autocad lab manual

1

AutoCAD Lab Manual

EBXD2103/EDXD2103

Engineering Drawing

Faculty of Science and Technology

Open University Malaysia

Version 1

January 2014

2

Table of Contents

Pages

Learning Objectives 3

Introduction 3

1. Using the Basic Command in AutoCAD 3

1.1 To Begin an AutoCAD Drawing 3

1.2 Starting a New Drawing 4

1.3 Command Entry and Using Short-cuts 6

1.4 Using Sub-command Object Snaps (OSNAP) 6

2. Begin Your Drawings 9

2.1 Task 1: Create square ABCD 9

2.2 Task 2: Create a template 9

2.3 Task 3: Create an Orthographic Drawing 19

2.4 Task 4: Create an Isometric Drawing 23

2.5 Task 5: Create 3-D Solid Drawing 29

3. Summary 35

4. FAQs 35

3

AutoCAD Lab Manual

Learning Objective: At the end of this lesson, you should be able to:

apply all basics commands in AutoCAD

produce 2D drawing

produce orthographic drawing

produce isometric drawing

produce 3D drawing.

INTRODUCTION In this lab manual you are going to produce AutoCAD drawings with your computer. The AutoCAD you will learn are basic 2D drawing, orthographic drawing, isometric drawing and basic 3D drawing. You can used this lab manual as a guide for your AutoCAD laboratory practices. 1. Using the basic commands in AutoCAD It is important for you to understand all basic commands in AutoCAD because it will help to produce an accurate and neat drawing. The basic commands that you must know are draw commands, modify commands and object snap. These commands will be used frequently in any AutoCAD drawings.

1.1 To Begin An AutoCAD Drawing

To begin an AutoCAD drawing, you first begin with Startup Dialog Box. Figure 1.1 shows a Startup Dialog Box. With this dialog box, you choose the setting for your drawing. That is, Imperial or Metric system. You also can open a drawing, strart a drawing from scratch, use

a template or wizard. Click OK when you have decided your choice.

Not all the AutoCAD software will automatically generate this dialog box in your program.

You have to activate it yourself.

AKTIVITI 1.1

4

Figure 1.1: Startup dialog box

1.2 Starting a New Drawing

Before you start to draw, you need to decide what system of drawing units that you will use

in the drawing, and then choose a drawing template file appropriate for those drawing units.

Choose Drawing Units

A drawing unit can equal one inch, one millimetre, or any other system of measurement.

Choose a Drawing Template File

When you start a new drawing, AutoCAD accesses a drawing template file to determine

many default settings such as unit precision, dimension styles, layer names, a title block, and

other settings. Many of the settings are based on whether the drawing template file is

intended for use with a drawing created in inches, feet, millimetres, centimetres, or other unit

of measurement.

5

Customize a Drawing Template File

By customizing your own drawing template file, you save yourself a lot of work changing settings, and you also ensure that the settings are standardized.

Choose a drawing template file

Start a new drawing, choose a drawing template file similar to what you need for your discipline and units of measurement. You can also create your own drawing template.

Specify units and precision

Specify a unit format and precision. Millimetre or inches.

Define various styles

Specify values and settings for text, dimensions, and other styles.

Specify additional settings

Determine other settings, including layers, grid spacing, line types, and layouts.

Save the drawing template

file

Save the file in the Template folder using a DWT file extension.

You can create several drawing template files for different projects, and you can choose one when you click New.

1.3 Commands Entry and Using Short-Cuts You have already learnt the system and basic concepts of AutoCAD. AutoCAD program offer many short-cuts for his users. These short-cut can help you to create your drawings in a simple and quicker mean. Table 1 are short-cuts commonly used for command entry.

6

Table 1

Command Short Cuts

Arc a Line l

Circle c Ellipse el polyline pl Hatch bhatch Mtext t, mt Area aa

New file new Open file open

Array ar Chamfer cha

Copy co, cp Distance di

Erase e Extend ex Fillet f

Mirror mi Move m

Polyline edit pedit Polygon polygon

Rectangle rec Redo redo Rotate ro Save save

Stretch s Trim tr Undo undo Zoom z

1.4 Using Sub Command Object Snaps (OSNAP) To create an accurate AutoCAD drawing, you must know how to use sub command Object

Snaps (Obsnap) effectively. Object snaps become active when the object snap target box

passes over an object location such as an intersection or endpoint. Depending on the

complexity of your drawing, you can increase or decrease the area that is influenced by object

snaps. Here are some sub-command of Object Snaps that you will used frequently in AutoCAD drawing as follow: (i) Endpoint Snap to Endpoint - Snaps to the closest endpoint of an object. Figure 1.2 shows a line in which a circle will be drawn at end point A. In Figure 1.3 the target box with a symbol square has snap at the end point A. You just need to click at your mouse; a circle will be drawn at endpoint A as shown in Figure 1.4.

