AutoCAD Practical Manual

F.E

.

By Prof.Shaikh Ibrahim Ismail

Automobile Engg. Dept., MHSSCE 2011-2012

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

2

PURPOSE & OBJECTIVES

This courseware is for novice users of AutoCAD. It covers the fundamentals of AutoCAD to make the students of first year of Engineering familiar with AutoCAD software and its use . The course ware demonstrates in a very simple step-by-step procedure how to create an engineering drawing, modify it, annotate it, dimension it, and finally print it. This courseware will make the students to:

Understand AutoCAD and how to deal with its basic operations includingits fi ling

system Draw different objects quickly and precisely Set up drawings Construct drawings in a few simple steps Modify any object in a drawing Create, insert, and edit blocks Hatch using different hatch patterns and methods Create text and tables Insert and edit dimensions Prepare and plot a drawing

This courseware is complied for only educational Purpose.

Prof.Shaikh Ibrahim Ismail Automobile Engineering Department

M.H.Saboo Siddik College of Engineering Mumbai-400008.

AutoCAD Practical Manual

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AutoCAD Practical Manual

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Table of Content

NO. TITLE PAGE

1 Introduction to AutoCAD

5-6

2 Basic Draw Commands

7-11

3 Basic Modify Commands

12-16

4 Standard Tools

17-24

5 Exercise 01

25-26

6 Exercise 02 27-28

7 Exercise 03

29-30

8 Exercise 04 31-32

9 Sample 33-34

10 Short cut Keys 35

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Chapter 1 1.1 Introduction to AutoCAD

AutoCAD is a computer aided drafting software package used by Millions of engineers, draftsmen,

project managers, engineering students, and anyone dealing with drawings on daily basis

AutoCAD is a software program, created in 1982 for 2D and 3D design and drafting. This program runs on personal computers on Microsoft Windows desktop. AutoCAD is available in several different languages and can translate as well. There are several different versions of AutoCAD. The first version is AutoCAD LT, this is a version of AutoCAD with limited capabilities. This version only has 2D capabilities and it is available at most computer stores. AutoCAD LT is perfect for beginners or entry-level users. AutoCAD has a few different types of file formats. DWG is their most used file format. Two of the other file formats are DXF and DWF. DXF has become a standard for CAD data and DWF which was developed by Autodesk but is used in the recent versions of AutoCAD. Each project is saved based on what is in the design. 1.2 Opening AutoCAD Open up AutoCAD, you should be greeted with a screen asking if you want to open an existing drawing or start from scratch. (Dependant on your version of AutoCAD, the screen will be slightly different

Arrange the icons to where is comfortable for you (A typical layout is shown above)

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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1.3 Toolbars There are many toolbars available in AutoCAD. Go to View > Toolbars from the drop down menu to see them all. Make sure that the following toolbars are checked: Draw - Contains AutoCAD’s most common drawing tools Modify - Contains all of the common editing commands such as erase, copy etc. Object Properties - Contains 'layer' information as well as object colours and line style options Standard Toolbar - Contains open & save options as well as zoom & pan options. Object Snap - AutoCAD's intelligent drawing aid - joins lines at specific points. Start, Organize, and Save a Drawing Start a Drawing

Start a Drawing from Scratch

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.You can start from scratch from the Create New Drawing dialog box, from the Select Template dialog box, or without using a dialog box at all. In each case, you use either the NEW command or the QNEW command.

DRAWING LIMITS AutoCAD offers the user an infi nite drawing sheet on all sides.

When you start a new AutoCAD drawing, your viewpoint will be at 0,0,1.

You look at the XY plane using a camera’s lens; hence, you will see part of your infinite drawing

sheet. This part is called the limits.

THINGS YOU SHOULD KNOW ABOUT AUTOCAD

The mouse is the primary input device.

The left mouse button is always used to select as well as to click.

The right mouse button, when clicked, offers a drop-down menu.

If you type an AutoCAD command or any input in the Command Window you have to press [Enter] key to execute it.

[Enter] = [Spacebar] in AutoCAD.

To repeat the last AutoCAD command, press [Enter] or [Spacebar].

