BTech Lab Manual Autocad

Career Point University

Laboratory Instruction Manuals

MEL – Auto CAD

LTP:0-0-2

DEPARTMENT OF MECHANICAL ENGINEERING

B.TECH 3rd Year/ 5th Semester

Campus: Alaniya, Kota- 325003 (Raj.) 0744-2832094, 2832092 1

AUTOCAD

To compete and win in today’s design marketplace, engineers need to create and revise

mechanical drawings faster than ever before. AutoCAD Mechanical software offers

significant productivity gains over standard AutoCAD software by simplifying complex

mechanical design work .

What’s New in 2012AutoCAD 2012 introduces new features along with continued enhancements to existing

capabilities. You will notice the following differences in Applying AutoCAD 2012:

Further refi nements to the user interface. The arrangement of tabs, panels, and

buttons on the Ribbon has improved, allowing for faster, more intuitive modeling–

particularly in the 3D Modeling workspace.

An entirely new 3D object, the 3D mesh, which allows users to create models

with smooth, flowing geometry in 3D space. When mesh modeling is combined

with surface modeling and solid modeling, AutoCAD users now have more power

and freedom to design in three dimensions than ever before.

New tools for working with solid primitives and mesh primitives. Sub object filters

and gizmo tools make it much easier to select and modify any face, edge, or

vertex of a

primitive.

Dynamic blocks are easier to author and edit, with new procedures and on-screen

icons.


S.No.

List of experiments

1. Introduction to AutoCAD

2. Basic Facilities In AutoCAD

3. Basic Commands of AutoCAD : 2D

4. Basic Commands of AutoCAD : 3D

5. Creation of Simple Objects

6. Creation of Special Curves

7. Projection and Section of Simple Solids

8. Orthographic Views of Solids

9. Isometric Views of Objects

10. 3D Modeling of Simple Objects

11. 2D Multiple Views from 3D Models

12. Expt 1 : To develop the given model by using auto cad 2D commands and to specify its Dimension.

13. Expt 2 : To develop the given model by using auto cad 2D commands and to specify itsDimension.

14. Expt 3: To draw the isometric drawings by using AutoCAD 2012 2D commands and theDimensions can be determined by counting the no of grids.

15. Expt 4 : To draw the isometric drawing by using AutoCAD 2D drawing commands.

16. Expt 5 : To develop the given model by using auto cad 2D commands and to specify its Dimension.


LEARNING OBJECTIVES

Basic understanding of AutoCAD , its commands and its application in 2D and 3d modeling

REFERENCE BOOKS:

1 AutoCAD by Ibrahim Zaheid

2 Mastering AutoCAD 2013 and AutoCAD LT 2013 by George Omura and Brian C. Benton

3 Mastering AutoCAD 2012 and AutoCAD LT 2012 (Autodesk Official Training

Guides) by George Omura and Rick Graham


http://www.amazon.com/Mastering-AutoCAD-Autodesk-Official-Training/dp/0470952881/ref=sr_1_9?s=books&ie=UTF8&qid=1360141223&sr=1-9&tag=natava-20

http://www.amazon.com/Mastering-AutoCAD-2013-LT/dp/1118174070/ref=sr_1_2?s=books&ie=UTF8&qid=1360141223&sr=1-2&tag=natava-20

INTRODUCTION

COMPUTER:

It is an ultra fast electronic counting machine that can transmit & manipulate information.

The essential components of a computer are:

i) Processor which is the brain of the computer.ii) Memory unit which stores data & instructions.iii) Disc storage unit which enables permanent storage of data.iv) Input/Output which enables permanent storage of data.v) Programs which contain instruction to the hardware.

A computer essentially consists of hardware & software.

HARDWARE:

The physical devices consisting of mechanical parts that make up the computer are called hardware. It includes physical components such as keyboard, monitor, electronic circuits, disc drives etc.

PROGRAM:

Program refers to a set of instructions to a computer to perform a task. The program may be as simple as written to add 2 numbers & as complex as for weather forecasting.

SOFTWARE:

A collection of program forms software. Without software, hardware cannot work.