7

Figure 1.2

Figure 1.3

Figure 1.4

(ii) Midpoint

Snap to Midpoint mean snaps to the midpoint of an object. Figure 1.5 shows a line in which a circle will be drawn at midpoint A. In Figure 1.6 the target box with a symbol triangle has snap at the midpoint A. You just need to click at your mouse; a circle will be drawn at endpoint A as shown in Figure 1.7.

Figure 1.5

Figure 1.6

Figure 1.7 Figure 1.8 shows how to used object snap snap to tangent which is used for draw line tangent to two circles.

8

Figure 1.8

Your steps will be as follow: Command: line (select snap to tangent for circle A and select again snap to tangent for circle B) Figure 1.9 shows how to used object snap snap to centre which is used for drawing line between the centers of two circles.

Figure 1.9 Your steps will be as follow: Command: line (select snap to center for circle A and select again snap to center for circle B).

9

2 Begin Your Drawings

2.1 Task 1 Draw a square ABCD as shown in Figure 1.10.

Figure 1.10 Follow this steps: Command: line Specify first point: pick any point (i.e. point A) Specify next point: 100 (move the crosschair to right side and press enter (point B) Specify next point: 100 (move the crosschair to your upward and press enter (point C) Specify next point: 100 (move the crosschair to your left side and press enter (point D) Specify next point: c (press enter twice). 2.2 Task 2 Draw a template as shown in Figure 1.11.

Figure 1.11

10

Step1 Format your drawing layer as follow:

Layer name Line t type Line weight

0 Continuous 0.4 hidden hidden default center center default

dimension Continuous default Construction line Continuous default

Figure 1.12 After you have formatted all layers, check the layer property tool bar as shown in Figure 1.12. You can activate any layer that you have formatted with this tool bar. Step 2 Locate centre A, B and C. Draw circles A, B dan C as shown Figure 1.13.

Figure 1.13 To locate the center point A, B and C, you need to use modify command offset. From pulldown menu Modify offset Specify offset distance: (type distance you want to offset) press enter click the object you need to offset and move the crosschair to the direction you want the object to be offset and left click the mouse once.

11

Step Procedures

1 Active layer center. 2 Draw two center lines P and Q for center of circle B at any

convenient length. 3 Use command offset to offset center line P with distance 80 mm

to right side to obtain center line R and then offset center Q downward with distance 15 mm to obtain center line S (to obtain center for circle C).

4 Use command Offset to offset center line S with distance 65 mm upward to obtain center line U and then offset center R with distance 20 mm to left to obtain center line T ( to obtain center for circle A).

5 Active layer 0 to draw all three circles. Step 3 Draw line DE as shown in Figure 1.14. Command: line Specify first point: snap to tangent (pick at circle R20) Specify next point: snap to tangent (pick at circle R24)

Figure 1.14 Step 4 To draw arc R60 and arc R120 R60 From pull down menu, select Draw, select Circle and select option Tan, Tan, radius (click it with your mouse) as shown in Figure 1.15. Specify point on object for first tangent of circle: click at R30 Specify point on object for second tangent of circle: click at R20 (see Figure 1.16) Insert the value of radius : R60

12

R120 Use the similar steps as for R60. Specify point on object for the first tangent of circle: click at R30 Specify point on object for second tangent of circle: click at R24 Insert the value of radius : R120

Figure 1.15

Figure 1.16

13

Step 5 After you have drawn arc R60 and R120, you need to trim the extra part of circle. Command: trim Select object: pick circle R30, R24 and R20 then press enter. Click at Circle R60 and the click again at Circle R120. The extra parts will be trimed. Finally your drawing will appeared as Figure 1.11. Step 6 You need to insert dimensions into your drawing. First step is to format your dimensional style. You can follow this means: From pull down menu, select Format Dimension style (see Figure 1.17)

Figure 1.17

A Dimension Style Manager dialog box will be appeared at your computer screen as shown in Figure 1.18. Click at Modify, a Modify Dimension Style: ISO-25 will appeared in your computer screen (see Figure 1.18).

