Oblique Projection (PowerPoint)

					Oblique Projection


     Chapter 15
           Oblique Projections
• In oblique projections, the projectors are
  parallel to each other but are not
  perpendicular to the plane of projection
• One of the object’s principal faces is parallel to
  the plane of projection
Oblique Projections
            Cavalier Projection
• When the receding
  lines are true length,
  and the projectors
  are at 45 degrees to
  the plane of
  projection, the
  oblique drawing is
  called cavalier
  projection
            Cabinet Projection
• When the
  receding lines are
  drawn to half size,
  the drawing is
  known as a
  cabinet projection
   Cavalier and Cabinet
Projection of a 1 Unit Cube
        Offset Measurements
• Circles, circular arcs, and other curved
  surfaces are drawn using offset measurements
    Angles in Oblique Projection
• When an angle is specified in degrees in a
  receding plane, convert the angle into linear
  measurements to draw the angle in an oblique
  drawing
Angles in Oblique Projection
      Screw Threads in Oblique
• Partial circles spaced equally show symbolic
  thread pitch
        Oblique Dimensioning
• Oblique drawings are dimensioned in a similar
  fashion as isometric drawings
           Computer Graphics
• Using CAD, oblique drawings can be created
  by using snap increments and drawing
  similarly to drawing on grid paper
• If a complicated pictorial is needed however, it
  may be easier and more accurate to create a
  3D model
Engineering Text Example
Draw a cabinet oblique sketch
  for the piece of furniture.