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 Sketching technique e.g.
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 component (proportional)
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. Engineering graphics E.g. Anatomy of a technical drawing
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

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. 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. The title should include sufficient information to identify the type of drawing e.g general arrangement, or detail. It should also clearly describe in a precise way what the drawing portrays The basic requirements for a title block located at the bottom right hand corner of a drawing are
The registration or ID number
The drawing title
The Legal Owner of the Drawing
These items should be written in a rectangle which is at the most 170mm wide. The tile block should also include boxes for the legal signatures of the originator and other persons involved production of the drawing to the required quality. The drawing should also include a symbol identifying the projection. The main scale and the linear dimension units if other than "mm".
The drawing title block should indicate the date of the first revision.   In separate boxes to the title block the current revision with an outline description of the revision should be indicated.    On completion of each drawing revision an additional revision box should be completed thus provide a detailed history of the drawing.

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

24. 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.

25. Lettering Characteristic of good lettering Should be neat, not sloppy
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

26. Lines Pencil Description Example B/2B/0.5mm Continuous thick
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:
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
2H/H/
0.3mm
B/2B/
0.5mm
2H/H/
0.3mm
2H/H/
0.3mm

27. Standard line types used in technical drawing
Lines
Standard line types used in technical drawing

28. 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

29. Abbreviations

30. 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