To cancel any AutoCAD command, press [Esc].

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Chapter 2 Basic Draw Commands 1-LINE : Creates straight line segments

Enter Line in command line .

Specify the start point.

You can use the pointing device or enter coordinate values at the command prompt.

Complete the first line segment by specifying the endpoint. To undo the previous line segment during the LINE command, enter u or click Undo on the toolbar.

Specify the endpoints of any additional line segments.

Press ENTER to end or c to close a series of line segments.

To start a new line at the endpoint of the last line drawn, start the LINE command again and press ENTER at the Specify Start Point prompt.

Toolbar: Draw

Command entry: LINE 2- RAY :Creates a line that starts at a point and continues to infinity

At the command prompt, enter xline.

Specify a point to define the root of the construction line.

Specify a second point through which the construction line should pass.

Continue to specify construction lines as needed. All subsequent xlines pass through the first point specified.

Press ENTER to end the command.

Toolbar: Draw

Command entry: XLINE 3- XLINE : Creates a line of infinite length

At the command prompt, enter ray.

Specify a starting point for the ray.

Specify a point through which the ray should pass.

Continue to specify points to create additional rays as needed.

All subsequent rays pass through the first point specified.

Press ENTER to end the command.

Command entry: RAY 4- Polylines: A polyline is a connected sequence of segments created as a single object. You can create straight line segments, arc segments, or a combination of the two. PLINE : Creates a 2D polyline

At the command prompt, enter pline.

Specify the first point of the polyline.

Specify the endpoint of the first polyline segment.

Continue specifying segment endpoints as needed.

Press ENTER to end, or enter c to close the polyline.

To start a new polyline at the endpoint of the last polyline drawn, start the PLINE command again and press ENTER at the Specify Start Point prompt.

Toolbar: Draw

Command entry: PLINE 5- Rectangles and Polygons: create rectangles and regular polygons quickly RECTANGLE : creates closed polylines in a rectangular shape.

At the command prompt, enter rectang.

Specify the first corner of the rectangle.

Specify the other corner of the rectangle.

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Toolbar: Draw

Command entry: RECTANG POLYGON : creates closed polylines with between 3 and 1,024 equal-length sides. a-To draw a circumscribed polygon

At the command prompt, enter polygon.

At the command prompt, enter the number of sides.

Specify the center of the polygon (1).

Enter c to specify a polygon circumscribed about a circle.

Enter the radius length (2). b- To draw an inscribed polygon

At the command prompt, enter polygon.

At the command prompt, enter the number of sides.

Specify the center of the polygon.

Enter i to specify a polygon inscribed within a circle of specified points.

Enter the radius length.

Toolbar: Draw

Command entry: POLYGON

6-ARC : Creates an arc .To create an arc, you can specify various combinations of center, endpoint, start point, radius, angle, chord length, and direction values.

To draw an arc by specifying three points

At the command prompt, enter arc.

Specify the start point.

Specify a point on the arc.

Specify the endpoint.

Toolbar: Draw

Command entry: ARC

7- CIRCLE :Creates a circle. To create circles, you can specify various combinations of center, radius, diameter, points on the circumference, and points on other objects.

To draw a circle by specifying a center point and radius or diameter

Do one of the following:

Click Home tab Draw panel Center, Radius.

Click Home tab Draw panel Center, Diameter.

Specify the center point.

Specify the radius or diameter.

Toolbar: Draw

Command entry: CIRCLE

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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8- Ellipses: Creates an ellipse or an elliptical arc

To draw a true ellipse using endpoints and distance

1. Enter ellipse at the command prompt. 2. Specify the first endpoint of the first axis (1). 3. Specify the second endpoint of the first axis (2). 4. Drag the pointing device away from the midpoint, and click to specify a distance (3) for half the

length of the second axis.

Toolbar: Draw

Command entry: ELLIPSE 9- Splines : Creates a smooth curve that passes through or near specified points

To convert a spline by specifying points

At the command prompt, enter spline.

Specify the start point for the spline (1).

Specify points (2 through 5) to create the spline, and press ENTER.

