You can still do certain mods and extensions but certain types of work should be inspected. They changed the wiring colurs and put date stamps on so that they can spot changes after the new rule, but luckily some of us have still got a bit of the old colour wiring;).

Steve Larner

wierdscience
04-19-2008, 09:10 AM
Thanks loose nut - good summary.

Both systems are in use, have been and will be for a long time.

More and more stuff is specified or identified in metric and so "inch" system users have to convert mm > inch to "get a handle on it".

This seems to be a problem to many in the US where-as it is not such a problem at all for us in metric zones.

When things just had to be adapted or recognised or accepted in "inch" because the US and to a lesser extent the UK "did it that way - put up with it" are increasingly less relevant.

That's the way it is and will be.

There is no point in the US being in denial or filling the moat, closing the portcullis and lifting the draw-bridge and adopting a siege or fortress mentality.

Nobody else but the US can make the US change if it doesn't want to, but that will not stop the rest of the world "moving on" to metric.

Back the truck up,metrics aren't a problem for us at all,oddball metrics are a problem for us as there is no such thing as a universally adopted standard except for the coarse series.There is no agreement among the metric nations as to which series of fine threads will be the standard.UNC AND UNF were standardized long ago and stuck.

The pitch selections are also much better for the materials at hand,the metric coarse series are too fine of a pitch for the materials they were intended to be used on.8x1.25m should be 8x1.5m,the 1.25 pitch is a poor choice for either aluminum or cast iron.I remove 100's of stripped and broken bolts in a years time and better than 50% of the time it's the metric series that need thread inserts.They have a greater tendancy to gall and shear in the hole than does the SAE selection of pitches.

Another problem is there seems to be no agreement on a standard for head sizes.Here a 3/8 bolt NC or NF have the same 9/16' head size in all instances except structural steel fastners.The metrics we see comig in from Europe will have a 19mm head on a 12mm bolt,but an Asian machine MIGHT be 19,18,17mm.Real fun if your on your back under a car.

The automotive industry began going metric back in the 70's.Not because they love the sytem,but because they could buy parts made in 3rd world countries cheaper.The result is we wound up with mixed breed cars with sae and metric fastners mixed.This was also about the time that many US car makers began opening plants in Mexico and also about the time quality went to crap.

For us to convert would cost trillions,it would also cost the rest of the world that imports goods here money since they have tooled to our system.We would also be stuck with the same sort of limbo we have now,part metric and part sae for a very long time.We would also be giving up a perfected system of fastners for a system that barely works.

Oh and 1.250 could be anything in metric unless you include notation mm,cm,m.I had a Polish fitter that couldn't keep them sorted and he was born and raised metric so much for educating the masses:rolleyes:

SDL
04-19-2008, 01:06 PM
Another problem is there seems to be no agreement on a standard for head sizes.Here a 3/8 bolt NC or NF have the same 9/16' head size in all instances except structural steel fastners.The metrics we see comig in from Europe will have a 19mm head on a 12mm bolt,but an Asian machine MIGHT be 19,18,17mm.Real fun if your on your back under a car.

Yes bolts made to NC and NF follow a std as do ISO bolts The japanese have differnt stds as do many others.

The US did it all in house for years and the standards were followed now they are buying anywhere in the world you get that std. If the EU the US and Japan pushed for a common standard the rest would follow over time.

Steve Larner

juergenwt
04-19-2008, 04:17 PM
To the doctor - you will get 0.02 liters or 20 ml. 50 shots from a 1L bottle (depends on the bartender and whether he likes you or not.
1/2 barrel of beer commonly used for import is 50 Liters ( actually it is a 1/2 hectoliter ) but you can call it a 1/2 barrel.
Now than........ how many shots from a fifth if you can still find one, or a quart?
And how many 12oz glasses from a 1/2 barrel? Not even your bartender knows.Look it up and than go and make a bet. You will not loose.

Spin Doctor
04-20-2008, 08:17 AM
Numbers is numbers. It could be worse. There could still be somebody out there using the Roman numeral system

John Stevenson
04-20-2008, 08:25 AM
Numbers is numbers. It could be worse. There could still be somebody out there using the Roman numeral system

Yup, the bloke who made my clock :D

.

Evan
04-20-2008, 08:50 AM
Back to the electricity thing, I wonder how much energy it saves in I2R losses to use 230/440 as the base distribution voltage? Also, I wonder how much copper it saves (and therefor energy) to use 16 gauge wire as the standard gauge in home wiring (Europe does)?

Spin Doctor
04-20-2008, 09:47 AM
Yup, the bloke who made my clock :D

.

I meant on prints. Can you imagine just how weird the micrometers would look

J Tiers
04-20-2008, 10:11 AM
Back to the electricity thing, I wonder how much energy it saves in I2R losses to use 230/440 as the base distribution voltage? Also, I wonder how much copper it saves (and therefor energy) to use 16 gauge wire as the standard gauge in home wiring (Europe does)?

Probably not very much overall, if there is even a net savings at all, which there probably is not. The entire system is generally rated on the basis of equivalent losses in percent of nominal voltage. Wire gauges are chosen not to exceed that loss at full current. Naturally, all the current related losses are just that, current-dependent. So the loss at light loading is a lot less than at full load.

It is a balance of fixed plant cost vs variable costs which is covered in any basic engineering economics text. The calculations for all systems now in place were done on the basis of much cheaper coal (energy) than is available now.

The copper cost is a one-time cost, the ongoing energy losses are continuous as long as the system is in use. But to figure out the "fixed energy" cost of the copper, you can look at a gauge comparison and see the cross-sectional area difference. From that you can get the volume difference per unit linear measure. Use that and an energy per ton (tonne?) figure and you are there.

Ongoing energy loss costs that are in place 24/7 over 50 years should dwarf that. And they will be pretty consistent for either system

A good way to reduce the ongoing energy loss costs would be to use the US gauges, and the european voltage.

A direct check of 12 ga (US) vs 16 ga wire (your statement on europe) shows that 16 ga has 2.5 x more resistance. Therefore, to have ANY advantage, the european circuits must be limited to less than 8 amperes maximum.

I note that the voltage is 2x, the wire resistance is 2.5x. So the power available per circuit must be lower. If not, the losses are HIGHER in the european system.

Evan
04-20-2008, 11:14 AM
It's I squared Jerry. If the current is half then for the same resistance the loss is 1/4. For double the resistance the loss is still 1/2 at half the current. Also, the maximum current permitted on a 15 amp circuit is 12.5 amps. I don't know what the max is in Europe.

J Tiers
04-20-2008, 01:43 PM
It's I squared Jerry. If the current is half then for the same resistance the loss is 1/4. For double the resistance the loss is still 1/2 at half the current. Also, the maximum current permitted on a 15 amp circuit is 12.5 amps. I don't know what the max is in Europe.



At 240V, with 3% voltage drop, which is about 7V, you deliver 233 VA/amp to the load, and waste 7W in the resistance, per amp.

At 120V with 3% drop, which is about 3.5V, you deliver 116.5 VA per amp to the load, and waste 3.5W. But you need double the current, so you actually deliver 233 VA, and waste 7W in wire resistance.

Remarkably similar numbers.

clutch
04-21-2008, 06:11 AM
You need to drop the silly 110 volt first and learn what ring mains are.
Then we might let you use a metric rule :D :D

.

I looked into that. On one level, it does seem like a clever idea. We use 120/240 from a center tapped transformer so that the neutral currents tend to go to zero.

I wired my shop with 12/3 so that my branch circuits share a common. At worst, a twenty amp 120v circuit carries 20A on the neutral. Normally though, the loads on one, side are balanced by loads on the other side taking the neutral current down near zero. This method of wiring eliminates one conductor in a run.

Now your method of connecting both ends of a feed would reduce resistance of the circuit at the cost of more wire. I'm curious, for a 20A circuit what gage wire is normally used? Here we would normally use 12 ga in romex.

As far as the 120v/240v our arraignment provides that even using 240v there is at most 120v to ground if you get involved in the circuit. :eek:

Clutch

aboard_epsilon
04-21-2008, 06:41 AM
we've gone metric here clutch ...remember ...
the wire for this circuit which will be 30 amp is 2.5mm

so our plug sockets are supplied with double 2.5 mm conductors # (between 10 and 11 gauge)

http://www.diydoctor.org.uk/project_images/ringmain/ring_main.jpg


edit

probably got that wrong

our cable is 2.5mm "square" is actually something like 1.78 mm
and between 15 and 14 gauge
all the best.markj

J Tiers
04-21-2008, 08:30 AM
Using the "15 to 14 " gauge wire, and two paths to the outlet, you have the effect of a single wire of approximately 12 gauge, but it is split in two.

Your system allows the 30A for a 12 ga wire equivalent, where the US system limits 12 GA to a 20A breaker.

Not only that, but your 30A may be preferentially flowing through the shorter path to nearby outlets, with the longer path around the 'ring" carrying less normal current, and much less fault current. It only takes 3 items to pull 30A, with 13A plug fuses. That could pull 20A through one 15ga wire, and 10 through the other, depending.

