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.RC.
04-13-2010, 06:47 AM
Just had an idle thought today while going fore a walk as to how the metric system seemed to run out of puff when it came to things like time, degrees etc..

I believe there probably was a system thought up where time is based on a factor of ten and same with degrees... And I am sure some thought was put into changing the moon and earth orbit to a more metric friendly figure..

I guess I should stop having idle thoughts and instead have thoughts on movie stars and sports stars like the sheeple..

djinh
04-13-2010, 07:14 AM
Not sure about metric time, that would seem a bit cumbersome... But the real world uses radians to calculate with angles, so no need for a metric standard there :)

MuellerNick
04-13-2010, 07:27 AM
Are you referring to Burma, Liberia or USofA? These are the countries needing some more puff.


Nick

Evan
04-13-2010, 07:34 AM
Degrees were invented by the Babylonians because the number 360 has more factors than any other number of similar size which makes calculation very simple. The same applies to time as it is directly associated with the measurement of angles in degrees in astronomy (which does not use radians). The primary unit of spherical angle subtended in Positional astronomy is The Greenwich Hour Angle, aka the Sidereal Hour Angle and the Right Ascension, also measured in degrees. The primary unit of distance is the Parsec which stands for the Parallax Arc Second.

Changing either the units of time or the units of angle would cause incredible confusion in a wide number of fields from aircraft navigation to building construction and surveying.

oldtiffie
04-13-2010, 08:36 AM
Ringer,

try this.

Not all angles are measured in degrees or radians either.

Understand this and you can say you have graduated.

http://en.wikipedia.org/wiki/Grad_(angle)

J Tiers
04-13-2010, 09:05 AM
Close this worthless thread........

We all know that the US has been officially metric for 130 years, so let it DIE already.

Peter.
04-13-2010, 09:22 AM
Let America die? Who would us Brits have available for vocabulary-correction if that happened?

Dunc
04-13-2010, 09:26 AM
Well, Canada is "officially" metric. Speeds are in kilometers, meat priced by the kilo, but...
2 x 4s are still that, gyproc (wallboard) is 4 ft x 8 ft panels. Funny, tho, most kitchen cabinets adopt the euro metric standards.

Someone mentioned metric time. When metrication first came to Canada there were a lot of upset citizens. One April Fool's day a radio talk show host entered the fray. He talked about the changes to kilograms in the supermarkets, the use of kilometres and kph on the highway system and asked for listener reaction. There was little: no increase of call ins. Then, he stated that the big change was still to come. The federal government was going to change to metric time: 100 sec/min, 100 min/hr and 10 hours per day. The calls became torrential before the good listeners realized that they had been 'had'.

John Stevenson
04-13-2010, 09:38 AM
I did the same, back in 1972 we made the change over to metric, the biggest change over was with money.
We had to hand in what we had and get it changed for new, there was an interim period when both were valid.

At the time I was working for a local transport company with a large fleet of lorries.

Our yard was quite small as the lorries parked up in a local works for overnight loading. the drivers used to queue on a private road outside and wait to get in the yard to diesel up. One of my jobs was to go down the line and ask for defect sheets and check lights etc.

We always had a crack with the drivers, anyway one night as this metric money was coming it it became the talking point as you would expect. I told the drivers that the following month we were changing to metric time, 10 hours am, 10 hours pm.

Well to a driver this makes a lot of difference, drivers hours breaks etc and they all got upset about it.
That much so that unbeknown to me they had an unofficial meeting and stormed into the office to tell management they weren't prepared to accept it.

Of course management knew nothing about this but the drivers read this as them trying to hide the facts. :rolleyes: :rolleyes:

Caused quite a hoot.................

.

goose
04-13-2010, 09:54 AM
If I recall, they did try to metricize time, to an extent. They being FNA (French National Assembly) at the time of the French Revolution. Did they not have 10 day weeks?


