Autocade 2D complete course

2dmuetcourse-110709082805-phpapp02.doc Page 1 of 66

Muhammad Atif Khan K.K.
Assistant Professor
Department Of Mechanical Engineering M.U.E.T. Jamshoro

Defining CAD / CADD
 CAD
Submitted by , MOHAMMAD YOUNUS unushyd@gmail.com Page 1 of 66

An acronym for Computer Aided Design
It is synonymously used for Computer Aided Drafting.
 CADD, An acronym for Computer Aided Design & Drafting
CAD/CADD refers to the use of software and computer for creating precise engineering
drawings and designs
What is AutoCAD
 It is a general-purpose computer-aided drafting application program.
 It is the largest selling software for Computer Assisted/Aided /Automated Drafting.
 More people use AutoCAD than any other CAD software.
 Today, AutoCAD is translated into 18 languages and used by millions of users worldwide.
 AutoCAD LT is a "scaled down" version of AutoCAD and It costs less. Compared to the
full edition of AutoCAD, AutoCAD LT lacks several features. Most notably, it has no 3D
modeling capabilities.
 Autodesk has also developed a few discipline-specific enhancements of AutoCAD, such as,
AutoCAD Architecture AutoCAD Mechanical, AutoCAD Electrical, AutoCAD Civil 3D,
and AutoCAD Map 3D are examples of industry-specific CAD applications built on the
AutoCAD platform.
AutoCAD-Version history
Re Ver Re Date of
Official Vers Date of
lea Official name sion lea release
name ion release
se se
Version 1.0 1.0 1 1982, December Release 13 N/A 13 1994, November
Version 1.2 1.2 2 1983, April Release 14 N/A 14 1997, February
Version 1.3 1.0 3 1983, August AutoCAD 2000 15.0 15 1999, March
Version 1.4 1.4 4 1983, October AutoCAD 2000i 15.1 16 2000, July
Version 2.0 2.0 5 1984, October AutoCAD 2002 15.6 17 2001, June
Version 2.1 2.1 6 1985, May AutoCAD 2004 16.0 18 2003, March
Version 2.5 2.5 7 1986, June AutoCAD 2005 16.1 19 2004, March
Version 2.6 2.6 8 1987, April AutoCAD 2006 16.2 20 2005, March
Release 9 N/A 9 1987, September AutoCAD 2007 17.0 21 2006, March
Release 10 N/A 10 1988, October AutoCAD 2008 17.1 22 2007, March
Release 11 N/A 11 1990, October AutoCAD 2009 17.2 23 2008, March
Release 12 N/A 12 1992, June
Scope of AutoCAD
It is used to increase speed & accuracy in the production of drawings in any field, such as

 Civil Engg  Electrical Engg.  Structural Engg
 Construction  Electronics Engg.  Architectural Engg
industry  Biomedical  Manufacturing Engg
 Geographic  Chemical Engg  Multimedia
Information  Petroleum Engg  Land Management
Systems  Mining Engg  City & Regional
 Surveying  Industrial Engg Planning
 Facilities  Metallurgy Engg  & many more………
Management  Mechatronics
 Mechanical Engg  Computer Engg

Advantages of AutoCAD over manual/instrumental drafting
 Speed  Neatness

 Accuracy  Helps in Engineering Analysis.
 Legibility improved.  Helps in Computer Aided
 Improved Presentations. Manufacturing (CAM).
 Flexibility in Editing.  High rate of drawing production.
 Easy Storage/Transport  Enhanced visualization.
 Easy retrieval/Access of Drawings  & many more….
 Sharing CADD Drawings.

 AutoCAD Graphical User Interface (GUI) or Main screen
Graphical user interface (GUI) allow computer users to interact with computer by selecting small
images called icons to execute instructions, eliminating the need to use text commands.

The AutoCAD screen consists of following important areas. These are,

The drawing area
The blank area (On your computers it may be in black color) in the middle of the screen
where you draw. You can think of this as a sheet of drafting paper, except that this black piece

of paper can be of any size( Infinite size) — even the size of a huge factory or even the size
of a city. At the bottom of the drawing area is a tab labeled Model. We will draw on this tab.
You use the layout tabs to lay out your drawing for plotting we will learn to draw here later.
The UCS icon
Notice the symbol with two arrows at the bottom-left corner of the drawing area in Figure
above. This symbol is called the User Coordinate System (UCS) icon. The arrows point to the
positive directions of the X and Y axes.
The crosshairs
In the drawing area, notice the two intersecting lines with a small box at their intersection.
The small box is called the pickbox because it helps you to select, or pick, objects. The lines
are called crosshairs. They show you the location of the mouse cursor in relation to other
objects in your drawing. As you move your mouse around, the pickbox and crosshairs move
with your mouse. At the bottom of your screen, at the left end of the status bar, you can see
the X,Y coordinates change as you move your mouse.
The menus and toolbars
Beneath the menu bar there are two rows of toolbars. In addition, your screen has two more
toolbars, the Draw and Modify toolbar, which is probably docked at the right side of the
screen. Use the menus and toolbars together to give AutoCAD commands to draw, edit, get
information, and so on.
On the Draw toolbar, move the mouse cursor over the first button. You should see a tool tip
that says Line. Also notice the status bar, which tells you that this button creates straight-line
segments. You use toolbar buttons to execute commands.
For example, to draw a line, you click the Line button on the Draw toolbar.
The command line
All commands can be executed by typing them on the command line. Even if you use a menu
item or toolbar button to execute a command, you may see a response on the command line.
AutoCAD often provide options that must be typed in from the keyboard. Text that you type
appears on the command line.
The status bar
At the left are the X,Y coordinates. As you move your mouse, these coordinates change. (If
they don’t change, click them and move your mouse again.)

Note: You can use the CLEANSCREENON command to hide the title bar, toolbars, and status bar,
leaving more room for the drawing area. To return to the regular display, use the
CLEANSCREENOFF command or press Ctrl+0 to toggle between the two displays.

 Different ways to start AutoCAD?
You can launch AutoCAD with the following methods:
 Choose Start-(All)-Programs-Autodesk-AutoCAD 200X-AutoCAD 200X.
 Double-click an AutoCAD drawing file.
 Double-click the AutoCAD icon on the Windows desktop.
 Click the AutoCAD icon on the taskbar’s Start menu.
 Click the AutoCAD icon on the Quick Launch toolbar on the taskbar.

 QSAVE or SAVE
Quickly saves the current drawing

 Standard toolbar:
 File menu: Save or save as

 Command line: qsave or save
If the drawing is named, AutoCAD saves the drawing without requesting a file name. If the
drawing is unnamed, AutoCAD displays the Save Drawing As dialog box (see SAVEAS) and
saves the drawing with the file name you specify.
 Closing/Exiting AutoCAD
If you saved your most recent changes to all open drawings, you can exit AutoCAD without saving
the drawings again. If you have not saved your changes, AutoCAD prompts you to save or discard
the changes.
To exit AutoCAD
 Click ( X ) close button at upper right corner
 From the File menu, choose Exit.
OR
 Command line: Type QUIT or EXIT & press ENTER
 Different ways to access/start commands
You can use any of the following methods to start a command. The easiest way to start a command is to
type it in the Command Line window, other methods are

 Menu bar
 Toolbars, Right clicks on any toolbar, displays all toolbars.
 Shortcut menu, right click mouse having cursor at different positions on screen and see
different menus, called as shortcut menus.
 Using Shortcut Menus
You can right-click your pointing device to display shortcut menus from which you can quickly choose
options Shortcut menus are context-sensitive. You can display shortcut menus from most of the
following AutoCAD window/main screen areas

 Erasing objects / ERASE command
 Modify toolbar:
 Modify menu: Erase
 Shortcut menu: Select the objects to erase,
right-click in the drawing area, and click Erase.
 Command entry: erase
Select objects: Use an object selection method or
Enter L (Last) to erase the last object drawn. or
Enter all to erase all objects from the drawing.
And press ENTER when you finish selecting objects
The objects are removed from the drawing.


