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 VisualizationLearn to mentally control visual information Graphics theory Learn to construct engineering geometry and master basic project techniques StandardsLearn a set of rules that govern how parts are made and technical drawings are represented ConventionsMaster commonly accepted practices and methods used for technical drawings ToolsLearn how to use drafting tools, both hand-held and computer tools ApplicationsLearn 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 learn Parallel projectionOrthographicAxonometric (Isometric) Multiview (& auxiliary) ObliqueCabinet Cavalier Perspective projectionLinearOne-point Two-point

Projection types Multiview vs. IsometricCavalier 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.