Our 20A breaker is corresponding to 16A continuous long term current. "Molded case" breakers are limited to 80% of rating long term. Long term is for something "on" continuously, like electric heaters, or motors, etc.

There is another difference between US and EC fuses..... An EC fuse carries its rating continuously, and does not blow until a much higher current. I have the figures, but not at hand right now.

A US fuse is expected to blow at currents not much over its rating, and would be used for lower continuous currents.

So the two fuse systems are quite different.

Also, common "5 x 20" EC fuses, of the glass type, may "break" only 35A. Higher currents they may totally fail to interrupt.

Similar EC fuses of the ceramic type may be rated to "break" currents only up to 1000 A, and fail to interrupt higher currents.

ALL US 5 x 20 and 3AG fuses must break 10,000A, that is, they must interrupt currents up to that level. This means that a fuse will reliably interrupt any fault current it is likely to be subjected to, without danger of fire. This is not necessarily true of EC fuses.

Note that the breakers SHOULD interrupt the current, but have a longer delay time because they are mechanical. The fuse is intended to prevent damage in the intervening time.

The US system is very heavily weighted towards safety. The EC system puts a "price" on safety, and accepts a lesser standard in some respects to save money.

John Stevenson
04-21-2008, 09:24 AM
Also, common "5 x 20" EC fuses, of the glass type, may "break" only 35A. Higher currents they may totally fail to interrupt.

Similar EC fuses of the ceramic type may be rated to "break" currents only up to 1000 A, and fail to interrupt higher currents.

ALL US 5 x 20 and 3AG fuses must break 10,000A, that is, they must interrupt currents up to that level. This means that a fuse will reliably interrupt any fault current it is likely to be subjected to, without danger of fire. This is not necessarily true of EC fuses.




This is a totally ridiculous statement

A glass 5 x 20 fuse is limited to 35A because a fuse this size will only carry that max.
Expecting a 5 x 20 fuse to carry 1,000 amps is impossible, it will vaporise long before that.

Making statements like this will nullify any rational statement you have made previously.

If you do expect a US 5 x 20 fuse the handle 10,000A that explains the magic smoke ? :D :D

.

aboard_epsilon
04-21-2008, 09:52 AM
the circuit is rated at 30 amp.......but you can put a 20, 16 ,10 amp mcb in it if you wanted to.thereby making it as safe as you want.

the 2.5 ring is usually actually covered by a 36 amp mcb. type B...plus an rcd in the consumer unit

for motors etc .you can sustitute type D

all the best...markj

davidwdyer
04-21-2008, 10:26 AM
When moving to Brazil, I thought I should be sure to have a good supply of metric tools. I also imagined that I would have to become a little more "metric." Here everything is in Kilometers, liters, etc. BUT when you go to buy a screw, nut or bolt GUESS WHAT, everything is in inches. Threaded rod comes in 1/2, 1/4, etc. If you want a metric bolt, you can find it, but it is not nearly so common. The other day I needed a couple of 1 inch inside thread, 18 tpi stainless nuts. No problem. The second place I checked had just what I needed. So, is there something inherently more attractive or seemingly "right" about this inch/foot system when it comes to threads? Of course, all the cars here have metric bolts, except the ones which don't.;)

Carld
04-21-2008, 10:31 AM
Leave it the way it is, Imperial/Metric.

clutch
04-21-2008, 04:33 PM
This is a totally ridiculous statement

A glass 5 x 20 fuse is limited to 35A because a fuse this size will only carry that max.
Expecting a 5 x 20 fuse to carry 1,000 amps is impossible, it will vaporise long before that.


.

Protective devices are rated in AIC, Ampere Interrupting Capacity. The home stuff seems to be 10,000 AIC and the comercial QO breakers weigh in at 22,000 AIC.

When a particularly nasty fault occurs current likes to keep flowing. Some times across an ionized path.

I saw where a 30A 480v three phase extension cord got dropped into water and took down the 4000A main breaker in the power room. It ignored the 30A fuses in the disconnect and the 200 Amp fuses in the branch feed. The sound of the wires in conduit doing the jump was quite impressive. Sounded like a rifle going off.:eek:

Clutch

rustyswarf
04-21-2008, 07:10 PM
The Metric System is simply a different system from the English Measure System. The real truth is, It is not Better; just different.:eek:

J Tiers
04-21-2008, 11:28 PM
This is a totally ridiculous statement

A glass 5 x 20 fuse is limited to 35A because a fuse this size will only carry that max.
Expecting a 5 x 20 fuse to carry 1,000 amps is impossible, it will vaporise long before that.

Making statements like this will nullify any rational statement you have made previously.

If you do expect a US 5 x 20 fuse the handle 10,000A that explains the magic smoke ? :D :D

.

I can only assume that you have taken leave of your senses. Actually, I think you didn't ask for leave, you are AWOL.

besides, you don't have senses, they were all penced upon long ago, and there wasn't any cents TO them in any case.

Not to speak of the fact that if you leave them in the case, they aren't any good to you. And how will you get the leaves IN there unless you open it up?

As mentioned, it is breaking current.

If you don't think 1000 amps will break that little fuse, then you can light it yourself, but the best advice is for you to you to run away fast once you have done it.

With a normal vice, it would be bad enough, but an ADvice is three times stronger, and as Evan will tell you, that is vice SQUARED, so it is really nine times worse. You'd have to run as fast as you can just to keep from falling into it, and a great deal faster if you want to get away.

I've seen vice compared to which that would seem to be a virtue. Or a pair of pliers.................

We're going to turn you in to the A.I.C. for making such statements. And won't you look funny then.............. Especially if we make you put on that pair of pliers.

:p

gellfex
04-22-2008, 02:35 PM
I just shipped one of my contraptions to Australia, and they requested it be made metric. The biggest pain, besides having to look at a table before choosing every drill, was the previously mentioned "course thread" issue. The commonly available (McMaster) screws were terrible in 60xx aluminum and worse in acetal. I actually had to use sheet metal screws in some cases rather than risk stripping of those fine "course" threads.

It seems about every 15 years I get one of these jobs, and now I have over 100 lbs (~45 kilos?) of metric cap screws for the next one in 2022.

MCS
04-22-2008, 04:37 PM
It's just a matter of getting used to. Here in Europe it's all metric, we don't have assembly problems, other than the normal ones, like gorilla mechanics.

If I compare a normal to me M6*1 bolt to a 1/4" bolt the last one looks a bit spooky. Coarse, thinnish inner diameter, easy to stretch.

It's just different and metric means just that the sizes are in millimeters.

Like there is normal M10*1.5, the Japanese use M10*1.25 for brake banjo bolts, European standard for these is M10*1.

It's all invented to make our lives miserable, to buy more taps and dies, even gears for your lathe, but with metric only, you have only halve the misery.

Metric has the majority, live with it, the British adapted within one generation. That I consider a miracle.

Norman Atkinson
04-22-2008, 06:08 PM
My earlier posting seems to have gone into the 'mists' of time. Mists means something else in Dutch!.

So you lot have the Euro. Does that mean that I can write a cheque drawn on a French bank account in Euros and cash it in Holland? Now I have a French account drawn on the Credit Agricole in the Savoie. I have also a Spanish account on Banco Santander so can I credit my Abbey account in England? Both , folks, are owned by the same company.

Real cases. So I gave a Spanish car so can I pay its insurance to a company which is registered in Switzerland with a cheque in Euros- drawn on a Fench bank account.
I can, of course, pay cash in Euros.

Well, come on- tell us? I know the answers!

Norman

I'm then going to describe the pounds and ounces thing that went to Brussels, eh?

oldtiffie
04-22-2008, 08:53 PM
Just so that this thread doesn't degenerate into a another war (sniping, slamming, attrition etc) can we get back to whether the USA should "go metric" or not or whether it is in its best interests - and for that matter for all countries - to "have a foot in both camps" (Metric and Imperial) - as is largely the case now?

It seems fair to say that most countries represented in this thread do have a foot in both camps in practical terms and seem to cope pretty well.

Ignoring the "other" system is just that - ignorance/ignorant - as they are both current and functional and will be for a long time to come.

Australia is "metric". I have no problems with the day-to-day "nuts and bolts" issues as most of us here cope with that.

Lead-screws and micrometers are all decimal anyway on both systems.

Digital equipment including but not limited to calipers, height guages and DRO's and even CNC programs can switch between both systems without missing a beat.

Most conversion is only a simple factor.

There is not much that is too "exotic" or difficult in coping/dealing with both systems in the Shop.

Just about everthing else is covered in the inside of the front and back covers of the more recent "Machinerys Handbook"

Inch or metric is all the same so long as we are dealing in decimals. Its the fractions that are the main difference as regards ease of use in calculations.

It seems to me that as we are all part of the wider integrated world that we just have to adapt to and work with each others preferred systems of measurement.

Being offended or too defensive (or abusive) when someone else queries your countries system doesn't help.

Neither does being too narrow-minded and just trying to ram "your" system down the throats of users or supporters of a system other than your own preferred system.

That is a case of people talking "at" rather than "to" each other.