Gary

Spin Doctor
04-13-2010, 10:03 AM
The sun may of set on the British Empire but the legacy of the Great Enemy lives on in the Metric System and the Napoleonic Code.

mayfieldtm
04-13-2010, 10:13 AM
Last week or so, NASA announced that it's abandoning the Metric System.

That's one giant leap forward.

Tom M.

wierdscience
04-13-2010, 10:15 AM
What about all the metric standards that aren't really metric? Metric roller chain and pipe come to mind.

TGTool
04-13-2010, 10:27 AM
One wonders that the French didn't change the year to metric as well. 365 1/4 days per year is such an inconvenient number someone really ought to tidy that up soon.

Evan
04-13-2010, 10:31 AM
Last week or so, NASA announced that it's abandoning the Metric System.



No they didn't. They asked for one specific exemption for one specific DoD program called "Constellation". The request has been denied.

http://www.spaceref.com/news/viewsr.html?pid=33782

John Stevenson
04-13-2010, 10:32 AM
The sun may of set on the British Empire but the legacy of the Great Enemy lives on in the Metric System and the Napoleonic Code.

The only reason the sun never sets on the British Empire is God wouldn't trust an Englishman in the dark :rolleyes: :D

.

Evan
04-13-2010, 10:35 AM
Then how come Lucas didn't strangle on his own umbilical cord?

Black_Moons
04-13-2010, 11:12 AM
Canadas adoption of metric is.. bizzar.

You can buy a 350ml, 500ml, 1liter or 2 liter container of.. Just about anything really
But, if you where to buy 4 liters of milk, you would be asked to buy a gallon of milk.

Iv seen blueberrys in ONE store in 3 diffrent spots far across the store, one being sold by the Oz, another by the 100g, and another by the lb.

'I don't want no stinken cheap imported chinese metric lathe/mill!' - Typical canadian/american attitude towards metric leadscrews.

I go to the metal stores.. everything is in inchs.

I go to the plastic stores... I buy 1/2" and notice that some of the plastic has metric stamps and others imperial. 'Whats up with that' 'Oh, just depends where we buy it.. the diffrence is usally not enough to matter so we just sell it as imperial'

'How tall are you' comes out in foot and inchs.
If you ask my grandparents the tempature they still respond in farenheit. (canadians)

Of course, americans arnt doing much better...
I believe shortly after slaming that mars probe into mars at 10,000kph because someone screwed up a metric/imperial conversion, nasa told everyone they where gonna try really really hard to follow thier last release saying they where gonna try really really hard to follow thier last release saying they where gonna try really really hard to follow the LAW OF CONVERTING TO METRIC for goverment agencys that had been past long ago.
I wonder what costs more.. Converting to metric, or slaming a (or several) multi billion dollar probe into the backside of mars.

And no, that wasent a 'repeat' problem, they really have issued that many press releases saying they will be trying to follow previous press releases/laws.. any day now.... :P

boslab
04-13-2010, 11:15 AM
Dont think the metric minute was ever intended, they were used for time and motion studies years ago but I think time is circular myself and degrees also, just my opinion, I like degrees, never been fussed on radians even in college, radians per second squared my butt.
mark

lazlo
04-13-2010, 11:27 AM
Is it time for our monthly Metric versus Imperial bitch session? :)


Canadas adoption of metric is.. bizzar.

You can buy a 350ml, 500ml, 1liter or 2 liter container of.. Just about anything really But, if you where to buy 4 liters of milk, you would be asked to buy a gallon of milk.

...and your beer and soda is sold in camouflaged Imperial :)

The UK is a perfect example of how painful Metrication can be -- open up any Model Engineer and there's a bizarre mixture of Imperial, Metric, and even Whitworth. And you still serve pints, and measure body weight by stone.

