lecture 18 sketching 2015

Foundations of EngineeringENGR 101

Introduction to Orthographic Views

Foundations of Engineering

Introduction to Orthographic Views

3D Sketching

Planometric

Isometric

Perspective

Oblique

Last time

Pictorial views distort dimensions

• Limits the quantitative information given

Pictorial views also distort angles

• Limits the quantitative information given

Need a method of communicating objects visually that is entirely unambiguous and can show a high level of detail and accuracy.

Orthographic Views

Can be sketched, drawn with technical instruments or CAD

Lines of Sight

Non parallel lines of sight radiating from a point

Observer view point

View of object projected onto picture plane

Picture plane (paper or computer screen)

Lines of Sight

Parallel lines of sight

Observer at an infinite view point

View of object projected onto picture plane

Picture plane (paper or computer screen)

Capturing information – photograph ortho!

Orthographic Projection

Orthographic views are defined by using parallel lines of sight

Projectors perpendicular to plane

Lines of sight perpendicular to plane

Objects depth is not represented in this view

Plan (Top) View

Plan (Top View)

Plane of projection (horizontal)

Perpendicular to plane


Line of Sight


Perpendicular to plane

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Boundary Box

Unfold the glass box surrounding the object

Example

Drawing a simple shape



• Decide which view is which (front, plan etc)

• Draw the envelopes which determine the overall shape

Front viewFront

Top

End


Add V-notch to front view. Assuming the V goes right through


Transfer V-notch info. to other views


Add groove to side view


Transfer groove info. to other views


Tidy up the plan view

Lets have a crack at this one


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First and Third Angle Projection

• We will only ever produce drawings using third angle, however you must also be able to read first angle

• Two standard orthographic techniques, first and third angle orthographic

1st Angle

3rd Angle

• In 1st angle, the lines of sight pass through the object

Line of Sight

This face is this face

First Angle Projection

First Angle Projection

Symbol for 1st Angle

Third Angle Projection

• In 3rd angle, the lines of sight go through the viewing plane to object

Symbol for 3rd Angle

Third Angle Projection

Some things to watch out for

Multiple solutions if incomplete information given

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Drawings’ (as in the course text)The Basics

TOP

FRONT

TOP

FRONT

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• Drawings must have a border and a title block

TOP

FRONT

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• Maximise use of the available space on page

• Remember to leave enough space around each orthographic view to add dimensions

• Notes can be added to give more information

TOP

FRONT

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• Views must be labeled; TOP, FRONT, RIGHT, LEFT

• Orientate object so that major surfaces are parallel with view planes

Orthographic Drawing Conventions

The Basics - Layout

The Basics - Text


• Always use CAPITALS

6mm 3-4mm

• Gothic font is the traditional style for hand lettering

• Very light guidelines may be used

• The following page of examples of letters and numerals is taken out of New Zealand drawing standards

• Painter

• Writer

• Theroest

• Teacher

• Film maker

• Sculptor

composing motion.....

Whitney Museum, New York, US

Dec 9 2011 - 31 May 2012

Fountain (1959)

A Color Box, 1935

Len Lye (1901-1980)

Universe

Scaling Up Universe 1994

Centre Pompidou, April 2000

Tate Modern, July 2007

Australian Centre Moving Image, Melb, 2009

Ikon Gallery, Birmingham, 2011

Blade(1965)

Blade

Blade Pukekura Park (2001)

design

model

manufacture

commission

A 48 metre Wind Wand being installed on the New

Plymouth waterfront to celebrate the Millennium

48m Wind Wand

Undergrad Design 2000

Water Whirler

Wellington 2006

Thank you!

Today's Summary

Orthographic Drawing

• How to show 3D objects in 2D

• Imagine 1st angle uses a transparent object and 3rd angle uses a transparent viewing plane

• We will only produce drawings in 3rd angle

Conventions of Orthographic Drawing in Engineering

• Drawing layout

• Boarders, Title Block

• Text

lecture 18 sketching 2015

Documents

angle3rd angle

orthographic viewscan

basics views

basics drawings

multiview drawings

viewing plane

dimensions notes

plan viewlets