a)        Define an isometric cube.
See textbook pages 652-655

b)        Identify isometric axes and non-isometric axes. 

Non-Isometric Lines are any lines that are not parallel to the Isometric Axes

c)        Demonstrate how to apply angles in isometric. 

d)        Demonstrate how to draw circles in isometric with: 

See textbook pages 656-657

            *         the compass approximation method

           *         the use of isometric templates

           *         ellipses in CAD 

In AutoCAD, isometric drawing can be done in the SNAP command.  Once in the SNAP command, choose the Style/Isometric option. This will set your grid and snap to the isometric format. You can toggle between iso-planes (top, left-side, right-side) by pressing F5.

If you use the ELLIPSE command while in isometric mode, you will have a new option; Isocircle. This will allow you to draw an isometric ellipse by locating the center and giving the radius or diameter.

e)        Demonstrate how to plot curves on isometric planes.   

f)        Lettering in isometric.  

Lettering in isometric projection must be parallel to the 2 axes (vertical and horizontal) that the lettering is following.

To letter in CAD in isometric you must create 2 styles with the following obliquing angles:

ISO1 - obliquing angle 330 degrees
ISO2 - obliquing angle 30 degrees

Then place the lettering rotated at the angles shown below:

*More reading material

a)   Define an oblique cube

An oblique cube is defined by its angle and direction.
The plane in which the view is not distorted is called the "Picture Plane"

b)   Determine when an oblique projection is preferable
    over isometric projection (and vice-versa) and why.

Oblique projection is preferable over isometric projection when all the curves or circles are in the same plane (which will be chosen as the picture plane).

            Oblique is more preferable in this case since the circle or arc can be drawn as a true radius rather than an ellipse. 

             If curves are present in two or more of the three planes (top, right-side, left-side) then isometric projection is preferable. Isometric ellipses are easier to construct and more natural looking than oblique ellipses.

c)   Circles and arcs in oblique projection.
Circles and arcs should be drawn in the orientation that they show
as a true circle or arc, not an ellipse





d)   Identify and establish oblique axes.

Drawing axes should be established to reveal the most amount of 
information in the un-distorted Picture Plane (unless circles or arcs are present, in which case they should go in the Picture Plane)

e)   Understand the definition of Cabinet and Cavalier Projection.
 

          a)       Briefly explain the differences between the isometric and

                    oblique drawings and perspective.

            A perspective pictorial drawing is more useful as a visualization aid than as a construction drawing. 
With the use of vanishing points, the perspective drawing looks more like objects we see in real life, but it is difficult to dimension.

b)           Define:

                          *picture plane
                          *horizon plane
                          *ground plane
                          *station point
                          *vanishing point

c)       Demonstrate the effect of station point relative to picture plane.

As the station point moves farther from the picture plane, the vanishing points become farther apart and the lines vanish less abruptly. 

         d)       Demonstrate the effect of horizon plane relative to top of object.

As the horizon moves above or below the object, we see the top differently.

   e)       Plot circles and curves in perspective

Perspective Layout: