July 01, 2014

Some jargon and a triumph of capitalism

Jargon can be obscurantist at times but can also be useful.  Most trades and occupations have their own jargon as a quick means of communication.  I have been involved with quite a few trades and occupations in my life so am pretty jargon-loaded.  I try to keep it within its own context, however.

An example of jargon occurred recently when I saw a carpenter about to throw out something that had some bolts and nuts in it.  I checked that he really was throwing the nut out and he said he was.  I then unscrewed the nut, took one second's look at it and said: "That's a three eight whitworth".  In reply he agreed that the nut was worth keeping.

So what had I said?  What had my bit of jargon conveyed?  To answer that fully you need to know about Joe Whitworth.  Whitworth was an engineer in mid-19th century Britain.  One of the things he did was make bolts and nuts (he made a good sniper rifle too).  And his bolts and nuts were very good. People found them to be stronger and more accurate. So after a while people wanted to buy Whitworth bolts and nuts only.  So all makers of bolts and nuts had to convert to "Whitworth standard" if they wanted to stay in the business.  And they did.  No government devised the Whitworth standard and no government made people use it but the standard became fixed and a fixed standard was found very useful.  And until other nations caught on it gave British machine-makers an advantage. The French were amazed at how quickly Britain could build gunboats for the Crimean war, for instance.

And America caught on too.  The American "National Coarse" standard is only a slightly modified version of the Whitworth specifications.  You can usually use NC and Whitworth bolts and nuts interchangeably (Yes.  I know about the pesky half-inch size).

But then it gets even more interesting.  Because a Whitworth thread is coarse it is very strong but it is also a bit wobbly for some precision purposes.  So a fine thread was also needed.  Alas!  Mr Whitworth did not bother with that.  So it fell to others to devise fine threads.  And by that time the clammy hand of government was felt.  Governments took it upon themselves to set the standards.  And in true government form they messed it up.  The British fine standard (BSF) and the American fine standard (SAE) are quite different.  No interchangeability any more.  A big part of the advantage of standardizion was lost.

So, to get back to my original story, I was telling the tradesman that the thread in the nut was coarse (Whitworth standard) and that the diameter of the bolt taken by the nut was three eighths of an inch.  I could tell that measurement by eye, as most people in the engineering trades could.

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