Ch.1 Introduction to Graphics Communication

1
Ch.1 Introduction to Graphics Communication

• Importance of technical graphics
• Traditional engineering design Changes in the
  engineering design process
• What you will learn the manual drafting portion
  of CE En 112
• Technical drawing tools that you need
• ANSI standard sheet sizes
• Basics Line weight pencil grades
• Alphabet of lines
• Scales

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Importance of technical graphics

• Technical drawings A language used in the
  design process for communicating, solving
  problems, quickly and accurately visualizing
  objects, and conducting analysis
• A graphical representation of objects and
  structures and is done using freehand,
  mechanical, or computer methods

3
From traditional linear design process to
newconcurrent design process

• Traditional A linear, segmented activity
  involving problem identification, preliminary
  ideas, design refinements, analysis,
  optimization, and documentation
• Concurrent A team activity involving
  coordination of the technical and non-technical
  functions of design and manufacturing within a
  business

The CAD database becomes a communication medium.
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What you will learn in the manual drafting
portion of CE112
Visualization Learn to mentally control visual information
Graphics theory Learn to construct engineering geometry and master basic project techniques
Standards Learn a set of rules that govern how parts are made and technical drawings are represented
Conventions Master commonly accepted practices and methods used for technical drawings
Tools Learn how to use drafting tools, both hand-held and computer tools
Applications Learn how technical graphics are used in engineering design
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Whats the difference between artistic drawing
and technical drawing?
Artistic drawing vs. Technical drawing
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Projection techniques we learn
Parallel projection Orthographic Axonometric (Isometric)
Parallel projection Orthographic Multiview ( auxiliary)
Parallel projection Oblique Cabinet
Parallel projection Oblique Cavalier
Perspective projection Linear One-point
Perspective projection Linear Two-point
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Projection types
Multiview vs. Isometric
Cavalier vs. Cabinet oblique
Perspective vs. Oblique
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Samples of drawing conventions and standards
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Manual drafting tools for technical drawing
Two mechanical pencils 0.7 and 0.5 mm, or 0.5 and 0.3 mm combinations Pencil grades HB and H, or F and 2H combinations)
One compass and one divider
One set of 45- and 30/60-degree triangles
Two scales (one English unit and one Metric unit)
One irregular curve (French curve)
One protractor
One good eraser (and if you can afford, one erasing shield)
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Use of drafting tools a few examples
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ANSI Standard Sheet Sizes typical title block
layouts
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Pencil grades and Line weight
Remember that Accuracy, Neatness, and Speed count
in technical drawing
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Alphabet of lines (1)
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Alphabet of lines (2)
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Civil engineering scale English unit and Metric
unit
See Fig 1.50 through 1.60.
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Reading a civil engineers scale
See fig 1.50 through 1.60 for other types of
scales.