That sort of approach does not seem to be productive or conducive to rational discussion at all.

So lets get back to reasonable discussion or just close off the thread or let it lapse and "move on".

dp
04-22-2008, 10:49 PM
One thing I like about metric measure:
http://www.abbeyclock.com/gearing8.html

Norman Atkinson
04-23-2008, 03:16 AM
Tiffie,
It was an older 'wise saw' than either of us who said 'A little learning is a dangerous thing'
It is important to put people who will influence and be influenced with what is not the 'hype' of an untutored media or a politician's lackey.

Frankly, I am happy to be able to adapt to a variety of formats and languages and so on.Today, America is moving into a situation where it has to chose a set of new rulers. That decision is not to be influenced by me apart from telling people what the truth is.

The truth is that the confusion or whatever word covers it was responsible for the death of a man. 'Metrication' killed an ordinary man. The ordinary man was a simple market trader who sold bananas. He sold them to ordinary people like you and me for years in pounds which was-MCS- what the ordinary people understood( 454 grammes) and lost business by being forced to quote his prices only in kilogrammes.

The case rolled on, he was taken to court and refused to pay his fine. He therefore went to prison. The strain of events for this little man was too much. Finally, the ruling was overturned but our little man was DEAD.

Today, I am going to the market next to Sunderland- and I will buy bananas in both measures- the old Avoirdupois and the new metric.
In case none of us know what the old word means it translates as French- Having of weight.

At least, you all know of why I took the matter up so strongly.

'A man died for a pound of bananas'

And today, is St George's Day!

Good Morning

Norman

John Stevenson
04-23-2008, 03:56 AM
Norm,
Definite delivery to do to Newcastle tomorrow, I'll pop in.

.

Norman Atkinson
04-23-2008, 04:39 AM
Hi John, #see E-Mail please

Cheers mate. I'll report on fuel probs ,if any- later-- Grangemouth strike

Norm

oldtiffie
04-23-2008, 11:29 AM
One thing I like about metric measure:
http://www.abbeyclock.com/gearing8.html

Thanks Dennis.

I read your post earlier but was in a hurry and so put it aside to be read again.

That article/link makes the point that the metric module/ar (Mod) and inch diametral pitch systems have a lot in common even to cutters in a set for each module/DP with each cutter suitable for a range of number's of teeth.

It also made the point that fractional or decimal (parts) of Mod and DP can be catered for. That is rarely if ever mentioned elsewhere as all situations seem to be "fudged" to suit whole Mod or DP. In those cases the pitch circle diameters and meshing gear centre distance are "adjusted" to suit the whole numbers - which is they should be to cut whole teeth!!!

It was great to see a "real world" and "non set-piece" example!!

It is amazing as to how some gears can be so distorted or "out of true form and mesh" and still function quite adequately in and for their intended purpose. One of those really distorted/mis-shapen gear sets was exactly the same as Grannies wringer (mangle??) that she used to fasten onto her wooden or concrete troughs!! And they were cast and took a real belting and outlasted Granny!!!.

http://en.wikipedia.org/wiki/Mangle_%28machine%29

Swarf&Sparks
04-23-2008, 11:42 AM
Got her whats caught in the mangle? !!! :eek:

oldtiffie
04-23-2008, 12:01 PM
Got her whats caught in the mangle? !!! :eek:

Err-r-r-r-r.

Seeing as we are in polite company here Lin and given that we both always conduct ourselves as we should when the Vicar comes to tea, I guess I should say that Granny got her mammary glands caught in the mangle.

Perhaps Grandad should have been using the mangle? No way! He was that fat and lazy that his "man-boobs" were bigger than Grannies!!

And just to prove that this is not OT, I'd bet that neither considered whether the gears were "metric modular" or "diametral pitch".

In fact that mangle did not look too unlike the rolling mill at our local steel mill.

I've seen plenty of mangled English on here as well. Was that put through Grannies machine as well?

Should I fill in an OH&S report?

Swarf&Sparks
04-23-2008, 12:08 PM
As long as the pressure angle was constant Mick :)

"Ma! cover up the bloody bird! The vicar's comin up the drive."

mwechtal
04-23-2008, 12:39 PM
I wonder if anyone here has seen this? Brion Toss is a very well known sailboat rigger on the West Coast. I particularly like his explanation of the utility of the Fahrenheit scale, and of French carpenters re-inventing the foot.

The Metric System: Pidgin Measurement (http://briontoss.com/education/archive/miscjuly00.htm)

Mike

Swarf&Sparks
04-23-2008, 01:30 PM
That's fine, as long as you want to chuck up 18" and knock off a 1/4" or so, give or take a 16th

dang
04-23-2008, 04:08 PM
There's a reason everyone else uses it, IT'S EASIER!

Swarf&Sparks
04-23-2008, 04:29 PM
Uses what?
A mangle?

juergenwt
04-24-2008, 01:28 AM
Everybody back to hogsheads and stones. And next lets bring back the model "T" and have a man with a red lantern walking in front. Don't forget the gas light - it did work - or didn't it? And on and on..........! Next time you go to the dentist - ask for the old time treatment.

Norman Atkinson
04-24-2008, 03:17 AM
I'm all for the Firkin- of ale. Again, the Brits still weigh themselves in stones which is 14 pounds avoirdupois. Again, we still drink in pints-despite MCS's claim otherwise and we still drive in miles per hour and do our miles per gallon in fuel. Again, we still do feet and inches. I am still over 6 feet tall and weigh 11 stones which is the same as 60 years ago- and wear the same suit which is 40 regular/ I wear shoes which are 9 or 10 and I know what size 43 is.
After all, it is not that long ago since Britain went 'dismal' and changed to a decimal currency. I took a firm with 1.3million consumers through it.

Where everyone gets lost is the fact that we all are using the 'half inch' for socket drives and the sparking plug sizes are imperial and wheel diameters are imperial.

OK, but stop there- a cotton pickin' minit, and look at Europe.
I live in Spain so I should be in a place where everyone speaks what is called Castillian Spanish- as used in Madrid. However, the capital of the province is Barcelona and they should, at least speak Catalan but not so, the should then speak Mallorquin which is the main island in the Balearics but no, they are speaking Menorquin. OK, this is merely the 'patois' or common speak. Not so, official documents are being written in Menorquin and not Castillian Spanish. My deeds are old and in Castillian but my car tax receipt was not.

So this is Spain, what about France? The South has 'nationalistically( is this a word) gone to the old Langue d'OC which is almost Catalan. The Basques in their desire for independence are blowing up trains and buildings.

It is not as simple as you are being led to believe.

Norm-
and looking at that, Norman is actually French and the Queen still signs Acts of Parliament in Norman French dating from 1066

La reine l'avisera?

J Tiers
04-24-2008, 08:10 AM
And next lets bring back the model "T" and have a man with a red lantern walking in front.

Sorry pal, the flagman was a much earlier version, By the time the "T" came around, the auto had been accepted. I think the flagman was probably the German contribution....... or maybe UK.

[quote]Where everyone gets lost is the fact that we all are using the 'half inch' for socket drives and the sparking plug sizes are imperial and wheel diameters are imperial.[quote]

Correct on socket drives.

Wrong about plugs..... they seem to be metric, here. Tire sizes seem to be metric also, at least partially, given I believe in cm.

Norman Atkinson
04-24-2008, 08:33 AM
J,
Sparking plugs were certainly Imperial and I recall that they were made in 2 pieces- and that we fitted 2 per aircraft cylinder- they were on Gypsy engines in the RAF. Again, I recall two sizes- vaguely. Further than that, I am not going to argue.

Regarding the tires- the quotation was for wheels not tires/tyres.

The Red Lantern is wrong but it is a Red Flag following the death of William Huskisson MP during the Rainhill Trials. these were in the earliest days of steam. I apologise having to Google because I knew much of the locomotive story but got a bit confused between Manchester for the Rainhill stiff and the Darlington stuff. I knew that it was Huskisson that was run over, however.

The next test, JT, is for you to tell me why the railway gauge is 4 feet 8 and a half inches. It's an odd Imperial size but why? Anyone else?

And which river was involved with a slide gauge? Now then, that is one for which one could almost go on the Dole.

Cheers
Norm

malbenbut
04-24-2008, 09:21 AM
4ft 8 inches was the track of Roman vehicles. I'm sure you will remember them well Norman as they would have been around when you were a young man.
MBB

Norman Atkinson
04-24-2008, 10:36 AM
After all,Malcolm, you live North of the Roman Wall. How you must have missed civilisation as the rest of us know it! You are quite right!

But what of the slide gauge? I gave you a clue. The next one is not the Great Whinsill Dyke of basalt which forms most of the Roman Wall and Northumberland National Park but another one. What about 'Jurassic Park'?
Cheers, mate
'England shall many a day tell of the bloody fray when the Blue Bonnets came oe'r the Border'

Norm

J Tiers
04-24-2008, 10:35 PM
J,
Sparking plugs were certainly Imperial and I recall that they were made in 2 pieces- and that we fitted 2 per aircraft cylinder- they were on Gypsy engines in the RAF. Again, I recall two sizes- vaguely. Further than that, I am not going to argue.



