EM101_Sept2013_AutocadLab

FACULTY OF ENGINEERING, ARTCHITECTURE & BUILT

ENVIRONMENT

COMPUTER-AIDED-DRAFTING MANUAL

EM101/ED109/EE202

ENGINEERING GRAPHICS & DESIGN / ENGINEERING DESIGN

Lecturer/Instructor: _________________________________________

Name: __________________________________________________

Student ID: ______________________________________________

Course: _________________________________________________

SEPTEMBER 2013

EM101/ED109/EE202 | Engineering Graphics and Design

Updated Jan 2012 1 | P a g e

TABLE OF CONTENTS

1 General Instructions 2

2 Laboratory Protocols 2

3 Lab Experiments

LESSON 1 Startup 3

LESSON 2 Drawing Commands 5

LESSON 3 Modify Commands 1 8



LESSON 6 Dimensioning 17

LESSON 7 Orthographic Projections 19

LESSON 8 Solid Modeling 22

LESSON 9 Sectional Views 29



1 GENERAL INSTRUCTIONS

The lesson in this manual are designed to provide the students some fundamental concepts in

computer-aided drafting. Students are required to practice the exercises as designed in the

manual. All exercises are to be complete within the allotted time.

2 LABORATORY PROTOCOLS

Students are required to comply with the following rules when in the lab.

1. Swapping of lab session is strictly not allowed. Work done in other than the registered lab

session will be graded zero (0).

2. Always be punctual. Students later than 15 minutes are not allowed to enter the lab.

3. All hand phones must be switched off. (Lecturer/instructor reserves the right not to allow

students who do not follow this rule to enter the lab).

4. Eating and drinking in the lab are strictly prohibited.

5. Always follow the instruction of the lab instructor or lecturer before the start of the lab.

6. Clean the working area and return all benches to their respective places before you leave

the lab.

7. All class work must be completed and submit within the allotted time. Any late submission

will be graded zero.



LESSON 1 STARTUP

Objective

This topic introduces the fundamentals in starting up of AutoCAD.

Learning Outcome

The student is able to begin drawing with AutoCAD and create new layer (lines).

Introduction

Design and drafting activities can be accomplished by using a computer, and hence it is refer

as Computer-Aided Design (CAD). AutoCAD and Solid Work are common CAD software

package used to create designs and generate drawings for documentations. It has better

accuracy, productivity and the ability to share CAD file with other software programs.

Starting AutoCAD

To start drawing by AutoCAD, the student must be able to identify the:

1. Graphics Area

The large central area of the screen is the graphics area. It displays the lines, circles and

other objects you draw that will make up the drawing.

2. Command Line

Any command that is entered or any prompt that AUTOCAD issues appear here. It

gives the current state of drawing activity.

3. Toolbars

AutoCAD provides a variety of toolbars. It contains a number of icons that can be

picked to invoke commands for drawing or editing objects (Lines, arcs, circle, and etc.)

4. Pull-down Menu

It is at the top of the screen just under the title bar. Selecting any of the words in the

menu bar activates, or pulls down, the respective menu

5. Screen (side) Menu

Screen menu can be made appear by selecting Options from tools pull-down menu.

Display background color can be changed from here

6. Status Bar



Status bar is a set of informative words or symbols that give the status of the drawing

aids. It appears at the very bottom of the screen. The drawing aids can be toggled on or

off by single clicking (pressing the left mouse button once)

Command Entry

There are few possible methods for entering commands in AUTOCAD:-

1. Toolbars

2. Pull-down menu

3. Keyboard

Function Keys

F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12

Help Flip

screen

Osnap

Toggle Tablet Isoplane Coords Grid Ortho Snap Polar

Osnap

Tracking DYN

Working with Files

Same as Microsoft Window

Units

You can choose either metric (mm) or Imperial unit (British unit) to start your drawing.

Unit can be changed by selecting Units from the Format pull-down menu.

Drafting Setting Object Snap

Object snap can be activated by selecting Drafting Setting from Tool pull-down menu.

You can activate or deactivate object snap mode from there.

Create New Layer

Click layer properties manager

Click new layer or Alt-N

Click color ,choose the required color) , press OK

Click line type, press LOAD, choose required lines type, click OK



LESSON 2 DRAWING COMMANDS

Objective

This topic enables the student to learn the basic drawing commands (line, rectangle, polygon,

erase, circle, ellipse, arc)

Learning Outcome

The student is able to draw by using line, rectangle, polygon, erase, circle, ellipse, arc

commands

Coordinate Entry

There are many ways to specify the coordinates (tell AutoCAD the location of points) when

you draw or edit objects. There are two coordinates formats: Cartesian format and polar format.

The Cartesian format specifies x and y (e.g. 3, 7), while the polar format indicates the distance

and angle (e.g. 6 45). The coordinates types are absolute coordinates (3, 7 or 6 45) and

relative coordinates (@ 3, 7 or @ 6 45). Absolute coordinates are typically used to specify

the first point of a line or other object while relative coordinates are typically used for the

next point.

