1. Introduction to AutoCAD Engineering Drawings
April 17
Introduction to AutoCAD Engineering Drawings
Dr. Kevin Wong
Industrial Centre

2. Learning Outcomes
Upon completion of the workshop, students should be able to:
Explain the principle and conventional representation of engineering drawings according to engineering standards,
Apply the features and functions of typical CAD systems for producing CAD drawings,
Communicate through CAD drawings.

3. Manual Drawing Vs CAD

4. Introduction to CAD Computer Aided Drafting/Design
Basic skills for nowadays’ Engineer
Communication media among different discipline of people in different place
Can be simply classify into 2 types of CAD system – 2D and 3D
Some advantages of using CAD
Accuracy
An accuracy of up to 14 decimal places
Speed
Revising and editing drawings can be done quickly with minimum effort
Reuse of drawing content can be done easily
3D Representation and Analysis
Interference checking and 3D animations can be easily performed

5. Introduction to CAD AutoCAD
AutoCAD2015 Free Trial
AutoCAD
One of the most well-known 2D CAD software developed by Autodesk
Widely be used to output construction drawings for civil engineering, architecture, and building services
Other applications include electrical PCB design, garment design and facility management
Get a Trial Version (30-days)

6. Engineering Drawing Created by AutoCAD

7. Architecture Drawing Created by AutoCAD

8. Starting AutoCAD Auto CAD 2015
Start up > Autodesk > AutoCAD Mechanical 2015 > AutoCAD 2015
Auto CAD 2015

9. User Interface (AutoCAD classic)
Menu Bar
Current File Name
Layers
Toolbar
(Icon)
Draw Toolbar
User Coordinate System (UCS)
Graphic
cursor
Drawing Area
(Graphic Window)
Status Bar
X, y, z coordinate system

10. AutoCAD User Interface
Tabs
Click here to expand panel
Tooltip

11. AutoCAD User Interface
Dynamic Input
The key allows you to toggle between the different input field
The key allows you to display a list of valid command options
Cursor
Dynamic Prompt
Length Dimension
Current Input Field
Angle Dimension

12. Mouse Interface Middle button Scroll to zoom in or zoom out
Right button
Click to activate the right click menu
Left button
Click the specific points and select pull down menu or graphic icon
(Selection)

13. Keyboard Interface Enter Delete
Go to next step of command / repeat last command
Delete
To erase lines or any sketches
Spacebar
Go to next step of command / repeat last command

14. To Set Up a Drawing Step 1: New a draw Show the Menu bar
File > New > OK 1
Menu Bar 3 2

15. To Set Up a Drawing Step 2: Define the drawing units
Format > Unit > Millimeters > OK 1 3 2 4

16. To Set Up a Drawing Step 3: Load the line types1
Step 3: Load the line types
Format > Line Type > Load
Common used linetype:
- Continuous , Hidden, Center, Dashed 2 3 4

17. To Set Up a Drawing Step 4: Create layer for drawing control
Format > Layer > New Layer
New – Create a new layer
Delete – Delete a layer
Current – Set the selected layer to be the active layer
Color – Set layer’s color
Linetype – Select/Load linetype for a layer
Lineweight – Select the thickness of the line for a layer. 1 2 3

18. AutoCAD User Interface
Draft Setting
- Turn on and off the options by clicking on the buttons in the status bar
Status Bar
Remark:
Off Status
On Status
Show/Hide Lineweight
Grid Display
Ortho Mode
Quick Properties
Snap Mode
Infer Constraints
Polar Tracking
Dynamic Input
Object Snap
Allow/Disallow Dynamic UCS
Object Snap Tracking

19. To Set Up a Drawing Step 5: Define the drawing limits
Format > Drawing Limits 1
Specific upper right corner: E.g.: 420, 297
Specific lower left corner: E.g.: 0,0 2
Dwing Sheet
Drawing Sheet
297
420

20. Draw Command - Line & Rectangle
By specify
Co-ordinates (start & end point)
Dynamic input (start point, distance & angle)
Command of line = l
Rectangle
- By specify
Co-ordinates (first corner point & other corner point)
Command of rectangle = rec
@10,3
@10,3 10
30
0,0
0,0
0,0