This is from March's Model Engineering Workshop. Dang it, where the heck do you find 6.35 mm plate stock in the UK?? :p
63.5mm long x 31.75 mm wide??

http://i164.photobucket.com/albums/u15/rtgeorge_album/Metric1.png

lazlo
04-13-2010, 11:32 AM
No they didn't. They asked for one specific exemption for one specific DoD program called "Constellation". The request has been denied.

http://www.spaceref.com/news/viewsr.html?pid=33782

LOL! Did you read the reason for the exemption request?



"We found that because the Department of Defense (DoD) has not fully embraced the metric system as the manufacturing standard in its projects, and because of the size of its contracts, DoD exerts an overriding influence on the U.S. aerospace industry. NASA officials stated that until DoD begins converting its major programs to the metric system, NASA will not be able to easily transition to the metric system due to a lack of aerospace parts designed in metric units. "

This would make a good Dilbert cartoon! :)

lakeside53
04-13-2010, 11:52 AM
My local hardware store... bearings are organized by their OD in inches... 1.850, 1.378... no one there knew they were just nice round metric numbers :) Actually, it does make it easy to see the metric bearings between the fractional -the fractional have nice round number 1.0, 0.75, 0.625...

Evan
04-13-2010, 01:13 PM
My local hardware store... bearings are organized by their OD in inches... 1.850, 1.378... no one there knew they were just nice round metric numbers Actually, it does make it easy to see the metric bearings between the fractional -the fractional have nice round number 1.0, 0.75, 0.625...


That is funny as hell. You see, in both cases you are using the exact same method of defining the size of the product, base ten decimal fractions. The difference between metric and inch completely disappears when you do that, especially if you take into account that those values are only approximate since they only fall somewhere within a tolerance band.

.RC.
04-13-2010, 05:11 PM
Close this worthless thread........

We all know that the US has been officially metric for 130 years, so let it DIE already.


The thread is not about the US nor metric/imperial superiority... Simply the fact that metric is a base 10 system and we still have 7 days in a week, 24 hours in a day. 360 degrees in a circle, etc etc...

ADGO_Racing
04-13-2010, 05:16 PM
I like Metric....No need for a tap drill chart or to memorize tap drill sizes....a tap drill for a 10 x 1.5 tap is simply 8.5mm 10-1.5 = 8.5mm. Working in the base ten system is easy.

MuellerNick
04-13-2010, 05:46 PM
Simply the fact that metric is a base 10 system and we still have 7 days in a week, 24 hours in a day. 360 degrees in a circle, etc etc...

It's very simple:
Neither day, week, hour or (radian) degree is a SI-unit. They even aren't derived units like Pa (Pascal; pressure in N/m^2).
Day week etc. are based on the second, and that's enough. They are as odd as a lightyear (well, that's a distance) but a helpful factor for a few or a many people.
Regarding the degree, it's only a helper-"unit", not a unit. It only divides a circle into sections. You won't find the degree in the SI-units. It also could not be derived from the physical base units (m, kg, s, A, K, mol and cd).
Furthermore, SI only defines physical properties.


Nick

J Tiers
04-13-2010, 07:49 PM
The thread is not about the US nor metric/imperial superiority... Simply the fact that metric is a base 10 system and we still have 7 days in a week, 24 hours in a day. 360 degrees in a circle, etc etc...


Are you referring to Burma, Liberia or USofA? These are the countries needing some more puff.


Nick


What about all the metric standards that aren't really metric? Metric roller chain and pipe come to mind.


Canadas adoption of metric is.. bizzar.

You can buy a 350ml, 500ml, 1liter or 2 liter container of.. Just about anything really
But, if you where to buy 4 liters of milk, you would be asked to buy a gallon of milk.

Iv seen blueberrys in ONE store in 3 diffrent spots far across the store, one being sold by the Oz, another by the 100g, and another by the lb. ................




Is it time for our monthly Metric versus Imperial bitch session? :)



...and your beer and soda is sold in camouflaged Imperial :)

The UK is a perfect example of how painful Metrication can be -- open up any Model Engineer and there's a bizarre mixture of Imperial, Metric, and even Whitworth. And you still serve pints, and measure body weight by stone.



