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Cook, George H. (ed.) / The Wisconsin engineer
Volume 40, Number 3 (December, 1935)

Jorgensen, Allen
Ford Motors adopt new measuring system,   pp. 58-59

Page 58

Ford Motors Adopt New
         Measuring Syjstem
                       ALLEN JORGENSEN, m'38
OF ALL the evils bequeathed to humanity by Usage
       and Tradition, few are as time consuming and
       clumsy as the English "system" of weights and
   The hue and cry for a simpler system has been heard,
and answered, by one of the world's foremost industrial-
ists-Henry Ford. While congressmen and scientists
wrangled with practical men on the advisability of mak-
ing a costly change to the metric system, Henry Ford's
men were busy adapting the old system of measuring to
efficient means. The result was the decimal system.
  It is considered the first departure from conventional
dimensioning practice. For countless ages man has re-
sorted to the use of fractional measurements. Engineers
and production men have been so firmly entrenched in
the use of "halves," "quarters," "eighths,"
etc. that im-
provement was considered impossible without the com-
plete change to the metric system.
  Why then was not the metric system adopted? Scientists
advocated the change while producers stood adamant to
their resolution that no such revolutionary step be taken.
  The builders of machinery that has made this the fore-
most industrial country can hardly be called ignoramuses,
and it seems likely that if the metric system had the ad-
vantages claimed by its advocates a good percentage of
progressive machine builders would have adopted it long
ago. If they had wanted it, compulsory legislation would
be necessary.
  Many there have been who argue that we lose foreign
trade because of our refusal to adopt and use the metric
system which is now in use in so many foreign countries.
Yet, 75 per cent of all manufactured articles are today
made under the English system of measuring. Even Japan,
although on the metric system by government decree, still
has railroad distances given in miles instead of kilometers.
It is obvious that producers in this country would also
defy governmental legislation and resort to the use of the
English system on the sly in preference to making the
expensive change-over.
  Americans have been accused of being too lazy to make
the conversions necessitated by a change in scale. A bit
of study would reveal that on the more intricate machines
such translation would be exceedingly difficult, and con-
sequently money consuming. Then, too, it must be borne
in mind that all maps, deeds, lands, and countless docu-
ments are now expressed in terms of feet and inches. A
change would be economically out of the question. It is
true that it would be a fine heritage to leave to our chil-
dren a system of measuring not based upon the size of
"three barley corns to an inch" - drought or no drought
-but the cost is prohibitive.
  To obviate such a revolutionary change and still to gain
efficiency, an adaptation of the old system seems to be the
only answer. It is an adaptation similar to the adoption of
decimal currency by the Hamiltonians as an escape from
the pestiferous arithmetic of pounds, shillings, and pence.
  Common fractions are out, and with them go the use-
lessly long decimal conversions. With the new system of
decimal fractions, it is no longer necessary to carry the
divisions of a fraction out to the sixth or seventh place in
order to gain a true number. For instance, 1/64 of an inch
when converted to decimal becomes 0.015625 of an inch;
whereas, 1/50 of an inch under the new system becomes
0.02 of an inch. This is illustrative of the simplicity of
conversion of the new system as compared to the old. It
reduces the possible error when adding long decimals in
shop and drafting room. Conversion tables need no longer
be the master of the mechanic and draftsman.
  Under the Ford system no cumbersome dimensions are
necessary. Every dimension is simply expressed and easily
read, and the chances for error are practically eliminated.
Where old parts must be replaced, it is a simple matter to
convert the old system to the new. For those who have
not become entirely proficient in thinking in "tenths," but
only in such cases, it was decided to simplify the decimals
resulting from converting the common fraction in the
manner indicated.
Com2non Fraction
Decimal of Existing
Comm 020 1Fraction
     1 /64
     15 /32
Ford Decimal
  The new system is complimentary to the micrometer
readings in that when a closer reading is required from
that gotten with the naked eye and scale, it is merely nec-
essary to affix the two final digit readings from the mi-
crometer to the size gotten with the scale. This is a good
deal simpler than adding it to an incongruous decimal
converted fraction.
  A primary requisite in the adoption of the Ford system
is the accompanying change of "thinking grooves." The
man on the job must be taught to think in terms of tenths
rather than sixteenths. Inasmuch as mechanics are famil-
iar to the use of the micrometer and resulting readings, in
thousandths, this is a simple matter.
  Whereas the old scale was calibrated in 1/64ths of an
inch, the new one is calibrated in 1/5Oths of an inch. The
scale can thus be read in hundredths of an inch by merely
The Wisconsin engineer
P.ige 58

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