Drawing Commands line, rectangle, polygon, erase, circle, ellipse, arc

Line

Select the line icon or type line

Type 10, 10, click enter

Type @ 70 0, click enter



Type c (close), click enter

Erase

Select the erase icon or type erase

Click the unwanted object and click enter

7

5

1



Circle

Below are methods in drawing circle:

1. Center radius

Select the circle icon or type circle

Select center point

Type 50 (radius = 50)

2. Center diameter


Select center point

Type D (D = diameter)

Type 100 (diameter = 100)

3. 2 points

Draw 2 lines as shown


Select 2p

Select first point (as shown in figure)

Select second point (as shown in figure)

Ellipse

Draw the figure as shown

Select the ellipse icon or type ellipse

Type c (center point)

Select first point

Select second point

Arc

Draw the figure as shown

Select the arc icon or type arc

Type c (center point)

Select starting point of the arc

Select end point of the arc

5

3

1st 2nd

E

n

8

3

F

ir

First

8

3

Sec

ond



Exercise



LESSON 3 MODIFY COMMANDS 1

Objective

This topic enables the student to learn the basic modifying command (move, copy, offset, array,

rotate, mirror)

Learning Outcome

The student is able to draw and modify using move, copy, offset, array, rotate, mirror

commands

Drawing Commands move, copy, offset, array, rotate, mirror

Move

Draw a rectangle (60 30)

Click the move icon or type move

Select the rectangle (4 boundaries) and click enter

Click the lower left edge (point to hold)

Move the rectangle to new location

Copy


Click the copy icon or type copy

Select the rectangle (4 boundaries) and click enter

Click the lower left edge (point to hold)

Drag the rectangle to new location

Offset

Draw a line (length = 50)

Click the offset icon or type offset

Type 10 (distance to offset)

Select the line

Click side to offset

51

Sou

Off



Array

There are two types of array:

1. Rectangular array

Select the array icon or type array

Select/Click the rectangle drawn (object) and click enter

Type 2 (number of row) and 4 (number of column)

Type 100 (row offset distance) and 150 (column offset distance)

Click enter

2. Polar array

Draw a circle (diameter 15)

Select the array icon or type array

Select/Click the circle (object)

Select polar method

Select center point

Select Total number of item & angle to fill

Type 8 (total number of item)

Type 360 (angle to fill column)

Click enter

Rotate

Draw a rectangle

Select the rotate icon or type rotate

Select the rectangle drawn (object) and click enter

Select base point (lower left edge)

Type 25 (rotation angle)

1

Ro

Colum

1

Cente

3



Mirror

Draw the Figure shown

Click the mirror icon or type mirror

Select the rectangle and press enter

Select first mirror point and then the second mirror point

Type N to keep the source object and Y if want to erase source object

Exercise

First

mirr

Seco

nd

8

1

4Mirr




Objective

This topic enables the student to learn more modifying command (construction line, trim,

extend, fillet, chamfer)

Learning Outcome

The student is able to draw and modify using construction line, trim, extend, fillet, chamfer

commands

Drawing Commands construction line, trim, extend, fillet, chamfer

Construction Line

Select the construction line icon

Type a

Type 20 (angle = 20)

Select any location to locate the line

Trim

Draw horizontal and vertical line

Select the trim icon or type trim

Select the horizontal line (trim boundary)

Click enter

Select the unwanted line

B A



Extend

Draw 2 lines

Select the extend icon or type extend

Click vertical line (extend boundary)

Click enter

Click horizontal line

Fillet

Draw 2 lines as illustrated

Select the fillet icon or type fillet

Type r (r = radius)

Type 10 (10 = radius of fillet)

Select first object (horizontal line)

Select second object (vertical line)

Chamfer


Explode the object

Select the chamfer icon or type chamfer

Type d (distance)

Type 20 (first chamfer distance)

Type 15 (second chamfer distance)

Select first line of the chamfer

Select second line of the chamfer

5

7

Sec

ond

First 2

1



Exercise




Objective

This topic enables the student to learn more modifying command (rectangle, polygon, explode,

hatch, scale, multiline text)

Learning Outcome

The student is able to draw and modify using rectangle, polygon, explode, hatch, scale,

multiline text commands

Drawing Commands rectangle, polygon, explode, hatch, scale, multiline text

Rectangle

Select the rectangle icon or type rectangle

Select first point

Type @ 40, 90 (X distance = 40, Y distance = 90)

Polygon

Select the polygon icon or type polygon

Enter 6 (number of sides)

Specify center of polygon

Type I for inscribed or C for circumscribed

Click enter

Type 40 (radius)

Explode

Draw a rectangle

Select the explode icon or type explode

Select the rectangle drawn (object) and click enter

4

91st

Inscri Circu

E



Hatch


Select the hatch icon or type hatch

Click Add: pick points

Select the A area and click enter

Scale


Select the scale icon or type scale

Select the object

Select base point (lower left edge)

Type 2 (scale factor)

Multiline Text

Click the multiline text icon or type multiline text

Specify first corner and second corner

Change the text height

Type UCSI, MALAYSIA

Exercise

UCSI,

2nd

1st

A B

4



LESSON 6 DIMENSIONING

Objective

This topic enables the student to learn and apply the dimension commands

Learning Outcome

The student is able to draw and show all the dimensions

Dimension

There are several types of dimensions, including linear, align, radius, diameter, angular etc.