 Canceling a command
Sometimes you might find yourself using a command, and all of a sudden you want to stop using it
and switch to a different one. If you don’t want to complete the current command, press Esc or right-
click and choose Cancel from the shortcut menu.
 Repeating last command
AutoCAD allows you to repeat the previous command without having to select it from a user
interface element again, You can use these methods to repeat a previously used command:

 Press Enter when no command is active.
 Press the space bar when no command is active.
 Press the Up arrow key when no command is active and press Enter. You can
Step back to retrieve previously used commands within the current session and not just
the most recently used command.
 Right-click the drawing window and choose Repeat Command Name.
 Right-click the drawing window and choose Recent Input & .command name.
 Right-click the Command Line window and
choose Recent
 Command: command name
 Changing the color of an object using
properties toolbar

Select the objects whose color you want to view or modify,
and click color button in the properties toolbar as highlighted
in the figure to see available colors. Pick any desired color.
 Turning the toolbars ON and OFF
Displaying the toolbars shortcut menu
Right click on any icon/button and choose the toolbar from the list
to be displayed as shown in the figure.
Displaying the toolbars through keyboard/command
line
Command: -TOOLBAR
Enter toolbar name or [ALL]: Type any toolbar’s name such as
Draw or modify or any other toolbar’s name
Enter an option [Show/Hide/Left/Right/Top/Bottom/Float]
<Show>: Type F for float and press enter
Enter new position (screen coordinates) <0,0>: accept the default
0,0 by pressing enter
Enter number of rows for toolbar <1>: accept the default by
pressing enter.


 Undo command or Correcting mistakes
Reverses the effect of commands

 Coordinates systems used in AutoCAD
Introduction

As a general rule, everything you draw with
AutoCAD will be drawn full size/actual size.
This often comes as quite a surprise to those
who are new to CAD and have spent a number
of years working on a drawing board.

When you start drawing with AutoCAD you
do not have to decide upon a drawing scale as
you do when using a drawing board. When
drawing on paper you must decide do draw at
say, 1:20 or 1:200 depending upon the size of
the object that you are drawing so that your
scaled drawing will fit on the drawing sheet, be that A3 or A1.

In AutoCAD you do not need to decide upon a drawing scale until you come to print the drawing and
because the scaling of your drawing takes place at the printing stage, you can create drawings at a
scale of 1:1. This has particular advantages because you can, for example, measure lengths, areas and
volumes within an AutoCAD drawing and not need to compensate for any scale factor.
 LINE Command, close, undo and continue options
With the Line command you can draw a simple line from
one point to another. When you pick the first point and
move the cross-hairs to the location of the second point
you will see a rubber band line which shows you where
the line will be drawn when the second point is picked.
Each line segment drawn is a separate object and can be
moved or erased as required. To end this command, just hit the key on the keyboard.
Undo & Close options in LINE command
The undo option erases the last segment only, where as close option draws the last line segment joining
with the start point and at the same time terminates the line command.
Continue option in LINE command
At any stage you terminated/ended the line command but immediately you decide to continue the line
from last point of the last segment you just drawn, start line command when it asks for the start point
just press enter the line will be started from the end point of the last segment drawn, thus continuing
the line.

 Understanding startup dialog box-Tutorial
Starting AutoCAD
 From the start menu choose all programs, and then choose AutoCAD from the menu.
 If you have shortcut on desktop then directly double click on AutoCAD icon.

Exploring the startup dialog box
When you start AutoCAD, the startup dialog box may or may not be displayed depending upon the
default settings & the version of software, If it is not displayed then follow this,

Turn ON/OFF the display of startup dialog box
 From the Tools menu, choose Options-
Or
 Type Options at command line & press enter
 In the Options dialogue box Choose,
System-General options-Startup-select,
Show or do not show Startup Dialog box
 Choose Apply/OK.

Now close the software/AutoCAD and re-start, it you will see the startup dialogue box displayed
each time you start AutoCAD.

The dialog box provides you with four different ways to start working in AutoCAD, you can,
A. Open an existing drawing.
B. Start a drawing from scratch
C. Start a drawing based on a template.(This will be discussed later)
D. Use wizards to help you setup/start your drawing (This will be discussed later)

To open an existing drawing, click
 In the Startup dialog box, choose “Open a Drawing”, and then choose Browse. OR If AutoCAD
is already started, from the File menu, choose Open. In the Select File dialog box, select a files (If
there is no recently used file than use browse button to locate the file) & chose Open.
 Now select VIEW-ZOOM from menu bar and try zoom IN, OUT, ALL, and EXTENT options
and observe the difference between them also use PAN REALTIME, and ZOOM WINDOW &
ZOOM PREVIOUS from the standard tool bar docked in the top area of GUI/screen.


Note: Repeat this several times changing the file each time and practicing various zoom options as
listed above. Now close AutoCAD and repeat the same again and again, each time opening a
different file. When you have practiced this several times, follow the next step
To create a new drawing using Start from Scratch, click
 In the Startup dialog box, choose “Start from Scratch”. OR If AutoCAD is already started, from
the File menu, choose New, and then choose Start from Scratch in the Create New Drawing
dialog box. Select Imperial/English (For making drawing in inches & feet, or. English units) or
Metric (For making drawing in millimeters, or metric units), and then choose OK.
 A new drawing file opens, based on the English/Imperial or metric settings and with the default
name drawing1.dwg (Note: By default all AutoCAD drawing files are saved as dwg files, having
dwg as file extension).
 Now turn ON the GRIDS (Small dots displayed on screen, they are not printed they help in
visually aligning objects on screen and show the limits of working area.) if they are not visible by
pressing GRID button in the status bar at lower part of the GUI/AutoCAD main screen.
 Make any free hand using line command and mouse, forget the accuracy of the drawing.
To save your new drawing
 From the File menu, choose Save As.
 In the “Save Drawing As” dialog box under File Name, enter a name for the drawing, select
destination in “save in” and choose Save. AutoCAD automatically appends the drawing extension
(.dwg) to the new file name.
Creating a new drawing using Start from scratch option
A quick way to begin a new drawing is to start from scratch, which starts a drawing that uses settings
from a default drawing template file.
The setting you select determines default values used for many system variables controlling text,
dimensions, grid, snap, and the default line type and hatch pattern file.
English/Imperial:
Creates a new drawing based on the Imperial measurement system. The drawing is based on the
acad.dwt template, and the default drawing boundary, called the drawing limits, is 12 × 9 inches.
Metric:
Creates a new drawing based on the metric measurement system. The drawing is based on the
acadiso.dwt template, and the default drawing boundary is 420 × 297 millimeters.

 Hints & Guidelines when using AutoCAD commands
 When using command line
Commands often have options/sub-commands, which are displayed within brackets. To choose an
option, enter the option's capitalized letter (uppercase or lowercase) on the command line. If an option
is preceded by a number, such as the CIRCLE command 3Point option, enter the number and
capitalized letter.

 Commands are not case sensitive.
 Some commands display dialogue box while others display only options at command line therefore,
always keep watching command line for options while working in AutoCAD
 Space bar can also be used as ENTER / RETURN key
 If a command is in progress related help can generally be accessed by pressing F1 key.
 Hitting “ENTER” or “SPACEBAR” at “COMMAND” prompt will re-invoke the last command.
 Pressing “ESC” key is your best friend for getting out of sticky situations.

 Accelerator Keys/function keys
Use Accelerator Keys/function keys to toggle modes “On” & “OFF”. For example,

F1 = Help
F2 = Switches state of text window
F3 = OSNAP on or off.
F6 = COORDINATES on or off.
F7 = GRIDMODE on or off.
F8 = ORTHOMODE on or off.
F9 = SNAPMODE on or off.
Save often ! ! ! !
 Standard Paper Sizes

Metric ISO, Imperial ANSI and USA Architectural are
the world’s top standards for paper sizes. Of these metric
is number one!
An A0 sheet is 1m². This allows paper weights to be
expressed in grams per square meter. Example: 110gsm
paper.
The ratio - length to width - of ISO sheets is 1 to the Square Root 2. This relationship of 1:Sq root 2
is particularly important for reduction onto microfilm, or reduction and enlargement on photocopiers.
All metric equipment including microfilm cameras, microfilm printers, photocopiers, and even
drawing pen sizes, are designed around this ratio. This makes the process of archiving drawings,
resizing, and modifying drawings easy.

The ISO paper sizes are devised in such a way that each smaller size is exactly half the size of the
previous one. If you cut an A0 sheet in half you get two A1 sheets. Oversize* sheets are used when it
is desirable to give extra protection to the drawing sheets by providing a binding or trimming margin.


