Computer Aided Drafting Practical File

CH. DEVI LAL MEMORIAL GOVERNMENT ENGG. COLLEGEPANIWALA MOTA, SIRSA

LABORATORY MANUALEXPERIMENT NO.:ME-CAD-EX-01-10 ISSUE NO.: ISSUE DATE:

REV. NO.: 01 REV. DATE: - PAGE: 01/02DEPTT. : MECHANICAL ENGINEERING LABORATORY: CAD (ME-211 E) SEMESTER: 3rd

LIST OF EXPERIMENTS AS PER CURRICULUMS.

No.EXPERIMENTS EXP. No. PAGE No.

1

Setting up of drawing environment by setting drawing limits, drawing units, naming the drawing, naming layers, setting line types for different layers using various type of lines in engineering drawing, saving the file with .dwg extension.

ME-CAD-EX-01

2Layout drawing of a building using different layer and line colors indicating all Building details. Name the details using text commands, Make a title Block.

ME-CAD-EX-02

3To Draw Orthographic projection Drawings (Front, Top and side) of boiler safety valve giving name the various components of the valve.

ME-CAD-EX-03

4Make an Isometric dimensioned drawing of a connecting Rod using isometric grid and snap.

ME-CAD-EX-04

5 Draw quarter sectional isometric view of a cotter joint. ME-CAD-EX-05

6

Draw different types of bolts and nuts with internal and external threading in Acme and square threading standards. Save the bolts and nuts as blocks suitable for insertion.

ME-CAD-EX-06

7Draw 3D models by extruding simple 2D objects, dimension and name the objects.

ME-CAD-EX-07

8 Draw a spiral by extruding a circle. ME-CAD-EX-08

LIST OF EXPERIMENTS BEYOND CURRICULUM9 To draw the front view – half in section and side view

of the Knuckle Joint.ME-CAD-EX-09

10 To create a 3D model of hexagonal nut and bolt ME-CAD-EX-10

1 | P a g e

Following exercises will be carried out using educational software’s (AutoCad-2006, I DEAS, Pro-Engineer etc)

INDEX

Sr. No. EXPERIMENTS EXP. No.PAGE

No.Sign

1

Setting up of drawing environment by setting drawing limits, drawing units, naming the drawing, naming layers, setting line types for different layers using various type of lines in engineering drawing, saving the file with .dwg extension.

ME-CAD-EX-01

2

Layout drawing of a building using different layer and line colors indicating all Building details. Name the details using text commands, Make a title Block.

ME-CAD-EX-02

3

To Draw Orthographic projection Drawings (Front, Top and side) of boiler safety valve giving name the various components of the valve.

ME-CAD-EX-03

4Make an Isometric dimensioned drawing of a connecting Rod using isometric grid and snap.

ME-CAD-EX-04

5Draw quarter sectional isometric view of a cotter joint.

ME-CAD-EX-05

6

Draw different types of bolts and nuts with internal and external threading in Acme and square threading standards. Save the bolts and nuts as blocks suitable for insertion.

ME-CAD-EX-06

7Make a 3-D model of hexagonal bolt with V-type thread. ME-CAD-EX-07

8Draw 3D models by extruding simple 2D objects, dimension and name the objects.

ME-CAD-EX-08

2 | P a g e

EXPERIMENT No. – 1EXPERIMENT No. – 1

AIM: Setting up of drawing environment by setting drawing limits, drawing units, naming the drawing, naming layers, setting line types for different layers using various type of lines in engineering drawing, saving the file with .dwg extension.

Software used: AutoCAD 2006.

1.1 To open a drawing 1. Click File menu Open. 2. In the Select File dialog box, select one or more files. Click Open.

The icons on the left side of the dialog box provide quick access to commonly used files and file locations. To reorder the icons, drag them to a new location. To add, modify, or remove an icon, right-click the icon to display a shortcut menu.

Command: OPEN

Fig. 1.1 Dialog box for open a file.1.2 Drawing limits:-

The drawing limits are two dimensional points in the world coordinate system that represent a lower left-limit and an upper-right limits. You cannot impose limits on the Z direction. Drawing limits also determine the area of the drawing that can display grid dots. When plotting a drawing, you can also specify the drawing limits as the area to plot.

