The kilogram is dead: Long live the kilogram

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But you need rules and regulations for any kind of measurement system, whether it is the inch-pound system or the metric system. An inch is the same throughout the United States because of rules and regulations, and so is an ounce, and so is a degree Fahrenheit.
 
Ok.

With this post, I think it’s time to ask the mods to lock the thread... [emoji6]

The register decided long ago, these SI and imperial units were all to messy, so they invented their own:

Area (nanoWales - nW)
Force (Norris - No)
Length (linguine - lg)
Temperature (Hilton - Hn)
Volume (grapefruit - gf)
Weight - (Jub - Jb)
Velocity - (Percentage of maximum velocity of sheep in a vacuum)
Money - (Pogba - Pg)
Etc...

——————————

From the register(biting the hand that feeds IT): (follow the link, there’s a conversion calculator)

IMG_0599.jpg

https://www.theregister.co.uk/Design/page/reg-standards-converter.html

The Reg online standards converter

Welcome to the Reg online standards converter, which allows instant conversion of commonly-used metric and imperial standards into approved Vulture Central units, and vice-versa. To get started, simply make your selection from the list below and you'll be offered three sets of fields: Imperial, Metric and Reg. Enter the desired figure into any one field, hit calculate and you're in business.

Not all conversions will work perfectly. This is because here at the Reg Standards Bureau, our priority has to be preserving the accuracy of our own units. Accordingly, all our conversion factors are Reg standards.

To maintain our own high standards, we've had to shave a teensy bit of accuracy off everyone else's. For instance: there are 8 furlongs to a mile, which means 25 miles should convert to 200 furlongs. But it actually converts to 199.something furlongs. As our technical wizard explains: "To turn a mile into anything else, it first needs to be converted into linguine".
——————————
So using standard REG notation:

My 0.0031 double decker bus diameter MD flew using a motor with 1.6 (Chuck) Norris’ of impulse to an altitude of 65 Brontosauruses, reaching a maximum velocity of 0.0184% of the maximum velocity of a sheep in a vacuum.

And my JLCR is typically set to open at 1306 linguines.
 
Something I heard a long time ago was that some (most? all?) construction that uses the metric system often uses a "base" of 1.2 metres and not 1 m. That quantity being readily divided into 60, 40, 30, or 20 cm units. Anyone over Europe-way can confirm or deny?

Best -- Terry
 
prfesser said:
Something I heard a long time ago was that some (most? all?) construction that uses the metric system often uses a "base" of 1.2 metres and not 1 m. That quantity being readily divided into 60, 40, 30, or 20 cm units. Anyone over Europe-way can confirm or deny?

Best -- Terry
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The ply sheet I just bought for lining my motor/BP storage box came in 600x1200 sheets (or 1200x2400 sheets) and the dowel rods I bought came in 600/1200/2400mm increments, so there’s at least some truth to that here in Australia.
 
snrkl said:
The ply sheet I just bought for lining my motor/BP storage box came in 600x1200 sheets (or 1200x2400 sheets) and the dowel rods I bought came in 600/1200/2400mm increments, so there’s at least some truth to that here in Australia.
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I wonder if thats why Baltic Birch plywood is sold in 60"x60" sheets commonly, as 59.02" is 1500mm and that is a divisible by 300mm (and its slightly oversized to allow for kerf loss).
 
In my other life, I deal with federal alcohol excise taxes, which are set by the gallon or proof-gallon (spirits use proof gallon : 1 pfgal = 1 wine gal at 100 proof at 60F. A wine gallon is a US liquid gallon - not to be confused with a British gallon, which is based on the beer industry.)

All the allowed standards of fill are metric.

All the WI state excise taxes are on Liters.

And since I make cider and perry, I must buy apples and pears. In units of bushels. A bushel is 8 dry gallons. A dry gallon is a different number of cubic inches yet. And the conversion factor from bushels to pounds for each fruit is set by crop insurance definitions that vary by -state-

After fermentation, I may need to add various correction or fining agents, and have actually seen ounces per hectoliter on instructions.
 
jlabrasca said:
Randall Munroe is on it

kilogram.png
Click to expand...

I hadn't yet looked at this thread, but I had to look back because I knew that XKCD would show up. Simplifies everything.

FWIW, nearly everything related to 3D printing is metric. That will probably do more to sneak metric into the US than anything.

If you want to see a real mess, try laying out a printed circuit board. Different systems must mix, often in components side-by-side. Experienced layout designers think naturally in both.
 
Anyone remember the Mars Climate Orbiter?

From Wikipedia
[O]n September 23, 1999, communication with the spacecraft was lost as the spacecraft went into orbital insertion, due to ground-based computer software which produced output in non-SI units of pound-force seconds (lbf·s) instead of the SI units of newton-seconds (N·s) specified in the contract between NASA and Lockheed. The spacecraft encountered Mars on a trajectory that brought it too close to the planet, causing it to pass through the upper atmosphere and disintegrate.

The primary cause of this discrepancy was that one piece of ground software supplied by Lockheed Martin produced results in a United States customary unit, contrary to its Software Interface Specification (SIS), while a second system, supplied by NASA, expected those results to be in SI units, in accordance with the SIS. Specifically, software that calculated the total impulse produced by thruster firings produced results in pound-force seconds. The trajectory calculation software then used these results – expected to be in newton seconds – to update the predicted position of the spacecraft.

More at https://en.wikipedia.org/wiki/Mars_Climate_Orbiter
​
 
Yes, I remember very clearly the Mars Climate Orbiter disaster. If everyone the world over used just one system of weights and measures, then no one would ever have to engage in such measurement conversions and risk making errors in measurement conversions.
 
MetricRocketeer said:
Hi Nytrunner,

But rulers don't show hundredths of an inch. If you want to use a decimal system, then you should use the metric system, which is already decimalized.

Stanley
Click to expand...

Weirdly, one of the tests I do at work routinely uses a 1/100 inch scale. They're out there, just a little hard to read with old eyes. The one I use most often has tall marks at increments of 0.1, slightly shorter at 0.05, slightly shorter yet at 0.02, 0.03, 0.07, and 0.08, and short marks everywhere else. That seems to work pretty well.

I'd still rather switch to metric so I don't have to deal with speeds in furlongs per fortnight. Many boats designed in metric have frame spaced 1200mm apart. I don't know if it's rounded off of 24" or because it has many factors.
 
The Concorde supersonic aircraft was a great example of how metric and imperial could work together well. Built by UK and France, I think the UK would build the cockpit/nose section and France would build the main airframe. One was then shipped and the two were mated to form the aircraft. Went very well according to the stories. "One technical question frequently asked is: What happens about the two standards of measurements in France and Britain? The simple solution to this problem was to allow both sides to work in the scales to which they are accustomed. A common system of numbering engineering drawings was established before manufacture of the prototype aircraft began. French drawings were dimensioned in metric measurements, and British drawings in feet and inches. At interface points in the structure, the relevant drawings were dimensioned in both scales."

Either system would work, but I know what I would rather be calculating physics and engineering quantities in.
 
The story that OverTheTop just posted about the Concorde is most interesting. So, in this case, mixing both measurement units did not have catastrophic consequences. That's good.

On the other hand, consider what OverTheTop reports: "At interface points in the structure, the relevant drawings were dimensioned in both scales." What duplication of efforts! The fact is that, if the British used the metric units that the French were using, this dual dimensioning would not have been necessary.

Well, at least no accident occurred. But an enormous loss of time and staff hours -- which otherwise would not have been necessary -- did result.
 
MetricRocketeer said:
What duplication of efforts! The fact is that, if the British used the metric units that the French were using, this dual dimensioning would not have been necessary.

Well, at least no accident occurred. But an enormous loss of time and staff hours -- which otherwise would not have been necessary -- did result.
Click to expand...

I'm a metric fan myself, but the same could be said of using customary units throughout.
 
dhbarr said:
I'm a metric fan myself, but the same could be said of using customary units throughout.
Click to expand...

Hi dhbarr,

Thank you for your comment.

Using only one type of measurement units is preferable to using two types, and then having to convert back and forth. I agree with you on that (and I think that is what you are saying).

Then, however, let us choose the efficient, modern metric system instead of the inefficient, archaic inch-pound system.

Stanley
 
Get out of my head Randall...

MetricRocketeer said:
If everyone the world over used just one system of weights and measures, then no one would ever have to engage in such measurement conversions and risk making errors in measurement conversions.
Click to expand...

