58 Engineering Fundamentals
sketches are often the only noncomputerized
method of planning a design. Ideas are often
taken from the initial sketches, researched, and
then manipulated using computer software.
The sketching process follows four basic steps:
1. Visualize the solution.
2. Block out the solution.
3. Outline the solution
4. Detail the solution.
Visualize the Solution
First, the engineer visualizes the appearance
and the functionality of the object. The function-
ality, or the way the object works, is typically of
the most concern to an engineer. The engineer
begins by visualizing the operation of the object.
Usually, engineers see the object in three dimen-
sions, but they might also view the object from
the six different sides of the object. See Figure 4-4.
Block Out the Solution
Once the visualization of the object is devel-
oped, the engineer begins to block out rough shapes.
Sketching solutions usually requires a combina-
tion of boxes, cylinders, cones, and pyramids. With
knowledge of blocking out these shapes, engineers
are able to create most sketches. The engineer uses
light lines to represent the rough size and shape of
the object. These fi ne lines are used as guidelines to
create more detailed views of the object.
Isometric drawing methods make an object
appear three dimensional on a two-dimensional
object, such as paper or a computer screen.
Isometric drawings are used to give a real-world
appearance of an object by showing the front, top,
and side views, just as the eyes see the object.
Boxes are used to block out many shapes. To
create a box to draw a feature, the engineer fi rst
draws a vertical line as the front corner. Then
the engineer draws one line on each side of the
front corner. Then the engineer connects the lines
at the top and bottom using roughly a 30° angle.
The box is then completed by drawing two lines
parallel with the lines going to the front corner to
create the top of the box. See Figure 4-5.
Cylinders are often used to create a rough
block for an object. See Figure 4-6 to draw a cylin-
der. Drawn an isometric square containing an
ellipse, or an isometric circle. Draw a duplicate
square above the fi rst square by drawing verti-
cal lines of equal lengths from each corner of the
original square and by connecting the points. An
ellipse is drawn inside the new square.
Cones and pyramids are drawn using a box.
An X is drawn on the top of the box to deter-
mine the center. The center point of the X will
be the top point of the cylinder or cone. Lines
are drawn from the top center point to each
bottom corner of the box to create a pyramid.
Figure 4-4.
Engineers view objects in three dimensions, but they may also look at each of the six sides of an object individually.
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