Maybe on your 1927 Gypsy Moth trainer, but I can assure you that US spark plugs are METRIC THREADS and don't you forget it.....

I have in my hand a plug out of a Briggs engine, or the like, and it is most certainly an M14 x 1.25 thread.

Automotive sparkplugs likewise.

As far as I know it has been this way for a long time. Albert Champion was a Frenchman, after all.

oldtiffie
04-24-2008, 11:40 PM
4ft 8 inches was the track of Roman vehicles. I'm sure you will remember them well Norman as they would have been around when you were a young man.
MBB

Thanks Mal.

I knew that as I had to chase it up when at a "get-together" on my retirement I was presented with trophy by some Contractors that worked on some Contracts I used to manage. It was the rear end of a horse - the veritable "Horse's Ar*e"!! Suitably presented and engraved!! Wives were there and they loved it!!!.

That led me to "Google" "horses ar*e" and of course the "ruts in Roman Roads" story emerged.
http://www.urbandictionary.com/define.php?term=horse's+arse

Now, it seems that it was "Rocket Science" from start to finish.

Stevenson's "Rocket" used it and so did the US NASA!!!

But it may not be the fault of the Brits the way it ended. The US/NASA apparently (had to??) incorporate it into rocket science!!!
http://news.softpedia.com/news/What-Is-the-Link-Between-a-Horse-039-s-Arse-and-Space-Shuttles-53408.shtml

I used to work in Weapons Research Facility which included the "Woomera" Rocket range in OZ. No horse-sh$t there but there was no shortage of Bull-sh*t though.

Lots of "horses ar*es" too - I think they bred 'em.

Its all too obvious that it "rubbed off" on me - big time - isn't it?

Norman Atkinson
04-25-2008, 03:29 AM
Tiffie et al,

The 4foot 8 and a half inches thing comes from the Roman Wall which still has the ruts of the chariots shown. Stephenson merely copied the intervals and waggons in timber wagonways which ran down to the wherries or keels which went down the Tyne to the sailing ships and thence to the World.
The place still has the song 'The Keel Row' and 'Blow the Wind Southerly' as well as 'The Blaydon Races' which were NOT held in Blaydon. They were held in Ryton where I was born. Stephenson lived across the river at Wylam.

I deliberately romped off with the slide gauge question because Vernier was a Frenchman and lived in a little village called Ornans on a tributary of the Doubs, near to Dole- a township. I thought that the clock/watchmakers would jump because Ornans is next to Bescancon which has a museum.
The area is in the Jura Mountains- next to Switzerland.

Talk about flogging a dead horse!

As the news breaks, Stephenson's High Level Bridge across the Tyne is re opening soon and the Swing Bridge next to it had to have the Roman wooden piles pulled before construction could start.

I deliberately dropped the Rainhill Trials in to raise the remark of the London to Brighton Car Rally-- Yes, Jerry, old cars some without plugs as we know them. The Rainhill had as one of the guests, a certain Mr Babbage.

Don't they teach history anymore?

Norm

franco
04-25-2008, 04:05 AM
aviemoron,

Quote: "Sparking plugs were certainly Imperial and I recall that they were made in 2 pieces- and that we fitted 2 per aircraft cylinder- they were on Gypsy engines in the RAF. Again, I recall two sizes- vaguely. Further than that, I am not going to argue."

Sorry, but I beg to differ. All the Gypsy (Major) engines I had anything to do with used 14 mm plugs, though they usually had imperial sized hexagons on them. At one stage in the fifties the correct plugs either got scarce or expensive, can't remember which, and the local aero club and some private owners were using ordinary automotive Champion L10s in all their Tiger Moth and Auster Gypsy 1s with no ill effects.

franco.

Norman Atkinson
04-25-2008, 05:31 AM
I am delighted to be reminded about the old Gypsy engines. Unashamedly i was going back to an earlier time because the Gypsy was an engine which was originally cobbled from assorted odds and ends. So we both may be right.
If I am wrong, then I apologise. I am going back almost exactly 59 years to the 21st April( Queens Birthday) 1949 and we had enormous sparking plug problems on our Proctor 3 and 4's on RAF 31 Squadron which was based at RAF Hendon which is now the RAF Museum. There was oiling up problems and we lost a crew of three. It is so clear in my mind that I recall the Gypsy had run over hours but when the wreckage was extracted the gaps were 6 thous on both plugs in No1 'pot' and should have worn beyond the normal 11thous.

It was a liitle more complicated. The aircraft had secret code books aboard and it was Boothman of the Schneider Trophy -S6B stuff- that was there- and all Hell was let loose.
To be honest, I wasn't too arsed about the plug dimensions. There was a guy out there who had already cracked his way through one unit and seemed to have got into another of our ploys.
The job was to find him.Oddly, I knew that someone who spoke suberb Engish but had been first under German occupation and then Russian was 'a dead ringer' Oh, yes! He never made it home- wherever that was.

So I had a wee bit more to do with my time than worry about metrication!

Austers- Yes- ours had skis and floats. The story of them- well, I wrote it.
I also translated the Oz unofficial motto for our sister Squadron. I read' Don't f*** us about'
Cheers

N

malbenbut
04-25-2008, 06:52 AM
Is oldtiffie and norman brothers? Their posts are quite similar in style has any one else noticed this.
MBB

aboard_epsilon
04-25-2008, 07:17 AM
Is oldtiffie and norman brothers? Their posts are quite similar in style has any one else noticed this.
MBB

I've noticed that

did they go to the same public school :D

all the best..markj

Norman Atkinson
04-25-2008, 07:18 AM
Malcolm,
Poor old Tiffie!
The answer is probably that we both go back to fundamentals.
I would have thought that my reference to vernier would have incurred the wrath of every tool maker on the planet.

Unless one knows mathematics and the history of mathematics, one doesn't get very far. Old Tiffie knows his way around Euclid and Pythagoras.

Well, you did ask

Norm

And Mark, to answer your point.
I left school at the age of 14. It was an elementary school in a ****ty pit village on Tyneside and 1944 was in the middle of a war where education as YOU know it, didn't exist.

oldtiffie
04-25-2008, 07:39 AM
Is oldtiffie and norman brothers? Their posts are quite similar in style has any one else noticed this.
MBB

Thanks Mal.

The answer is: "Yes and no".

We both went to "Public Schools" in the "Government/State" variety and not the "Private" as in "Privileged" as in Eton, Rugby or Oxford nor Cambridge. aka "School of hard knocks" - as well as the Military.

Norm and I are interested in measurement and lay-out with old-fashioned tools and we have had similar progressive chequered careers.

Perhaps it was my earlier chequered career that got me a Draftsman's job - teaching and practicing it - or vice-versa?.

I hope I have laid some of these shiboleths to rest.

http://en.wikipedia.org/wiki/Shiboleth

Clear(er)?

Yes?

No?

Hmmm-m-m-m-m

Norman Atkinson
04-25-2008, 08:26 AM
Humm! Shibboleth?????? An aspiration by Ephraimites who were--------
A clamourous and turbulent people- or so it is written.

How history can be traced and repeated

Norm

Emmm,Oil and wine and corn after a winding staircase. Mathematically very interesting.

malbenbut
04-25-2008, 08:46 AM
Quote
Old Tiffie knows his way around Euclid and Pythagoras.

I've never been there but the wife's been to Crete.
MBB

Norman Atkinson
04-25-2008, 09:08 AM
More Hmmms! Crete????? Well, I refered to a winding staircase not to a labyrinth.
Sounds like a lot of old bull to me.

You know the legend? Oh, dear, Oh, dear.

Beware of Greeks bearing gifts and Troy. Back to troy weights, Malcom!
How clever of you.

And Tiffie, back to horses, eh?
To Hellen Be Merry.

Norm

oldtiffie
04-25-2008, 09:12 AM
Quote
Old Tiffie knows his way around Euclid and Pythagoras.

I've never been there but the wife's been to Crete.
MBB

Thanks Mal.

It really is a small world.

She probably met me and my "rellies" - we are all Cretins.

http://en.wikipedia.org/wiki/Cretin

I can assure you that Euclid had more success with his "Propositions" that I ever had with any that I made. Perhaps I made a series of Elemental errors.

http://en.wikipedia.org/wiki/Euclid

http://en.wikipedia.org/wiki/Euclid%27s_Elements


I have had my Urologist check my postulate but all I got was a good time and "the finger" and his account.

http://en.wikipedia.org/wiki/Postulate

But.

Just so that this is not too "OT", the Urologist must have been a good Machinist/HSM-er as I can assure you that he used the correct "way oil" measured in "gill" or "fitting a quart into a pint pot?". Hardly - the reverse - certainly.

Norman Atkinson
04-25-2008, 09:41 AM
OT, I for one two, had ' prostrate problems' Urine good company.

It's one way I suppose of making eyes water. Get a urologist.
( Now mine was half Scots and half Chinese and was female- I was Black and Deckered!) She had a funny handshake come to think of it. She had a horse- poor bloody animal.