Specify the start and end tangents (6, 7).

Toolbar: Draw

Command entry: SPLINE

10- Regions: Converts an object that encloses an area into a region object

a-To define regions

At the command prompt, enter region.

Select objects to create the region. These objects must each form an enclosed area, such as a circle or a closed polyline.

Press ENTER. A message at the command prompt indicates how many loops were detected and how many regions were created.

Command entry: REGION

b- To combine regions by adding

At the command prompt, enter union.

Select one region for the union.

Select another region. You can select regions to unite in any order.

Continue selecting regions or press ENTER to end the command. The command converts the selected regions to a new combined region.

Command entry: UNION

c-To combine regions by subtracting

At the command prompt, enter subtract.

Select one or more regions from which to subtract and press ENTER.

Select the region to subtract and press ENTER. The areas of the second regions you selected are subtracted from the areas of the first regions.

Command entry: SUBTRACT

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Hatch Patterns and Fills 11-HATCH :Fills an enclosed area or selected objects with a hatch pattern, solid fill, or gradient fill.

Click Home tab Draw panel Hatch. At the command prompt, enter hatch.

In the Hatch and Gradient dialog box, click Add: Pick points.

In your drawing, specify a point inside each area that you want hatched, and then press ENTER.

This point is known as the internal point.

In the Hatch and Gradient dialog box, Hatch , in the swatch box, verify that the sample pattern is the pattern you want to use. To change patterns, select another pattern from the Pattern list.

In the Hatch and Gradient dialog box, make adjustments, if necessary.

Under Draw Order, click one of the options. You can change the draw order of the hatch so that the hatch is drawn either behind or in front of the hatch boundary, or behind or in front of all other objects.

Click OK.

Toolbar: Draw

Command entry: HATCH

12- multiline text :Creates a multiline text object

Click Home tab Annotation panel Multiline Text.

Specify opposite corners of a bounding box to define the width of the multiline text object. If the ribbon is active, the MTEXT ribbon contextual tab displays. If the ribbon is not active, the In-Place Text Editor is displayed.

To indent the first line of each paragraph, drag the first-line indent slider on the ruler. To indent the other lines of each paragraph, drag the paragraph slider.

To set tabs, click the ruler where you want a tab stop.

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.

Enter text. NoteText 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.

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.

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. NoteThe MText height value is reset to 0 if its default height is not modified during

creation. 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.

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.

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Press CTRL+ENTER.

Toolbar: Draw Command entry: MTEXT

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Chapter 3 Basic Modify Commands 1- ERASE: Removes objects from a drawing

a- To erase an object

Click Home tab Modify panel Erase.

At the Select Objects prompt, use a selection method to select the objects to be erased or enter an option:

Enter L (Last) to erase the last object drawn. Enter p (Previous) to erase the last selection set. Enter all to erase all objects from the drawing. Enter ? to see a list of all selection methods.

Press ENTER to end the command.

Toolbar: Modify

Command entry: ERASE 2- COPY :Copies objects a specified distance in a specified direction

To copy an object using two points

Click Home tab Modify panel Copy.

Select the objects to copy.

Specify the base point.

Specify the second point. Press ENTER.

Toolbar: Modify

Command entry: COPY 3- MIRROR : Creates a mirrored copy of selected objects

To mirror objects

Click Home tab Modify panel Mirror.

Select the objects to mirror.

Specify the first point of the mirror line.

Specify the second point.

Press ENTER to retain the original objects, or enter y to erase them.

Toolbar: Modify

Command entry: MIRROR 4- OFFSET: Creates concentric circles, parallel lines, and parallel curves

To offset an object by specifying a distance

At the command prompt, enter offset.

Specify the offset distance.

You can enter a value or use the pointing device.

Select the object to offset.

Specify a point on the side where you want to place the new objects.

Select another object to offset, or press ENTER to end the command.

Toolbar: Modify

Command entry: OFFSET

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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5- ARRAY :Creates multiple copies of objects in a pattern

a-To create a rectangular array

Click Home tab Modify panel Array.

In the Array dialog box, select Rectangular Array.

Click Select Objects.