 In how many different ways can we enter a point or specify a location
Answer of this question is 3 or even more.

1. Entering absolute/real coordinates.
Absolute Cartesian Coordinate data entry style is X,Y ( All X , Y & Z values are given w.r.t fixed
origin.)
The simplest and most elementary form of coordinate values is absolute coordinates.

Absolute coordinates conform to the following format:
X, Y

One problem with using absolute
coordinates is that all coordinate values
refer back to the origin 0, 0 fixed in the
lower left corner.

Now, let’s make our first step into drawing
and learn about coordinate system by going
over these topics.

Try yourself-Tutorial
Command: LINE
Command: Specify first point: -2,1
Specify next point or [Undo]: 3,4
Specify next point or [Undo]: ENTER

In the example given above, we drew the
line, We gave the point information that is
asked by AutoCAD by entering real/absolute
coordinates in form of x,y. Let’s continue to
convert it into a triangle.

Command: LINE
Specify next point or [Close/Undo]:
-2,1
Specify next point or [Close/Undo]: ENTER

atifkhan68@hotmail.com 0333-2642151


 Absolute coordinate input-Tutorial- 1
First open a new drawing with imperial settings by using start from scratch, and draw it on a graph
paper and try to complete the table first and later draw it on computer,

First open a new drawing with imperial settings by using start from scratch, first on a graph paper
and later draw it on computer,




2. Entering relative coordinates:
With absolute coordinates, the origin at 0, 0 must be kept in mind at all times in order for the correct
coordinate to be entered. With complicated objects, this is sometimes difficult to accomplish and as a
result, the wrong coordinate is entered, it is possible to reset the last coordinate to become a new
origin or 0, 0 point. The new point would be relative to the previous point, and for this reason, this
point is called a relative coordinate.

The format is as follows:
@X, Y

In this format, we use the same X and Y values with one exception: the @ symbol that resets the
previous point to 0, 0 i.e. origin, and makes entering coordinates less confusing.

Let’s make the previous example by using relative coordinates. Let’s draw the same triangle by
starting from -2,1 point, going 5 units in right direction and 3 units in upper direction and end in
same -2,1 point.

Command: LINE
Specify next point or [Undo]: @ 5,0
Specify next point or [Undo]: @3,0
Specify next point or [Close/Undo]: C

As you can see, entering relative coordinates is done
by using @ symbol from the last point and entering
Δx,Δy values. @ means that we will enter relative
coordinates.

 Relative coordinate input-Tutorial- 1
First open a new file with metric settings,
If AutoCAD is already open, close all files and,
Click File menu and choose New, In the New
Drawing dialogue box select start from scratch and
choose metric & click OK, Now ZOOMOUT once
to see all GRID area.

If you just started AutoCAD than In the Startup
dialogue box select start from scratch and choose
metric & click OK
Relative Coordinate System.
‘@’ character is used for relative coordinate input.
Putting it at the beginning of an entry, the place you
are on is considered as the origin and the desired
coordinate relative to this origin is entered. Briefly,
‘@’ character means ‘with respect to.


Start LINE command,
Command: LINE
Specify first point: pick any point on the screen
at lower left corner of GRID area, and follow the
steps below.
Firstly, draw a 100-unit line.
Specify next point or [Undo]: @100,0 ‘Enter’

Then, draw a 100-unit line through Y axis.
Specify next point or [Undo]: @0,100

The 80-unit line is in negative X direction.
Specify next point or [Undo]: @-80,0

The following movement is in both negative directions
of X and Y axes.
Specify next point or [Undo]: @-20,-20

The last line is in negative Y direction.
Specify next point or [Undo]: @0,-80
Specify next point or [Undo]: Press ENTER

First open a new drawing with imperial settings by using start from scratch, and draw it on a graph
paper and try to complete the table first and later draw it on computer,




 Relative coordinate input-Tutorial - 5
First open a new drawing with imperial settings by using start from scratch, and first draw on a graph
paper and later draw it on computer,

 Relative coordinate input-Tutorial-6
First open a new drawing with imperial settings by using start from scratch, and first draw on a
graph paper and later draw it on computer,



3. Entering Relative Polar Coordinates:
Another popular method of entering coordinates is the polar coordinate mode. The format is shown
below:
@ Distance < angle or
@ Length < direction

As the preceding format implies, the polar coordinate method requires a known distance and an
angle. The @ symbol, resets the previous point to 0, 0. The direction is preceded by the < symbol,
which reads the next number as polar or angular
direction.

We know that angles increase in counter clockwise
direction in AutoCAD. The example given here
explains how to enter polar coordinates.

Command: LINE
LINE Specify first point: -2,1
Specify next point or [Undo]: @5<0
Specify next point or [Undo]: @3<90
Specify next point or [Close/Undo]: c


 Polar coordinate input-Tutorial-1
Many AutoCAD users have some troubles with angles. The reason beyond this is the lack of
information about polar coordinate system. Examining the figure below, let us start to learn polar
coordinate system.

First open a new file with metric settings,
If AutoCAD is already open, close all files and,
Click File menu and choose New, In the New Drawing dialogue box select start from scratch and
choose metric & click OK, Now ZOOMOUT once to see all GRID area.

If you just started AutoCAD than In the Startup dialogue box select start from scratch and choose
metric & click OK

Firstly, let us draw a coordinate plane and lines with entering length and angles. The formula for
polar coordinate entry is: @length<angle (between the X axis). The length and angles of our lines let
be 100 unit and 45 degrees respectively.

To draw the first line, run the line
command,
Command: LINE
Specify first point: 0,0 and press
enter
Specify next point or [Undo]:
@100<45

The angle for the second line is 45
degrees less than 180.
Repeat line command and
Command: LINE
Specify first point: 0,0 ENTER
Specify next point or [Undo]:
@100<135 and press enter

The angle for the third line is 45 degrees
less than 270.
Repeat line command,
Command: LINE
Specify next point or [Undo]: @100<225 and press enter

The angle for our last line is 45 degrees less than 360.
Repeat line command,
Command: LINE
Specify next point or [Undo]: @100<315 and press enter


 Polar coordinate input-Tutorial- 2




 Polar & Relative (Combined) coordinate input-Tutorial- 5

 Polar & Relative (Combined) coordinate input-Tutorial- 6

 Drawing Aids
Introduction
Drawing with AutoCAD is really just like drawing on a drawing board. Most new comers to
Computer Aided Design assume that they will need to learn how to draw all over again. In fact, many
of the drawing aids that AutoCAD provides are analogous to traditional drafting tools. This means
that in many respects, the drawing techniques are very similar. If you ever get stuck, think how you
would complete a task on a drawing board and then look for a similar way to do it with AutoCAD.

Grid command

Status Bar (right-click for settings)
Pull-down None
Keyboard GRID or F7


The drawing grid is a regular pattern of dots displayed on the screen which acts as a visual aid; it is
the equivalent of having a sheet of graph paper behind your drawing on a drawing board. These grid
dots are not plotted. You can control the grid spacing, so it can give you a general idea about the size
of drawn objects. The grid dots extend over the area you specify as the grid limits. The grid helps you
align objects and visualize the distances between them. If you zoom in or out of your drawing, you may
need to adjust grid spacing to be more appropriate for the new magnification.

Command Sequence/Try yourself
Command: GRID
Specify grid spacing(X) or [ON/OFF/Snap/Aspect]
<10.000>: (enter grid spacing e.g. Type 1 & press enter,
also try different values and observe changes in the
display)

Study yourself & explore other options
Although you can use the command line to control the
visibility of the grid by using the "ON" and "OFF"
options or by using the F7 key or, better still, by
clicking the GRID button on the status bar. However,
the command line does offer some additional options.
The Snap option allows you to automatically set the grid spacing to the current snap spacing

You can also change the aspect ratio of the grid. By default, the X and Y spacing of the Grid are
the same, resulting in a regular square matrix of grid points. But you can display a grid with
different X and Y spacing by using the "Aspect" option.

You can access grid settings by right-clicking the Grid button on the status bar and selecting
Settings… from the short-cut menu. You can also do this from the pull-down menu, Tools
Drafting Settings… and click on the "Snap and Grid" tab.

Limits command (Grid Limits)
You may have noticed that the grid does not extend infinitely in all directions. In fact, it is only
displayed within a finite rectangle. You can control the extent of the visible grid using Drawing
Limits.

