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

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

From traditional “linear” design process to new“concurrent” 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.

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

What’s the difference between artistic drawing and technical drawing?

Artistic drawing vs. Technical drawing

Projection techniques we learnParallel projection Orthographic Axonometric

(Isometric)

Multiview (& auxiliary)

Oblique Cabinet

Cavalier

Perspective projection

Linear One-point

Two-point

Projection types

Multiview vs. Isometric

Cavalier vs. Cabinet oblique

Perspective vs. Oblique

Samples of drawing conventions and standards

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)

Use of drafting tools – a few examples

ANSI Standard Sheet Sizes & typical title block layouts

Pencil grades and Line weight

Remember that Accuracy, Neatness, and Speed count in technical drawing

Alphabet of lines (1)

Alphabet of lines (2)

Civil engineering scale: English unit and Metric unit

See Fig 1.50 through 1.60.

Reading a civil engineer’s scale

See fig 1.50 through 1.60 for other types of scales.