Quite simply, and I speak as someone who has spent many years in the
construction industry, DO NOT USE DECIMALS! Decimal points get lost as
construction drawings become soiled with dirt and concrete splatters, so
that 12.3 cm can all too easily be read as 123 cm [1.23 m]. And when
carpenters, plumber, electricians, etc read out a dimension to their
colleague at the other end of a tape measure, 123 cm can all too easily be
misheard/mis-spoken as 123 mm (never mind all the extra words involved).
When you stick to JUST mm, then there is no confusion, no decimals, no
mixing of units - '1234' means ONLY 1234 mm [1.234 m], nothing else. I just
cannot see your reluctance to accept that! Just look at your example of
1523.2 cm - you have to THINK what that means. It is of course 15 232 mm,
which is how it would be measured on site (and I nearly puy the thousands
separator in the wrong place there myself, showing how errors can happen so
easily when dealing with cm on site) - but it is also 15.232 m . Notice how
in converting from mm to meters (IN YOUR MIND ONLY, not in measuring or
writing), you simply replace the space (or comma, if one is used as the
thousands separator) with a decimal point. But like I said, that is only in
your mind, no decimals in the written numbers. Introduce the cm and that
all gets screwed up - and for what advantage? NONE!
For industry, including the construction industry, no matter how large the
dimension, it's ONLY mm - that is accepted, proven to work, and is the
standard. That will NOT change, and there is no point in even thinking
about changing it.
Outside of industry, it is a different matter. Centimeters CAN be very
useful, especially when calculating small areas and volumes, where the mm
results in some very large numbers and the meter some very small ones. But
that is quite a different matter. Pat N may or may not agree with that -
for me I am happy with cm in casual and colloquial usage, but NEVER EVER
when working professionally.
John F-L
----- Original Message -----
From: <a-bruie...@lycos.com>
To: "U.S. Metric Association" <usma@colostate.edu>
Sent: Tuesday, December 14, 2010 10:39 AM
Subject: [USMA:49196] Re: centimetre or millimetre
I love how Pat repeats himself but does not explain why is more expensive,
tortured and fraught going centimeters than going millimeters. And yes I
have read your MetricMatters, it still does not make make sense to me.
1523.2 cm 15.25 mm 0.5 mm
'Metrication
If you choose to use centimetres for a metrication upgrade you will find
that the process is expensive, tortured, fraught with difficulty, and
painfully, painfully, slow. I mostly base this observation on my personal
experiences with the building industries in Australia and in the
Australian textile industry but I have also been able to observe many
other industries in several nations. You might recall that I worked with
the Australian building industry for close to 15 years, and with the
Australian textile industry for about 10 years.'
Id put my money on the sun and solar energy. What a source of power! I
hope we dont have to wait til oil and coal run out before we tackle that.
I wish I had a few more years left. -- Thomas Edison♽☯♑
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