Toolbar None
Pull-down Format Drawing Limits
Keyboard LIMITS
Drawing Limits is used to define the extent of the grid display The grid is displayed within a
rectangle defined by two pick points or co-ordinates.

Command Sequence/Try yourself
Command: LIMITS
Reset Model space limits:
Specify lower left corner or [ON/OFF] <0.0000,0.0000>:(enter co-ordinates 2,2)
Specify upper right corner <12,9>: (enter co-ordinates 8,7 )
& observe the change in grid area.


Explore other options by yourself
Drawing Limits can also be used to turn Limits mode on or off. Limits mode can be used to control
where objects can and cannot be drawn. Limits is turned off by default which means that there is
no restriction as to where points can be picked and objects drawn. When Limits is on, AutoCAD
will not allow points to be picked or co-ordinates entered at the command line which fall outside
of the specified drawing limits. If you try to pick a point outside the drawing limits when Limits
mode is turned on, AutoCAD reports to the command line:
**Outside limits
Limits mode is useful if you know the extent of your plotted drawing sheet and you want to
prevent objects being drawn outside of this area. However, Drawing Limits is most commonly
used simply to control the extent of the Grid.

Ortho command/Ortho Mode
Status Bar
Pull-down None
Keyboard ORTHO or F8

Ortho is short for orthogonal, which means either vertical or horizontal. Like the other options on the
status bar, Ortho is not really a command; it is a drawing mode which can either be turned on or off.
Ortho mode can be toggled on or off in one of three ways. The quickest way is just to click on the
ORTHO button on the status bar. The appearance of the button tells you whether Ortho is currently
turned on or turned off. When Ortho is turned on, the ORTHO button appears pressed in. You can
see how this appears by looking at the status bar illustration below. In the illustration, Ortho is turned
on but Grid and Snap are turned off.

Ortho can also be toggled on and off using the F8 Function. Finally, you can also type ORTHO at the
command prompt as in the command sequence below. With Ortho mode turned on you can only
draw lines which are either vertical or horizontal.

Try yourself,
Turn Ortho mode on now and draw some lines to get a feeling for how it works.
Command: ORTHO
Enter mode [ON/OFF] <OFF>: (type ON or OFF)
Ortho mode is probably the simplest of all the drawing aids, and historically one of the oldest. It
is either on or it is off and there are no special settings to make. You may not be surprised to
learn, therefore, that its use has largely been superseded by more recent features, particularly
Polar Tracking (You will learn later)

Snap Mode/Snap Command
Status Bar (right-click for settings)
Pull-down None
Keyboard SNAP or F9


Snap mode takes AutoCAD one step further than the drawing board. With Snap mode turned on
AutoCAD only allows you to pick points at regular intervals/jumps. The Snap is completely
independent of the display grid. However, the Grid spacing and Snap spacing are usually set to the
same value for the ease of understanding.

Command Sequence
Command: SNAP
Specify snap spacing or [ON/OFF/Aspect/Rotate/Style/Type] <10.0000>: (enter the required snap
spacing in drawing units)

Explore yourself
Although you can use the Snap command to turn Snap mode on and off, it is much more efficient
to use the F9 function key on the keyboard or to click the SNAP button on the status bar.
The "Aspect" option can be used to vary the horizontal and vertical snap spacing independently.
"Rotate" is used to set the snap grid to any angle.

You can force the display grid to conform with the snap grid by setting the display grid spacing to
zero. The display grid will then automatically change each time the snap grid is changed. When
Snap mode is turned on and the Grid is displayed, the Snap and Grid spacing are the same and the
crosshairs will jump from one grid point to another as you move across the screen.
This makes it very easy to draw objects which have a regular shape. The Snap command is used
to set the snap spacing.

All of the Snap variables can also be set using the pull down menu, Tools-Drafting Settings
dialogue box. Right-click on the SNAP button and choose Settings… from the short-cut menu.

 Direct distance input-Tutorial
Object:
Comparing the all coordinate entry methods, by creating this
simple drawing using:
 Absolute coordinate method.
 Relative coordinate method.
 Polar coordinate method.
 Direct distance entry method
Using direct distance entry ( Time saving )
A method to specify a second point by first moving the curser to
indicate the direction and then entering a distance. If ortho is
turned ON (Or Polar tracking is used.) only then we can make accurate horizontal and vertical lines
otherwise this method does not give us accuracy in drawing lines.

Procedure:
 Start the software; open a new drawing using start from scratch and English / Imperial option.
Turn ON the GRID.


 Make the object drawing four times (Each time change the color of line when using different
methods by using object properties toolbar) by following all four methods separately in the same
drawing one over the other. And try to understand difference between these methods.

Absolute Method Relative Metho Polar Method Direct Distance Entry Method
d
Type L or LINE & Press Enter L Enter L Enter L Enter
Type 2,2 & Press Enter 2,2 Enter 2,2 Enter 2,2 Enter
Type 8,2 & Press Enter @ 6 , 0 Enter @ 6 < 0 Enter Move curser right, type 6, Enter
Type 8,4 & Press Enter @ 0 , 2 Enter @ 2 < 90 Enter Move curser up, type 2, Enter
Type 6,4 & Press Enter @ -2 , 0 Enter @ 2 < 180 Enter Move curser left, type 2, Enter
Type 4,6 & Press Enter @ -2 , 0 Enter @ 2 < 180 Enter Move curser left , type 2, Enter
Type 2,8 & Press Enter @ -2 , 0 Enter @ 2 < 180 Enter Move curser left, type 2 , Enter
Type 2 , 2 Enter, Esc/Enter C Enter C Enter C Enter

 UNITS command/Drawing Units Dialog Box
Format menu: Units
Command entry: units (or 'units for transparent use)
Defines the unit and angle formats.
Length
Specifies the current unit of measurement and the precision for the
current units.
Type
Sets the current format for units of measure. The values include
Architectural, Decimal, Engineering, Fractional, and Scientific.
The Engineering and Architectural formats produce feet-and-
inches displays and assume that each drawing unit represents one inch. The other formats can
represent any real-world unit.
Precision
Sets the number of decimal places or fractional size displayed for linear measurements.


Note:-How to enter different units for length (Syntax)
Enter feet and inches using the following format/syntax:
feet'-inches" or feet’ inches" or feet inches

You can separate feet, inches, and fractional inches with a dash, a space, or nothing. You can use any
of the following syntax cases to enter valid feet-inch formatted values:
• 5’ or 60”
• 5’-9” or 5’ 9” or 5’9”
• 5’-1/2” or 5’ 1/2” or 5’1/2”
• 5’-9-1/2” or 5’ 9-1/2” or 5’9-1/2”
• 5’-9 1/2” or 5’ 9 1/2” or 5’9 1/2”
To designate inches for linear calculations, entering double quotes (“) is optional. For example,
instead of entering 5’9-1/2”, you could enter 5’9-1/2.
Warning With imperial units, CAL interprets a minus or a dash (-) as a unit separator rather than a
subtraction operation. To specify subtraction, include at least one space before or after the minus
sign. For example, to subtract 9” from 5’, enter 5’ -9” rather than 5’-9”.
Angle
Specifies the current angle format and the precision for the current angle display.
Type
Sets the current angle format.
Precision
Sets the precision for the current angle display.
Clockwise
Calculates positive angles in the clockwise direction. The default direction for positive angles is
counterclockwise.
Insertion Scale
Controls the unit of measurement for blocks and drawings that are inserted into the current drawing.
A block or a drawing that is created with units that are different from the units specified with this
option is scaled when inserted. The insertion scale is the ratio of the units used in the source block or
drawing and the units used in the target drawing. Select Unitless to insert the block without scaling it
to match the specified units.
Sample Output
Displays an example of the current settings for units and angles.
Direction
Defines the angle for 0 degrees and specifies the direction in which
angles are measured. When prompted for an angle.
Base Angle
East, North, West & South, Sets the direction of the zero angle.
Other
Specifies a direction different from the points of the compass.
Angle
Specifies a value for the zero angle when other is selected, you can
specify the angle by entering a value.
Pick an Angle Button
Defines the zero angle in the graphics area based on the angle of an imaginary line that connects
any two points you specify with the pointing device. Available only when other is selected.