TYPES OF SOFTWARE:

It is mainly classified into two categorie

1. SYSTEM SOFTWARE:

It is a collection of programs needed to operate & control the functioning of a computer. These are the software which provides the environment for writing & running the application programs. These software include

a) Opening system which acts as an interface between the user & computer hardware.b) The service programs like compilers & interpreters which are used to develop

application programs.


EXAMPLES:

MS DOS C compiler Basic interpreter

2. APPLICATION SOFTWARE:

These are the software which enables us to carry out specific tasks on the computer.

This type of software consists of a set of programs to carry out operations for specific tasks on the computer and specific application programs.

E.g.: a) AutoCAD

b) Computerized billing system, inventory, package etc..

c) Tally

CAD SYSTEM:

The process of model creation, analysis & evaluation of an engineering design through the use of computers is known as Computer Aided Design. CAD system consists of computer hardware & associated software.

While the software parts consist of implemental aspects of the design methodologies, the hardware resources assist in executing of this software. The hardware includes the computer graphics terminals & the peripheral devices. The software parts consist of the computer graphics for the user interaction of the application program for design. In a CAD system the user enters the necessary information about a part like geometrical details through interactive computer graphics with the help of input devices like mouse or keyboard. ICG is a user friendly environment having a graphical user interface which facilitates user interaction with the CAD system. These inputs are used by the application program to continue with further processing like creating model, assigning constraints & carrying out analysis. Model can be created by involving entity creation modification commands. The results of design analysis can be obtained by making use of the output devices like printers, plotters, etc.

HARDWARE IN CAD:

CAD hardware is required for the following purposes as listed.

1. Input of information regarding model2. Output of engg.dwg. of the model created.3. Processing of the input information about a model for its design details.


CAD system should be powerful enough in terms of computing power & graphics capabilities. The input devices can be keyboard, mouse, digitizer, etc. A graphics terminal should support graphical user interface provided by the CAD software. The output devices can be printer or plotter. The secondary storage media assists in taking the back ups of the CAD information on storage devices like floppy discs, CDs, DVDs, Pen Drives, Portable HD. The CPU is the main controlling part of the entire CAD system. The processor should be fast enough to handle huge amount of information & carry out complex mathematical equations.

OPERATOR INPUT DEVICES:

Interactive computer graphics requires user to input information through different means into the graphics package. At the same time user should be able to modify graphics entities even of small details. The user should also be able to draw the images interactively & in real time. In a design work station, a number of input devices are available. All these devices can be grouped into three categories.

1) Cursor control device2) Digitizer3) Keyboard terminal

CURSOR CONTROL DEVICES:

These devices control the position of a bright spot on the graphic screen. The movement of this bright spot is sensed by the CAD system & the graphic image can be created by clicking on information about the co-ordinates location.

The various cursor control devices are as follows:

MOUSE:

It is the most popular input device. A mechanical mouse consists of wheels placed orthogonally at the bottom of the mouse. These wheels get actuated for movements of the mouse along x & y axes. The values are recorded by pressing the mouse buttons. In optical mouse system the light source is provided on the button with an optical encoder.

DIGITIZER:

Digitizer boards or tablets are electro-mechanical vector graphic input devices that resemble a drafting board. These are used together with a movable stylus called puck. The puck can be moved over the surface to following existing lines. It is a common technique in CAD systems for taking x and y co-ordinates from a paper drawing. The tracking device (puck) contains a switch for the user to record the desired x and y co-ordinates. The co-ordinates are either directly sent to the computer or stored in secondary storage devices like magnetic tapes. Digitizers with a large board provide high resolution and accuracy. Digitizers are more frequently used to create drawings using


an interactive drafting package to enter a sketch or a drawing which can be redrawn or edited as the display appears on the CRT screen.

KEYBOARD TERMINALS:

It is an alphanumeric terminal used to enter commands, co-ordinates, functions and process data to the CAD system. The information typed is displayed on the CRT screen. The typed information displayed on the CRT screen can be changed. CAD systems make use of special function keyboards. These function keys are provided to eliminate extensive typing of commands. The number of function keys varies from about 8 to 80.