Talk about the Five Points of Fellowship- nope, better not

Cheers

Norm

oldtiffie
04-25-2008, 10:04 AM
Quote
Old Tiffie knows his way around Euclid and Pythagoras.

.................................................. ..............
MBB

Hi Mal.

When you have nothing better to do, try sorting this out:
http://en.wikipedia.org/wiki/Pythagorean_theorem

It is a good read.

Norman Atkinson
04-25-2008, 10:40 AM
C'mon Tiffie,
the easy solution is the Red Indian one.
Should we elucidate? Nope, better not.

I was a 'candidate' and there was this thing on the wall to the right of the Chair of Soloman. I suddely said 'Do I have to prove it?' to my guide.
'Do you mean that you can do it?' he relied. 'Yea, by constructing congruent triangles'

Leaving school at 14? This is where I came in- not ended.

And Malcolm,
if you are in the Chantry in Morpeth, most of the exhibits are from my days sitting at the feet of a master- Will Cocks, who taught me to use a lathe in 1941 amongst other things. None of this Wacky pedis stuff then.

Norm

malbenbut
04-25-2008, 11:40 AM
oldtiffie and norman have now gone off in another tangent,time this thread was locked.
MBB

Deja Vu
04-25-2008, 11:57 AM
oldtiffie and norman have now gone off in another tangent,time this thread was locked.
MBB

No really! I was thinking they were out in a spiral/helix and would crash and burn on their own :D

Norman Atkinson
04-25-2008, 12:16 PM
Perfectly good engineering stuff. I mean to say that for once we are getting a standard where some 'berk' isn't asking something which could have been answered by buying or borrowing an elementary book on enginering.
Maybe we have woken people up to the fact that there is that bit in life which is not the surprise when a tool is set tangentially to the work and a bit of metal just rolls off- like by accident.

Come on, engineering is not a black art only privvy to those who have carried cups of tea for most of what should be training.

I worked long into the night to get my training-after work- and every night for years.

Lock the thread if you must- and hide the truth!
n

Deja Vu
04-25-2008, 12:34 PM
Perfectly good engineering stuff.
Lock the thread if you must- and hide the truth!
n

I've always wondered....just who is "THE ONE" who locks the threads if deemed absolutely necessary?

I personally don't feel ANY thread should be locked...if it IS locked, it should be good enough reason to completely remove it.

John (bloy)

Norman Atkinson
04-25-2008, 12:47 PM
The topic of Metrication in the US is about as ethereal as one can get.
There is no one on this forum who can influence any of the decisions.
The decisions will be made by economic factors far outside the scope and indeed the pockets of the likes of us. Consequently, we might as well have a good old rant about it.

There is only one thought- mathematically.
Each person in the US with a right to vote has only one vote. What is the percentage of power of each person? For those who can't do math, it is almost the square root of bugger all.

Norm

Deja Vu
04-25-2008, 03:31 PM
aww shucks...
I'm out of the worry as to whether or not standards are set.
I simply have tools for both imperial and metric.
...AND, since I'm kindof a tool collector myself, I'm always filling in the gaps/missing tools. :)

oldtiffie
04-25-2008, 06:58 PM
Norm and Deja Vu have got it right.

There is no need to lock this thread - just stop posting to it unless you've got something to say that needs saying - as somebody well might - so give them the chance.

No one here is going to or can change anything in regard to metrication - of the USA or anywhere else.

Many here are not going to change their minds irrespective of the merit/s or otherwise of anyone else's-s case/s.

It has got to the stage where the discussion is repetitious, circular, tangential and OT.

And above all else - its now boring.

Let's just let it fade away into oblivion.

John Stevenson
04-25-2008, 07:01 PM
Let's just let it fade away into oblivion.

Until next time.........................


.

J Tiers
04-25-2008, 09:08 PM
The funny thing is the extent that the US IS ALREADY metric.......

And the two getting the most fun out of this topic aren't even IN the US.

IOWOLF
04-25-2008, 09:37 PM
Back to the original topic, The U.S. has been Metric, I shoot a 5.56mm, 7,62mm, 5mm, 9MM, 10MM and a 12.7mm.

Norman Atkinson
04-26-2008, 02:50 AM
Tiffie,
We are, well, I am 'undone' Jerry has finally spotted the wind up.

The next question is 'Where next in our disrespectful old age?'
Back to the theatre box in the Muppets?

Norm

Bigger and better lampoons, I say

Spin Doctor
04-26-2008, 11:07 AM
My boss at work was complaining one day about the reluctance of the US to go metric. I explained to him that it had more to do with the FFFFFFFFFFFFrench having developed the metric system as anything else. I also explained to him why the French plant shade trees along all of the roads and streets. That's so the Germans can march in the shade (both he and the owner are German)

Deja Vu
04-26-2008, 11:14 AM
My boss at work was complaining one day about the reluctance of the US to go metric. I explained to him that it had more to do with the FFFFFFFFFFFFrench having developed the metric system as anything else. I also explained to him why the French plant shade trees along all of the roads and streets. That's so the Germans can march in the shade (both he and the owner are German)

Now there's a real "spin" on the subject!!:D

Norman Atkinson
04-26-2008, 01:43 PM
Following the Franco Prussian'wind up', the following came from my 'other brothers'
The AP and the UPI newswires have reported that the French Government has raised its terror alert level from 'Run' to 'Hide'
The only higher levels are @Surrender' and 'Collaborate' The rise was precipitated by a recent fire, which destroyed France's White Flag factory, disabling theiir mlitary.
The Italians have increased their alert level to 'shout loudly and excitedly' to 'Elaborate military posturing' Two levels remain, 'Ineffective combat operations' and 'Change sides'
The Germans also increaseed their alert status from'Disdainful arrogance' to 'Dress-up in uniform and sing marching songs' They have two other levels 'Invade a neighbour' and 'Lose'
Seeing this reaction in continental Europe, the Americans have gone from 'Isolationism' to 'Find somewhere in the Middle Ease ripe for regime change' Their remaining alert states are 'take on the World' and 'ask the British for help'
Finally, The UK has gone from 'Pretend nothing is happening' to 'Make another cup of tea'. Higher levels are 'Remain resolutely cheerful' and 'Win'

And if you wish to complain change 'Freemasons' to read 'Rotary International'
and you have never heard of me.

Norm

J Tiers
04-26-2008, 02:28 PM
What is it about "les Go***mns" that leads them to dump on the French so much?

I have an entire arsenal of rude words to describe Brits, or Germans, but, surprisingly, nothing of the sort for French, Irish, or Swedes. :D

Well, "Micks" for Irish, but that's really for the "imports" so it's actually another term for Brits........

The Metric system, and the Police State, are the "gifts" of the French in retaliation for past insults...... :p

So far only one of them is "sticking", but we can wait longer..........

TECHSHOP
05-18-2008, 06:11 PM
One of you over there said there was a new standard:

Working on "the latest, greatest" project, I encountered this fastener:

1/2 inch diameter
12 threads per inch
60 degree "V" angle
19mm hex head (some of my 3/4" wrenches/sockets fit, but all my 19mm wrenchs/sockets fit)

Is this Cantonese Standard Whitworth?

and please remember that:

"28.35 grams of prevention is worth 0.4536 kilograms of cure"

juergenwt
05-18-2008, 09:11 PM
J Tiers - Looks like you have not traveled very much. You would be surprised to hear some names for the French , Irish, Swedes and yes - for the Americans.
But than again - some people may just be a little more polite than others. I think, we should all thank Napoleon for introducing the Metric System to the world.
You may not remember what happened in the early days of the Space Race.
The Navy got the job to catch the Russians and build the first US spacecraft using the imperial system of measurement. After many tries Kennedy turned the job over to the Army team using metric.
There is only so much you can do with an old system. Sooner or later you have to abandon it.
Just like an old aircraft design - no matter how good it was, you can only make so many improvements - than you have to abandon it.
The Imperial system is way overdue for the junk yard.

J Tiers
05-18-2008, 09:54 PM
J Tiers - Looks like you have not traveled very much. You would be surprised to hear some names for the French , Irish, Swedes and yes - for the Americans.


Oh, I have been many places, all over europe, for one thing, and not in hotels, either, but camping. I have heard many bad words, mostly back when the invading hordes of Germans on motorcycles came through when everyone in Germany went on vacation, and most went to Italy...... and a few to Yugoslavia....

Oh, such language from the Italians, Serbs, and even Croats! Back then, most didn't mind Americans at all, but the memory was very fresh, shall we say....... only 20 years........ Of course, the French hate everyone, but that is just what we do. :)

However, my point was that I have "conveniently forgotten" ;) all the names for French, Swedes, and Irish, not that there aren't any. I am sure there are many bad names for Americans, and even a lot of bad names for Tibetans, for that matter, and Americans have made more trouble than Tibetans.


The Imperial system is way overdue for the junk yard.

No doubt.... but how to get it there? If you make a law that all imperial machines must be scrapped and nothing done in Imperial, it would be unconstitutional, as well as an economic nightmare.

There is a huge problem when 200 years of industry has used a system, and you decide to change overnight.