 CIRCLE Command
Along with Line and Polyline, the Circle command is probably one of the most frequently used.
Fortunately it is also one of the simplest. However, in common with the other commands in this section
there are a number of options that can help you construct just the circle you need. Most of these options
are self explanatory. The Circle command, for example, offers 6 ways to create a circle,
Command: CIRCLE
Specify center point for circle or [3P/2P/Ttr (tan tan radius)]: (pick P1
anywhere or type 6,6)
Specify radius of circle or [Diameter] (pick P2 anywhere or type 2.5 as radius)

Explore and practice various circle command options

For example, the circle command gives you three extra options to define a circle. 3P which uses any
three points on the circumference, 2P which uses two points on the circumference to form a diameter
and Ttr which stands for Tangent Tangent Radius. Obviously to use this last option you need to have
drawn two lines which you can use as tangents to the circle. Try these options out to see how they
work. Note that to invoke a command option; you need only type the upper-case part of the option
name. For example, if you want to use the Ttr option, you need only enter "T". There are two more
circle options on the pull-down menu that enable you to draw a circle by defining the center and
diameter or by using 3 tangents.

 Exercise


 RECTANGLE Command

The

Rectangle command is used to draw a rectangle whose sides are
vertical and horizontal. The position and size of the rectangle are defined by picking two diagonal
corners. The rectangle isn't really an AutoCAD object at all. It is, in fact, just a closed polyline which is
automatically drawn for you.

Try yourself-Tutorial,
First, Open an imperial file by using start from scratch option,
Command: RECTANG
Specify first corner point or [Chamfer/Elevation/Fillet/Thickness/Width]: (pick
P1 or Type 0 , 0)
Specify other corner point or [Dimensions]: (pick P2 or type 12 , 9)
Notice that, instead of picking a second point to draw the rectangle, you have the option of
entering dimensions. Say you wanted to draw a rectangle 8 drawing units long and 5 drawing units
wide. The command sequence would look like this:

Command: RECTANG
Specify first corner point or [Chamfer/Elevation/
Fillet/Thickness/Width]: (pick a point P1 anywhere or type
2,2)
Specify other corner point or [Dimensions]: D
Specify length for rectangles <0.0000>: 8
Specify width for rectangles <0.0000>: 5
Specify other corner point or [Dimensions]: (pick a point to fix the orientation)

 Selecting objects or Defining selection set
Introduction
Before you start to use the AutoCAD Modify commands, you need to know something about selecting
objects. All of the Modify commands require that you make one or more object selections. A selection
set can consist of a single object, or it can be a more complex grouping. You can create the selection set
either before or after you choose an editing command. You can make several changes to the same
selection set. AutoCAD has a whole range of tools which are designed to help you select just the objects
you need. This tutorial is designed to demonstrate the use of many of the selection options. As with so
many aspects of AutoCAD, developing a good working knowledge of these options can drastically
improve your drawing speed and efficiency.

Before you can edit objects, you need to create a selection set of the objects. Use one of the following
methods to create selection sets.
Selecting Objects by Picking/Pointing with mouse.
When you start a Modify command such as ERASE, two things happen. First, the cursor changes from
the usual crosshairs to the pickbox and second, you will see the "Select objects" prompt on the command
line. Both of these cues are to let you know that AutoCAD is expecting you to select one or more objects.

To select an object, place the pickbox
over a part of the object and left-click the
mouse. When the object has been
picked it is highlighted in a dashed line
to show that it is part of the current
selection and the command line
reports "1 found". You will now see the
"Select objects" prompt on the command line again. At this point you can continue adding more objects to
the current selection by picking them or you can press or the Space Bar to complete the selection.

Draw a circle using the CIRCLE command, the size and position of the circle does not matter.
Erase the Circle, Try yourself-Tutorial Tutorial

Erase the circle using the ERASE command, Modify Erase from the pull-down or from the
Modify toolbar.
Command: ERASE
Select objects: (place the pickbox over a circle circumference and left-click)
1 found
Select objects: (press to complete the selection and erase the object)

Creating selection sets by picking objects can become quite tedious if you want to select a large number
of objects. Just imagine having to pick a hundred or more objects in a large drawing. Fortunately
AutoCAD provides a number of selection options which can help you select objects more efficiently.

When you pick one or more objects in response to the "Select objects" prompt, you are effectively
creating a selection set. Selection sets are an important concept in AutoCAD because they can be used to
great effect, especially when drawings become large or complicated.
Window Selection/ Window or W, option
The Window option is invoked by typing W in response to the "Select objects" prompt. Window allows
you to define a rectangle using two points in exactly the same way as the RECTANGLE command. Once
the window is defined, all objects which lie entirely within the window will be selected.

First draw several circles of any size as shown in figure and than, start ERASE command,
Command: ERASE
Select objects: W
First corner: (pick first corner of selection window)
Specify opposite corner: (pick second corner of the selection window)
Select objects: (at this point you can either select more objects or to complete the selection
set and continue with the current command.)


Crossing Window Selection/Crossing or C option
The Crossing Window option is invoked by typing C at the "Select objects" prompt and is a variation
of the Window command, A crossing selection is displayed as dashed line. The command sequence is
exactly the same but objects are selected which lie entirely within the window and those which cross
the window border

The Undo option
It often happens that you inadvertently add objects which you don't want to a selection set during its
compilation. When this occurs in the middle of a complicated selection it can be pretty annoying.
Fortunately AutoCAD allows you to undo the last selection made during the compilation of a
selection set. All you need do is enter U at the next "Select objects" prompt to remove the objects
previously added.
Selects all objects /All option
The All option is invoked by typing ALL at the "Select objects" prompt. You can use this option to select
all the objects in the current drawing, no picking is required. Objects on Locked or Frozen layers are not
selected but objects on layers which are simply turned off are selected.

 Use of OBJECTSNAP/OSNAP to locate points [ F3 ]
Making drawings accurately

Introduction

Tools menu: Drafting Settings
Shortcut menu: Right-click Snap, Grid, Polar, Osnap, Otrack, or Dyn on the status bar and
click Settings.
Command entry: dsettings (or 'dsettings for transparent use)

The Object Snaps (Osnaps for short) are drawing aids which are used in conjunction with other
commands to help you draw accurately. Osnaps allow you to snap onto a specific object location when
you are picking a point. For example, using Osnaps you can accurately pick
the end point of a line or the center of a circle. Osnaps in AutoCAD are so
important that you cannot draw accurately without them. For this reason, you
must develop a good understanding of what the Osnaps are and how they
work. This tutorial describes the use of all the osnaps. There are a
number of worked examples which demonstrate Osnaps in use.

Using OSNAP through keyboard or OSNAP toolbar



ENDpoint
The Endpoint Osnap snaps to the end points of lines and arcs and to polyline vertices. This is one of
the most useful and commonly used Osnaps

Toolbar Object Snap
Pull-down Shift + Right Click Endpoint
Keyboard END (when picking)
.
MIDpoint
The Midpoint Osnap snaps to the mid points of lines and arcs and to
the mid point of polyline segments.

Toolbar Object Snap
Pull-down Shift + Right Click Midpoint
Keyboard MID (when picking)

INTersection
The Intersection Osnap snaps to the physical intersection of any two
drawing objects (i.e. where lines, arcs or circles etc. cross each other) and
to Polyline vertices.

Toolbar Object Snap
Pull-down Shift + Right Click Intersection
Keyboard INT (when picking)

CENter
The Center Osnap snaps to the centre of a circle, arc or polyline arc
segment. The cursor must pass over the circumference of the circle or the
arc so that the centre can be found.

Toolbar Object Snap
Pull-down Shift + Right Click Center
Keyboard CEN (when picking)

QUADrant
The Quadrant Osnap snaps to one of the four circle quadrant points located at north, south, east and
west or 90, 270, 0 and 180 degrees respectively.

Toolbar Object Snap
Pull-down Shift + Right Click Quadrant
Keyboard QUA or QUAD (when picking)

TANgent
The Tangent Osnap snaps to a tangent point on a circle. This osnap
works in two ways. You can either draw a line from a point to the tangent point (see illustration) or
you can draw a line from a tangent point, the latter is referred to as
the "Deferred Tangent" snap mode.


