CE En 112 Engineering Drawing with CAD Application Chapter 1: Introduction to Graphics Communication

Lecture Outline Introduction (1.1 – 1.5, 1.7) What will you learn? (1.9) Drawing tools (1.8) Media (1.8.2) Alphabet of lines (1.6) Scales (1.8.3 – 1.8.5) Next class Section numbers shown here apply to Chapter 1 of Textbook (B) from Bertoline-Wiebe-Miller “Fundamentals of Graphics Communication, 3/e)

After completing this chapter, you will be able to: Describe why the use of graphics is an effective means of communicating when designing Define standards and conventions as applied to technical drawings Describe the design process Identify the important traditional tools used to create technical drawings Use sketching to draw lines, circles, arcs, and curves Read and use scales Identify the types and thickness of the various lines in the alphabet of lines Create a design sketch using pencil Identify and use sketching tools Follow good hand-lettering practice

Introduction (1.1-1.5, 1-7) Engineers: Creative people who use technical means to solve problems. They design products, systems, devices, and structures to improve our living conditions. (p.4) Technical Drawings: a clear, precise language (non-verbal) used in the design process for communicating, solving problems, quickly and accurately visualizing objects, and conducting analyses A graphical representation of objects and structures is done using freehand, mechanical, or computer methods

Introduction (con’t) 92% of the design process is graphical The remaining 8% is mathematics and written communication Breakdown of Engineer’s time Who uses engineering graphics? All aspects include graphics communication Fig. 1.1

Introduction (con’t) Practice Exercise 1.1 Attempt to describe the part shown in this figure verbally to the person seated next to you Fig. 1.89 How easy is it to describe a part such as this without the use of graphics?

Introduction (con’t) An evolving 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. Fig. 1.12 Fig. 1.14 Fig. 1.15

What Will You Learn? (1.9) CE En 112 Manual Drafting Visualization Learn to mentally control visual information Graphics theory Learn to construct engineering geometry and master basic projection 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 Will You Learn? (con’t) Artistic drawing vs. Technical drawing What’s the difference?

What Will You Learn? (con’t) Parallel projection Orthographic Axonometric (Isometric) Multiview (& auxiliary) Oblique Cabinet Cavalier Perspective projection Linear One-point Two-point

What Will You Learn? (con’t) Multiview vs. Isometric Cavalier vs. Cabinet oblique Perspective vs. Oblique

What Will You Learn? (con’t) Drawing Conventions (1.5): commonly accepted practices, rules, or methods (e.g., dashed line for hidden feature) Standards (1.5): set of rules that govern how technical drawings are represented (e.g., ANSI standards)

Drawing Tools (1.8) 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)

Drawing Tools (con’t) The use of drafting tools

Media (1.8.2) Media: surfaces upon which an engineer or technologist communicates graphical information. Different types include: Tracing paper (a thin, translucent paper used for detail drawings) Vellum (tracing paper chemically treated to improve translucency) Polyester film (transparent, waterproof, and difficult to tear, “Mylar”) The American National Standard Institute (ANSI) has established standard sheet sizes and title blocks for media used in technical drawings

Media (con’t)

Alphabet of Lines (1.6) Pencil Grades Line Weight Remember that Accuracy, Neatness, and Speed count in technical drawing

Alphabet of lines (con’t)

Alphabet of lines (con’t)

Alphabet of lines (con’t) AutoCAD® Linetypes ACAD ISO series lines are very large. For this class, use standard line types starting from BORDER to PHANTOM lines. We will see these line types in AutoCAD.

Scales (1.8.3 – 1.8.5) Civil Engineering Scale

Refer to the Chapter 1 Supplement for other types of scales. Scales (con’t) Reading a civil engineer’s scale Refer to the Chapter 1 Supplement for other types of scales.

Next Manual Drafting Lecture (Jan 29) Purchase drafting tools needed for manual drafting portion of class if you have not done so Read Chapter 2 in the graphics communication book