AutoCAD:

AutoCAD is a highly professional computer aided design & drafting package which can run on low cost microcomputers. AutoCAD brings the benefits of sophisticated technology which was previously available to large & costly system, within the reach of desktop.

For a computer user, AutoCAD is easy to learn and one need not possess any previous computer experience & knowledge to get started in Auto CAD. The set of menu are user friendly & easy to follow. Drawings of any size can be created & revised. The drawing can be stored on floppy, hard disc, CDs, DVDs or pen drives and can be plotted to any scale.

There is virtually no limit to the kind of drawing one can prepare using AutoCAD. It is very successfully applied in areas such as

1) Architectural drawings2) Interior design & facility planning3) Drawings of various engineering applications in mechanical, electrical, civil,

automobile, chemical and electronics engineering 4) Technical illustrations & assembly drawings.5) Graphs & plates of all kinds.6) Geometric modeling.

DEVELOPMENT OF AUTO CAD:

The computer aided drafting system; AUTO CAD was launched in December 1982 by Autodesk Inc. of USA (version 1.0). Additional features and facilities were added and enhanced versions followed one another in quick succession release 2.1 in May 1984, version 2.1 in May 85, version 2.5 in June 86 & version 2.6 in 87. The latest version is AutoCAD 2010 which is its 24 th

release.

SYSTEM REQUIREMENT:

AutoCAD runs on a wide range of low cost industry standard computers. AutoCAD files are compatible between different market types & their operating systems. You can easily exchange information between different computer systems. AutoCAD supports a wide range of peripheral devices including digitizers, mice, high resolution display monitors, pen plotter, dot matrix printers, electromagnetic plotters etc…


The following are the system requirements for running AutoCAD 2012

1) Intel Core I-3 or later, with 2.20 GHz or faster processor, or compatible2) Microsoft Windows XP (Professional, Home Edition, or Tablet PC Edition)3) Windows 2000, or Windows 7,8 or 10 4) 2GB RAM5) 3 GB free disk space for installation6) 1024x768 VGA with true colour (minimum)7) Microsoft Internet Explorer , chrome or Mozilla Firefox8) Mouse, trackball, or compatible pointing device

Optional:

1) Printer or plotter 2) Digitizer 3) Serial or parallel port4) Network interface5) Modem or access to an internet connections


CHAPTER 2:

BASIC FACILITIES IN AUTOCAD

The release 2012 screen is shown in fig1. This has the familiar windows look and feel, in

terms of the various buttons and an easier interface. It has set of dropdown windows for

various menu options. From among them:

New: This allows for starting a new drawing.

Open: This allows opening an old drawing for editing.

Save: Allows saving the current drawing.

Save as: Allows saving the current drawing with new name.

Export: Allows for exporting the current drawing into other format. Suitable for other

programs such as….3D studio.

Eg:-

BMP: Device-independent bit map.

DWG: AutoCAD drawing file.

DWF: AutoCAD drawing web format.

DXF: AutoCAD R14 drawing inter change.

SCREEN DISPLAY:-

From fig1.the status line is the bottom most line. On the right side a column is displayed

for providing the possible menu selections. The column can be removed from the screen

if necessary by changing the option in the AutoCAD set up. At the bottom a command

area is provided which is generally designed for three lines. Rest screen is designed as

the drawing area.


Fig 1

MENU:- AutoCAD is a completely menu driven system. Also no. of menu commands available are many. Direct command entry.

Through the side bar menu.

Through the pop-up window from the menu bar.

Through the button bars located in any portion of the screen.(fig2)

PLANING FOR A DRAWING:- This is carried out by set up operations. UNITS:- This lets us set up the units in which the AutoCAD would have to work. It would be working in default co-ordinates called as drawing units. This is achieved by using “units” command. [fig3] It offers following types of units. Scientific.

Decimal.

Engineering.

Architectural.

Fractional.


CO-ORDINATE SYSTEM:- It generally uses the rectangular Cartesian co-ordinate system which follows right hand rule. It also uses rectangular co-ordinate system designed as x, y, & z axis. Co-ordinates can be imputed into the system in a no of ways by direct input of co-ordinate values in their respective order. COMMAND: LINE<LR> FROM POINT: 3.5, 12.0<LR> CR: Carriage return.

