Orthographic Projection

1
Orthographic Projection
Auxiliary Views
2
Auxiliary View

• To accurately view the true dimensions of an
  inclined surface, one must create a view at 90
  degrees from that inclined face. This is
  referred to as an Auxiliary View. This allows us
  to view the surface in its true size and shape.

3
Primary Auxiliary View
In order to see a feature in its true size and
shape, we must look at it straight on or
perpendicular to the plane in which the feature
exists. Note that in this view (the auxiliary
view) the slotted hole is true size and shape.
Many times a feature on a part cannot be seen in
true size and shape. When this is the case we
use an auxiliary view.
4
Secondary Auxiliary View
Sometimes you may have a feature that is oblique
in all three views. This type of feature needs
two auxiliaries to obtain a perpendicular line
of sight on that surface.