Figure 1-7.Orthographic and isometric drawings.
Once you understand the drawing in figure 1-7, the
same idea can be applied to the drawing of the shape of
a room, as shown in figures 1-8 and 1-9.
DRAWING AN ISOMETRIC VIEW
To determine the pipe layout, you can draw the
dimensions of a room in several ways. Some
Engineering Aids suggest that the lines of the room be
drawn with fine, light lines, and the pipe diagram with
heavy, dark lines to give the effect of a transparent
room you can see into, as shown in figure 1-10. This
method requires drafting room equipment and is
difficult in field sketching.
Another means of visualizing the pipe layout is to
section or remove from the drawing those parts in
front of what is important to show. The usual section in
Figure 1-8.Isometric drawing of a room.
Figure 1-9.Isometric drawing of a room and drainage pipe.
a plumbing pipe layout leaves the ceiling and two walls
out of the drawing, as shown in view C of figure 1-10.
A third method is simpler in that the room is shown
only as a partial floor plan view, as shown in view D,
figure 1-10. The walls are omitted from the drawing
entirely. It is understood that the walls are to be there,
but they are left out so the piping diagram is shown
without unnecessary details.
To lay out a 45-degree angle in an isometric
drawing, draw a square and lay out the 45-degree
angle, as shown in view A, figure 1-11. Now look at
view B and you will see a block with a 45-degree
chamfer. The chamfer is located by measuring equal
distances from the corner that would ordinarily be