LIMITS: It is normally necessary to specify the limits of the drawing that one is about to use. The actual size of drawing would have to be specified using limit command. Limits establishes the size of the drawing and the associated drawing guide such as grids, rullers etc……in proper format. However, limits check option is kept on, and then AutoCAD would not allow you to specify any point beyond the limits.

GRID:- Working on a plane drawing area s difficult since there is no means for the user to understand or correlate the relative position or straightness of the various objects or entities made in the drawing. The grid command controls the display of a grid of alignment to assist the placement of objects in the drawing.

SNAP:- The resolution of the cursor can be effectively controlled by using SNAP command. When the cursor is moving in the drawing area, it moves in increments of the snap spacing value specified. This is useful for inputting data through the digester or mouse. Functional key: F9

ORTHO:- It allows to control “orthogonal” drawing mode. As a result all lines and traces drawn while this mode is on are constrained to be horizontal or vertical. Functional key: F8

HELP:- AutoCAD provides complete help at any point of working in the program.


OBJECT PROPERTIES:-

LINE TYPE: AutoCAD allows the user to draw various types of lines in the drawing. To change the line type of existing object, use the “CHANGE “command. To control large line type use “LAYER” command. It can also load line type definitions from a library file.


Chapter 3 :

Basic AutoCAD Commands -2DBASIC GEOMETRIC COMMANDS:-

The various entities that can be used for making an AutoCAD drawing in 2D are:

POINT

LINE

ARC

CIRCLE

ELLIPSE

POLYGON

POLYLINE

DOUGH NUT

SKETCH

TEXT

BLOCK


POINT:- It is used to specify a point or a node in the drawing for any given purpose. It is also used as NODE in object snap option. It is also possible to specify the co-ordinates in incremental format as the distance from the current cursor position in the drawing area. The distance is specified by using the “@” parameter before the actual value. COMMAND: POINT<CR> Co-ordinates of point: @34.5, 12.0<CR> LINE:-


It allows you to draw straight line. You can specify the desired end points using either 2D

or 3D co-ordinates. To erase the latest line segment without exiting the line command

enters “U”.

Lines may be constrained to horizontal or vertical by the “ORTHO” command. The close

option uses the start point of the first line in the current line command.

CIRCLE:-

It is used to draw a full circle. We can specify a circle in many ways. For specifying the

circle we need at least two values.

• Centre point and radius. • Centre point and diameter. • 2p\3p\ttr methods.

ARC:- It enables to draw an arc as specified by following methods.

Three points on the arc.

• Start point, centre and end point.

• Start, centre and included angle.

• Start, centre and length of chord.

• Start, end and radius.

• Start, end and included angle.

• Start, end and direction of start.

The arc is always drawn in counter clock wise direction. Depending on the data available

it is necessary to plan carefully the sequence in which the data is specified.Drawing a

circle is easier than arc. The arc will be generated n which the points are specified.

LAYERS:-

A layer is basically one which contains some information which can be geometric or

alpha-numeric. The reason of distributes all the information present in the drawing into

various layers is that at any given time some of the layers can be deleted from the

view(off) or can be made visible(on). This helps in organizing the information in a

drawing. Thus each layer may be considered as a transparent sheet having some

information.

• Each layer has a name which can be up to 31 characters.

• Default layer name given by AutoCAD is 0.


• A layer could be ON or OFF. When a layer is ON the information present in it

would be visible on screen.

• A layer is either “current or inactive”.

• If the current layer is ON then the information being entered would be visible on

screen.

• Each layer has a colour associated with it. The colour of individual information can

be altered by using “CHANGE” command or by using “COLOR” command.

