45.836
Figure 3-49.-Lettering vertical numerals.
S and &. The upper and lower portions of S
are ellipses, the upper slightly smaller than the
lower. The ampersand (&) is basically similar
despite a greater difference in the sizes of the
ellipses.
Numerals and Fractions
The need for extreme care in drawing
numerals cannot be overstressed, particularly in
the preparation of construction drawings in which
a poorly drawn numeral can cause costly errors
and delays.
Numerals are drawn using the same size guide-
lines as the capital letters on a drawing. Vertical
guidelines are spaced at random. Numerals should
not be made so small or be crowded so closely
as to impair their legibility.
In figure 3-49 the vertical stroke of the
numeral 4 is placed two units from the
right side. The horizontal bar is one quarter
the height of the number above the base line.
Note that the closed curves of 0, 6, and 9
are elliptical, not circular. The 6 is an inverted
9. The 8 is composed of two ellipses tangent
slightly above the center point. The top
ellipse also is narrower. The 3 is the same as
the 8 with the left portions of the loops
cut off.
elliptical
the 5 is
The curved lines of 2 follow the
contours of 8. The top portion of
slightly narrower than the bottom.
Figure 3-50.-Vertical fractions.
The bottom ellipse is two thirds of the height
of the figure from the base line.
The division bar between the numerator and
denominator of the fractions is always drawn
parallel to the guidelines, as shown in figure 3-50.
The complete height of a fraction is twice that of
a whole number. The division bar is centered
midway between the base line and cap line. The
top guideline of the numerator and the bottom
guideline of the denominator are spaced a full
number height from the division bar. The
numbers composing a fraction are three quarters
of the height of a full number. The clear space
on either side of the division bar is one quarter
of a full number. Numbers in a fraction are
centered about a vertical guideline that cuts the
fraction bar in half.
Lowercase Letters
Lowercase letters are never used on construc-
tion drawings, although it is acceptable to use
them for notes on maps or similar drawings.
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