The Array dialog box closes. You are prompted for object selection.

Select the objects to be arrayed and press ENTER.

In the Rows and Columns boxes, enter the number of rows and columns in the array.

Specify the horizontal and vertical spacing (offsets) between objects by using one of the following methods:

In the Row Offset and Column Offset boxes, enter the distance between rows and between columns. Adding a plus sign (+) or a minus sign (-) determines direction.

Click the Pick Both Offsets button to use the pointing device to specify the diagonal corners of a cell in the array. The cell determines the vertical and horizontal spacing of the rows and columns.

Click the Pick Row Offset or Pick Column Offset button to use the pointing device to specify the horizontal and vertical spacing.

The example box displays the result.

To change the rotation angle of the array, enter the new angle next to Angle of Array.

The default angle 0 direction setting can also be changed in UNITS.

Click OK to create the array.

Toolbar: Modify

Command entry: ARRAY

b- To create a polar array

Click Home tab Modify panel Array.At the command prompt, enter array.

In the Array dialog box, select Polar Array.

Next to Center Point, do one of the following: Enter an X value and a Y value for the center point of the polar array. Click the Pick Center Point button. The Array dialog box closes and you are prompted for object

selection. Use the pointing device to specify the center point of the polar array.

Click Select Objects.

The Array dialog box closes and you are prompted for object selection.

Select the objects to be arrayed.

In the Method box, select one of the following methods: Total Number of Items & Angle to Fill Total Number of Items & Angle Between Items Angle to Fill & Angle Between Items

Enter the number of items (including the original object), if available.

Use one of the following methods: Enter the angle to fill and angle between items, if available. Angle to Fill specifies the distance to

fill around the circumference of the array. Angle Between Items specifies the distance between each item.

Click the Pick Angle to Fill button and the Pick Angle Between Items button. Use the pointing device to specify the angle to fill and the angle between items.

The example box displays the result.

You can set any of the following options: To rotate the objects as they are arrayed, select Rotate Items As Copied. The example area

displays the result. To specify the X,Y base point, select More, clear the Set to Object's Default option and enter

values in the X and Y boxes, or click the Pick Base Point button and use the pointing device to specify the point.

Click OK to create the array.

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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6-MOVE :Moves objects a specified distance in a specified direction

To move an object using two points

Click Home tab Modify panel Move.

Select the objects to move.

Specify a base point for the move.

Specify a second point.

The objects you selected are moved to a new location determined by the distance and direction between the first and second points.

Toolbar: Modify

Command entry: MOVE 7-ROTATE Rotates objects around a base point

To rotate an object

Click Home tab Modify panel Rotate.

Select the object to rotate.

Specify the base point for the rotation.

Do one of the following: Enter the angle of rotation. Drag the object around its base point and specify a point location to which you want to rotate the

object. Enter c to create a copy of the selected objects. Enter r to rotate the selected objects from a specified reference angle to an absolute angle.

Toolbar: Modify

Command entry: ROTATE 8-SCALE :Enlarges or reduces selected objects, keeping the proportions of the object the same after scaling.

To scale an object by a scale factor

Click Home tab Modify panel Scale.

Select the object to scale.

Specify the base point.

Enter the scale factor or drag and click to specify a new scale.

Toolbar: Modify

Command entry: SCALE

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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9-STRETCH :Stretches objects crossed by a selection window or polygon

To stretch an object

Click Home tab Modify panel Stretch.

Select the object using a crossing window selection.

The crossing window must include at least one vertex or endpoint.

Do one of the following: Enter the displacement in the form of a relative Cartesian, polar, cylindrical, or spherical

coordinate. Do not include the @ sign, because a relative coordinate is assumed. Press ENTER at the prompt for the second point of displacement.

Specify the base point for the stretch, and then specify a second point, to determine the distance and direction.

Any objects with at least one vertex or endpoint included within the crossing window are stretched. Any objects that are completely within the crossing window, or selected individually, are moved without stretching.

Toolbar: Modify

Command entry: STRETCH 10-TRIM : Trims objects to meet the edges of other objects

To trim an object

Click Home tab Modify panel Trim.