14

Figure 1.18 The modifications you need to do are as follow:

1. Open dialog box for Lines as shown in Figure 1.19. Make changes for Extend beyond dim

lines to 1.25 and Offset from origin to 1.5.

Figure 1.19

15

2. Open dialog box for Symbols and Arrows as shown in Figure 1.20. Make changes for Arrow size to 3.

Figure 1.20 3. Open dialog box for Text as shown in Figure 1.21. Make changes for Text styles, Text

height to 4 and Offset from dim line to 1.5.

Figure 1.21

16

4. Open dialog box for Fit as shown in Figure 1.22. Select Both text and arrows.

Figure 1.22 5. Open dialog box for Primary Units as shown in Figure 1.23. Adjust Precision to 0.

Figure 1.23

17

After you had done all the changes for dimension style, you can start to insert your dimension into your drawing. To activate the AutoCAD drawing tools, you can follow this steps: From pull down menu dimension. Figure 1.24 shows all type of dimensions available in AutoCAD.

Figure 1.24 Step 6 After you have completed insert all the dimensions into your drawing, you can start to save you drawing. Choose any convenient file name. For example, you file is drawing1. Step 7 The final step to complete your drawing is plotting / printing. You need to activate Plot - model dialog box from pull down menu as shown in Figure 1.25. You have to make some adjustment for your printing.

18

Figure 1.25 Follow this steps to plot/print your first drawing (refer to Figure 9.26).

Step Procedures

1 Printer/plotter Select a printer connected to your computer.

2 Paper size Select a paper size compatible to your printer 3 Plot area: What to plot:select window

Select the area you want to print begin to pick from top left corner (A) to bottom right corner (B). You can refer Figure 9.23

4 Fit to paper: Untick 5 Scale: select 1:1 6 Tick Center the plot (this is to ensure your drawing are

positioned to the center of the paper). 7 Select Drawing orientation 8 Click ok to plot or print

19

Figure 1.26

2.3 Task 3

Create an Orthographic drawing.

Figure 1.27

20

Step 1

Divide your drawing area as shown in Figure 1.28 using layer construction line.

Figure 1.28

Step 2

Draw the plan as shown in Figure 1.29 using layer 0.

Figure 1.29

Step 3

Activate the construction line layer to project your front view from plan as shown in Figure

1.30.

21

Figure 1.30

Activate layer 0 to draw all the object lines (continuous) and layer hidden to draw all the

hidden lines (hidden) as shown in Figure 1.31.

Figure 1.31

Step 4

Activate layer construction line to project the side view as shown in Figure 1.32.

22

Figure 1.32

Activate layer 0 to draw all the object lines (continuous) and layer hidden to draw all the

hidden lines (hidden) as shown in Figure 1.33. You also need to activate layer center to insert

all the center lines into your drawing. After you have completed to draw all views, you turn

off layer contruction line, since you do not need to print any construction lines in this

drawing as shown in Figure 1.34.

Figure 1.33

23

Figure 1.34

Step 5 Now insert the dimensions into your drawing, save your file and printed your drawing.

2.4 Task 4

Create an Isometric Drawing

Isometric drawing is a type of pictorial drawing in engineering drawing. You can create

isometric drawing with your AutoCAD application software. You must first activate your

drawing mode to isometric mode.

By setting the Isometric Snap/Grid, you can easily align objects along one of three isometric

planes; however, although the isometric drawing appears to be 3D, it is actually a 2D

representation. Therefore, you cannot expect to extract 3D distances and areas, display

objects from different viewpoints, or remove hidden lines automatically.

If the snap angle is 0, the axes of the isometric planes are 30 degrees, 90 degrees, and 150

degrees. Once you set the snap style to Isometric, you can work on any of three planes, each

with an associated pair of axes as shown in Figure 1.35 and Figure 1.36:

Top - Aligns snap and grid along 30- and 150-degree axes.

Right - Aligns snap and grid along 30- and 90-degree axes.

Left - Aligns snap and grid along 90- and 150-degree axes.

