• Engineering 1182

College of Engineering

Engineering Education Innovation Center

Inclined Surfaces in Orthographic

Projection

Sections 11.02 -.03 of Text

• Engineering 1182

Objectives

• Understand how different types of

surfaces will appear in each viewing plane.

• Create orthographic projections of objects

with inclined surfaces.

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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.

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Inclined Surfaces

Edge view of

inclined surface

• 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.

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Inclined Surfaces: Example

CLICK

* Note that the size of the

inclined surface changes in

two views, but the shape

does not.

* Note that the edges of

the inclined surface

project orthographically

into the other two views

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Inclined Surfaces: An Alternative Method

The Miter Line

CLICK

Project Corner Edges,

Draw Lines.

45°

Draw MITER Line at 45°

Project Edges

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Recognizing Principal or Normal Surfaces,

Inclined Surfaces and Oblique Surfaces

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.

Principal Planes:

TOP, FRONT & RIGHT

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Inclined Surfaces in Orthographic Projections

• Use this time to practice making

orthographic projections from objects with

inclined surfaces.

• In class assignment