AUTOCAD

AutoCAD

INTERFACE: 

MANU BAR:

Display pull-down menus from the menu bar using one of several methods. You can also specify alternate menus.

DRAWING AREA:

The area in which your drawings are displayed and modified. The size of the drawing area varies, depending on the size of the AutoCAD window and on how many toolbars and other elements are displayed

CURSOR:

A type of cursor consisting of two lines that intersect.

UCS:

                  A user-defined coordinate system that defines the orientation of the X, Y, and Z axes in 3D space. The UCS determines the default placement of geometry in a drawing. See also world coordinate system (WCS).
  

TOOL BAR:

                                      Part of the interface containing icons that represent commands.

 WAYS TO START A DRAWING:

When you start AutoCAD, the Startup dialog box is displayed. The dialog box provides you with four ways to start a drawing. You can
1.Open an existing drawing
2.Start a drawing from scratch
3.Start a drawing based on a template
4.Use wizards to help you set up your drawing

OPEN A DRAWING:

                                             Opens a drawing you select from a list of the four most recently opened drawings. Also, displays the Browse button that you choose to look for another file. 

START FROM SCRATCH:

                  Opens a new drawing based on the measurement system you choose English (inches) or metric (millimeters).1In the Startup dialog box, choose Start from Scratch. (If
AutoCAD is already started, from the File menu, choose
New, and then choose Start from Scratch in the Create New Drawing dialog box.)
2Select English or Metric, and then choose OK.
The drawing opens based on the English (acad.dwt) or metric (acadiso.dwt) template and with the name drawing1.dwg.
3 From the File menu, choose Save As.4 In the Save Drawing As dialog box under File Name, enter a name for the drawing and choose Save.

USE A TEMPLATE:

                        Opens a new drawing based on a template you select from a list. The list displays template files (.dwt extension) that exist in the drawing template file location as specified in the Options dialog box. Template files store all the settings for a drawing and can also include predefined layers, dimension styles,
  1          In the Startup dialog box, choose Use a Template. (If AutoCAD is already started, from the File menu, choose New, and then choose Use a Template in                  the Create New Drawing dialog box.)
2           Under Select a Template, select a template from the list or choose Browse to select another file.     
        A preview image of the template appears at the right, and a description appears near the bottom of the dialog box.
3            Choose OK.

                AutoCAD opens the drawing as drawing. dwg. 

USE A WIZARD:

                        Opens a new drawing that you set up using either the Quick Setup wizard or the Advanced Setup wizard.
 1       In the Startup dialog box, choose Use a Wizard. (If AutoCAD is already started, from the File menu, choose New, and then choose Use a Wizard in the                   Create New Drawing dialog box.) 
2         Under Select a Wizard, select Quick Setup or Advanced Setup and choose OK.
3         Complete the wizard pages using the Next and Back buttons to move forward and backward.
  4         On the last page choose Finish.To turn off display of the Startup dialog box

In the Startup dialog box, clear Show Startup Dialog.

TO TURN OFF DISPLAY OF THE STARTUP DIALOG BOX:

In the Startup dialog box, clear Show Startup Dialog. 

 TO DISPLAY THE STARTUP DIALOG BOX:

1   From the Tools menu, choose Options.
2   In the Options dialog box, choose the System tab.
3   3   Under General Options, select Show Startup Dialog. 4   Choose OK.                To display or close toolbars
1    Right-click the background or title bar of any displayed toolbar, such as the Standard or Draw toolbar.
  2    From the shortcut menu, select the toolbar you want to display or close.Command line TOOLBAR displays the Toolbars dialog box, in which you can turn toolbars on and off and customize toolbars. See "Modifying

Toolbars."

You can display multiple toolbars at once, and you can dock or float toolbars. Docked toolbars lock into place along the top, bottom, or sides of the AutoCAD window. Floating toolbars move freely; move them using your pointing device. Floating toolbars can overlap other floating and docked toolbars. You can also hide toolbars until you need them.  

