Which is why here in Sweden they still use pre metric measurements
equivalent to feet (fot) yards (Aln) and inches (Tum) and the local narrow
guage railway 50 aln away from my flat has a gauge of three swedish
feet.... oh yes lumber can also be bought in pre metric sizes.
Well, having been brought up with both, and having bought all kinds of
things measured in both systems, and having lived through an incomplete
conversion to metric here in Canada, my considered conclusion is that
the old system is more consumer friendly. Why? Precisely because its
measures are based on the human body.
And human drinking capacity. Have you noticed that "standard" metric
drinks are sized very close to the old measures, with some rounding off
here and there? Eg, a half pint is 227ml - the standard soft drink in
Europe is now 250ml, which is about one tablespoon more.
There's also the convenience of estimating quantities that give us
results within a half unit or so. For a carpet, for example, a
centimetre is too small, and a metre too large, but a foot is just about
The usual argument in favour of the metric system is that it's
"rational", because all its units are related to each other by powers of
10.*** Well, so what? The hard fact is that most people never convert
units into each other -- they never need to do so. People need units
accident that in Austria when I were a lad sliced meat was bought by the
"Deka", ie the 10gm unit. It's rather small, being less than half an
ounce, but it's in the right range - a slice of ham weighed about a
Deka, depending how the butcher set the slicing machine. On a recent
trip to Austria I shopped at a farmer's market. I noticed that people
asked for "about 1/8 kilo" of cheese, etc, not for 125gm. Interesting, eh?
I have nothing against the metric system, I use it a lot, actually. But
I do get testy with people who believe that it's inherently superior to
other systems of measurement. It isn't. It's just different. The same
goes for the imperial system. Use either for what it's good for, and
ignore it otherwise.
My old physics professor said: "There are two mensuration systems: the
metric and the barbaric."
But to get back to the topic that started this amazingly long thread.
Us modelers use a large variety of sources for our models: kits, plans,
sometimes very old documentation (that may use the stone-furlong-fortnight
mensuration system.). Kits and plans come in an amazing variety of scales:
1:4, 1:5, 1:6, 1:8, 1:12, 1:16, 1:24, 1:25, 1:32, 1:35, 1:48, 1:50, 1:75,
1:96, 1:100, ...1:720 ..and probably a whole bunch more that I've missed.
The base may be either in feet and inches, or metric. Our materials,
today, are usually either metric or English or both. So, let's say I have
some small brass strips sized in inches, and I'm building a 1:75 scale model
with metric plans. I want to know in an instant if that strip is the size I
want...without dragging out a calculator, without having an RS-232 or other
cable winding itself like a cobra around my delicate model, without a
blue-tooth transmitter dragging my wrist down, and without having to go to
the other room to look at the computer screen because my shop is not a
healthy place for computers. I want to do that conversion in an instant.
Apply my caliper to the material and instantly read the scale dimension in
the proper units. The ultimate digital caliper for modelers would do just
Imperial measure has roots probably back to Pharaohic Egypt as well as
Babylon and ancient India. Many
of these measures were designed mathematically to have a large number of
even dividers. I'm not sure
about measures like the cubit, but I'd imagine that in use it was divided
and multiplied by values that gave a
lot of even divisors also.
Certainly our clock, with its hours, minutes, and seconds, has these
When ancient engineers worked on early gearing, they needed to be able to
use evenly divided circles.
In fact, they needed to use circles that could be divided using only the
classical dividers and straightedge.
This, rather than a barleycorn, someone's foot, or someone's arm, were the
justifications for the
Imperial measurement systems.
On the other hand, 10 as a basis is obviously anthromorphic - and not very
useful; try using a compass
and straightedge and dividing a circle into ten equal parts. Now do the same
thing for twelve parts.
On topic though, what is needed is digital calipers and digital micrometers
more than just selection of metric or imperial. They also need to allow
scaling factors. This would allow the readout to be given in any arbitrary
More apt to be both useful and achievable would be a set of gauges for
widths, and diameters. Along with this would be gauges for screws and bolt
although they would be much harder to produce.
By the way, what is the 1:75 scale model a model of? If it is early 20th
power or rolling stock, it would most likely be a model of an American made
Which means that the original was built in Imperial units. So, all of the
you have are a conversion to begin with. It's one thing if the manufacturer
dimensions in 1:75th scale, but if they list the prototype dimensions in
Metric, I'd say
they have created a real problem. On the other hand, if they list only scale
that is needed is a Metric reading caliper or micrometer.
"Bob Engelhardt" wrote: (clip) Do you know how it determines the
denominator when it's not an exact
The most logical thing would be for it to read in the fractions that it is
set up to resolve, and jump from one to the next, without trying to get
exact matches to the other scales. If you are reading in 1/128's of an
inch, for example, you are interested in the closest value to the actual
diameter--not the closest value to a number in some other scale.
What I meant in my example was: If you measured something that was
actually 15mm, but wanted it to read in fractions, how would it display?
I would hope that it wouldn't display in some fixed denominator, e.g.,
128 ths. Because measuring something to be 96/128 is not nearly as
useful as knowing it's 3/4. What about 80/128, now what is that? Let's
see ... divide both by 16 gives 5/8. OK, 5/8 it is. I'd want one that
would say 5/8, not 80/128. Can you imagine a list of material described
this way: "2 pcs 80/128 brass, 4 72/128 long".
I think I'll stick to my old manual type ones , I've had them for many
years along with my micrometers and they served me well in my work ,now
in my hobby.
I have a few scale calculators that work well .
"I'm not young enough to know everything."
And I suppose you would want it to print the data, too. What you
request would be fine for single readings. Unless the instrument has a
useful memory, you will have to write them down. Gee, just like the old
Low cost have a data port . But they need a 2nd memory
so u can go back and forth ABS and REL .
Im doin ARM7 mcu , but software is Luddite , so
no one is having fun . Ill give some free s/w soon ,
end all that .
My s/w wont use English Text to program.
Have you ever heard of anyone progarmming
a computer at high level , with no text input ?
I will be the first , Anyone , anywhere of
any nationality will be able to program it in
minutes , without a manual ..
BTW Stay away from VXB bearing . I got ripped .
$500 of 6002 and 6003 , the cage was dragging ,
kinda like that HF mill-drill that used tapered rollers
and lower roller cage was dragging on the housing !
So there are calipers with digital outputs? That gives me an idea: what
if a guy were to connect such a caliper to a small custom-made unit,
instead of a computer, that would display the size in whatever scale
I probably have enough skills programming a little bitty CPU (like the
Ubicom [formerly Scenix] SX-28) to make something like this. Sounds like
a fun project. Could fit in a small box, easy to more around with you.
Anyone know the type of interface these calipers use? USB? Serial?
Just as McDonald's is where you go when you're hungry but don't really
care about the quality of your food, Wikipedia is where you go when
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