Microsoft Word - lecnote_fm_engineering drawing

Figure 7.10 Orthographic projection of horizontal lines

E. Profile Lines
A profile line is parallel to the profile plane and shows as true
length in the profile view. The frontal and horizontal view of a
profile line always shows the line as a point view or
foreshortened, in either case the line is parallel to the profile
plane. Vertical lines are both profile and frontal lines since
they appear true length in the frontal and profile views and as
a point in the horizontal view. Where a profile line appears as
a point in the front view, the line is both a frontal and profile
line.