ZOOM:- Zoom is used to change the scale of display. This can be used to magnify a part of the drawing to any higher scale of or closely observing some file details in the drawing. There are no. of options available within zoom. SCALE<X>: A numeric zoom factor. A value less than 1 zoom out and greater than 1 zoom in. ALL : Zoom out to original drawing limits. DYNAMIC: Graphically selects any portion of the drawing as your next screen view. CENTRE : Pick a centre and picture top and bottom by selecting two end points of height. EXTENTS: Shows everything in the file. LEFT : Pick a lower left corner and a height of how much drawing information you want to Display to fill up the screen. PREVIOUS: Restores the last zoom setting. Choosing the dynamic option displays all the drawing up to limits in a small window. So that the entire drawing is visible in the display screen. The current visible window would be shown in rectangular linked to the cursor.

PAN:- It allows you to move the display window in any direction without changing the display

magnification. This means the display being seen is through a window in an opaque

sheet covering the drawing limits.

OBJECT SNAP:-

By selecting the OSNAP option the system would be able to automatically calculate the

tangent point in the region selected. The various OSANP options are as follows…..

CENTRE: center or arc or circle

ENDPOINT: closest end point if line/arc etc….

INSERTION: insertion point of text/block etc…

INTERSECTION: intersection of lines/arcs/circles etc…


MIDPOINT: midpoint of lines/arcs/circles etc…

NEAREST: nearest point on line/arc/circle.

NODE: nearest point entity.

PERPENDICULAR: perpendicular to line/arc/circle.

QUADRANT: quadrant point of arc or circle.

TANGENT: tangent to arc or circle.

TEXT HANDLING:-

AutoCAD provides a large range of text entering capabilities including various fonts and

other text handling features.

EDITING A DRAWING:-

Editing capabilities are the most useful part of AutoCAD to export the productivity

potential, making use of the already existing objects in the drawing.

ARRAY: places multiple copies of objects with a single command.

BREAK: cuts existing objects and /or erase portions of objects.

CHANGE: Changes spatial properties of some objects.


COPY: makes copies of objects.

ERASE: Allows selecting objects in the drawing file and erasing them.

MIRROR: creates a mirror image.

MOVE: picks up existing objects and puts them in another location of drawing.

ROTATE: Turns existing object to any angular position.

SCALE: Scales object up or down to your specification.

MOVE:- It is used to move one or more existing drawing entities from one location to

another location. You can draw the object into position on the screen by giving base

point and second point. The selected objects will follow the movements of the screen

crosshair.

OBJECT: the default selects a set by picking individual objects.

WINDOW: objects are completely inside a window drawn by the cursor control device.

LAST: uses only the last object created.

CROSSING: works like a window, it also includes any object which is partially within the

Window

REMOVE: it removes any objects that are accidentally selected by any of the object.

ADD: used o adding when the remove option is specified.

MULTIPLE: allows multiple objects in close proximity.

PREVIOUS: adds the entire previous selection list to the current selection list.

UNDO: undo the last selection operation.

SELECT ALL: selects all objects in drawing.

WINDOW POLYGON: Here, rectangular window is replaced by polygon of as many

vertices as required.

CROSSING POLYGON: similar to the window polygon except that the polygon here is

not would be selected.

COPY:- This command is used to duplicate one or more existing drawing entities at

another location without erasing original. You can drag the object into position on the

screen. The selected object will follow the movements of the screen cross hairs.

To make multiple copies, respond to the base point prompt with „M‟. when you have

made required number of copies give a null response to the second point prompt to

come out of the copy command.


CHAMFER:- It creates a bevel between two intersecting lines at a given distance from

their intersection. It can also trim the lines from the bevel edge and connect the trimmed

ends with a new line of TRIMMODE variable is set to 1. Chamfer can only be applied

between line segments and not any other objects.

FILLET:- It connects two lines, arcs, or circles with a smooth curve of specified radius. It

adjusts the length of the original line or arcs so they end exactly on the fillet arc. The fillet

valve specified remains in force until it is altered by another valve. If the fillet radius is „0‟

then two lines will meet exactly at a point which is normally used to make a sharp corner.

Filleting can also be done to two circles, a line and a circle, a line and an arc and a circle

and an arc.

OFFSET:- This command constructs an entity parallel to another entity at either a

specified point. You can OFFSET a line, arc, circle or polygon. Offset lines are parallel,

while the offset circles and arcs make concentric circles. Once object is selected it is

highlighter on the screen.