Toolbar Object Snap
Pull-down Shift + Right Click Tangent
Keyboard TAN (when picking)

PERpendicular
The Perpendicular Osnap snaps to a point which forms a perpendicular with the selected object. As
with the Tangent Osnap, Perpendicular can be used to draw a line to a perpendicular point, as in the
illustration or from a perpendicular point, known as the
"Deferred Perpendicular" snap mode.

Toolbar Object Snap
Pull-down Shift + Right Click Perpendicular
Keyboard PER or PERP (when picking)

PARallel
The Parallel Osnap is used to draw a line parallel to any other line in your drawing. In operation, this
osnap is slightly less intuitive than some of the others. To draw a parallel line, first start the Line
command, specify the first point when prompted and then start the Parallel Osnap. Hover the cursor
over an existing line until you see the Parallel snap marker. Now, move the cursor close to a parallel
position and a dotted line will appear, indicating the parallel. You can now pick the second point of
your line. The Snap Tip also includes a relative polar co-ordinate.

Toolbar Object Snap
Pull-down Shift + Right Click Parallel
Keyboard PAR or PARA (when picking)

 Exercises



 TRIM command
Modify toolbar:
Modify menu: Trim
Command entry: trim
Trims objects at a cutting edge defined by other objects

To trim an object
1. Click Modify menu » Trim.
2. Current settings: Projection = current Edge = current
Select cutting edges...
Select objects or <select all>: Select one or more objects to serve as cutting edges and press
ENTER, or press ENTER to select all displayed objects
3. Select object to trim or shift-select to extend or
[Fence/Crossing/Project/Edge/eRase/Undo]: Select the objects to trim.



 FILLET command
Filleting connects two objects with a smoothly fitted arc of a specified radius. Although in real world
an inside corner is called a fillet and an outside corner is called a round, AutoCAD treats both as
fillets.

Setting the Fillet Radius first
To set the fillet radius
1. From the Modify menu, choose Fillet.
2. Enter r (Radius).
3. Specify the fillet radius.
4. Press ENTER to reenter the FILLET command.
5. Select the objects to fillet.

 CHAMFER command
Chamfering connects two nonparallel objects by extending or trimming them to intersect or to join
with a beveled line. You can chamfer lines, polylines, xlines, and rays. With the distance method, you
specify the amount that each line should be trimmed or extended.
The chamfer distance is the amount each object is trimmed or extended to meet the chamfer line or to
intersect the other object. If both chamfer distances are 0, chamfering trims or extends the two objects
until they meet but does not draw a chamfer line.

The default setting for the first distance is the last distance specified. The default setting for the
second distance is whatever you choose for the first distance, because symmetrical distances are
common. However, you can reset the chamfer distances.
To chamfer by specifying distances

1. From the Modify menu, choose Chamfer or
2. Command line CHAMFER
3. Enter d (Distance).
4. Enter the first chamfer distance.
5. Enter the second chamfer distance.
6. Press ENTER to reenter the CHAMFER command.
7. Select the lines for chamfering.

 The Ellipse Command
Toolbar Draw
Pull-down Draw Ellipse Axis, End
Keyboard ELLIPSE short-cut EL

The Ellipse command gives you a number of different creation options. The default option is to pick the
two end points of an axis and then a third point to define the eccentricity of the ellipse. After you have
mastered the default option, try out the others.



Command: ELLIPSE
Specify axis endpoint of ellipse or [Arc/Center]: (pick P1)
Specify other endpoint of axis: (pick P2)
Specify distance to other axis or [Rotation]: (pick P3)

 OFFSET command

Offset creates a new object whose shape parallels the shape of a selected object. Offsetting a circle or an
arc creates a larger or smaller circle or arc, depending on which side you specify for the offset.
A highly effective drawing technique is to offset objects and then trim or extend their ends.

You can offset
 Lines
 Arcs
 Circles
 Ellipses and elliptical arcs
 2D polylines
 Construction lines (xlines) and rays
 Splines

To offset an object by specifying a distance
1. Click Modify menu » Offset.
2. Specify the offset distance.
You can enter a value or use the pointing device to specify the distance/gap
3. Select the object to offset.
4. Specify a point on the side where you want to place the new objects.
5. Select another object to offset, or press ENTER to end the command.

 Exercise – Oval Wash Basin (Assume missing dimensions, if any)


2dmuetcourse-110709082805-phpapp02.doc 35 of 66
 Exercise – Fancy Door (Assume missing dimensions, If any)

 The Rectangular Array
Toolbar Modify
Pull-down Modify Array
Keyboard ARRAY short-cut AR
The Array command makes multiple copies of selected objects in
a rectangular matrix (columns and rows) or a polar (circular) pattern.
The illustration on the right shows the results of a rectangular array
with two columns and three rows. The distance between rows is
indicated with the dimension DR and between columns with DC.
When creating rectangular arrays it is important to remember that new
rows are created above the original object and new columns are
created to the right of the original object. The resulting array is, therefore, always created with the original
object in the bottom left hand position with respect to the current co-ordinate system. In the illustration, the
original object is shown in dashed line and the new objects in continuous lines.
Note: It is possible to create arrays which do not align with the World Co-ordinate System by setting a User
Co-ordinate System first
atifkhan68@hotmail.com 0333-2642151 Page 35 of 66

Try creating this array yourself. First open a
new file with metric settings, draw a rectangle
20 drawing units wide and 10 drawing units tall
somewhere in the lower left quarter of the
drawing area.

Now start the Array command. First of all, make
sure that the Rectangular Array button is
selected and that you are looking at the
Rectangular Array dialogue box and now follow
the steps below:

1. Click the Select objects button. The
dialogue box will temporarily
disappear enabling you to select the rectangle you just drew. Press enter button on your keyboard to
complete the selection. You are now returned to the dialogue box and the message immediately below
the Select Objects button should read "1 objects selected".
2. Enter the number of rows required in the Rows edit box. For this example, enter the value "3". Notice
that the schematic preview on the right hand side of the dialogue box updates to reflect the values you
are entering.
3. Enter the number of columns required in the Columns edit box. Enter the value "2".
4. Enter the row offset in the Row Offset edit box. This is the distance DR as discussed earlier. Note that
is not the distance between rows. In this example, our rectangle is 1 units high and we will enter a row
offset of 15. The result will be a 5 unit gap between rows of rectangles.
5. Enter the column offset in the Column Offset edit box. The same parameters apply as for the row
offset. Enter a value of 25 to give a 5 unit gap between our rectangles.
6. Click on the Preview button. Once again, the dialogue box disappears and the specified array is
temporarily drawn so that we can preview it. We are now offered 3 choices. If the array isn't quite
right, click the Modify button to return to the Array
dialogue box. If you are happy with the array, click the
Accept button, the array will be permanently drawn and the
command is ended.
You should now have an array that looks similar to the one in the illustration above consisting of 6 rectangles
arranged in 3 rows and 2 columns. As you can se, this command is very powerful and can save lots of time if
used carefully.
Note: Try negative values specifying DR ( -15 ) & DC ( -25 ) in step no.4 & 5 , and see the different arrays
you get with such combinations.


 Exercise – Ventilation Panel
Complete the drawing of the ventilation panel. Use the Array command with the Rectangular option to create
a total of 8 rows and 5 columns.

 Exercise

 The Polar Array
The polar array works in a similar way to the rectangular array. The main difference is that rather than
specifying the number and offset for rows and columns, you must specify a center point and the total number
of objects in the array (including the original object).

You can try this for yourself by drawing another
rectangle as described above. This time, though, locate
the rectangle in the centre top half of the
drawing area. Now, start the Array command, click
the Polar Array button and follow the steps below:

1. Same as earlier
2. Specify the center point for the array. This is
the point C in the illustration below. You
can do this by entering x and y co-


ordinates into the appropriate edit boxes if you know what these values should be. However, this is
rarely the case and most often you will want to click the Pick Center Point button to pick a point from
the drawing area. Pick a point somewhere below the rectangle you have just drawn.
3. Enter a value for the total number of items. For this example, enter the value "6". Notice that once
again, the schematic preview updates to reflect the values you have entered.
4. Make sure that the Rotate items as copied checkbox is checked/selected
5. Same as step six in earlier
example
The array you have just drawn should look
something like the one illustrated below,
left. Take some time to play around with
the other options in the Array dialogue box to
see what they can do.
The illustration shows the results of a polar
array using an original rectangle copied six
times about a centre point C, through an angle
of 360 degrees. The only difference
between the array on the left and
the one on the right is that the Rotate items as copied checkbox was not checked in the right hand example.
All new objects created with the Array command will inherit the object properties of the original object.