Select the objects to serve as cutting edges. To select all displayed objects as potential cutting edges, press ENTER without selecting any objects.

Select the objects to trim.

Toolbar: Modify

Command entry: TRIM 11-EXTEND : Extends objects to meet the edges of other objects

To extend an object

Click Home tab Modify panel Extend.

Select the objects to serve as boundary edges. To select all displayed objects as potential boundary edges, press ENTER without selecting any objects.

Select the objects to extend.

Toolbar: Modify

Command entry: EXTEND 12-BREAK : Breaks the selected object at a single point.

To break an object at a single point

Click Home tab Modify panel Break.

Select the object to break. By default, the point at which you select the object is the first break point. To select a different pair of break points, enter f (First) and specify the first break point.

Specify the second break point. To break an object without creating a gap, enter @0,0 to specify the previous point.

Toolbar: Modify

Command entry: BREAK

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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13- JOIN : Joins similar objects to form a single, unbroken object

To join objects

Click Home tab Modify panel Join.

Select the source object to which you want to join objects.

Select one or more objects to join to the source object. Valid objects include arcs, elliptical arcs, lines, polylines, and splines. Additional restrictions for each type of objects are described in the JOIN command.

Toolbar: Modify

Command entry: JOIN 14- CHAMFER : Bevels the edges of objects

To chamfer an entire polyline

Click Home tab Modify panel Chamfer.

Enter p (Polyline).

Select the polyline. The polyline is chamfered using the current chamfer method and the default distances.

Toolbar: Modify

Command entry: CHAMFER 15- FILLET : Rounds and fillets the edges of objects

To fillet an entire polyline

Click Home tab Modify panelFillet.

Enter p (Polyline).

Select the polyline.

Toolbar: Modify

Command entry: FILLET 16- EXPLODE : Breaks a compound object into its component objects

To explode a block reference

Click Home tab Modify panel Explode. At the command prompt, enter explode.

Select the block to explode and press ENTER. The block reference is disassembled into its component objects; however, the block definition still exists in the drawing for insertion later.

Toolbar: Modify

Command entry: EXPLODE

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Chapter 4

Overview of Layers

Layers are used to group information in a drawing by function and to enforce linetype, color, and other standards.

Layers are the equivalent of the overlays used in paper-based drafting. Layers are the primary organizational tool used in drawing. You use layers to group information by function and to enforce linetype, color, and other standards.

LAYER : Manages layers and layer properties.

Use layers to control the visibility of objects and to assign properties such as color and linetype. Objects on a layer normally assume the properties of that layer. However, you can override any layer property of an object. For example, if an object’s color property is set to BYLAYER, the object displays the color of that layer. If the object’s color is set to Red, the object displays as red, regardless of the color assigned to that layer. The layer property manager is where all the layers are controlled. The layout above shows a typical use of layers.

From the layer property manager we can:

Add a New Layer - Press the New button to create a new layer.

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Delete a Layer - Press the delete button to delete the selected layer. Set Current layer - Press the current button to set the selected layer current. All objects drawn will then be drawn on this current layer. Show Details - Press the show details button to see more detailed information about the selected layer. Each layer also has the following options against it:

Name - Displays the layer name. On - Controls if the layer is on or off. Select the light bulb to turn the layer off on the drawing. Freeze in all VP - Pressing this will freeze the layer in all viewports as well as the current model view (see lesson 10 to learn about viewports) Lock - This handy feature locks a layer preventing any content of the layer from being modified. Colour - Change this to whichever colour you like. All objects drawn on the layer will display the chosen colour provided that the objects colour setting in the object properties toolbar (shown above) is set to 'By Layer'. Line type - Set the default linetype for all objects drawn on the layer. i.e continuous, dashed, dotted etc.

Line weight - Set the thickness a line appears .Default is no thickness. This option can be toggled on/off on the display by the LWT button above the command console. Plot - Select if the layer will be shown when the drawing is plotted (printed).

The current layer, layer colour, linetype and lineweight can all be controlled outside of the layer properties manager via the object properties toolbar. That's it for basic layer controls! Get used to using layers as you will be using them often - especially when you find you need to start managing large drawing files that contain a lot of information.