After all, the US actually "went metric" 130 years ago....... it just takes a long time to percolate through.....

wierdscience
05-18-2008, 10:34 PM
You may not remember what happened in the early days of the Space Race.
The Navy got the job to catch the Russians and build the first US spacecraft using the imperial system of measurement. After many tries Kennedy turned the job over to the Army team using metric.
.

Really?I have several relics from the Mercury and Appollo programs,all are SAE.Cryogenic valves,fueling transfer valves and until recently two titanium fuel cells,all where SAE.

Funny too is the fact that the Russians never made it the moon and we did,must say something about that metric system:D

ckelloug
05-18-2008, 10:40 PM
One has to remember too that NASA lost a Mars probe to unit conversion. IIRC, a fuel capacity calculation was done in imperial measures by those designing the probe while the guidance guys who were using the fuel were doing the navigation in metric and ran out of fuel. I'm sure somebody remembers said incident much better than I do.

--Cameron

oldtiffie
05-18-2008, 10:47 PM
I thought that this topic and thread had been safely laid to rest. Seems not - or that it ever will be.

It keeps re-emerging like the heads of the Hydra.

Perhaps we need Hercules to undertake his second labour with this as well!!

http://en.wikipedia.org/wiki/Lernaean_Hydra

J Tiers
05-18-2008, 10:54 PM
One has to remember too that NASA lost a Mars probe to unit conversion. IIRC, a fuel capacity calculation was done in imperial measures by those designing the probe while the guidance guys who were using the fuel were doing the navigation in metric and ran out of fuel. I'm sure somebody remembers said incident much better than I do.

--Cameron
That is a factor not of the systems, but of a failure to co-ordinate the units concerned..... assuming it really happened as-described, which is fairly odd in and of itself.

It could equally have happened if one used kg and the other used liters..... They would not be equal for fuels, just for water at STP. You MUST agree on all units, procedures, etc, up front whenever there is a transfer of information.

Not to mention that apparently, if true, there was a severe lack of any check..... generally there must be a "sanity check" by an uninvolved person to make sure that any "assumed knowledge" is actually shared by all participants. NOT to do that is to risk exactly such a problem, even if everyone is supposedly using one system.

When there is a chance of using different systems, it is doubly important, of course.

Nope, that is a basic project management oversight, and is really, at base, NOT blameable on units or measuring systems. it could have happened in a modified form if the SAME units were used by all.

juergenwt
05-19-2008, 12:59 AM
J Tiers - everyday we loose on exports while the metric system takes time to percolate through. Isn't it time to make a final cut? Those old machines will be around another 75 years - will we?
If most of Europe was able to change to a unified currency with a few years of preparation and than an overnight change - we can do the same thing.
There is one problem. To many people wondering what we would call the "Inchworm" or what to do with the football field etc. etc.
The thing is: " It does not hurt enough" and with the decline of our manufacturing sector, not that many people are affected by the lead weight our industry has to carry in a race with the rest of the world. Sad story.

Some time ago, after the government first decided to have all roads built to metric dim's and forced the construction companies to do all their calculations in metric, only to get cold (political) feet and made an about face on most of the requirements I listened to the conversation of two concrete workers (over lunch). They were trying to figure out how much concrete to use on a small project. It was a disaster until one of them said something about not having the right charts or tables to come up with the correct figure. After a short pause one of them said:" You know, it was very easy when we had to do it in metric, now we are back to using tables and charts again".

No J Tiers - all that is needed is a government that has the political will to lead.Otherwise all we need is a bunch of clerks to govern by plebiscite. Once in a while we have to expect our elected men and women in Washington to take a stand on something that may not be all that popular but will benefit our nation. I do not expect any leadership from this nor the next group on the hill. They have only one goal - get re-elected.

oldtiffie
05-19-2008, 03:35 AM
I am with juergenwt here.

We pretty well went "cold turkey" here in OZ. Inch was illegal at first for a while although they relented on that. Otherwise its 100% metric.

Best thing we ever did - bar none.

We can still use and buy "inch" steel, drills, tools etc. as well as metric and it works very well indeed.

Some stuff - like foot-ball fields - was "hard converted" to exact metric equivalents. Other stuff was "rounded off" to the metric preferred increments, and the rest/most of it just went 100% metric.

As I've said previously, anyone who only works in decimal inch is pretty well there as it is only a 25.4 conversion factor from inch to metric and 1/25.4 for conversion of mm to inch.

If you really want to see how rational the metric system is - have a look inside the front and back covers of machinery's Handbook (well, my 27th. Edition anyway).

J Tiers
05-19-2008, 08:10 AM
Silly silly metro-centric people........... Think they are the only smart ones.

Arrogantly assuming that people in the US do not use metric, don't understand it, CAN'T understand it, etc.............

Surely some do not.

But, I went to high school and college a LONG time ago ( I was draft age for Vietnam). Metric measurements were in common use for all technical subjects BACK THEN.

Still are.

Oh, yeah, BTW, I played "football" in high school, too....... YOUR "football".

Anyhow...........

I wouldn't know what to DO with a "slug" (except load it) or a "poundal", etc.

I am not particularly fond of the newer SI magnetic units, but that is largely because many vendors, SOME IN THE EC, don't consistently give specs in SI. And I tend to forget which unit name is which, since there are I think 3 different systems.

The biggest pain in my backside right now is having to convert FROM MM dims TO decimal inches for some vendors. The native drawings are in MM.

With CAD its really easy for the actual model size, but the dimension lines etc on the hunman-readable drawings usually get fouled up in the conversion.

wierdscience
05-19-2008, 08:33 AM
Silly silly metro-centric people........... Think they are the only smart ones.

Arrogantly assuming that people in the US do not use metric, don't understand it, CAN'T understand it, etc.............

Surely some do not.

.

You mean the folks who don't know about decimal inches and can't wrap their brains around something as simple as fractional math:rolleyes:

loose nut
05-19-2008, 10:26 AM
everyday we loose on exports while the metric system takes time to percolate through. Isn't it time to make a final cut? Those old machines will be around another 75 years - will we?


That equipment will be here in 75 years because companies can't afford to get rid of it on a metric whim. Canada is a metric country but industry is still mostly imperial, old equipment must be replaced and upgraded and it is done with imperial based equipment (England, Australia and others would be the same), ripping out older parts just to make it easier to replace them with metric parts is to expensive. Your not talking millions or billions of dollars, it's hundreds of trillions of dollars of existing imperial based equipment still in use around the world and it's not going any were. Many other metric countries still use the imperial system to some degree "officially" and "unofficially".

Let the people here who have to deal with the metric system because of international trade or whatever worry about it.The metric system will eventually take over completely but it won't happen soon.

Why should the average European, Ausi or Japanese for example care what system the average American or Canadian use on a day to day basis, we have very little direct contact that would make using the same system that important. Do the people in metric based countries need validation that they did the right thing by changing over, does the fact that some people don't like metrics make you feel like you made a mistake.

Use what ever system you want, just leave us alone to do what we want.

juergenwt
05-19-2008, 02:23 PM
Loose Nut - Gen. Motors found out the cost of converting to metric was 1% of the original estimate. Like I said before - you can hang on to your old machines and may I say it was very good equipment and could last for ever, but sooner or later you will have to stop throwing good money after bad. It would have been a lot better if our government had the backbone to set a deadline for an orderly changeover and the faster the better. Everybody on it's own does not work very good and adds to the cost.
We see how it can be done by looking at the TV change over to digital. Draw a line - that's it. This time industry was on board - but I suspect that is because there is no TV manufacturer left in the US. Are we going to wait until
the rest of our industry goes the same way?
I can assure you that a company owned by somebody from outside the US will have no objections to a rapid change to metric.
As far as "the American people do not understand metric" - that is just not true. They all know how to count money. What almost nobody in the US knows, is the "Imperial" or in our case the "US Customary System" .
Pls. go and ask your bartender:" How many 12oz glasses from a 1/2 barrel"?

bob308
05-19-2008, 04:24 PM
i was not going to get in this but there is nothing standard about metric.

in inches a 3/8 bolt has a 9/16 head. in metric a 8.8 mm bolt can have a 12,13 or a 15 mm head. now that make for some real work when you have a machine of fork lift or car with 8.8 mm bolts and a bunch of different size heads on them.

loose nut
05-19-2008, 04:55 PM
Juergenwt, If it was that simple or cost effective it would have happened already, the move to global metrics isn't so much economic as political. On top of that there are some people who can't stand having anyone who isn't just like them and want to force everybody to be the same. Why should I have to change my backyard shop to be the same as a factory in Japan or China just so we would use the same system. I've heard all the pro metric arguments and not one can answer that.

SDL
05-19-2008, 05:19 PM
i was not going to get in this but there is nothing standard about metric.

in inches a 3/8 bolt has a 9/16 head. in metric a 8.8 mm bolt can have a 12,13 or a 15 mm head. now that make for some real work when you have a machine of fork lift or car with 8.8 mm bolts and a bunch of different size heads on them.

I've not seen 8.8mm bolts 8mm grade 8.8 yes, but the head size is related to the bolt size not the grade.