Drawing Limits command is used to specify the drawing sheet size and the following procedure is adopted to set the limits of a drawing.

3 | P a g e

Command: limits

Reset model space limits: Specify lower left corner or [ON/OFF] <0.0000, 0.0000>: use one of the point fixing

methods Specify upper right corner <420.0000, 297.0000>: use one of the point fixing methods

Figure 1.2 shows the step by step procedure for limits command in the command prompt window.

Fig. 1.2 Command prompt with limits.

1.3 Drawing units:-

Every object you create is measured in drawing units. Before you start to draw, you must decide what one drawing unit will represent based on what you plan to draw. Then you create your drawing at actual size with that convention. For example, a distance of one drawing unit typically represents one millimeter, one centimeter, one inch, or one foot in real-world units

AutoCad 2006 displays the Drawing Units dialog box.

4 | P a g e

Fig. 1.3 Unit format and precision

To set the units format and precision

1.Click Format menu Units.

2.In the Drawing Units dialog box, under Length, select a unit format and precision.

3.Click OK

Icon/Button DescriptionSets the current format for the unit of measure. The values include Architectural, Decimal, Fractional and Scientific. The Architectural and Engineering formats produce feet and inches displays and assume that each drawing unit represent one inch. The other formats can represent any real-world unit. Precision sets the number of decimal places for the current unit format.

Specifies the current angle format and the precision for the current angle. Type sets the current angle format. Precision sets the precision for the current angle format.

Clockwise calculates positive angles in the clockwise direction. The default direction for positive angles is counter clockwise.

5 | P a g e

Control the unit of measurement for blocks that are dragged into the current drawing using a tool palette, DesignCenter. 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.

1.4 Naming the drawing:-

We can give the name of drawing. You can select one of the template files supplied, or create your own template files. You can create a new drawing with Metric or Imperial setting by clicking the option button in the right corner of the select template dialog box.

Create and Name the layers:-

Layer is an organizing tool. Layers are like one, where you can keep various types of information. It’s always a good idea to keep notes and reference symbols about each element of the drawing as well as drawing dimensions on a new layer. After you choose new layer the list displays a layer named LAYER1. You can edit this layer immediately. To create multiple layers more quickly, you can select a layer name for editing and enter multiple layer names separated by commas.

Fig.1.4 Layer Properties Manager.

1.5 Setting linetype:-

Linetypes greatly improve the readability of technical drawings. You can make important features stand out with bold line weights. Invoking this command in AutoCAD, displays the Linetype manager dialog box.

6 | P a g e

Fig. 1.5 Linetype manager

1.6 Saving the file with drawing extension:-

You save drawing files for later use just as you do with other Microsoft Windows applications. You can also set up automatic saving and backup files and save only selected objects.

The file extension for drawing files is .dwg, and unless you change the default file format in which drawings are saved, drawings are saved in the latest drawing-file format. This format is optimized for file compression and for use on a network.

To save a drawing

1. Click File menu Save.

If you previously saved and named the drawing, any changes made are saved and the Command prompt is redisplayed. If you have never saved the drawing, the Save Drawing As dialog box is displayed.

7 | P a g e

Fig. 1.6 Save Drawing As.

2. In the Save Drawing As dialog box under File Name, enter the new drawing name; the file extension is not required. Click Save.

We can also save the file with the drawing extension either in our documents with our name.

8 | P a g e

EXPERIMENT No. - 2EXPERIMENT No. - 2

AIM: Layout drawing of a building using different layer and line colors indicating all Building details. Name the details using text commands, Make a title Block.

Software used: AutoCAD 2006

Command used: - line, circle, trim, offset, micro- image, layers, line color.

Layers are different lines of different colors which are placed on the drawing sheet or screen to form a drawing shape or buildings layout.

First select different layers accordingly layout of buildings.

Now draw different layers accordingly layout of buildings.

Now change the color of layer in the layout

In the different layer we can on /off the different layer and lock unlocks different layers.