ARRAY:-

It makes multiple copies of selected objects in a rectangular or polar pattern.

For a rectangular array you are asked for the no. of columns & rows and the spacing

between them. The array is built along a base line defined by the current snap rotation

angle set by the “SNAP ROTATE” command.

For polar array a centre point needs to be supplied. Following this, you must supply two

of following…

• The number of items in the array.

• The number of degrees to fill

• The angle between items in the array.

DIMENSIONING:-

After creating the various views of the model or after preparing the drawing it is

necessary to add dimensions at the appropriate places. AutoCAD provides semi

automatic dimensions. As a result once dimensions is created. AutoCAD gives great

control over the way dimensions may appear in the drawing. The dimension familiars are

as follows…


Linear

Diameter

Radial

Angular

Ordinate

Leader

Aligned


CHAPTER 3Basic AutoCAD Commands: 3D

3D- MODELING

Creates 3D polygon mesh objects in common geometric shapes that can be hidden,

shaded, or rendered.

Command entry: 3d

Enter an option

[Box/Cone/DIsh/DOme/Mesh/Pyramid/Sphere/Torus/Wedge]:

1.BOX

Creates a 3D box polygon mesh.

Specify corner point of box:

Specify length of box: Specify a distance

Specify width of box or [Cube]: Specify a distance or enter C

Width

Specifies the width of the box.

Enter a distance or specify a point relative to the corner point of the box

Specify height of box: Specify a distance

Specify rotation angle of box about the Z axis or [Reference]: Specify an angle or enter r

Rotation Angle Rotates the box about the first corner specified. If you enter 0, the box

remains orthogonal to the current X and Y axes.

Reference Aligns the box with other objects in the drawing or relative to an angle you

specify. The base point for the rotation is the first corner of the box.Specify the reference

angle <0>: Specify a point, enter an angle, or press Enter


You can define a reference angle by specifying two points or an angle from the X axis on

the XY plane. For example, you can rotate the box to align two specified points on the

box with a point on another object. After defining a reference angle, specify a point for

the reference angle to align with. The box then rotates around the first corner relative to

the angle of rotation specified for the reference angle.

If you enter 0 as a reference angle, the new angle alone determines the rotation

of the box.

Specify the new angle: Specify a point or enter an angle

2.CUBE

Creates a cube using the length for the width and height of the box

Specify rotation angle of box about the Z axis or [Reference]: Specify an angle or enter r

Rotation Angle Rotates the cube about the first corner of the box. If you enter 0, the box

remains orthogonal to the current X and Y axes.

Reference Aligns the box with other objects in the drawing or relative to an angle you

specify. The base point for the rotation is the first corner of the box.

Specify the reference angle <0>: Specify a point, enter an angle, or press Enter

You can define a reference angle by specifying two points or an angle from the X axis on

the XY plane. For example, you can rotate the box to align two specified points on the

box with a point on another object.

After defining a reference angle, specify a point for the reference angle to align with. The

box then rotates around the first corner relative to the angle of rotation specified

for the reference angle. If you enter 0 as a reference angle, the new angle alone

determines the rotation of the box.

Specify the new angle: Specify a point or enter an angle

To specify the new angle of rotation, specify a point relative to the base point. The base

point for the rotation is the first corner of the box. The box rotates the angular distance

between the reference angle and the new angle. If you want to align the box with another

object, specify two points on the target object to define the new angle of rotation for the

box. If the reference angle of rotation is 0, the box rotates the angular distance entered

relative to the first corner point of the box.

3.CONE


Creates a cone-shaped polygon mesh

Specify center point for base of cone: Specify a point (1)

Specify radius for base of cone or [Diameter]: Specify a distance or enter d

Radius of top

Defines the top of the cone by its radius. A value of 0 produces

a cone. A value greater than 0 produces a truncated cone.

Specify height of cone: Specify a distance

Enter number of segments for surface of cone <16>: Enter a value greater than 1 or

press Enter

Radius for Base

Defines the base of the cone by its radius.