To create a new layer

Click Home tab Layers panel Layer Properties.

In the Layer Properties Manager, click the New Layer button. A layer name, such as LAYER1, is automatically added to the layer list.

Enter a new layer name by typing over the highlighted layer name.

To change the properties, click icons. When you click Color, Linetype, Lineweight, or Plot Style, a dialog box is displayed.

(Optional) Click in the Description column and enter text.

Click Apply to save your changes, or click OK to save and close.

Toolbar: Layer Properties

Command entry: LAYER

Change Layer Settings and Layer Properties

To change the layer of one or more objects

Select the objects whose layer you want to change.

On the Layers toolbar, click the Layer control.

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By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Select the layer that you want to assign to the objects.

Press ESC to remove selection.

Toolbar: Layers

CLASSICLAYER : Opens the modal Layer Properties Manager

COPYTOLAYER : Copies one or more objects to another layer

LAYCUR : Changes the layer of selected objects to the current layer

LAYDEL: Deletes all objects on a layer and purges the layer

LAYER : Manages layers and layer properties

LAYFRZ : Freezes the layer of selected objects

LAYISO : Hides or locks all layers except those of the selected objects

LAYMCH: Changes the layer of a selected object to match the destination layer

LAYMRG : Merges selected layers into a target layer, removing the previous layers from the drawing

LAYOFF : Turns off the layer of a selected object

LAYON : Turns on all layers in the drawing

LAYTHW : Thaws all layers in the drawing

LAYUNISO : Restores all layers that were hidden or locked with the LAYISO command

LAYWALK : Displays objects on selected layers and hides objects on all other layers

AutoCAD zoom and pan ZOOM : Increases or decreases the apparent size of objects in the current viewport

PAN Moves the view in the current viewport

Various zoom commands available, and their uses.

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Overview of Dimensioning Dimensioning is the process of adding measurement annotation to a drawing. You can create dimensions for a variety of object types in many orientations. The basic types of dimensioning are

Linear

Radial (radius, diameter and jogged)

Angular

Ordinate

Arc Length Linear dimensions can be horizontal, vertical, aligned, rotated, baseline, or continued (chained). Some examples are shown in the illustration.

DIMANGULAR : Creates an angular dimension

DIMARC: Creates an arc length dimension

DIMBREAK :Breaks or restores dimension and extension lines where they cross other objects

DIMDIAMETER :Creates a diameter dimension for a circle or an arc

DIMEDIT :Edits dimension text and extension lines

DIMINSPECT :Adds or removes inspection information for a selected dimension

DIMJOGGED :Creates jogged dimensions for circles and arcs

DIMJOGLINE :Adds or removes a jog line on a linear or aligned dimension

DIMLINEAR :Creates a linear dimension

DIMORDINATE :Creates ordinate dimensions

DIMRADIUS :Creates a radius dimension for a circle or an arc

DIMREASSOCIATE :Associates selected dimensions to geometric objects

DIMSPACE :Adjusts the spacing between linear dimensions or angular dimensions

DIMSTYLE :Creates and modifies dimension styles

DIMTEDIT :Moves and rotates dimension text and relocates the dimension line

PROPERTIES :Controls properties of existing objects

QDIM :Quickly creates a series of dimensions from selected objects

Overview of Dimension Styles

A dimension style is a named collection of dimension settings that controls the appearance of dimensions, such as arrowhead style, text location, and lateral tolerances. You create dimension styles to specify the format of dimensions quickly, and to ensure that dimensions conform to industry or project standards.

When you create a dimension, it uses the settings of the current dimension style

If you change a setting in a dimension style, all dimensions in a drawing that use the style update automatically

You can create dimension substyles that, for specified types of dimensions, deviate from the current dimension style

If necessary, you can override a dimension style temporarily

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By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Linear Dimensions Linear dimensions can be horizontal, vertical, or aligned. With aligned dimensions, the dimension line is parallel to the line (imaginary or real) between the extension line origins. Baseline (or parallel) and continued (or chain) dimensions are series of consecutive dimensions that are based on a linear dimension.

