Technical Drawing Visual Communication of Technical Information

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Technical DrawingVisual Communication of
Technical Information
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Technical DrawingVisual Communication of
Technical Information

• Unit Overview several classes
• Precise Drawings Give More Information
• Types of Technical Drawing
• Isometric Projections
• Parallel, Perspective, and Oblique
• Orthographic Projections
• Multi-view Sketches
• Practice

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Tech Drawing -- Overview

• Good drawings convey detailed information about
  solutions to technical problems. In this unit you
  may learn
• Technical Drawing (focus of two types)
• Puzzle cube design and fabrication
• Orthographic and Isometric Layouts
• Manufacturing diagrams

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How can we present an object and learn the most
about it?
This view shows a square object with a number and
some other detail
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Isometric Projection
This view shows two sides and more information.
Note All vertical lines are parallel
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Isometric Projection
This view shows three sides and even more
information. All vertical lines are parallel
all other lines are 30 to 60 degrees above the
horizon.
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Isometric Projection
A see-through version lets us infer information
about the hidden sides
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Oblique Projection
The front is drawn on the X and Y axes. The side
and top are drawn at an oblique (not square)
angle in the Z direction. A lot of information
is shown regarding the front less about the top
and side.
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Parallel Projection
Parallel lines remain parallel regardless of how
they really appear. Are these beams parallel?
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Perspective Projection
Parallel lines meet in the distance as they
really appear
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Perspective and Parallel
The cube is scaled to be 12 ft.
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How can we make a standard drawing of this object?
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To begin

• All vertical lines are perpendicular
• to the horizon

Horizon
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Next

• All other lines rise at 30 degrees
• from the horizon

Horizon
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Continue

• All lines that complete the diagram are parallel
  to one of the three main lines

Horizon
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Complete

• The final isometric drawing presents three sides
  and infers information about the other sides

Horizon
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Practice
Height

• Take a few minutes to copy EACH of these
  isometric figures in your notebook or on plain
  paper

Start with each of the three isometric axes
Width
Depth
1.
Add vertical lines from the corners. They should
be parallel to the center line
2.
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Practice

• Take a few minutes to copy EACH of these
  isometric figures on a practice sheet

Add lines for width parallel to the width axis
3.
Finish the cube with lines for depth parallel to
the depth axis
4.
Erase where you need to
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Practice

• Draw an isometric sketch of the boxes in the
  diagram

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This is Isometric Paper
To make drawing easier Use isometric paper Graph
paper with lines That follow isometric 60-degree
axes Use this to practice Drawing
isometric figures
Horizon
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More Practice

• There are seven 3-D figures made of cubes on
  your work sheet.
• Construct each using plastic cubes.

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More Practice

• Then draw each on isometric paper.

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Isometric Projection
A standard method of 3-dimentional (3D) drawing
that shows the most detail about three adjacent
sides of an object.