21. Features of AutoCAD Draw with Absolute Cartesian Coordinate
0, *4, *2, *0,0
Absolute
X-coordinate
Y-coordinate
Draw with Absolute Polar Coordinate
0, * 4< *4< *0<120
Absolute
Distance
Angle +Y
*4<120
2,3
120o
-X, +Y
+X, +Y
180o
*0<120 -X +X
0,0
0,0
4,0
*4<180
X=0, Y=0
-X, -Y
0,0
+X, -Y

22. Features of AutoCAD Draw with Relative Cartesian Coordinate
-2, @5, @0, @-5,-2
Relative
X-coordinate
Y-coordinate
Draw with Relative Polar Coordinate
0, @ 5< @3<90 @5.83<211
Relative
Distance
Angle +Y
211o
@0,2
@3<90
-X, +Y
+X, +Y
@-5,2
-2,1
@5,0
90o
@5.83<211 -X +X
@5<0
X=0, Y=0
-X, -Y
+X, -Y

23. Activity 1
Write a list of relative coordinates used to draw the following figure
Cartesian
0,0 ..
Polar
0,0 .. 50

24. Activity 1 - Solution
Write a list of relative coordinates used to draw the following figure
Cartesian
0,0
@50,0
@0,10
@-10,0
@-30,40
@0,-60
Polar
0,0
@50<0
@10<90
@-10,0
@50<127
@60<270 50

25. Zoom View > Zoom > All View > Zoom > Window
April 17
Zoom
View > Zoom > All
View > Zoom > Window
View > Zoom > In
View > Zoom > Out
Zoom > Window
Zoom > In
Zoom > All
Zoom > Out

26. Draw Command – Circle & Ellipse
April 17
Draw Command – Circle & Ellipse
Circle & Ellipse
Circle
By specify
Center point & radius
Command of circle = c
Ellipse
- By specify
Center point, first end point of axis with angle & distance of other axis
Command of ellipse = el 10 10
@15<0o
0,0
0,0

27. Draw Command – Arc Center, Star, End Arc Center, Star, End Arc
April 17
Draw Command – Arc
Center, Star, End Arc
Center, Star, End Arc
By specify
Co-ordinates (center point, start point of the arc & end point of the arc)
Dynamic input (center point, radius with angle & end point of the arc)
Command of arc = a
50
135
0,0
0,0
@10<0o
@10<0o

28. Modify Command – Copy & Move
Step 1. Select object to copy
Step 2. Select base point
Step 3. Specify the point to move
Command of copy = co/cp
Move
Step 1. Select object to move
Step 2. Select base point
Step 3. Specify the point to move
Command of lengthen = mo

29. Modify Command – Trim & Extend
Step 1. Select object to act as the boundary
Step 2. Select object to trim
Command of trim = tr
Extend
Step 1. Select object to act as the boundary
Step 2. Select object to extend (please noted that the location of the selected point define which side to extend)
Command of extend = ex

30. Modify Command – Fillet & Chamfer
Step 1. Type in “r” for radius
Step 2. Input the radius (e.g. 10)
Step 3. Select the first edge & second edges to form the radius
Command of fillet = f
R10

31. Modify Command –Chamfer
Chamfer Two Distances
Step 1. Type in “d” for distance
Step 2. Input the first & second chamfer distance
Step 3. Select the first & second lines to form the chamfer
Command of chamfer = cha
Chamfer Length & Angle
Step 1. Type in “d” for distance
Step 2. Input the first chamfer distance
Step 3. Input the chamfer angle from the first line.
Step 4. Select the first & second lines to form the chamfer
Command of chamfer = cha
First d
First d
Angle
Second d

32. Practical Exercise 1 Use the (50,50) be starting point Staring Point
April 17
Practical Exercise 1
Use the (50,50) be starting point
Staring Point

33. April 17
Practical Exercise 2
Starting point B is (370,90) and use discretion for sizes not given
Staring Point