Tell it to the "maroons".

Close this drivel

oldtiffie
04-13-2010, 07:50 PM
Nick makes a good point regarding circular measurement.

It has pretty well always (for our purposes) been measured in degrees, minutes and seconds (of arc), which is fine for protractors rotary tables,theodolites, inclinometers and the like.

But in both the Metric and Inch systems they require to be "decimalised" (base 10) for calculation purposes and converted back to DMS for day to day applications. It was just the same in the days before computers and calculators when we used "Castell" 4 or 6-figure tables for logarithms, and trigonometric functions where we used the tables to "decimalise" the functions, and then had to convert back to DMS. Just the same with slide rules.

I have noticed over time here that many have trouble converting between DMS and decimal degrees and reverse. It is very prone to error.

If rotary tables etc. were calibrated in decimal degree it would make life a lot easier.

Having vernier/analogue protractors calibrated in DMS and the digital protractors calibrated in decimal degrees (some do have a DMS><decimal degree function) does or can confuse or cause errors as well.

I have no problem dealing with either metric or inch or decimal or DMS angular measurements. I slip from one to the other seamlessly. I sometimes have both systems running together on the one job.

TDmaker01
04-13-2010, 08:36 PM
metric is for the weak minded, nuff said!

bollie7
04-13-2010, 09:28 PM
I have an old desktop sized, Smiths brand (made in Germany) Mechanical stopwatch here in front of me. It has a second hand and a minute hand. Calibrated, as you would expect, in minutes or seconds (depending on which hand you are watching) Interestingly though, around the outside of the face its divided into 100 divisions.

bollie7

gnm109
04-13-2010, 10:18 PM
Let America die? Who would us Brits have available for vocabulary-correction if that happened?


Yes, and your language would then die out in one or two generations, which now are approximately 12 years in the inner cities here. :)


.

loose nut
04-13-2010, 10:49 PM
The federal government was going to change to metric time: 100 sec/min, 100 min/hr and 10 hours per day. The calls became torrential before the good listeners realized that they had been 'had'.


100 sec/min,
100 min/hr
10 hours per day
10 days to the week
10 weeks to the month
and 10 months to the years.

Sounds like a plan, now all we halve to do is find a way to change the orbit of the Earth to match the new length of the metric year. Oops, maybe that's why we still have the weird old calenders.

oldtiffie
04-13-2010, 10:53 PM
metric is for the weak minded, nuff said!

All of the "inch" or "imperial" in use in the USA are defined in metric terms.


International inch
Effective July 1, 1959, the United States and countries of the British Commonwealth defined the length of the international yard to be exactly 0.9144 meters. [1] Consequently, the international inch is defined to be equal to exactly 25.4 millimeters. This creates a slight difference between the international units and surveyor's units which are described in the article on the foot.

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

and:

The pound or pound-mass (abbreviation: lb, lbm) 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.

from:
http://en.wikipedia.org/wiki/Pound_(mass)

etc. etc.

As you say:

metric is for the weak minded, nuff said!
'nuff sed.

Evan
04-13-2010, 11:07 PM
Decimal time is widely used in astronomy. It is otherwise known as the Julian date. It removes all ambiguity from the specified time that an observation was made and can be expressed to any desired degree of accuracy without causing confusion.

From the USNO:




Julian dates (abbreviated JD) are simply a continuous count of days and fractions since noon Universal Time on January 1, 4713 BCE (on the Julian calendar). Almost 2.5 million days have transpired since this date. Julian dates are widely used as time variables within astronomical software. Typically, a 64-bit floating point (double precision) variable can represent an epoch expressed as a Julian date to about 1 millisecond precision. Note that the time scale that is the basis for Julian dates is Universal Time, and that 0h UT corresponds to a Julian date fraction of 0.5.


http://aa.usno.navy.mil/data/docs/JulianDate.php

Paul Alciatore
04-14-2010, 02:48 AM
I like Metric....No need for a tap drill chart or to memorize tap drill sizes....a tap drill for a 10 x 1.5 tap is simply 8.5mm 10-1.5 = 8.5mm. Working in the base ten system is easy.