Steve Larner

bob308
05-19-2008, 05:30 PM
ok i was off on the dia. but they still have 3 different head sizes. i know i just worked on a forklift that had them.

J Tiers
05-19-2008, 09:58 PM
The cost of conversion CAN be low. The cost CAN BE MADE HIGH......

It is all in how you do it....

A legislated cold turkey flip-over, with penalties for using imperial units and imperial machines, would indeed be very expensive....... WAY TOO expensive.

Just the mere cost of replacing EVERY SINGLE highway sign that referenced a speed or distance would be very high. For european countries, with 3 distance-related signs and two speed limit signs in the whole place ( :p ) it looks cheap..... but not so here......

So the exact way that a law reads could have unintended consequences, requiring crazy expense.

Then also.......... We already HAVE lots of metric things..... the "2-liter" soda bottle, for instance.....

But, do you force all things which are now in even numbered traditional units (1 pound containers) to now only use even numbered METRIC amounts (1 kg, or 0.5 kg, etc containers only) ? OR do you allow the 1 lb containers, and just require that they be labeled in kg first and most prominently (and pounds second)?

A seemingly small thing like that could make literally billions of dollars difference, when packaging lines, and package manufacturing etc must all be changed-over.

Contrast that with a change to a label, which is typically done once a year just for marketing, and so is cheap.

Sounds so simple, when you just say "well just change-over cold turkey"...... but there are lots of details which might make it so expensive if done wrong, that many more companies might be driven overseas.

juergenwt
05-20-2008, 12:39 AM
Just what is an 8.8 mm bolt???

juergenwt
05-20-2008, 12:42 AM
Loose nut - you do not have to change your backyard shop.

juergenwt
05-20-2008, 12:58 AM
One question: would you like to sell to any other country in the world?
Second question: do you like to covert all ingredients from metric to "imperial". Scientists, Chemists, the medical field and all research works in metric - so do we keep on converting? I don't think so. This is called "the dumbing down of America". TV does it all the time - weather, space, world reports, medicine etc.etc..You do not have to force anybody to change, only to make the metric system the standard for the US industry - not the "preferred system" as the government likes to call it.

tdmidget
05-20-2008, 02:18 AM
The reason that the aerospace industry is stuck with inches is that any change , even a fastener will require that the item be recertified as an airworthy design.

My pet peeve is the use of the term "imperial". Just which empire are you taliking about? German, French, Spanish, Portuguese, Italian, Dutch, Ottoman, Japanese, Evil? All metric. If you mean English or British, say so. Inches and feet, pounds, gallons are ENGLISH measurements. As far as I can tell they were never used outside of the british empire.

Peter N
05-20-2008, 03:02 AM
This tired old subject keps coming up again and again. Nothing wrong with either system if that's what you're comfortable with.
I work with both, but definitely have a preference for metric. However, I frequently think and work in both systems, and this is quite common over here in the UK.

'Boris' over on the PM forum managed to capture this approach quite succintly, as he said:


"Seeing as I'm British, I'll give the run down of how a modern british engineering type person thinks

From 0 to 0.001" I use microns
From 0.025mm to 0.1mm I use imperial
From 0.04" to 1" I use metric
and anything above 25.4mm I use imperial

Boris"

Peter

John Stevenson
05-20-2008, 03:42 AM
If you mean English or British, say so. Inches and feet, pounds, gallons are ENGLISH measurements. As far as I can tell they were never used outside of the british empire.

So the USA is still part of the British Empire ?

If so can we have our lease lend payments back ?

.

oldtiffie
05-20-2008, 04:05 AM
Perhaps its time to take it all out of the realm of "think so" and place it into the "know so" category.

Perhaps not surprisingly, most of the former British Colonies - with one notable exception - have "gone metric".

Perhaps this might help.

http://en.wikipedia.org/wiki/Comparison_of_the_imperial_and_US_customary_measur ement_systems

http://en.wikipedia.org/wiki/Special:Search?search=imperial+measurement&fulltext=Search

MCS
05-20-2008, 04:43 AM
Just what is an 8.8 mm bolt???

Should be: what is an 8.8 bolt?

It's a quality grade.

First number is breaking limit, in this case 800 Newton per square millimeter.
Second number is elastic limit, 0.8 * 800 = 640 Newton per square millimeter.

Wikipedia:

"On Earth's surface, a mass of 1 kg exerts a force of approximately 9.81 N [down] (or 1 kgf). The approximation of 1 kg corresponding to 10 N is sometimes used as a rule of thumb in everyday life and in engineering. "

The metric system integrates calorics(?), forces, torque, size etc.

oldtiffie
05-20-2008, 08:00 AM
This is the Wikipedia page on metrication:
http://en.wikipedia.org/wiki/Metrication

This lists the various bolt specs:
http://en.wikipedia.org/wiki/Bolted_joint

This is how we implemented it in OZ:
http://en.wikipedia.org/wiki/Metrication_in_Australia

This is the history of metrication in the USA:
http://en.wikipedia.org/wiki/Metrication_in_the_United_States

This is the story of metrication in the UK:
http://en.wikipedia.org/wiki/Metrication_in_the_United_Kingdom

J Tiers
05-20-2008, 08:31 AM
One question: would you like to sell to any other country in the world?
Second question: do you like to covert all ingredients from metric to "imperial". Scientists, Chemists, the medical field and all research works in metric - so do we keep on converting? I don't think so.

A moment's thought will show that these points have already been addressed......

Also:

Please do NOT assume that all in the US are using imperial. A trip through the grocery store will show that.

Please do NOT assume that inches somehow force the use of fractions, either..... A very common assumption among foreigners.

Please do NOT assume that the US "has yet to convert to metric". The US has been OFFICIALLY METRIC for well over 100 years...... That is how long the metric system has been "legal for trade", a necessary provision.

ANYONE is free to use metric. I do, at work. My previous work also used metric measurements, hardware, etc. We exported millions of $$ to foreign countries who use metric mainly.

I tend not to at the home shop, simply because I have a lot of non-metric stuff, as well as machine leadscrews, etc, and so I use BOTH inch and MM mics, calipers etc......

There is this smug and superior attitude among foreigners that the US does not own any metric rulers even......

What IS lacking here is the police state FORCING the scrapping of inch machinery, the provision of jail time for using inches, etc.

Since the origination of the metric system WAS in a police state, perhaps there is an association of the metric system WITH police states. Nearly ALL the original metric countries are now, or have been, police states.

Apparently it requires a police state to make the conversion in the way that many would like to see it...... forced, with penalties, and maybe house searches for any inch equipment and roundups of inch users. ('Raus, 'Raus !)

The metric system is ALREADY pervasive in the US....... But quantities and lengths have not necessarily been all forced-over to integer MM and kg, etc.

The inch system is STILL present in your foreign countries..... you have admitted to pipe sizes, and then mauch is still sold in traditional pounds, and your metric socket wrenches snap onto inch-sized drivers....

oldtiffie
05-20-2008, 09:21 AM
Well, as the US has the "clout", power and inertia to do, or not do, as it likes, if it likes and how and when it likes - that's the way it will be - especially as regards metrication.

For the same reason, there's no point in/of us "foreigners" even trying to convince or convert the US - its an excercise (by the "foreigners") of futility and stupidity - so we don't and won't even try.

I suspect that the US is "inching" toward metrication never-the-less albeit very slowly and reluctantly??

loose nut
05-20-2008, 07:42 PM
Loose nut - you do not have to change your backyard shop.


It will if I'm unable to buy imperial drill, taps and dies, measuring equipment etc. or materials.

Why would anyone from Europe or Asia care if the US or any other country is metric or not, Does it matter that Americans measure mileage in miles or pump there gas in gallons or buy there food in in pounds,it has no effect on other countries.

Let the people who deal in the Global world worry about dealing with metrics and leave the average person would doesn't alone to do as they want.

Most of the pro metric arguments quote the use of arcane measurements that haven't been used for years, and as for the fraction question how do metric based countries calculate compound gear trains etc. without fractions, if there is some "magic metric matriculation" on this topic I personally would like to know.

oldtiffie
05-20-2008, 08:27 PM
Loose nut - you do not have to change your backyard shop.


It will if I'm unable to buy imperial drill, taps and dies, measuring equipment etc. or materials.

Why would anyone from Europe or Asia care if the US or any other country is metric or not, Does it matter that Americans measure mileage in miles or pump there gas in gallons or buy there food in in pounds,it has no effect on other countries.

Let the people who deal in the Global world worry about dealing with metrics and leave the average person would doesn't alone to do as they want.

Most of the pro metric arguments quote the use of arcane measurements that haven't been used for years, and as for the fraction question how do metric based countries calculate compound gear trains etc. without fractions, if there is some "magic metric matriculation" on this topic I personally would like to know.

Thanks loosenut.

I will answer your very "on topic" post in your paragraph order:

Para 1:
I expect that like here in OZ, you will always be able to buy all your SAE/ASME/Unified and BSW/BSF/BSP/BSgas etc. threading stuff, spanners, sockets and plate/rod/bar etc. in "inch" just as we can - and we've metricated for a long time. I guess we are "bi-lingual" as are many in the US and UK. We "metricated" people respect the US right to do as it likes as regards metrication.

