1. Inclined Surfaces in Orthographic Projection
Sections of Text

2. Objectives
Understand how different types of surfaces will appear in each viewing plane.
Create orthographic projections of objects with inclined surfaces.

3. Surface Types
So far, we have created orthographic projections of objects made of only normal surfaces.
Now, we will look at inclined surfaces.
The table below list the basic characteristics of each surface type and how each appears in orthographic projections.

4. Inclined Surfaces
In orthographic projections, inclined surfaces are defined by the view in which they appear as an edge.
Notice how it appears as a surface in the other two views.
Edge view of inclined surface

5. Inclined Surfaces: Example
* Note that the edges of the inclined surface project orthographically into the other two views
* Note that the size of the inclined surface changes in two views, but the shape does not.
CLICK

6. Inclined Surfaces: An Alternative Method The Miter Line
45°
Draw MITER Line at 45°
Project Corner Edges,
Draw Lines.
Project Edges
CLICK

7. Recognizing Principal or Normal Surfaces, Inclined Surfaces and Oblique Surfaces
Principal Planes: TOP, FRONT & RIGHT
A PRINCIPAL SURFACE APPEARS IN ITS TRUE SHAPE IN ONE VIEW AND AS A LINE IN THE OTHER TWO VIEWS WHERE IT IS PERPENDICULAR TO THE OTHER TWO PRINCIPAL PLANES. .
AN INCLINE SURFACE APPEARS AS A LINE IN ONE VIEW AND IN ITS CHARACTERISTIC SHAPE IN THE OTHER TWO VIEWS WHERE IT IS ANGLED WITH RESPECT TO THE OTHER TWO PRINCIPAL PLANES.
AN OBLIQUE SURFACE APPEARS IN IT’S CHARACTERISTIC SHAPE IN ALL THREE VIEWS WHERE IT IS ANGLED TO THE OTHER THREE PRINCIPAL PLANES.

8. Inclined Surfaces in Orthographic Projections
Use this time to practice making orthographic projections from objects with inclined surfaces.
In class assignment