As everyone on this list knows, I'm a strong supporter of metrication. But I
don't think it helps us to deny real problems and sweep them under the rug,
or to dismiss the legitimate complaints of people in the construction
business. Builders are not all dimwitted, reactionary clods. Most are quick
to adopt any shortcuts that save time, because construction is labor
intensive and time is money. Interspersed below are my responses to Marcus'
queries and comments in USMA 8746:
> Do you or have you ever had a chance to follow these guys'
> work *in the field*, Dennis?
Yes, I worked in a variety of construction trades for 20 years and my father
was a contractor for 60 years.
> Are you saying that saying 5'6" would be easier than, say, 1500 mm???
Yes. "Five-six" (two syllables) is twice as easy to say as "fifteen hundred"
(4 syllables) and three times easier than "one thousand five hundred" (6
syllables). Workers would write this as 5-6, which is easier to write than
1500.
> How can "dual" names ever be simpler than single ones???
See above. I agree that foot-inch conversion is awkward, but in practice
workers make measurements in cumulative inches more often than they do in
feet-inches. In any event, calculation is rarely required, since the tape
has dual scales. Workers use whichever scale is most convenient.
> I don't see any shortcomings
> whatsoever with regards to metric "names", especially when we're
> dealing with *hard* metric values.
Hard metric products aren't available. That's the problem. But even if they
were, names would generally be 2 to 4 times longer (more syllables) than the
corresponding wombat names (not counting the unit, which is unexpressed in
either case).
> "Easier to read"??? I don't think so... But if one uses a pure tape, in
> either system, I can't see why they'd manufacture bigger fonts
> for ifp as compared to its metric equivalent.
On an inch-foot tape, the size of the numbers is limited only by the width
of the blade, whereas on a metric tape it is limited by the narrow (1 cm)
spacing between the numbers, regardless of the blade width. Therefore, the
numbers on a wombat tape are much wider, bolder, more open, and easier to
read than the condensed, narrowed, lighter face numbers on a metric tape of
the same size--even thought the wombat tape has two number scales and the
metric tape only one. The problem is magnified by the fact that most of the
wombat numbers are 1 or 2 digits, while most of the metric numbers are 3
digits (on a centimeter tape). On a millimeter tape (4 digits required), the
numbers are even smaller and you have to truncate most of them, dropping off
the first 2 digits for the 10 mm interval marks. You can only squeeze in the
full 4 digits every 100 mm. So if you compare a standard 1" (25 mm)
inch-foot tape side by side with an otherwise identical all-metric tape, you
will see that the numbers on the former can be read two to four times
farther away. For people who need glasses to read the metric tape (but not
the wombat tape), the difference can be a big aggravation. It means that,
using a metric tape, you have to put your glasses on and off every time you
make a measurement.
> Besides what advantage they may have in font size is largely
> overcome by its disadvantage for reading, period! As reading
> fractions of 2 in tapes is much more difficult than reading
> decimals, no matter how skilfull one is in ifp.
Fractions are certainly more difficult to write and to calculate with. But
the fraction marks are farther apart than the millimeter marks and are also
distinguished by different length ticks. So many people would argue that
they are physically easier to discriminate than the millimeters, and not
really difficult to read once you have learned the pattern. But there are no
fractions in modular sizes, the dimensions on architectural plans are always
in whole inches, and even in custom fitting builders rarely measure closer
than halves or quarters, so fractions are not really the big disadvantage we
like to claim.
> But the solution is quite simple, stop labeling these
> things in ifp, period! Forget about 2'4 3/4", etc. Just give me
> 647 mm, whatever value may come and I'll handle it!!!
There are no wombat products with awkward dimensions such as 2'4 3/4". They
are all nice round numbers.
> I don't care if I'm dealing with "soft metric" values. I can beat any ifp
deadbeat
> in this game, even no matter how "user friendly" these numbers in
> ifp may turn out to be, and that's a fact!
No you can't, Marcus, and that's precisely why builders are so bitter about
metrication. Suppose you have to lay out the spacing for standard 16"
concrete blocks, or studs placed three to a 48" plywood sheet. Which is
easier, marking every 16" (no thinking required, since the tape has a
special mark every 16"), or measuring off multiples of 406.4 mm? Can you
instantly multiply by 406.4 in your head? Can you remember all the multiples
of 406.4 up to 20 000 or 30 000? I can't. And no, you can't round that off
to 406 mm because the 0.4 mm would soon accumulate to a significant error
and the pieces would be too tight to fit.
> One does NOT need to do conversions back and forth...., no conversion
would be necessary AT ALL if ifp parts
> were stated in metric to begin with. That's what happens in
> metric countries that sometimes are forced to deal with some ifp
> components. They simply ignore for instance that a pipe is 2",
> they just take it as 50.8 mm and use it as is, like this.
I'm sorry, but if you're doing a "metric" building with wombat modular
parts, you DO need to do conversions--constantly. First the building is
designed in wombat so the parts will fit. Then all the dimensions are
converted to metric for the blueprints. Then on the job, they are all
converted back to wombat, for the reasons described above. This inefficient,
costly, and dumb, and builders know it.
Pipe is not a modular part, so is not an issue. And 2" pipe is called 50 mm
pipe, not 50.8 mm. The actual dimensions vary from 46 to 52 mm, depending on
the type of pipe, so 50.8 mm is falsely precise. Pipe size is a name, not
something that workers physically measure. But even in metric countries,
people often call it "two inch" (2 syllables) because that's 3 times shorter
and easier than "fifty millimeters" (6 syllables).
It's important to understand how measurements are used on the job. In most
trades, the vast majority of measurements consist of the following
activities:
(1) Naming products by their nominal size (no physical measuring involved)
(2) Measuring off a standard spacing for modular products (studs, rafters,
block courses, etc.). These are all marked on an inch-foot tape, so no
thinking or calculating is required.
(3) For custom (non-modular) fits of large pieces, one worker measures the
dimension and calls it out to the other, who makes the same measurement on
the piece, then cuts it and tosses it to the first worker. This saves
unnecessary walking back and forth or scrambling up and down ladders.
(4) For small pieces and very precise fitting (e.g., moldings), done by a
single worker, the cut is often measured directly on the piece (no units or
measuring with a tape are involved).
> If you followed my exchanges with that Mr. Naeyaert from Michigan, for
example, you
> would have seen that attitude is unfortunately everything in this
> business.
I read the exchanges very carefully. Naeyaert said that,
"Operating with a dual measurement system neither enhances quality
nor is it more efficient than a single measurement system. The vast majority
of the state's construction industry remains English,
with no plans to convert -- therefore true efficiency (and reduced errors
and enhanced quality) require that we all use a single measurement system
(English)."
This is true and quite logical. He gave more details, also true:
"...the rest of the construction industry, equipment manufacturers,
subcontractors, suppliers and the state's local road agencies continued to
use English measurements. Michigan's highway construction industry has been
forced to work with dual measurement systems where back-and-forth
conversions from English to metrics occur each time we plan, estimate, bid,
build and bill a project. This is cumbersome, inefficient, mistake-prone,
costly, and completely unnecessary. Throughout the past year MRBA has been
discussing the challenges, inefficiencies and annual financial costs to
taxpayers of maintaining a dual measurement system in the state. In the end,
Michigan's taxpayers are footing the bill for the direct (materials &
equipment) and indirect (loss of productivity & efficiency) costs associated
with maintaining a dual measurement system, and all without any tangible
value or return. MRBA's initial analysis demonstrates that Michigan
taxpayers are paying at least $7.4 million per year to continue with a dual
measurement system."
It sounds from his comments as though Naeyaert was ambivalent about
metrication when it started, or even supported it. But it gave them so many
headaches that they gave up on it. And now that you have railed against him,
he is so pissed off that he is vehemently against it.