Specify radius for top of cone or [Diameter] <0>: Specify a distance, enter d, or press

Enter


press Enter

Diameter for Top Defines the top of the cone by its diameter. A value of 0 produces a

cone. A value greater than 0 produces a truncated cone.

Specify diameter for top of cone <0>: Specify a distance or press Enter



press Enter

Diameter for Base

Defines the base of the cone by its diameter.

Specify diameter for base of cone: Specify a distance

Specify radius for top of cone or [Diameter] <0>: Specify a distance, enter d, or press

Enter

Radius for Top Defines the top of the cone by its radius. A value of 0 produces

a cone. A value greater than 0 produces a truncated cone.



press Enter


Diameter for Top Defines the top of the cone by its diameter. A value of 0 produces a cone.

A value greater than 0 produces a truncated cone.

Specify diameter for top of cone <0>: Specify a distance


Enter number of segments for surface of cone <16>: Enter a value greater than 1 or press

Enter

4.PYRAMID

Creates a pyramid or a tetrahedron.

Specify first corner point for base of pyramid: Specify a point (1)

Specify second corner point for base of pyramid: Specify a point (2)

Specify third corner point for base of pyramid: Specify a point (3)

Specify fourth corner point for base of pyramid or [Tetrahedron]: Specify a point (4) or enter t

Fourth Corner Point

Defines the fourth corner point of the base of a pyramid.

Specify apex point of pyramid or [Ridge/Top]: Specify a point (5) or enter an option.

The Z value of the point specified determines the height for the pyramid's apex, top, or ridge

line.

Apex Point Defines the top of the pyramid as a point (apex).

Ridge Defines the top of the pyramid as a ridge line. The two endpoints must lie in the

same direction as the base points to prevent a self-intersecting wireframe.

Specify first ridge end point of pyramid: Specify a point (1)

Specify second ridge end point of pyramid: Specify a point (2)


Ex.no.: CREATION OF SIMPLE OBJECTS

Date:

Aim:

To create simple objects like polygon and general multi-line figures using0

Auto CAD software.

Software Used:

Auto CAD 2012

Commands Used:

Limits, Zoom, Line, Arc, Circle, co-ordinate systems, Dimlinear

Procedure:

1) Limits are set for A4 standard drawing size. Margins are drawn using lines.

2) Using Line command and appropriate co-ordinate system, the given figures

are drawn and aligned

3) The drawn figures are dimensioned using respective DIM command.

4) Title Block is drawn for the given dimension.

5) Finished work sheet is saved and hard copy is taken.

Result:

The given simple figures like polygon and general multi-line figures are drawn

using Auto CAD software.


Ex.no.: SPECIAL CURVES

Date:

Aim:

To create special curves like parabola, spiral, involute (square and Hexagon)

using Bspline or Cubic Spline using Auto CAD software.

Software Used:

Auto CAD 2008

Commands Used:

Limits, Zoom, Line, Polygon, Arc, Circle, Offset, Copy, Move, Trim, Pline,

Pedit, DIM

Procedure:

1) Limits are set for A4 standard drawing size. Margins and title block are

drawn using lines.

2) From the given data, the Loci points of Parabola are found and joined using

Pline and then fitted using Pedit command

3) From the given data, the Loci points of square and hexagonal involutes are

found and joined using arc command.

4) From the given data, the Loci points of Spiral are found using Concentric

circles or arc method, and joined using Pline and then fitted using Pedit

command.

5) Drawn curves are dimensioned appropriately.


Result:

The special curves like parabola, spiral, involute (square and Hexagon) using

Bspline or Cubic Spline are drawn using Auto CAD.


Ex.no.: PROJECTION & SECTION OF SIMPLE SOLIDS

Date:

Aim:

To draw front and top view of given simple solids (prisms and pyramids) using

Auto CAD software.

Software Used:

Auto CAD 2012

Commands Used:

Limits, Zoom, Line, Polygon, Arc, Circle, Offset, Copy, Move, Trim, Layer,

DIM, Mtext.

Procedure:


drawn using lines.

