A glimmer of hope

[mklotz]

A recent post on HSM had the following quote...

"The use of gauge number is discouraged as being an archaic term of limited usefulness not having general agreement on meaning." (Specification ASTM A480-10a)

I found it immensely satisfying to see that the folks who arbitrate the quagmire of nomenclature systems have finally had the good sense to say what I've been preaching for many years - the only sensible way to label things is by their sizes as measured using a decimal measurement system.

I don't expect their recommendation to have any effect whatsoever on the dinosaurs who still treasure the inferial nonsense but it's nice to know that a glimmer of intelligence is peeking through the curtain.

[Frank S]

I'm afraid that peeking may be about all though. at least until manufactures of materials normally listed in gauge sizes adopt a decimal measurement system

[volodar]

"I'm afraid that peeking may be about all though. at least until manufactures of materials normally listed in gauge sizes adopt a decimal measurement system"

To change, they'd have to be "encouraged" somehow. I don't see these dinosaurs changing on their own, unless their bottom line finally suffers. Not likely in my lifetime - at seventy eight.

[mklotz]

The only way to fix the problem is to fully adopt the metric system, teach only that in the schools, and wait for all the dinosaurs to die out.

Nomenclature systems, of which this is an example, are not part of measurement systems but all the countries that use the metric system use sensible, size-based nomenclatures for things like sheet, wire, drills and taps. Adopting the metric system, a good thing in its own right, would naturally lead to use of these sensible nomenclatures once the old Luddites are gone.

[nickyd]

Why is the 'Micron' still in common use?
This was internationally changed to 'Micrometer' in 1969.

[mklotz]

Why is the 'Micron' still in common use?
This was internationally changed to 'Micrometer' in 1969.

The term "micron" isn't the only survivor. The medical community still uses "centimeter" as do many archaeologists. The metric system has numerous derived units, e.g. Newton = 1 kg-m/sec^2. As long as the unit is simply related to the primary units such derived units are acceptable. If we consider "micron" (= 1E-6 m) to be a derived unit, then all is well.

I think the arbiters of the metric system took a step backward when they dismissed such terms as centimeter and decimeter. Why is centi+meter conceptually different from milli+meter? So-called engineering unit steps of 1E3 aren't always convenient in the real world.

A minor quibble..

I don't think micron or micrometer should be capitalized. I believe the rule is that if the multiplier is less than unity it's not capitalized, if greater it is. Thus everything from "deci" to "atto" would not be capitalized and everything from "deca" to "exa" would be. The exceptions are the units named for an individual which are always capitalized. Thus the following forms

micron, millimeter, centimeter, milliliter, nanosecond
Kilometer, Megameter
Newton, Ampere, Pascal, Weber, Tesla

I'm not certain of the rule for applying prefixes to units named for people. I've seen both "GigaPascal" and "Gigapascal" but the abbreviation is usually "GPa" which implies that "GigaPascal" would be a correct spelling.

[tonyfoale]

Why is the 'Micron' still in common use?
This was internationally changed to 'Micrometer' in 1969.

i use it because it is easy to say and easier to write.

[mklotz]

i use it because it is easy to say and easier to write.

Also, "micrometer" used as a dimension in a machine shop setting can be confusing given that the primary tool in that venue has the same name.

One has to be careful with "mil" though since it's one of the common terms for milliradians. an SI unit...

https://en.wikipedia.org/wiki/Milliradian

Also the artillery setters use it as an angular measure. However, to maintain the spirit of inferial confusion, they've "rounded" the 6283... milliradians in a circle to 6400. I suppose the (admittedly slight) error so induced is compensated with more explosive shells.

[bill_h]

Australia has been miles ahead since it went metric.........

[MiTasol]

Also, "micrometer" used as a dimension in a machine shop setting can be confusing given that the primary tool in that venue has the same name.

But ONLY in the USA where some clown/committee with the power to do so in a fit of petty bastardry (or just to prove he/they had POWER) decided to misspell all metric measurements and did not have the brains to realize that the proper spelling of metre and meter automatically indicates the nature of the subject - metre for a measurement and meter for a measuring instrument.

Obviously the same clown/committee decided that the proper spelling of Aluminium (again as used in every country except the USA) was another way to deliberately create confusion and prove how powerful he/it was.

On the other hand when it comes to total METRIC stupidity then Australia takes the cake.

The first formal thread system invented was the British Whitworth system and was a great leap forward for mass production and ease of repair.

Early on the Americans also used Whitworth but soon realized that the 47 degree thread angle was not as strong as a 60 degree thread angle and created the American National Course (ANC) threads using the British TPI for most threads but with a 60 degree angle. They also recognized that the British head sizing sucked and fixed that problem.

During WW2, with lend lease, hardware interchangeability became a massive problem and the British and Americans jointly decided to address the problem with a new thread combining all the best features of both the Whitworth and ANC systems (and the related ANF and BSF systems) and created the Unified threads in 1947. Both countries transitioned as quickly as possible.

In November 1946 (71 years ago) the Brits classified Whitworth as Inactive for new design.

By 1952 Whitworth had disappeared from the vast majority of British mass produced products.

Sixty five years later in Australia Whitworth is still the preferred thread for many people and industries and small Unified hardware such as 8-32 and 10-32 is extremely hard to find in shops. Using Whitworth in an export item is a great way to destroy an export market as anyone outside of Australia will instantly recognize because no-one outside Australia has Whitworth hardware and tools.

In 1947 Australia signed the Metre Convention making metric units legal for use in Australia, and in 1970 passed the Metric Conversion Act with the aim of making the metric system the sole system of legal measurements in Australia.

By 1974 every school in Australia was teaching metric only. This means everyone over the age of 49 was schooled exclusively in metric and those as old as 61 received some schooling in metric. Early on it was illegal to sell goods in inferial (a great word Marv) but now it is legal to use both and many companies owned or managed by troglodytes have gone backward to inferial. The next time I am in any of several large clothing shops I shall photograph a typical trouser size label INCHES in big letters and cm in a much smaller font. I do not shop in those stores any more. And no, these are house brand products, not name brand products imported from the US or UK.

But getting back to threads and other steel products.

Australia loves Whitworth so much that they have recently introduced the 13mm bolt. When you measure it up it is 100% a 1/2 inch Whitworth bolt. No other country has a 13mm bolt as a common standard, let alone one that is a 100% bulls**t size.

When Australia started to manufacture Metric bolts they decided to use the head sizes of the nearest Whitworth size bolt.

When you buy an ISO standard tool set you do not get, as an example, an 18mm spanner because an 18mm tool is not used for any International Standard metric bolt.

In Australia you must buy the 18mm spanners and sockets because Australia, unlike the real world, uses the 18 head size. Naturally when Australia exports "metric" goods that means that when the customer goes to assemble or maintain or repair the product he/she does not have the right tools in their tool kit. Another great way to destroy an export market as anyone outside of Australia will again recognize.

And then we get to tubing - I will cover that in a few days time but the Australian tube diameters are, like Whitworth, from an archaic British measurement system. I have purchased REAL metric tubing from the US for several projects recently because it is not available here. Another great way to destroy an export market.