Efter mange tanker skrev josephkk:
On Tue, 22 Jul 2014 08:58:44 +0100, "Gareth Magennis"
wrote:


No it converts to 24.507874 inches if you us the same maths notation.




The point is that the Imperial system commonly uses discrete steps that
are only accurate to those steps.

The metric system does not suffer this limitation.


Gareth.

Neither does the imperial system if you use a rule marked in tenths and
Micrometers are marked in 1/1000s or some such and not fractions which
were near enough for woodworkers in the past.

PS I am no fan of Imperial either in measurement or in Government but
we have to live with rest of the world and be tolerant of whatever
comes by. :-Z





Some time ago I was employed to install the audio wiring in a new build
recording studio.
In one room, I was astounded to find the carpenter had pencilled in the
width of one wall using a measurement of feet, inches, and so many 8ths of
an inch.

So he was only working to an accuracy of 16th of an inch, which is 1.58mm.
To me, this is completely unacceptable in a professional environment, and
the basis of my posts in this thread.


Please be more thoughtful about how quickly you judge. 1.6 mm is just
about best surface smoothness over a 3 to 5 meter range of a wall, not all
that shabby. If you think you can do better than skilled trades workers
just give a try some time.


My maternal grandfather was a machinist working lathes and making
cogwheels.
My paternal grandfather was a bricklayer.
They had very different views on accuracy.
Maternal grandfather could see "This shelf is 3mm lower on one side
than the other" from across the room
For paternal grandfather "accurate" was within the width of a joint
between bricks. :-)

--
Husk kørelys bagpå, hvis din bilfabrikant har taget den idiotiske
beslutning at undlade det.