Figure 1.35

24

Left

Top

Right

Figure 1.36

Before you begin your isometric drawing, you must activate the isometric mode in your

computer. Follow this steps:

Command: snap (press enter)

Specify snap spacing: ON/OFF/Aspect/Style/Legacy/Style/Type: Style (press enter)

Enter Snap Grid Style:[Standard/Isometric]: isometric (press enter)

Spacing vertical snap spacing : press enter.

Figure 1.37

25

Figure 1.38 shows an orthographic drawing and isometric of a block.

Figure 1.38

Step1

Use isoplane left to draw line L and a, then use isoplane right to draw line W and p (see

Figure 1.39)

Figure 1.39

Active isoplane left

Command: line (press enter)

Specify first point: pick any point (press enter)

Specify next point: 80 (move the cross chair downward) (press enter)

Specify next point : 15 (move the cross chair upward) (press enter twice)

26

Change to isoplane right


Specify first point: ( pick at endpoint of line 80 mm line)

Specify next point: 60 (move the cross chair to right side) (press enter)


Step 2

To draw line b and c (see Figure 1.40).

Figure 1.40

Use isoplane left


Specify first point: ( pick at endpoint of line a)

Specify next point: 60 (move the cross chair to left side) (press enter)


Step 3

To draw line e, f and g (Figure 1.41)

Figure 1.41

27

Use isoplane right

Command: line

Specify first point: ( pick at endpoint of line a)

Specify next point: 45 (move the cross chair to right side) (press enter) - to draw line e

Specify next point : 10 (move the cross chair upward) (press enter twice) to draw line f

Specify next point: 15 (move the cross chair to right side) (press enter twice) - to draw line g

Step 4

To draw line h, i and j (Figure 1.42)

Figure 1.42

Use isoplane right to draw line h

Command: line

Specify first point: ( pick at lower endpoint of line c)

Specify next point: 45 (move the cross chair to right side) (press enter) - to draw line h

Press F5 to isoplane left line i

Specify next point : 65 (move the cross chair downward) (press enter twice)

To draw line j

Command: line

Specify first point: ( pick at endpoint of line h)

Specify next point: 40 (move the cross chair to upward) (press enter twice).

28

Step 5

To draw line k and l (Figure 1.43)

Use isoplane left

Command: line

Specify first point: ( pick at endpoint of line j at upper end)

Specify next point: 50 (move the cross chair to downward) (press enter).

Specify next point: click at endpoint of line f (press enter twice) to draw line l.

To draw line m, n, o and p

Figure 1.43

Use isoplane left

Command: line

Specify first point: ( pick at lower endpoint of line m)

Specify next point: 65 (move the cross chair to upward) (press enter) - to draw line n.

Press F5 to isoplane right line o

Specify next point : 35 (move the cross chair downward) (press enter)

Specify next point: use osnap endpoint joint the line endpoint of line d ( press enter twice)

to draw line p.

29

Step 6

To draw line q, r, s and t (Figure 1.44)

Figure 1.44

Use command copy

To copy line p for line q (use osnap enpoint).

Use line command to draw line s and t (use osnap endpoint).

2.5 Task 5

To create 3-D Solid Drawing

A 3D solid drawing will enable you to create orthographic drawing, isometric drawing and

auxiliary view in AutoCAD.

Now you will create a 3D solid drawing with Figure 1.45.

30

Figure 1.45

Step 1

From pull down menu Views 3D views SE Isomtric

The WCS will be as shown in Figure 1.46

Figure 1.46

Step 2

To draw part A (see Figure 1.47)

Command: box (press enter)

Specify first corner or [Center]: pick any point

Specify other corner or [Cube Length]: select length or type length press enter

Now you have press F8 to activate Ortho On

Specify length:80 (press enter)

Specify witdth: 50 (press enter)

Specify height:10 (press enter)

31

Figure 1.47

Step 3

To draw part B (see Figure 1.48)

Command: box (press enter)

Specify first corner or [Center]: pick point A

Specify other corner or [Cube Length]:

select length or type length and press enter



Specify witdth: 50 (press enter)

Specify height: 40 (press enter)

Figure 1.48

32

Step 4

You have command union to joint both part A and B.

From pull down menu Modify Solid Editing Union

Select both parts.

Step 5

To create fillet with radius 20 (see Figure 1.49 and 1.50)

From pull down menu Modify Fillet Union

Select First object or [Undo Polyline Radius Trim Multiple]: Select edge B

Enter Fillet radius : 20 (press enter) (press enter again)

Figure 1.49

Figure 1.50

33

Step 6

To create chamfer with distance 15 at both edge (see Figure 1.51).

