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ME-102 Engineering ME-102 Engineering GraphicsGraphicsLecture # 1

By: Muhammad Jawad QarniResearch Associate

Faculty of Mechanical EngineeringGhulam Ishaq Khan Institute of Engineering Sciences & Technology

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Course OutlineCourse Outline Role of graphics in engineering Drawing instruments and equipment 2D and 3D space relationship Multiview and orthogonal

representations Pictorial drawings and free hand

sketching Sectional views Auxiliary views development Dimensioning and tolerancing Fasteners and connectors Production drawings computer-aided drawings and drafting

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Text Book and Other Text Book and Other ResourcesResources

Text Book: Technical Graphics Communication 3rd edition by Eric N. Wiebe and Garry R. Bertoline

Lectures, Soft Copy of the Book and for other information, Please visit FME homepage

http://192.168.151.50

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Grading Policy (Subject to change)Quizzes = 5%Assignment = 5%Lab = 30%Mid = 20%Final = 35%Attendance = 5%

Note:

Full marks (5%) for 95% or above attendance

0 marks for 80% or less attendance

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DrawingA drawing is a graphical representation of

objects and structures and is done using freehand, mechanical or computer methods.

A drawing serves as a graphic model or representation of real object or idea.

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Engineering DrawingAn engineering drawing is a drawing or a set of drawings that communicates an idea, design, schematic or model.

Different types of drawing

For e.g. mechanical engineers need productions drawing to manufacture a component or assembly.

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Engineering graphics It refers basically to the use of drawings to

represent design ideas, configurations and specifications and to use analysis required for an engineering project.

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Design ProcessEngineering design sequence….

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Graphics in Design ProcessTechnical graphics is a real and complete language

used

in the design process for:

1. Visualization2. Communication3. Documentation

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Visualization Visualization is the ability

to mentally picture things that are not there.

Ability to visualize problem solutions and communicate them through sketches is one of the most important skill of a designer.

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Communication Refinement of your initial

sketches so that your design solution can be communicated to others without ambiguity.

Usually done by creating a three dimensional (3D) model

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Documentation Is a process to

permanently record that solution.

2D drawing follow strict standard practices.

These standards are the language used to communicate graphically.

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StandardsStandards are sets of rules that govern how technical drawing are presented.

Some common standards are:ANSI: American national standard instituteASME: American society of mechanical

engineers. ISO: International standard organization. JIS: Japanese standardsMIL: U.S. Military

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Instruments In order to create a manual engineering

drawings various instrument are used.

They are….

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Drawing boards

Size:

1000(mm) x 1500(mm)

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CompassThe compass is used to draw circles and arcs of varyingdiameters

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T-Square

StockBlade

Working Edge

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A set square or triangle is an object used in technical drawing, with the aim of providing a straightedge at a particular to a baseline.

The most simple form of set square is a triangular piece of transparent plastic with the centre removed.

Set squares

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French Curves

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Scales (Ruler)

mm

inch

The international organization that established the metric standard is ISO. The system is called the International System of Units.

Mostly use millimeter scale

Conversion (Inch to mm)

1” (1 inch) = 25.4 mm

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Pencils

The following will be used in labs..

1 H 2 H HB

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Drawing sheet sizeDrawing Sheet Size Size in mm Size in inches

A0 1189 x 841 46.81 x 33.11

A1 841 x 591 33.11 x 23.39

A2 594 x 420 23.39 x 16.55

A3 420 x 297 16.55 x 11.69

A4 297 x 210 11.69 x 8.27

A5 210 x 148 8.27 x 5.84

A6 148 x 105 5.84 x 4.13

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Types of Lines

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Types of Lines…

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Common Line Symbols Visible outline (Approx 0.5)

Hidden outline (Approx 0.3)

Center Lines

Phantom lines

2mm 1mm

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Common Line symbols… Cross Section Lines or Cutting plane line

Dimension Lines

Dimensions (mm or inch)

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Sketching process

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Sketching Techniques

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Engineering Drawing RulesAlways use a sharp edge pencil.Make all lettering the same size.Use engineering paper (A3, A2 etc)

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Freehand Technical Lettering

Single stroke lettersGeneral Proportions of letters

◦ No fix standards for proportions of standards◦ It should be such that it looks pleasant to eyes

LETTERS (Normal)LETTERS (compressed)

LETTERS (Extended)

Proportions

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Pencil TechniquesThe best pencil for

lettering on most surfaces are the 1H, 2H, and HB grades.

Hold your pencil in the position shown. It should make approximately a 60o angle with the paper.

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LetteringThe style of engineering lettering we will use

in the lab is Single Stroke Gothic Lettering◦ An example of the characters is shown on

next slide◦ Notice that only capital letters are

demonstrated, since we will use only capital letters on drawings

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Single Stroke Gothic Lettering

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Title Box

Name: A B C

Reg #: 2009XXX

Title : …………………

Date : 19 JAN 2009

8

8

8

8

100mm

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Try to follow the water in this illustration….

Confused????

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Thank you….