In article , huntres23
@optonline.net says...

On Sun, 4 Mar 2012 17:38:32 -0500, "J. Clarke"
wrote:

In article , huntres23
says...

On Fri, 27 Jan 2012 16:42:21 -0800, "PrecisionmachinisT"
wrote:


"Ed Huntress" wrote in message ...
On Fri, 27 Jan 2012 23:29:46 +0000 (UTC), "Kelly D. Grills"
wrote:

* Just Me :
If the US would get of it's arse and switch to metric like the rest
of the world it wouldn't be such a big thing,it's going to have to
eventually so why not just do it.

Yeah, that's what they told us in high school shop class... in 1974.

Physics class, too, in 1965. And science class, in 1960...

The drumbeat goes on. d8-)


The ability to deal with whatever comes your way is handy, most things these days typically having been designed by Frankenstein or relative if you catch my drift.

g This has been one of my hobby horses for decades. I had to write
an article about it in the late '70s, so I went first to Caterpillar.
"What are you talking about?" they asked. "We're 100% metric."

Within a few years, most of the automobile industry was, too. Now
they're 100% metric, as well. So is all of US science, medicine, and
most of our other volume manufacturers.

I went to NIST. You'd think they'd be the biggest pro-metric folks on
the continent. Their reaction? Officially, "Its a bad thing to be
using inch measures." Unofficially, "Eh," accompanied by a shrug.

The conclusion is this: Where it matters, we're already 100% metric.
Where it doesn't, we're *still* mostly converted to metric. Most of
our use of inch/pound etc. ("customary units") is in consumer products
for lengths and volumes. It really doesn't matter a whit for them.
They aren't converting erg-seconds to femtowatts.

Job shops still get a mess of both measures, and they're the ones who
have a right to be ****ed off about it. Otherwise, it's not really a
problem. And keep in mind that our dimensions for length are in
decimal units for most technical things, anyway. It matters little
whether you start with a meter or with an inch if you do that, as long
as you don't have to keep converting. And with computer controls, you
just push a button even for that.

For those reasons, it's mostly a tempest in a teapot. There are some
good reasons to go all-metric, but there are few people who would even
notice.

We're "metric" for certain values of "metric". Calling a 7/16 bolt
"11.11mm" on the drawing it "metric" but it doesn't really do anything
for clarity.

Right. You may recall that the US automobile industry spent a couple
of years diddling with what they called "soft metrics." They were inch
values converted to metric, and they produced results like your
example.

Here's a fairly current drafting manual on the subject:

"2.2 Soft Metric ? Soft metric conversion drawings maintain the
original inch design but are converted to express
the units of measurement in the SI metric language, including
dimensioning and tolerancing in millimeters (mm).
Soft conversion drawings are used when expensive tooling and
production equipment cannot be immediately
replaced or when the transition period to metric is limited. Soft
metric may also include using metric fasteners."

http://www.draftingzone.com/contentl...pdf&fileType=P

It's been decades since it happened in the car business, but my
recollection is that they used inch fasteners, expressed in metric
conversions, at the time.

But in that industry, as well as many others, they've long since
converted to "hard" metrics.

The brake lines on my '97 Jeep have metric fittings on one end and
english on the other. Some fasteners are metric, others aren't. As of
'97, all fasteners on Chrysler products clearly were not metric
standard.