9 | P a g e

10 | P a g e

11 | P a g e


AIM: To Draw Orthographic projection Drawings (Front, Top and side) of boiler safety valve giving name the various components of the valve.

12 | P a g e

13 | P a g e

Software usedAutoCAD 2006 has been used to make a drawing.

Command used The numerous Draw and Modify commands have been used to draw the orthographic views (Front, Side and Top view) of the spring loaded safety valve.

The detail of commands is given below:

Draw commands

Line Circle Rectangle Construction line Arc Spline Ray

Modify commands

Erase Copy Mirror Array Move Rotate Trim

14 | P a g e


AIM: Make an orthographic (front, side, top) dimensioned drawing of a connecting Rod.

Drawing: Orthographic dimensioned drawing of connecting rod is given below,

15 | P a g e

Fig. 4.1 Connecting Rod


16 | P a g e

Command used: Line, Arc, Circle, Mirror

Fig. 4.2 Connecting Rod(with AutoCad)

17 | P a g e


AIM: Draw quarter sectional isometric view of a cotter joint.


Drawing: Isometric dimensioned drawing is taken from text book of Machine Drawing and given

below,

18 | P a g e

Fig. 5.1 Quarter sectional isometric view of a Spigot and Socket cottered joint

Command used: Line, Arc (Start-centre-end), Trim, Hatch, Copy, Move, Erase

Figure 5.2 (a,b) shows the Quarter sectional isometric view of a Spigot and Socket cottered joint which have been made with the help of AutoCAD 2006

19 | P a g e

(a)

(b)

Fig. 5.2 (a,b) Quarter sectional isometric view of a Spigot and Socket cottered joint.

20 | P a g e


AIM: Draw different types of bolts and nuts with internal and external threading in Acme and square

threading standards. Save the bolts and nuts as blocks suitable for insertion.

Software used: AutoCAD 2006

Drawings: Drawings of different type of bolt, thread and nut are given below,

1. HEXAGONAL BOLT

A hexagonal bolt with head, length with and without threading and end is shown in Figure 6.1. The

threaded portion is drawn as per rule. Note that the chamfer angle is 45.

Fig. 6.1 HEXAGONAL BOLT

21 | P a g e

2. Square and Cheese head boltSquare and cheese head bolt without threading is shown in fig. 6.2 (a) and (b).

(a)- Square head bolt (b) - Cheese head bolt

3. Acme and Buttress ThreadAcme thread and Buttress threads as shown in Figures 6.3(a) and (b) are other variations.

22 | P a g e

(a) Acme Thread Profile

(b)Buttress Thread

Fig. 6.3 (a,b) Acme and Buttress Thread

4. Nut: Figure 6.4 represent the various types of nut.

23 | P a g e

(a) (b) (c)

(d) (e) (F)

Fig. 6.4 Various types of nut

Prepared drawing of various types of bolt and nut in AutoCAD is given below.

24 | P a g e

25 | P a g e

26 | P a g e


AIM: Make a 3-D model of hexagonal bolt with V-type thread.

Software used: Pro/E Wildfire 4.0

Command used: Line, Trim, Extrude, Helical Sweep (cut)

Drawings: Drawings of hexagonal bolt is given below,

1. HEXAGONAL BOLT

A hexagonal bolt with head, length with and without threading and end is shown in Figure 7.1.

The threaded portion is drawn as per rule. Note that the chamfer angle is 45.

Fig. 7.1 HEXAGONAL BOLT

27 | P a g e

Procedure:

1. Draw a hexagon with line command using sketch module of software.

2. Add material to sketched section by extrude command using part module of the software.

3. To create v-type thread, apply helical sweep (cut) and set pitch of the thread.

Fig. 7.2 Hexagonal bolt with v-type thread

28 | P a g e


Aim: Draw 3D models by extruding simple 2D objects, dimension and name the objects.

Software Used: AutoCAD 2006

Command Used: Extrude.

Isometric dimensioned Drawing of models

29 | P a g e

Procedure:

1. Draw a suitable two dimensional geometry.2. Apply REGION to convert it into a single entity.3. Third step is to add material using extrude command.

30 | P a g e

3D Models

31 | P a g e

Education

Computer Aided Drafting Practical File