Bob Austin said:
Anyone remember the Mars Climate Orbiter?

... due to ground-based computer software which produced output in non-SI units of pound-force seconds (lbf·s) instead of the SI units of newton-seconds (N·s) specified in the contract between NASA and Lockheed. ...
​
Click to expand...

NASA was already measuring in SI units, and requiring measurements be figured in SI units. The contractor screwed up. Short of time-travel (or a putsch and purge of all unreconstructed engineers, technicians, mechanics, teachers, etc.) there is no way to erase legacy unit systems from the world.

A student in a lower division mechanics class asked whether she had to work some solution in cylindrical polar coordinates, which she found to be confusing and unnatural. I pointed out that the selection was not mandatory, but that radial symmetry made the solution much simpler if worked in polar coordinates, rather than rectilinear coordinates. While explaining this, I mentioned that there are 14 orthogonal coordinate systems. This was news to her. She was nonplussed. After a brief reflection, she explained that she understood the utility of polar coordinates in some cases, but that the other 12 (the names and bases of which she was wholly ignorant) seemed unnecessary and should probably be retired.

I am not sure what reminded me of her just now <smile>
 
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MetricRocketeer said:
Hi dhbarr,

Then, however, let us choose the efficient, modern metric system instead of the inefficient, archaic inch-pound system.

Stanley
Click to expand...

Define "efficient" please. What are your thoughts on Phillips versus JIS versus Pozidriv versus Quadrex?

Maybe we should just standardize on Torx?

edit: Nuts, that was supposed to be one long snark -- not two separate snarks.
 
MetricRocketeer said:
Doing 0.50 + 0.25 is easier, and thus more efficient, than doing 1/2 + 1/4.
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Not for someone experienced in working with fractions, such as with a tape measure. It all depends on what you’re accustomed to. It’s beneficial to the human mind to be able to adapt to different concepts.
 
Hi jlabrasca, Very nice and instructive photograph. Thank you.

Hi Steve,

First of all, I am honored to be addressing the president of the Tripoli Rocketry Association.

Now back to the issue at hand.

123.456789 km = 123456.789 m = 123456789 mm

Quickly, please, anyone, how many feet is 123.456789 miles, and how many inches is 123.456789 miles?

Stanley
 
Multiply by 5280 ft/mile then multiply by 12 inches/foot.

Under what circumstance do you suppose that you could not take the time to do the arithmetic?

For that matter, when do you imagine you'd need to know a distance on the order of a 100 miles down to a resolution of 0.01 inches?
 
jlabrasca said:
Multiply by 5280 ft/mile then multiply by 12 inches/foot.
Click to expand...

Such a conversion is clearly more difficult and time-consuming to accomplish.

Under what circumstance do you suppose that you could not take the time to do the arithmetic?
Click to expand...

I can imagine many such circumstances. Anyway, why not use measurement units that enable you not to have to take the time?

For that matter, when do you imagine you'd need to know a distance on the order of a 100 miles down to a resolution of 0.01 inches?
Click to expand...

I can imagine many such circumstances. Anyway, why not use measurement units that enable you to be able to do so if you want to do so?
 
MetricRocketeer said:
Such a conversion is clearly more difficult and time-consuming to accomplish.
Click to expand...

No, It is not.

MetricRocketeer said:
I can imagine many such circumstances. Anyway, why not use measurement units that enable you to be able to do so if you want to do so?
Click to expand...

Many instances of 100 mile distances known to an uncertainty on the order of the thickness of a piece of paper? That's astonishing.

And you can measure to whatever precision in whatever unit system. The things that are decimalized in SI are the named units, not measurements made in those units. Your arguments would be more persuasive if you could demonstrate that you understood that.

I want to draw up a fin-marking guide for a low power rocket. 3 equally-spaced fins around the circumference of a BT55 airframe. Explain how the use of SI units make the necessary computations easier or more efficient.

Or, I am laying out the club newsletter. How would expressing the font for the body text as "4.23" mm be more efficient than calling it out as 12 points?

dhbarr said:
Only responses in lojban or a similar conlang will be tolerated.
Click to expand...

Beltalowda! Kaj kio pri Esparanto?
 
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