[sdiy] Metric OT rant

[Echophazer at aol.com]

I've thought about this subject more than a few times and came up with this 
theory of why the US still uses Imperial. Mind you this is from information 
I've gathered and not any actual fact that I can refer you to.

Prior to W.W.II the US was using Imperial but there was talk of moving over 
to Metric in industry.  Not long after this W.W.II came about and then the 
major US involvement after Pearl Harbor. The government poured massive 
amounts of money into building and tooling up factories for the war effort. 
The military specified that the engines and vehicles be made in inches and 
not metric in order to throw off efforts of the opposition reverse 
engineering or repairing our equipment. (The biggest pain in the butt for 
them would be that our bolts and other threaded fasteners were all in inch.)

So the war ends and the government knows what historically happens.... 
Economic recession. 
To help combat this, all the machines were sold off for insanely low prices. 
Automobile and other manufacturers took advantage of this. Factories opened 
up everywhere and provided new jobs for people to earn a living on. Also so 
they can spend that new income on the very products that were being made. 
I work at a plant that was build by Buick to make engines for the B-24 
bombers back in the 40's. After the war the plant was sold to a truck and 
farm implement manufacturer. From the stories I've been told the whole 
building (which is huge) was sold for a few million. All the lathes, mills, 
drill presses, etc....... Only cost a dollar each. These days all the 
machining of engine parts is done on automatic lines but a few of these old 
Naval ordinance machines are still around.
As new manufacturing lines are put in the individual stations will have a CNC 
interface. With CNC all that is needed to convert inches to mm is a push of 
the button. It's my personal feeling that because of CNC in big industry the 
inch system will gradually fade out of the scene. It will take a long time 
but where we are at right now is the beginning of a crossover point.

All of our blueprints are in inches. Most all of the bolts used on the 
engines are in metric (some screw in sensors and pipe plugs are in inch).  

I'm an apprentice metrologist find this personally to be an interesting 
topic. The things I've written here are based on questions I've asked and not 
facts out of a book so take it with a grain of salt. 

Peter B.