From pull down menu Modify Chamfer

Select First line or [..................]: Select edge C

Enter Surface Selection Option : (press enter

Specify base surface chamfer distance: 15 (press enter)

Specify other surface chamfer distance: 15 (press enter)

Select an edge or [Loop]: select edge C (press enter)

The completed chamder is shown in Figure 1.52

Figure 1.51

Figure 1.52

Step 7

To draw wedge C (refer Figure 1.53)

From pull down menu Draw Modeling Wedge

Specify first corner or [Center]: pick point D

34

Specify other corner or [Cube Length]: select length or type length and press enter



Specify witdth: -8(press enter)

Specify height: 20 (press enter)

Figure 1.53

Step 8

You have command union to joint both part A & B with part C (see Figure 1.53).

From pull down menu Modify Solid Editing Union

Select all parts.

Step 9

To draw cylinder D

From pull down menu Draw Modeling Cylinder

Specify center point of base : pick center point of R20 at upper surface(use osnap snap to

center)

Specify base radius : 10 (press enter)

Specify height : 10 (press enter)

Now you have completed your 3D view as shown in Figure 1.54.

35

Figure 1.54

3. SUMMARY

In this lab manual, your have learnt various type of AutoCAD drawings. AutoCAD is a

powerful application Computer Aided Drawing. You can use it to create, modified and save

drawing.

4 FAQs

Question 1 What type of system can I choose for my AutoCAD drawing?

Answer You can choose one of the following system when you start your

drawing

i. Metric ii. Imperial (inch)

Question 2 If my drawing consists of different types of line, what should I do?

Answer You can format the layer in your drawing and use one layer for one

type of line.

Question 3 Can I choose my own dimension style for my drawing?

Answer You can format your own dimension style. Follow these steps:

Pull down menu format dimension style modified (dimension dialog box)

Question 4 If I want the object lines of my drawing to have different thickness

with center lines and hidden lines, what should I do?

Answer Adjust the line weight of the object line layer in layer dialog box.

Question 5 Can I use one file to draw two or more drawings?

Answer Yes, you can use one file to draw two drawing or more. But it is not

advisable if your computer screen is small you might need to zoom or

scroll your drawing many times.

36

Question 6 Can I convert a 3D drawing into 2D drawing?

Answer You can convert a 3D drawing into 2D drawing with SOLVIEW and

SOLDRAW command.

Question 7 If my printer only can use A4 size paper for printing but my

AutoCAD drawing has bigger scale than A4 size, can I print this

drawing?

Answer You can print your drawing, scale down the printing size by adjusting

the plotting scale in plotting dialog box

Question 8 Can I change the dimension text?

Answer You can change the dimension text by using edit text command.

Question 9 Can I adjust the zoom for my drawing?

Answer You can zoom drawing by using the Zoom command from Home tab

(Ribbon Bar) in the Utilities panel, click zoom.

Question

10

How can I ensure that my First Point of Sketch starts at the end of

the End Point of the previous sketch?

Answer You can use OSNAP tools. The OSNAP tools can be accessed from the

OSNAP button at the status bar. You can also press SHIFT & right-

click.

Question

11

If my drawing uses Polyline or Block References, can I convert the

drawing into individual elements?

Answer You can use EXPLODE command to convert object such as polyline,

dimension, hatch or block references to convert it into individual

elements.

Question

12

Can I modify the text style in my drawing?

Answer Yes, to create or modify a text style is by opening Menu Browser and

clicks Format and select Text Style.

Question

13

How can I display the Center Mark of a Circle?

Answer You can display the Center Mark by setting it in the Dimension Style

Manager Dialog Box. You can control the size of the center mark by

typing a figure in the Size edit box.

Question

14

Can I set the Dimension Tolerance in my 2-D drawing.

Answer Yes, use the Tolerances tab in the Dimension Style Manager Dialog

Box, select Tolerance and select the types of Tolerance type that you

want it to display in your 2-D drawing.

Question

15

Can I rename a LAYER?

37

Answer Yes, to rename a layer, use Layer Properties Manager command, right-

click the layer name and choose Rename Layer or press F2.

Question

16

Can I set the Plot Area that I wish to plot?

Answer Yes, by using Plot Area options, you can select your plotting style to

Display, Extents, Limits or Window.

autocad lab manual

Documents