I am so tired of seeing this brought up as an advantage of the metric system. The trick is not due to the metric system, but rather due to the 60 degree vee thread used by both English and metric sized threads.

A 1/4-20 thread has a lead of 1/20" or 0.05". 0.25" - 0.05" = 0.20" or just about exactly the size of the commonly used #7 drill for this thread size.

It will work for any 60 degree, vee thread, English or metric. You just have to translate the threads per inch to inches per thread (the lead).

And if you think the metric system's use of mm per thread or the lead is a better idea than using threads per inch, just look at a thread dial for a metric lathe as opposed to one for a lathe with an English sized lead screw. Using that metric threading dial will slow you down a lot more than calculating a simple reciporical.

RancherBill
04-14-2010, 08:43 AM
I used to think that going to a day that had 20 hours would be a good thing. It would make computing what 3 days was in hours so much easier. Then I realized that one hour meeting would be longer.

My current thought would be that we move ot a system of 30 hour days.:D As a bonus to this system everybody would get a raise.:)

SDL
04-14-2010, 09:18 AM
The trick is not due to the metric system, but rather due to the 60 degree vee thread used by both English and metric sized threads.
.
No English threads were 55 degrees. American are 60:D

Steve Larner

Evan
04-14-2010, 09:35 AM
Uh, no. Whitworth are 55, British Standard Cycle are 60 and metric are 60, all three types.

Forgot one, BA is 47.5

There is also a difference in the thread form. Whitworth specifies a round crest and root.

Dilettante Machinist
04-14-2010, 09:38 AM
The only reason the sun never sets on the British Empire is God wouldn't trust an Englishman in the dark :rolleyes: :D

.


Then how come Lucas didn't strangle on his own umbilical cord?

Well played, sir.

I've been lurking for two years. I signed up yesterday so I could applaud this comeback. I used to own an MG.

Evan
04-14-2010, 09:44 AM
So did I. :D Welcome.

MuellerNick
04-14-2010, 10:56 AM
just look at a thread dial for a metric lathe as opposed to one for a lathe with an English sized lead screw. Using that metric threading dial will slow you down a lot more than calculating a simple reciporical.

Yea, that's right.
Do you turn metric threads on a manual lathe for a living? That are how many a day?
A Boley runs 3 times (not sure about the exact number) faster when in reverse. For long threads, a thread dial is a clear advantage, for short ones, I don't see it.


Nick

loose nut
04-15-2010, 07:33 PM
I am so tired of seeing this brought up as an advantage of the metric system. The trick is not due to the metric system, but rather due to the 60 degree vee thread used by both English and metric sized threads.

A 1/4-20 thread has a lead of 1/20" or 0.05". 0.25" - 0.05" = 0.20" or just about exactly the size of the commonly used #7 drill for this thread size.

It will work for any 60 degree, vee thread, English or metric. You just have to translate the threads per inch to inches per thread (the lead).

And if you think the metric system's use of mm per thread or the lead is a better idea than using threads per inch, just look at a thread dial for a metric lathe as opposed to one for a lathe with an English sized lead screw. Using that metric threading dial will slow you down a lot more than calculating a simple reciporical.


Imperial or Metric, it doesn't matter, it is still easier to look it up on a damn chart. Save your brains for something important.

.RC.
04-15-2010, 10:37 PM
Only thing I will say is metric threads were obviously invented by a mob of idiots compared to imperial threads...

Tobias-B
04-15-2010, 10:44 PM
I got told to shut up back in about 5th grade when I asked the same question-

"What about metric time?"

If Mrs. Presley's still alive, maybe she could come and yell at this thread, too...

hee.

t