Para 2:
We don't as it really is none of our business other than as an interest.

Para 3:
As said - we do.

Para 4:
That is not quite right as the Driver1/driven1 x driver2/driven2 .............. = ? is more a formula than a fraction. All formulae with a numerator and a denominator -whether in metric or inch - are in that category and are usually solved with a computer or calculator - in decimal and not in fraction form. I think that what is meant is this sort of stuff: ((1/32" + 5/8" + 3/16") x (4 3/4"))/(22/7 x 4 1/2) That is a bit extreme but it is a PITA to do other than by decimal ie a calculator. All angles are usually given in decimal degree as it is a PITA to convert to and from Deg.Min.Sec. ie 23.735 deg = 23 733/1000 deg = 23 deg 1 32/1000 min = 23 deg 1 min 1 9174/10,000 sec = 23 deg 1 min 1.92 sec Even the venerable old book of logarithms was in decimal. The old trig functions in DMS were a total PITA compared to decimal degree.

Many of us in the metricated countries still have and use "inch" tools and machines - just as it is in the US.

The super-market still sells tinned stuff (jams, spreads etc.) in "pound" except that it is marked as 454 gram. MOst are in the preferred metic system (Kg, gram, metre, mm). There are any amount of similar examples. We get used to them. Many people still use "pound" for birth-weight of babies. They use it for their own height (foot, inch) and weight (ton). The big problem with all of that is that the kids are only taught metric in schools and so the "inch" system is pretty much a new language. Talk of dozen or mile or gallon really confuses them. So teaching your kids machining on an "inch" machine with inch micrometers etc. can be quite a problem.

So, as you infer, the metricated countries (OZ anyway) still has significant "legacy" issues from its "inch" era.

J Tiers
05-20-2008, 10:29 PM
And that is exactly what is happening here......

To say nothing of the fact that the chinese care nothing for the US market anymore, and ship metric here regardless.

wierdscience
05-20-2008, 10:43 PM
And that is exactly what is happening here......

To say nothing of the fact that the chinese care nothing for the US market anymore, and ship metric here regardless.

To a point,it did bite them in the but when they shipped several container loads of 4-1/2" angle grinders here wth the bastard 14x2mm spindle.Nobody bought them and the whole lot where scrapped.

Our importers have learned their leason and will no longerbuy anything that is non-standard for fear of losing money.

wierdscience
05-20-2008, 11:01 PM
In the world of machinery there is but one thread system that is a standard.The unified system UNC and UNF are global standards and the threads along with the heads attached are the same regardless of where they are made,sold or used.This is not true of metric where only the coarse series are a set standard.

Now we have pipe of which the global standard is based on British imperial which was and still is very much based on the inch.

Adding these facts with the final flaw which is poor pitch selection in metric fastners there is no reason that we should give up SAE fastners ever.

Now if you guys across the pond would reform those crappy pitch selections to something that sucks less we might think about it:D

As for the rest of measurement,the average person on the street doesn't measure anything.They go to the store and they buy the size they think looks right not caring if the jar of peanut butter is one quart or one liter.

SDL
05-21-2008, 03:46 AM
In the world of machinery there is but one thread system that is a standard.The unified system UNC and UNF are global standards and the threads along with the heads attached are the same regardless of where they are made,sold or used.This is not true of metric where only the coarse series are a set standard.
.

A bit like the world series now days a international std with hardley anwhere else playing:D .

All local UK distributors of fasners i use have binned UN and whitworth series a good few years ago.

I worked at a place that made special purpose macinery 30 years ago and they had gone metric then.

In the end cost will drive it, here we can still get them if we try same as BA but metric is a lot cheaper.

Steve larner

aostling
05-21-2008, 05:39 PM
Tire codes contain an odd mixture of units. My Forester uses a size 215/60R16. The 215 is the tire width in millimeters. The 60 after the slash is the aspect ratio -- the height-to-width ratio expressed as a percentage. R denotes radial construction. The 16 is the wheel diameter expressed in inches.

This code is used world wide, even in so-called "metric countries."

lazlo
05-21-2008, 06:06 PM
So the USA is still part of the British Empire ?
If so can we have our lease lend payments back?

Hey now, we sent you $30 Billion in weapons, tanks, trucks, aircraft, food, supplies, medicine and raw materials in return for - ahem, lease of military bases in Newfoundland and the Caribbean.
If you want your $30 Billion back, you'd better start finding all that sh!t we sent you :)



"Seeing as I'm British, I'll give the run down of how a modern british engineering type person thinks

From 0 to 0.001" I use microns
From 0.025mm to 0.1mm I use imperial
From 0.04" to 1" I use metric
and anything above 25.4mm I use imperial

That's fascinating Peter!

When you read through some of the Model Engineer articles when the U.K. was switching over, the blueprints are maddening: Imperial dimensions with Metric bore sizes, and completely random (Metric, Witworth, Imperial) fasteners. It's like a test to see if you could possibly assemble the damn thing! :)

oldtiffie
05-21-2008, 08:10 PM
....................................
......................................
When you read through some of the Model Engineer articles when the U.K. was switching over, the blueprints are maddening: Imperial dimensions with Metric bore sizes, and completely random (Metric, Witworth, Imperial) fasteners. It's like a test to see if you could possibly assemble the damn thing! :)

Hi laslo.

It gets better or worse (depending upon your preferences) as I think that you might find that modern machining centres may be "native" metric and "fudged" for use in inch. The machine may work very well in inch but the machine itself is or may be made to metric standards.

You may also find that a lot of stuff made in the US is in fact metric - especially any that might be exported to other (mostly metric) countries. Same might well apply with stuff imported which may be made to metric standards which are in fact hard conversions of the US-preferred inch sizes.

I, and many other - usually "older" people have no trouble using either or both systems as the job or machine requires, but many - particularly younger people - have no idea or concept of what the "inch" system is and when they do find out, they just (usually "hard" but sometimes "soft") convert it to metric. This of course gives rise to the "mixed" systems and conversions as well as the errors that are more likely to creep in.

It is mainly about economic but particularly "ease of use" in a "consumer/retail" environment.

It seems easier now for metric countries to just ship metric to the US and conversely harder for the US to sell or ship "inch" to metric countries. If manufactured in the US on inch machines the inch sizes may well have to be hard conversions of the metric equivelant/s.

This may be quite a significant problem in a globalised market and economy.

But as said any amount of times previously, the dual "inch/mm" systems that we have will still be available and used for quite while yet.

wierdscience
05-21-2008, 08:50 PM
A bit like the world series now days a international std with hardley anwhere else playing:D .


Steve larner

At least all teams are playing the same game with the same size bat:D

loose nut
05-21-2008, 10:13 PM
Para 4:
That is not quite right as the Driver1/driven1 x driver2/driven2 .............. = ? is more a formula than a fraction. All formulae with a numerator and a denominator -whether in metric or inch - are in that category and are usually solved with a computer or calculator - in decimal and not in fraction form. I think that what is meant is this sort of stuff: ((1/32" + 5/8" + 3/16") x (4 3/4"))/(22/7 x 4 1/2) That is a bit extreme but it is a PITA to do other than by decimal ie a calculator. All angles are usually given in decimal degree as it is a PITA to convert to and from Deg.Min.Sec. ie 23.735 deg = 23 733/1000 deg = 23 deg 1 32/1000 min = 23 deg 1 min 1 9174/10,000 sec = 23 deg 1 min 1.92 sec Even the venerable old book of logarithms was in decimal. The old trig functions in DMS were a total PITA compared to decimal degree.

.

Tiffie, you are technically right but they still look like fractions. If it walks like a duck........

oldtiffie
05-22-2008, 03:29 AM
Tiffie, you are technically right but they still look like fractions. If it walks like a duck........

Thanks loosenut.

Only fractionally.

If said ducks "shi**ing ducks" are in multiples/powers of ten they should be decimated.

Or metricated?

Sorry.

Not.

dp
05-22-2008, 11:45 AM
Because the inch is now based on the standard meter I'm going to keep using inches. Besides, having a 98 cm waistline is just not flattering.

derekm
05-22-2008, 01:16 PM
[QUOTE=lazlo]Hey now, we sent you $30 Billion in weapons, tanks, trucks, aircraft, food, supplies, medicine and raw materials in return for - ahem, lease of military bases in Newfoundland and the Caribbean.
If you want your $30 Billion back, you'd better start finding all that sh!t we sent you :)
...QUOTE]
BTW it was only a loan (no Marshall plan for the UK, but resumption of pre-war economic warfare) which took us until 2006 to pay back, but the terms of loan included letting the pound float(sink) as a currency which resulted in economic collapse and rationing of food until 1952 (1947 Daily mirror headlines "sold out for a packet of fags" (fags are cigarettes). As regards bases there was Diego Garcia in the Indian ocean as well as the UK bases. So we paid for that sh!t :)

juergenwt
05-22-2008, 04:35 PM
John - pls. tell me you are joking!