 Exercises – Polar array

 Exercises (Door, Window & Chair)


 The Copy and Move Commands
With Copy command you can create Copies/duplicates of objects at a specified distance in a specified
direction


First start a drawing with imperial settings, draw the figure show below,

Command: Rectangle
Specify first corner point or
[Chamfer/Elevation/Fillet/Thickness/Width]: pick a point P1 anywhere
Specify other corner point or [Area/Dimensions/Rotation]: Type @2, 1 and press
enter

Now start Line command
Command: _line Specify first point: Select the lower left corner of rectangle P1
as start point of line
Specify next point or [Undo]: Select the upper right corner of rectangle P2
as end of line
Specify next point or [Undo]: Press enter to end the Line command

Start Circle command to draw the circle
Command: circle
Specify center point for circle or [3P/2P/Ttr (tan tan radius)]: Pick the mid point of the diagonal line
Specify radius of circle or [Diameter] <0.3126>: Type 0.25

To create a copy/duplicate of the rectangle at a gap of one inch from the previous rectangle.
Start Copy command by any one of the following methods

Command: copy
Select objects: Select the rectangle only
Select objects: Press enter to end selection
Specify base point or [Displacement] <Displacement>: Select lower left corner of the rectangle P1
Specify second point or <use first point as displacement>: Type @3, 0 and press enter
Specify second point or [Exit/Undo] <Exit>: (If you want to create more copies specify next location) But
now press enter to end copy command

With Move command you can move objects at a specified distance and direction from the originals.

The Move command works in a similar way to the Copy command except that no duplicate/copy is made, the
selected object(s) is simply moved/shifted from one location to another.

To move/shift the diagonal line and circle start move command by any one of the following methods,

Command: move
Select objects: Select the diagonal line
Select objects: Now select the circle
Select objects: Press enter to end move command
Specify base point or [Displacement] <Displacement>: Select the upper right corner P2 of the rectangle
Specify second point or <use first point as displacement>: Select upper right corner P3 of the copied rectangle
on the right side

 POINT Command
Points are very simple objects and the process of creating them is also very simple. Points are rarely used as
drawing components. They are normally used just as drawing aids in a similar way that Construction Lines
and Rays are used. When adding points to a drawing it is usually desirable to set the point style first because
the default style can be difficult to see.

The point command will insert a point marker in your drawing at a position which you pick in the drawing
window or at any co-ordinate location which you enter at the keyboard. The default point style is a simple dot,
which is often difficult to see but you can change the point style to something more easily visible or elaborate
using the point style dialogue box. You can snap to points using the Node object snap (You will learn this when
doing Object Snap tutorial for details)

Points can be used for "setting out" a drawing in addition to construction lines. You can Snap to points using
the Node object snap.

(Draw some points at various locations)
Command: POINT
Current point modes: PDMODE=0 PDSIZE=0.0000
Specify a point: (pick any point or type the coordinates where you
want to draw a point)


Strangely, in Multiple Point mode (the default for the Point button on the Draw toolbar) you will need
to use the escape key (Esc) on your keyboard to end the command. The usual right-click or enter
doesn't work.

You can start the point style command from the keyboard by
typing DDPTYPE or you can start it from the pull-down menu
at Format Point Style… The command starts by displaying a
dialogue box offering a number of options.

To change the point style, just pick the picture of the style you
want and then click the "OK" button. Any new points created
after the style has been set will automatically display in the new style.

One interesting aspect of points is that their size can be set to an absolute value or relative to the screen size,
expressed as a percentage. The default is for points to display relative to the screen size, which is very useful
because it means that points will remain the same size, irrespective of zoom factor. This is particularly
convenient when drawings become complex and the drawing process requires a lot of zooming in and out.

 The Construction Line Command
The Construction Line command creates a line of infinite length which passes through two picked points. Construction lines are very
useful for creating construction frameworks or grids within which to design.
Construction lines are not normally used as objects in finished drawings, it is usual, therefore,nto draw all your
construction lines on a separate layer which will be turned off or frozen prior to printing. Because of their nature,
the Zoom Extents command option ignores construction lines.

First open a new drawing using start from scratch with imperial settings, zoom out once and add/draw
some line using xline command,
Command: XLINE
Specify a point or [Hor/Ver/Ang/Bisect/Offset]: (pick a point anywhere or type 0,0)
Specify through point: (pick a second point anywhere or type 12,9)
Specify through point: (to end )

You may notice that there are a number of options with this command. For example, the "Hor" and
"Ver" options can be used to draw construction lines that are truly horizontal or vertical. In both these
cases, only a single pick point is required because the direction of the line is predetermined. To use a
command option, simply enter the capitalized part of the option name at the command prompt. Follow
the command sequence below to see how you would draw a construction line using the Horizontal
option.

 Exercise -



 The Polyline command
The Polyline or Pline command is similar to the line command except that the resulting object may be
composed of a number of segments which form a single object. In addition to the two ends a polyline is said to
have vertices (singular vertex) where intermediate line segments join. In practice the Polyline command works
in the same way as the Line command allowing you to pick as many points as you like. Again, just hit to
end. As with the Line command, you also have the option to automatically close a polyline end to end. To do
this, type C to use the close option instead of hitting .

You may be wondering, if Polylines are so useful, why bother using ordinary lines at all? There are a number of
answers to this question. The most frequently given answer is that because of their complexity, polylines use up
more disk space than the equivalent line. As it is desirable to keep file sizes as small as possible, it is a good idea
to use lines rather than polylines unless you have a particular requirement. You will also find, as you work with
AutoCAD that lines and polylines are operationally different. Sometimes it is easier to work with polylines for
certain tasks and at other times lines are best. You will quickly learn the pros and cons of these two sorts of line
when you begin drawing with AutoCAD.

Follow the command sequence below to see how this works. Polylines can also be given line widths to make
them appear solid. The figure shows a number of polylines to give you an idea of the flexibility of this type of
line.

Command: PLINE
Specify start point: (pick P1)
Current line-width is 0.0000
Specify next point or [Arc/Halfwidth/Length/Undo/Width]: (pick P2)
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: (pick P3)
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: (or C to close)

The figure on the left was created by hitting the key after the fifth point was picked. The figure on the right
demonstrates the effect of using the Close option. Try experimenting with options such as Arc and Width and
see if you can create polylines like the ones in the illustration above.



Polylines can be edited after they are created to, for example, change their width. You can do this using the
PEDIT command which will be discussed/taught later.

 The Donut Command
This command draws a solid donut shape. AutoCAD
asks you to define the inside diameter i.e. the diameter of
the hole and then the outside diameter of the donut. The
donut is then drawn in outline and you are asked to pick
the centre point in order to position the donut. You can
continue picking centre points to draw more donuts or
you can hit to end the command. Surprisingly,
donuts are constructed from single closed polylines composed of two arc segments which have been given a
width. Fortunately AutoCAD works all this out for you, so all you see is a donut.

First open a new imperial drawing file, and try this
Command: DONUT
Specify inside diameter of donut <0.5000>: (type 2 as inside/hole diameter)
Specify outside diameter of donut <1.0000>: (type 4 as outside diameter )
Specify center of donut or <exit>: (pick P1 anywhere or type 2,2)
Specify center of donut or <exit>: (to end or continue to pick for more donuts)
Curiously enough AutoCAD doesn't seem to mind if you make the inside diameter of a donut larger
than the outside diameter, try it and see.
 Exercise - Printed Circuit
Complete the printed circuit board. Use Donut with an inside diameter of 0.1 and an outside diameter of 0.2 to
create the pads. Use Pline with a width of 0.12 to complete the traces. Use a 0.25 Grid and Grid Snap to place all
pads (Donuts) on a point.


 The Polygon Command

The Polygon command can be used to draw any regular polygon from 3 sides up to
1024 sides. This command requires four inputs from the user, the number of sides, a
pick point for the centre of the polygon, whether you want the polygon
inscribed (Inside a circle) or circumscribed(Outside a circle) and then a pick point
which determines both the radius of this imaginary circle and the orientation of the
polygon. The polygon command creates a closed polyline in the shape of the required
polygon.