Aligned Dimensions can create dimensions that are parallel to the locations or objects that you specify

Radial Dimensions

Radial dimensions measure the radii and iameters of arcs and circles with optional centerlines or a center mark.

To create a radius dimension

At the command prompt, enter dimradius.

Select an arc, circle, or polyline arc segment.

Enter options as needed: To edit the dimension text content, enter t (Text) or m (multiline text). Editing within or

overwriting the brackets (<>) changes or removes the dimension value. Adding text before or after the brackets appends text before or after the dimension value.

To edit the dimension text angle, enter a (Angle).

Specify the leader line location.

Toolbar: Dimension

Command entry: DIMRADIUS

Overview of Text Styles All text in a drawing has a text style associated with it. When you enter text, the program uses the current text style, which sets the font, size, obliquing angle, orientation, and other text characteristics. If you want to create text using a different text style, you can make another text style current.

STYLE

Creates, modifies, or specifies text styles

To set the current text style

On the Styles toolbar, in the Text Style control, click the arrow and select a text style from the list.

Command entry: STYLE

To set text height in a text style

Click Home tab Annotation panel Text Style.

In the Text Style dialog box, select a style from the Style Name list.

Under Font, enter the text height (in drawing units) in the Height box.

To update existing text that uses this text style, click Apply.

Click Close.

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Toolbar: Styles

Command entry: STYLE

To set the obliquing angle in a text style

Click Home tab Annotation panel Text Style.

In the Text Style dialog box, select a text style from the Style Name list.

Under Effects, enter an angle between -85 and 85 in the Oblique Angle box.

A positive value slants text to the right. A negative value slants text to the left.

To update existing text that uses this text style, click Apply.

Click Close.

Use Precision Tools

1-Use Coordinates and Coordinate Systems (UCS)

For precise coordinate input, you can use several coordinate system entry methods. You can also use a movable coordinate system, the user coordinate system (UCS), for convenient coordinate entry and to establish workplanes.

To enter absolute Cartesian coordinates (2D)

At a prompt for a point, enter coordinates in the tooltip using the following format: # x,y If Dynamic Input is turned off, enter coordinates on the command line using the following format: x,y

2-Use Dynamic Input

Dynamic Input provides a command interface near the cursor to help you keep your focus in the drafting area.

To turn on or turn off Dynamic Input

On the status bar, click the dynamic input button, or press F12.

To turn off Dynamic Input temporarily, hold down the F12 key while you work.

NoteThe F12 temporary override key does not turn on Dynamic Input.

3-Snap to Locations on Objects (Object Snaps) Instead of entering coordinates, you can specify

points relative to existing objects such as endpoints of lines or center points of circles.

Use Object Snaps

Use object snaps to specify precise locations on objects. For example, you can use an object snap to draw a line to the center of a circle or to the midpoint of a polyline segment.

To turn on and turn off running object snaps as you work

On the status bar, click Osnap , or press F3.

If running object snaps have been set, the settings are turned on or off.

To turn running object snaps on and off temporarily, hold down the F3 key while you work.

Command entry: OSNAP

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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4- Restrict Cursor Movement

Several tools are available that you can use to restrict or lock the movement of your cursor.

Grid and Grid Snap Displays a grid pattern in the current viewport

To display a grid and set grid spacing

Click Tools menu Drafting Settings.

In the Drafting Settings dialog box, Snap and Grid tab, select Grid On to display the grid.

Under Snap Type, make sure Grid Snap and Rectangular Snap are selected.

For Grid X Spacing, enter the horizontal grid spacing in units.

To use the same value for vertical grid spacing, press ENTER. Otherwise, enter a new value for Grid Y Spacing.

Click OK.

Command entry: DSETTINGS

Shortcut menu: On the status bar, right-click the snap button . Click Settings.

Orthogonal Locking (Ortho Mode) Constrains cursor movement to the horizontal or vertical direction

To turn on or turn off Ortho mode

On the status bar, click the Ortho button . To turn Ortho on or off temporarily, hold down the SHIFT key while you work. While you use the temporary override key, the direct distance entry method is not available. NoteTurning on Ortho automatically turns off polar tracking.