TO DOCK OR UNDOCK A TOOLBAR:

1       To dock a toolbar, place your pointer on the background or title bar of the toolbar, then use your pointing device to drag the toolbar to a dock location at                  the  top, bottom, or either side of the drawing window.
  2          When the outline of the toolbar appears in the docking area you want, release the pointing device button.
3         To undock a toolbar, drag it outside the docking region.
4         To place a toolbar in a docking region without docking it, hold down CTRL as you drag.
To change the shape of a floating toolbar
Drag the bottom border of a floating toolbar to create a vertical toolbar.
or
Drag the side border of a floating toolbar to create a horizontal toolbar.
or
Drag the border of a floating toolbar to reshape.

When you start AutoCAD, the Startup dialog box is displayed. The dialog box provides you with four ways to start a drawing. You can
Open an existing drawing
Start a drawing from scratch
Start a drawing based on a template
Use wizards to help you set up your drawing
Open a Drawing: Opens a drawing you select from a list of the four most recently opened drawings. Also, displays the Browse button that you choose to look for another file.
Start from Scratch: Opens a new drawing based on the measurement system you choose—English (inches) or metric (millimeters).
Use a Template: Opens a new drawing based on a template you select from a list. The list displays template files (.dwt extension) that exist in the drawing template file location as specified in the Options dialog box . Template files store all the settings for a drawing and can also include predefined layers, dimension styles,
Use a Wizard: Opens a new drawing that you set up using either the Quick Setup wizard or the Advanced Setup wizard.

Units
Indicates the format in which you enter and in which AutoCAD displays coordinates and measurements. Several formats are available in AutoCAD. Two of them, Engineering and Architectural, have a specific base unit (inches) assigned to them. You can select from other measurement styles that can represent any convenient unit of measurement.
Note: You control the precision (the number of decimal places displayed in all measurements) by using the Advanced Setup wizard or the UNITS command. The default precision used by Quick Setup is four (0.0000).
DecimalDisplays measurements in decimal notation.
EngineeringDisplays measurements in feet and decimal inches.
ArchitecturalDisplays measurements in feet, inches, and fractional inches.
FractionalDisplays measurements in mixed-number (integer and fractional) notation.
ScientificDisplays measurements in scientific notation (numbers expressed in the form of the product of a decimal number between 0 and 10 and a power of 10).

UNITMODE system variable    Controls the display format for units. 

0 Displays fractional, feet-and-inches, and surveyor's angles as previously set 1 Displays fractional, feet-and-inches, and surveyor's angles in input format
To turn off display of the Startup dialog boxIn the Startup dialog box, clear Show Startup Dialog.
To display the Startup dialog box
1        From the Tools menu, choose Options. 
2       In the Options dialog box, choose the System tab.
3       Under General Options, select Show Startup Dialog.
4       Choose OK.

To open a drawing 

1            In the Startup dialog box, choose Open a Drawing, and then choose Browse. (If AutoCAD is already started, from the File menu, choose Open.)
2              In the Select File dialog box, select one or more files and choose Open.
  
You can also enter the drawing name under File Name and choose Open, or double-click a file name in the list of files.

To create a new drawing using Start from Scratch

 

1    In the Startup dialog box, choose Start from Scratch. (If AutoCAD is already started, from the File menu, choose New, and then choose Start from Scratch in          the Create New Drawing dialog box.) 
2    Select English or Metric, and then choose OK.
       The drawing opens based on the English (acad.dwt) or metric (acadiso.dwt) template and with the name drawing1.dwg. 
3      From the File menu, choose Save As.
4     In the Save Drawing As dialog box under File Name, enter a name for the drawing and choose Save.
  

To start a drawing using a template

1        In the Startup dialog box, choose Use a Template. (If AutoCAD is already started, from the File menu, choose New, and then choose Use a Template in the             Create New Drawing dialog box.)  2       Under Select a Template, select a template from the list or choose Browse to select another file.
A preview image of the template appears at the right, and a description appears near the bottom of the dialog box.
3 Choose OK.
AutoCAD opens the drawing as drawing.dwg.