Command: POLYGON
Enter number of sides <4>: 5
Specify center of polygon or [Edge]: (pick P1 anywhere or type
12,0)
Enter an option [Inscribed in circle/Circumscribed about circle]
<I>: (to accept the inscribed default)
Specify radius of circle: (pick P2 anywhere or type 2 as a radius)

Specify center of polygon or [Edge]: (pick P1 anywhere or type 12,9)
Enter an option [Inscribed in circle/Circumscribed about circle] <I>: ( type C for
circumscribed)
Specify radius of circle: (pick P2 anywhere or type 2 as radius)

Command: POLYGON
Specify center of polygon or [Edge]: (type E to define by edge length)
Specify first end point of Edge: (pick P1 anywhere or type 6,4.5)
Specify first end point of Edge: (pick P2 or specify length by any method)


 Exercises

 The Arc Command
The Arc command allows you to draw an arc of a circle. There are
numerous ways to define an arc, the default method uses three pick
points, a start point, a second point and an end point. Using this
method, the drawn arc will start at the first pick point, pass through
the second point and end at the third point. Once you have mastered
the default method try some of the others. You may, for example need to draw an arc with a specific radius.
All of the Arc command options are available from the pull-down menu.

Command: ARC
Specify start point of arc or [Center]: (pick P1
anywhere)
Specify second point of arc or [Center/End]: (pick P2
anywhere)
Specify end point of arc: (pick P3)

Note: It is also possible to create an arc by trimming a circle object. In practice, many arcs are actually
created this way.
 Exercise – Drawing ARCS


 Exercise – Bath Tub



 ROTATE Command
First draw a figure similar to the one shown on right, or draw any other figure,
Start ROTATE command by using any one of the following methods

Command: _ROTATE
Current positive angle in UCS: ANGDIR=ccw ANGBASE=0
Select objects: Select Entities (Select the arrow only)
Specify base point: Select the point around which you will rotate the
entities.(Select the center of the circle)
Specify rotation angle or [Copy/Reference]: Enter angle (Type 120
degree angle & press enter)
 Loading different line types into drawing file using
Linetype Manager
Format menu: Linetype
Command entry: linetype (or 'linetype for transparent use)
Loads linetypes and sets the current linetype.
Load
Displays the Load or Reload Linetypes dialog box, in which you can load into the drawing selected
linetypes and add them to the linetype list.
Current
Sets the selected linetype to be the current linetype.
Delete
Deletes selected linetypes from the drawing. You can delete only unused linetypes. The BYLAYER,
BYBLOCK, and CONTINUOUS linetypes cannot be deleted.

 Exercises – Bed, Desktop Phone set & Slotted Flat Head Screw


 Creating & formatting Multiline / Paragraph text

Draw toolbar:
Draw menu: Text » Multiline Text
Command entry: mtext

To create multiline text
1. Click Draw menu » Text » Multiline Text.
2. Specify opposite corners of a bounding box to define the width of the multiline text object.
The In-Place Text Editor is displayed as shown above.
3. If you want to use a text style other than the default, click the arrow next to the Text Style control on the
toolbar and then select a style.
4. Enter text.
Note Text that would otherwise be difficult to read (if it is very small, very large, or is rotated) is displayed at
a legible size and is oriented horizontally so that you can easily read and edit it.

5. To override the current text style, select text as follows:
 To select one or more letters, click and drag the pointing device over the characters.
 To select a word, double-click the word.
 To select a paragraph, triple-click the paragraph.
6. On the toolbar, make format changes as follows:
 To change the font of the selected text, select a font from the list.
 To change the height of the selected text, enter a new value in the Height box.


 To format text in a TrueType font with boldface or italics, or to create underlined or overlined text for
any font, click the corresponding button on the toolbar. SHX fonts do not support boldface or italics.
 To apply color to selected text, choose a color from the Color list. Click Other to display the Select
Color dialog box.
7. To save your changes and exit the editor, use one of the following methods:
 Click OK on the toolbar.
 Click in the drawing outside the editor.
 Press CTRL+ENTER.

To insert symbols or special characters in multiline text
1. Double-click a multiline text object to open the In-Place Text Editor.
2. On the expanded toolbar, click Symbol.
3. Click one of the options on the menu, or click Other to display the Character Map dialog box.
To access the Character Map dialog box, you must have charmap.exe installed. See Microsoft® Windows®
Help for information about adding programs to your system.
4. In the Character Map dialog box, select a font.
5. Select a character, and use one of the following methods:
S To insert a single character, drag the selected character into the editor.
T To insert multiple characters, click Select to add each character to the Characters to Copy box. When
you have all the characters you want, click Copy. Right-click in the editor. Click Paste.
2.To save your changes and exit the editor, use one of the following methods:
T Click OK on the toolbar.
C Click in the drawing outside the editor.
Press CTRL+ENTER.
 The Mirror Command

The Mirror command allows you to mirror selected objects in your drawing
by picking them and then defining the position of an imaginary mirror
line using two points.

Try yourself
First create a figure similar to the shown above and use mirror command
Command: MIRROR
Select objects: (pick object to mirror, P1)
Select objects: (to end selection)
Specify first point of mirror line: (pick P2)
Specify second point of mirror line: (pick P3)
Delete source objects? [Yes/No] <N>: (for No to keep the original
object)
Notice that in the command sequence above, pressing the key when
asked whether to "Delete source objects?" resulted in a "No" response.
This is because "No" is the default option. AutoCAD always shows the default option within triangular

brackets, in this case "<N>". Many AutoCAD commands offer default options. They are usually the most
commonly used and you need only right-click and select "Enter" from the menu or press on the keyboard to
accept them.
In order to create perfectly horizontal or vertical mirror lines use Ortho.

 Exercise – Mirror the Pulley
Draw one side of the pulley shown in Figure. Use the Mirror command to complete the other side, Save the
drawing as PULLEY.

 Exercise – Mirror the elevation
Practice drawing half of the figure shown below and than use mirror command to create the opposite half.
Assume any appropriate dimensions/sizes.

 Creating Layers, using Layer manager dialogue box-Tutorial
Object
Create following layers, assign color and line type to each
layer by using the layer and line type properties dialogue box.
Introduction
Layers are like transparent overlays on which you organize and
group different kinds of drawing information. The objects you
create have common properties including colors, Linetypes, and
lineweights. An object can assume these properties from the
layer it is drawn on, or properties can be specifically assigned to
individual objects. Color helps you distinguish similar elements in your drawings, enhancing your drawing


and increasing legibility. Organizing layers and the objects on layers makes it easier to manage the
information in your drawings.

You can assign properties to layers as well as to
individual objects in a drawing. If you want a
specific object to have a different color, Linetype,
lineweight than the layer it is drawn on, you can
change the object property setting.

Common layers mostly used in drawings are walls,
doors, windows, plumbing, electrical, fixtures,
structural elements, notes (text), dimensions, ceiling,
insulation, posts, title block, center, hidden, hatch, object and so on.
Procedure
The formation of layers in a drawing involves the following steps.
First open a new drawing file using start from scratch and imperial settings. Give it a name (Layer practice) by
using Save as option in the file menu.
Creating and Naming Layers
Use any one of the following methods to display the Layer properties manager dialog as shown.
Layers toolbar:
Format menu: Layer
Command entry: layer (or 'layer for transparent use or –layer to avoid dialogue box)
Listed in the box is only one layer which is default Layer. Generally drawings are not created on 0
layer, instead it should be created on newly created layers. To create these Layers, click on the “New
Layer” button and notice a layer is automatically added to the list of layers. This layer is given a
default name “Layer 1” but you can type Object here as this is the layer which we want to create.
Pressing/Typing/Entering a comma at the end of the layer’s name, allows more layers to be added to
the list of layers. Once the comma was entered after the layer “Object” and the new layer appears,
enter the new name of the layer as “Hidden”. Repeat this procedure of using comma to create other
desired layers. The layer listing will be as shown above in figure except the circle on the color swatch.


Autocade 2D complete course

Recomendados

Recomendados

Mais conteúdo relacionado

Mais procurados

Mais procurados (20)

Semelhante a Autocade 2D complete course

Semelhante a Autocade 2D complete course (20)

Mais de Mohammad Younus

Mais de Mohammad Younus (20)

Último

Último (20)

Autocade 2D complete course