Command entry: ORTHO

Polar Tracking and Polar Snap Polar tracking restricts cursor movement to specified angles. PolarSnap restricts cursor movement to specified increments along a polar angle.

To turn on and turn off polar tracking

Press F10, or click the polar button on the status bar. To turn polar tracking on or off temporarily, hold down the F10 key while you work.

Combine or Offset Points and Coordinates

To specify a new point location, you can combine coordinate values from several points or you can specify offsets from existing objects.

Specify Distances

When specifying a point, you can enter distances, offsets, and measured intervals.

Extract Geometric Information from Objects

The inquiry and calculation commands can provide information about objects in your drawing and do useful calculations.

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Isometric Grid and Snap mode The Isometric Snap/Grid mode helps you create 2D isometric images that represent 3D objects. The Isometric Snap/Grid mode helps you create 2D images that represent 3D objects. By setting the Isometric Snap/Grid, you can easily align objects along one of three isometric planes; however, although the isometric drawing appears to be 3D, it is actually a 2D representation. Therefore, you cannot expect to extract 3D distances and areas, display objects from different viewpoints, or remove hidden lines automatically.

ISOPLANE

Specifies the current isometric plane

To turn on an isometric plane

Click Tools menu Drafting Settings. In the Drafting Settings dialog box, Snap and Grid tab, under Snap Type, select Isometric Snap.

Click OK. Alternative

You can cycle through the three isometric planes by pressing F5.

Command entry: DSETTINGS

To change to a different isometric plane quickly

Press F5 or CTRL+E to select a different isometric plane. The program cycles through the Isoplane Top, Isoplane Right, and Isoplane Left settings.

To draw an isometric circle

Click Tools menu Drafting Settings. In the Drafting Settings dialog box, Snap and Grid tab, select Isometric Snap. Click OK. Click Draw Ellipse Axis, End. Enter i (Isocircle). Specify the center of the circle. Specify the radius or diameter of the circle.

Toolbar: Draw

Command entry: ELLIPSE

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Part II

Exercise 01

Redraw the following using basic AutoCAD commands.

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Exercise 02

Redraw the following orthographic views using basic AutoCAD Commands

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Exercise 03

Draw the orthographic views of the following figures .

Fig.1

Fig.3 Fig.4

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Exercise 04

Redraw the following figures using Isometric Snap mode

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Sample 1

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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Sample 2

AutoCAD Practical Manual

By Prof.Shaikh Ibrahim Ismail Automobile Engg. Dept., MHSSCE

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AutoCAD Common Shortcut Key (2D)

Draw Commands Modify Commands

L LINE XL CONSTURCTION LINE PL POLYLINE POL POLYGON REC RECTANGLE A ARC C CIRCLE REVCLOUD REVCLOUD SPL SPLINE EL ELLIPSE I INSERT BLOCK B DEFINE BLOCK W WRITE BLOCK H HATCHING DT TEXT (SINGLE LINE) T MTEXT (MULTILINE)

E ERASE CO COPY MI MIRROR O OFFSET AR ARRAY M MOVE RO ROTATE SC SCALE S STRETCH TR TRIM EX EXTEND BR BREAK, BREAK AT POINT J JOIN CHA CHAMFER F FILLET X EXPLODE

3

Other Useful Command

PE POLY EDIT OP OPTION DI DIST AREA AREA MASSPROP MASSPROP LTSCALE LINETYPESCALE PSLTSCALE PAPER SPACE LT SCALE LA LAYER LI LIST Z ZOOM P PAN MA MATCH PROPERTIES

Function

Keys

F1 Displays Help

F2 Toggles Text Window

F3 Toggles OSNAP

F4 Toggles TABMODE

F5 Toggles ISOPLANE

F6 Toggles UCSDETECT

F7 Toggles GRIDMODE

F8 Toggles ORTHOMODE

F9 Toggles SNAPMODE

F10 Toggles Polar Tracking

F11 Toggles Object Snap Tracking

F12 Toggles Dynamic Input