Exercise



LESSON 7 ORTHOGRAPHIC PROJECTION

Objective

This topic enables the student to learn the multiview projection

Learning Outcome

The student is able to differentiate the first and third view projection

Orthographic

Orthographic projection is a mean of representing a three dimensional (3D) object in two

dimensions (2D). It is divided into:

1. First angle projection

2. Third angle projection

First angle projection



Third angle projection

Exercise



LESSON 8 SOLID MODELING

Objective

This topic enables the student to learn the basic of 3D solid modeling

Learning Outcome

The student is able to produce a 3D solid modeling drawing

3D Models

Three basic types of 3D models is created to represent the actual object:

1. Wireframe model

Like a model constructed of 12 coat hanger wires. Each wire represents an edge of the

actual object. The surfaces of the object are not defined; only the boundaries of surfaces

are represented by edges. The model is see-through since it has no surfaces to obscure

the back edges. It contains no volume.

2. Surface models

As all surfaces and edges of the object are defined, it has a better description than the

wireframe models. It has volume but no mass.

3. Solid models

A complete computerized replica of the actual object, which contains the

A complete computerized replica of the actual object which is the most complete and

descriptive type of 3D modeling. It contains complete surface and edge definition, as

well as description of the interior features of the object. If a solid model is cut into half,

the interior features become visible. It is considered to have mass, as it is solid.

3D Coordinate

When creating a model in three-dimensional drawing space, the concept of the X and Y

coordinate system which is used for two dimensional drawing must be expanded to include the

third dimension, Z, which is measured from the origin in a direction perpendicular to the plane

defined by X and Y



World Coordinate System (WCS) and User Coordinate System (UCS)

Primitives

Solid primitives are the basic building blocks that make up complex solid models. The

ACIS primitive commands are:

1. Box

Select NW Isometric

Select the box icon or type box

Type @30, 40, 40 to specify the corner of the box (distance X = 30, Y = 40, Z = 40)

Click enter

2. Cone

Determine the desired UCS (the base of the cone lies on XY plane)

Select the cone icon or type cone

Specify center point, radius and height of the cone (height is in Z-axis)

3. Cylinder

Determine the desired UCS (the base of the cylinder lies on XY plane)

Select the cylinder icon or type cylinder

Specify center point, radius and height of the cylinder (height is in Z-Azis)

4. Wedge

Determine desired UCS (the base of the wedge always parallel with XY plane while

slope is always along X-axis)



Select the wedge icon or type wedge

Specify first corner, other corners (@40, 60, 0), and height

5. Sphere

Select the sphere icon or type sphere

Specify center point and radius

6. Torus

Select the torus icon or type torus

Specify center point

Specify radius of torus and radius of tube

7. Extrude

Draw a rectangle (the object should lies on X-Y plane)

Select the extrude icon or type extrude

Select the rectangle (objet)

Specify the height of rectangle

Moving Solids

1. Rotate 3D

Type rotate3d

Select object (rectangle)

Type 2p

Specify 1st and 2nd points of axis

Type angle of rotation 25

2. Mirror 3D

Type mirror3d

Select object and click enter

Type 3 points

Click the 3 points location

Type N

1st

2nd



Boolean Operation Commands

1. Union (join 2 or more objects)

Type union

Select object and click enter

2. Subtract (subtract 1 set of solid from another)

Type subtract

Select the object that you want to keep and click enter

Select the object to remove and click enter



3. Intersect (creates a solid of intersection (common volume) from selected solids)

Type intersect

Select all desired solids and click enter

4. Chamfer

Type chamfer

Select solid at desired edge and click enter

Specify base surface chamfer and the other surface chamfer, click enter

Select edges to be chamfered and click enter



5. Fillet

Type fillet

Select object (desired edge to fillet)

Specify radius value and click enter



LESSON 9 SECTIONAL VIEW

Objective

This topic enables the student to learn the concept of sectional view

Learning Outcome

The student is able to produce the sectional view drawing

Section View

A section view is a view of the interior of an object after it has been imaginary cut open to

reveal the objects inner details. Hatch lines (section lines) are drawn in the section view to

indicate the solid material that has been cut through. For mechanical drawings, a cutting plane

line is drawn in an adjacent view to the section view to indicate the plane that imaginary cuts

through the object. Arrows on each end of the cutting plane line indicate the line of sight for

section view. A thick dashed or phantom line should be used for cutting plane line

Exercise

EM101_Sept2013_AutocadLab

Documents

lab experiments lesson

g e lesson

drawing commands

lab instructor

graphics area

toolbars autocad

registered lab session

computeraided design