To start a drawing using a wizard 

1   In the Startup dialog box, choose Use a Wizard. (If AutoCAD is already started, from the File menu, choose New, and then choose Use a Wizard in the Create         New Drawing dialog box.) 

2   Under Select a Wizard, select Quick Setup or Advanced Setup and choose OK.

3   Complete the wizard pages using the Next and Back buttons to move forward and backward.
 
4   On the last page choose Finish.

To turn off display of the Startup dialog box
In the Startup dialog box, clear Show Startup Dialog.

                                                              Basic AutoCAD Terminology 

Here are some basic terms that you will need to know to begin using AutoCAD

 

ABSOLUTE COORDINATE SYSTEM

Absolute Cartesian coordinate system has three axes: X, Y, and Z. When you enter coordinate values, you indicate a point's
distance (in units) and its direction (+ or –) along the X, Y, and Z axes relative to the coordinate system origin (0,0,0)

RELATIVE COORDINATE SYSTEM

Relative Cartesian coordinate system has three axes: X, Y, and Z. When you enter coordinate values, you indicate a point's distance (in units) and its direction (+ or –) along the X, Y, and Z axes relative to previous point.

POLAR COORDINATE SYSTEM

Polar coordinate systems use a distance and an angle to locate a point. When you enter polar coordinate values, you indicate a point's distance from the origin

POLAR RELATIVE COORDINATE SYSTEM

Polar Relative coordinate systems use a distance and an angle to locate a point. When you enter polar coordinate values, you indicate a point's distance the previous point and its angle along the XY plane of the current coordinate system.

DIRECT DISTANCE ENTRY

In addition to entering coordinate values to specify points, you can use a method called direct distance entry. You can use this feature during any of the drawing commands. Once you have started the command and specified the first point, you can specify a point by moving the cursor to indicate a direction and then entering the distance from the first point. This is a good way to specify a line length quickly and is especially useful used in conjunction with ortho and polar tracking.
You can use direct distance entry to specify points for all commands except those that prompt you to enter a single real value, such as ARRAY, MEASURE, and DIVIDE. When Ortho is on, this method is an efficient way to draw perpendicular lines..

The X,Y co-ordinate system
Everything that you draw in AutoCAD is exact. It will be more accurate than you will ever need it to be. All objects drawn on the screen are placed there based on a simple X,Y co-ordinate system. In AutoCAD this is known as the World Co-ordinate System(WCS). You must understand this to know how to put things where you want them. (3-D work has an added axis, the Z-axis, but this is not covered in this lesson.) Below is a diagram showing you how this system works (place your mouse on the diagram for more info). 

In order to work effectively with AutoCAD, you have to work with this system. Until you are comfortable and familiar with it, learning AutoCAD will be more of a chore. My experience in teaching is that the better a student is with co-ordinates, the better CAD draftsperson they are.
Here is how it works:
AutoCAD uses points to determine where an object is located. There is an origin where it begins counting from. This point is (0,0). Every object is located in relation to the origin. If you were to draw a line straight out to the right from the origin, this would be considered the positive X-axis. If you were to draw a line straight up, this would be the positive Y-axis. The picture above shows a point located at (9,6). This means that the point is 9 units over in the X-axis and 6 units up in the Y-axis. When you are working with points, X always comes first. The other point shown is (-10,-5). This means that the point is 10 units in the negative X-axis (left) and 5 units in the negative Y-axis (down).

A line has two points, a start point and an end point. AutoCAD works with the points to display the line on the screen. Move your cursor over the picture above and you will see line drawn from the absolutepoints of (-10,-5) to (9,6). Most of the time you will not have an indication of where the origin is. You may need to draw a line from the endpoint of an existing line. To do this you use relativepoints.
These work the same way, but you have to add the @ symbol (shift+2) to tell AutoCAD that this next point is relative from the last point entered.
Its a simple system, but mastering it is the key to working with AutoCAD and is explained below.