MEMB113 ENGINEERING GRAPHICS & CAE

1. MEMB113 ENGINEERING GRAPHICS & CAE 02 Engineering Graphics & Sketching

2. Contents • Overview • Sketching • Engineering graphics & manual drawing • Drawing tools • Drawing sheets and layout • Lettering • Lines • Scale • Abbreviations

3. Overview • Engineering graphics communication involves the use of visual material to convey technical ideas and problem solutions. • Engineering or technical drawing – one of the most widely used method. • Definition of drawing: • A graphic representation of an idea, concept or an entity which actually or potentially exists in life.

4. Overview • Importance: • A way of communication between engineers at all stages of the design & problem solving from initial ideas, design, analysis & manufacturing. • For Visualisation, Communication and Documentation Visualisation The ability to mentally picture things that do not exist in front of the eyes. Communication The design solution should be communicated to others without ambiguity Documentation Permanent record of the solution for future reference.

5. Overview • Types of drawing : • artistic • technical • Illustrations • rendering

6. Overview • Examples of different drawing types 3-D computer model of the interior of an office building A dimensioned technical/mechanical drawing

7. Sketching

8. Sketching • 3 methods of creating technical drawings • Freehand, mechanical & digital • Technical sketching is the process of producing a rough preliminary drawing representing the main features of a product or structure • Normally done by freehand, generally less finished, less structured/ restricted, & take less time to produce

9. Sketching • Technical sketches • Used extensively in the first stage of design process to visualise or convey ideas • An informal tool used by everyone involved in the design & manufacture of a product

10. Sketching • Sketching tool • Paper, pencils, eraser • Sketching technique e.g. • Straight line sketch • Circle & arc • Component (proportional sketch) • Pictorial sketch • In sketching, proportionality is important. • Even though it is a freehand sketch, the lines should be relatively sharp and straight for a good quality sketch. Mechanical Sketched

11. Sketching • Sketching straight line

12. Sketching • Sketching circle Sketching component (proportional) Sketching circle

13. Sketching • Multi-view and pictorial sketches

14. Engineering Graphics & Manual Drawing

15. Engineering graphics • Drawings are widely used in engineering applications: manufacturing, design, structural, electrical, etc. • Standards and conventions • To ensure everybody using the same method • Commonly used: • ANSI, ASME, ISO, JIS, MS, DIN, BS • What will you learn • Producing engineering drawings • Interpreting engineering drawings • Graphics theory, visualisation, • standards, conventions, • applications,etc.

16. MEMB113 | MANUAL DRAWING | CHAPTER 1 Engineering graphics • E.g. Anatomy of a technical drawing

17. Drawing layout • One of the important aspect in technical drawing is the layout • What is drawing layout? • Example of engineering drawing with layout • Paper size • ‘Components’ of a layout • Title block • Our layout

18. Drawing layout • Drawing layout is the standard template and components of a drawing • E.g.

19. Drawing layout • Drawing sheets – paper sizes • Usually based on 'A' series • Drawing sheets material - paper, linen, plastic film • Drawing sheet layout • Sheet frames or border • Usually 20mm for A0 & A1, 10mm for others • Title block or title frame • Represents general information source for a drawing • Usually at bottom right-hand corner A0 : 1189x841 A1 : 841 x 594 A2 : 594 x 420 A3 : 420 X 297 A4 : 297 X 210 A5 : 210 X 148 A6 : 148 X 105 All in mm

20. Drawing layout - components Revision Table A revision table is normally located in the upper right of the drawing frame, or at the bottom on the left side of the title block. All modifications to the drawing should be documented here. Material or Parts List If the drawing contains a number of parts, or if it is an assembly drawing, a tabulated parts list is attached to the bottom right of the drawing frame, just above the title block. The parts list should give the following information: the part number the part name the quantity required material specifications the drawing number of each individual part other applicable information When the parts list is very large a separate drawing sheet may be used for the parts list alone. Zoning A drawing may be divided up into a grid using letters and numbers. When zoning is used it is located inside the drawing frame. Zoning allows easy references to various parts of the drawing by referencing a coordinate such as C7. Title Block The title block is normally placed in the bottom right of the drawing frame, and it should contain the following information: - the name of the company or organization - the title of the drawing - the drawing number, which is generally a unique filing identifier - the scale - the angle of projection used, either first or third, generally shown symbolically - the signature or initials of the draftsman, checker, approving officer, and issuing officer, with the respective dates -other information as required http://www.metrication.com/drafting/layout.htm

21. Drawing layout – title block • A title block is the form on which the actual drawing is a section. The title block includes the border and the various sections for providing quality, administrative and technical information.   The importance of the title block cannot be minimised as it includes all the information which enables the drawing to be intepreted, identified and archived. • E.g.

22. UNLESS STATED OTHERWISE ALL DIMENSIONS IN mm TOLERANCES LINEAR: ANGULAR DRAWN BY MY FULL NAME IS VERY LONG ME 000000 SEC 01A DATE: 04/07/2005 UNIVERSITI TENAGA NASIONAL DRAWING TITLE MATERIAL CAST STEEL CHECKED BY FINISH AS MACHINE SCALE 1:1 DWG NO. 001 SHEET 1 OF 1 Our layout

23. Lettering • Text is an important part of a technical drawing. Not all info required on technical dwg can be communicate graphically such as dimensions. • One method of creating text is by freehand lettering. The standard style for freehand lettering is single-stroke Gothic lettering.

24. MEMB113 | MANUAL DRAWING | CHAPTER 2 Lettering • Characteristic of good lettering • Should be neat, not sloppy • Should be uniform and consistent i.e. same height, proportion & inclination – use guidelines • Should have proper spacing of letters and words • Should not contain unnecessary frills • Should use capital letters except for standard abbreviation e.g. mm, kg • Recommended minimum height 2.5mm • Recommended height 5mm to 7mm • Underlining of lettering should be avoided

25. Pencil Description Usage Example B/2B/0.5mm Continuous thick Drawing outlines & visible edges Continuous thin Hatching, dimension & projection lines Continuous wavy thick Limit of partial view Dashed thin Hidden detail Long & short dash thin Center lines Lines • Different line types for different purposes - to ensure drawing to be read quickly & accurately • Types of lines and thickness of line • Commonly used line types & thickness: 2H/H/ 0.3mm B/2B/ 0.5mm 2H/H/ 0.3mm 2H/H/ 0.3mm

26. Lines Standard line types used in technical drawing

27. Scale • What does it mean? • Scale indicates the relative size of the drawing object with the real object • Scale used should always be stated on drawing – a very important info that is usually written in the title block. • 'do not scale' / 'not to scale‘ / NTS – the drawing is not drawn to a certain scale • Recommended scale • 1:1 for full size • for greater than full size • 2:1 for twice full size • 10:1 for ten times full size • for reduced size • 1:2 for half full size • 1:10 for tenth full size • other common scale • 1:5, 1:20, 1:50, 1:100, 1:500 etc. Actual size 1:1 2:1 1:2

28. Abbreviations

29. End of chapter [02] References: Engineering Drawing, A.W. Boundy, McGraw-Hill, 2000 Fundamentals of Graphics Communication 3rd Edition, Gary Bertoline & Eric Weibe, McGraw-Hill