AUTOCAD

AUTOCADAUTOCAD Basic CommandsLineCircleRectangleArcPolygonSplineEllipseHatch (BHatch)

Invoke the line Command

Option for Line CommandThe LINE command has the following three options.

Continue

Close

Undo

The Continue Options The Continue option enables you to grab the endpoint of the previous line and to continue drawing the line from that point.

Use : Enter / right-click / @The Close Options The Close option is used to join the current point with the initial point of the first line when two or more lines are drawn in continuation.

This option is used when an open figure needs one more line to close it and make a polygon.

The Undo OptionsIf you draw a line, and then realize that you made an error, you can remove the line.

using the undo option.

If you need to remove more than one line, you can use this option multiple times and go as far back as you want.

Use : U / Undo from shortcut menu.Concept of Cartesian Coordinate SystemAbsolute Coordinate System

Relative Coordinate System

Polar Coordinate System

Cartesian Coordinate System

Any entities place on the working two dimensional plane can be defined relative to the Cartesian coordinate system.

The Cartesian coordinate system divides a two dimensional plane with two perpendicular axis.

The X axis runs horizontal across the bottom of the screen. The Y axis runs vertically along the left side of the screen.

9Absolute, Relative Rectangle & Polar Coordinate System

Direct Distance EntryYou can draw a line by specifying the length of the line and its direction, using direct distance entry.

The direction is determined by the position of the cursor, and the length of the line is entered from the keyboard.

Command : Line Specify first point : Start Point.Specify next point or [Undo] :Position the cursor and then enter the distance.Specify next point or [Undo] :Position the cursor and then enter the distance.

Draw Lines using Different Methods

Draw Lines using Different Methods

Draw Lines using Different Methods

Lab Task Draw the object shown using Absolute, Relative Rectangular, or relative polar coordinate system.

Construction LineThis is continuous Line and extending to Identify from both side.

To activate this Type xline in command windowIcon of construction line in Draw Toolbar

Circle

Options of Circle commandThe Center and Radius Option.

The Center and Diameter Option.

The Two-Point Option.

The Three-Point Option.

The Tangent Tangent Radius Option.

The Tangent, Tangent, Tangent Option.

The Center and Radius OptionHow to Proceed:

Type/ select Circle >> Enter >> Specify starting point >> Enter Type the radius of the circle.

Example CIRCLE 3,2 1 The Center and Diameter OptionCIRCLE 2,3 D 2 The Two-Point OptionIn this option, AutoCAD lets you draw the circle by specifying the two endpoints of the circles diameter

e.g., CIRCLE 2P 1,1 2,1

The Three-Point OptionThe circle can also be drawn by defining three points on the circumference of the circle e.g.,

CIRCLE 3P 3,3 3,1 4,2

You can also use relative rectangular coordinates to define the points e.g.,

CIRCLE 3P 3,3 @0,-2 @1,1

The Tangent Tangent Radius Option The tangent is an object ( line, circle, or arc ) that contacts the circumference of a circle at only one point.This option is used to locate two tangent points on the selected objects that are to be tangents to the circle.

CIRCLE T select first line, circle, or arc. select second line, circle, or arc. Radius of circle

The Tangent Tangent TangentOption This option is used to locate three points on the selected objects to which the circle is drawn tangent.CIRCLE Select Tan, Tan, Tan option from the DRAW menu select the first object select the second object select the third object

Lab Task

Lab Tak

Drawing Arcs and RectanglesDraw an Arc :

Type arc in command window Menu : Draw > Arc The default method for drawing arc is the 3 point option.

Draw a Rectangle :

Type Rectangle in command window specified starting point d type length type width Menu : Draw > Rectangle

Options of RectangleChamfer : Angled Corners

Fillet : rounded corners

Width : width of line segments

Thickness : rectangle extruded in z direction

Elevation : rectangle at a specified distance from the XY plane along z axis.

Drawing PolygonA regular polygon is a close geometric figure with equal angles. The number of sides vary from 3 to 1024 e.g., a triangle is a three-sided polygon and a pentagon is a five-sided polygon.

How to Proceed:

Select / Type Polygon in command window Once you invoke the polygon command, it prompts you to enter the number of sides. e.g 8After you specify the number of sides, the next prompt is Specify center of polygon or [Edge]. e.g 5 (for edge you pressed E)The next prompt is Enter an option [ Inscribed in circle/ Circumscribed about circle]. (Use I for Inscribed and C for Circumscribed.After this enter the radius of the circle e.g enter 5 Drawing PolygonA polygon is said to be inscribed when it is drawn inside an imaginary circle and its vertices (corners) touch the circle. Likewise, a polygon is circumscribed.

When it is draw outside the imaginary circle and side of the polygon are tangents to the circle (midpoint of each side of the polygon will lie on the circle

Drawing Polygonpolygon 6 E 2,4 2,2.5 The polygon is drawn in a counterclockwise direction, with the two points entered defining its first edge.

Drawing PolygonCircle enter the radius 5 Select Polygon 8 sided specify the center point of circle Enter I for inscribed circle select the radius of the circle that is 5.

32Drawing EllipsesIf a circle is observed from an angle, the shape seen is called an Ellipse, which can be created in AutoCAD using the Ellipse command. Menu : Draw > EllipseMajor and Minor axis control the size of the ellipse.

ellipse 3,3 6,3 1

ellipse 3,3 4,2 2

Drawing an Ellipse using the axis and Endpoint optionellipse 3,3 6,3 1

ellipse 3,3 4,2 2

Drawing an Ellipse using the axis and Endpoint optionellipse 3,3 6,3 R 0

ellipse 3,3 6,3 R 80

Note: When you enter R (rotation), the first axis specified is automatically taken as the major axis of the ellipse. The next prompt is Specify rotation around major axis. The major axis is taken as the diameter line of the circle, and the rotation takes place around this diameter line into the third dimension. The ellipse is formed when AutoCAD projects this rotated circle into the drawing plane.

Drawing an Ellipse using the center and two axesellipse C 4,4 6,4 1

The center of an ellipse is defined as the point of intersection of the major and minor axes..

Drawing Elliptical ArcsMenu : Draw > Ellipse > Arc

Hatch It is a way of filling in areas of your drawing with a pre-formatted pattern to represent certain materials.It is usually used in sectional views.

How to Proceed:

Draw >> select HatchType Hatch in command windowSelect the object which is being hatched Select the Hatch type