2) Using Line, Circle, Polygon commands, front and top view of given simple

solids are drawn

3) Layer is defined (for line type, line weight and colour) sepeartely for

visible, hidden, axis and dimension lines and applied.

4) Sectional views are drawn and section is created using Hatch command.

5) Drawn solids are named and dimensioned accordingly.


Result:

The front and top views of the given simple solids (prisms and pyramids) are

drawn using Auto CAD.


Ex.no.: ORTHOGRAPHIC VIEWS OF SOLIDS

Date:

Aim:

To draw the orthographic views from the given pictorial views using Auto

CAD software.

Software Used:

Auto CAD 2012

Commands Used:


DIM.

Procedure:


drawn using lines.

2) Using appropriate commands, front, top and Left side view of given solids

are drawn.

3) Layer is defined (for line type, line weight and colour) sepeartely for

visible, hidden, axis and dimension lines and applied.

4) Drawn solids are dimensioned accordingly.


Result:

The orthographic views of the given solids are drawn using Auto CAD.


Ex.no.: ISOMETRIC VIEWS OF OBJECTS

Date:

Aim:

To draw the isometric view of given simple solids and objects using Auto

CAD software.

Software Used:

Auto CAD 2008

Commands Used:


DIM, Mtext

Procedure:


drawn using lines.

2) Using Line, Circle, Polygon commands, front and top view of given simple

solids are drawn.

3) Snap is changed from Rectangular to Isometric to help draw the Isometric

view. F5 key is used to invoke/toggle between the different Isoplanes

(Left, Top, Right) accordingly.

4) Given objects are taken and drawn in Isometric.

1) Drawn solids are named and dimensioned accordingly.


Result:

The Isometric view of the given simple solids and objects are drawn using

Auto CAD.


Ex.no.: 3D MODELING OF SIMPLE SOLIDS

Date:

Aim:

To create 3-D Models of given simple solids and obtain 2-D multi view

drawings Auto CAD software.

Software Used:

Auto CAD 2008

Commands Used:

Zoom, Line, Polygon, Arc, Circle, DIM, Extrude, Revolve, Pyramid.

Procedure:

1) Auto CAD 3-D template is opened for creating 3-D models.

2) Prisms are created using Extrude command and pyramids by Pyramid

command.

3) Objects of revolution like cylinder and cone are created using Revolve

command.


Result:

3-D Models of given simple solids are created using Auto CAD.


Ex.no.: 2D MULTIPLE VIEWS FROM 3D MODEL

Date:

Aim:

To create a Title Block with necessary text and projection symbol using Auto

CAD software

Software Used:

Auto CAD 2008

Commands Used:

Limits, Zoom, Line, Circle, Layout, Text, Mtext

Procedure:

1) Limits are set for A4 standard drawing size. are drawn.

2) Given Solid is modeled using Extrude command.

3) Layout is created with four viewports for Front, Top, Left Side and

Isometric views.

4) Dimensioning is done in the appropriate views.


Result:

2D multiple views were obtained for the given solid using Auto CAD

software.


Exp: No:

AIM: To develop the given model by using auto cad 2D commands and to specify its

Dimension.

SOFTWARE REQUIRED: - AUTOCAD 2012 Database.

COMMANDS IN USE: - LIMITS,ZOOM,LINE, DIMLINEAR.

PROCEDURE: - In order to obtain given model the following procedure will be

followed…

COMMAND: - Limits:

Specify lower left corner : (0,0)

Specify upper right corner : (150,100)

Command: ZOOM:[All/Center/Previous/Scale/Window/Object] : All

Command: LINE:

Specify first point: 0, 0

Specify next point or (undo): 100[00]

Specify next point or (close/undo): 20[900]



Specify next point or (close/undo):20[1800]

Specify next point or (close/undo):120[2700]


Specify next point or (close/undo): C

Specify next point or (close/undo): ESC

Command: DIMLINEAR

By using this command give dimensions linearly for drawn object to indicate its

Linear dimensions.

PRECAUTIONS:-

1. Limits should be given before drawing the object.

2. Object should be drawn from a specific point of location only.

3. Ensure that proper sequence should be followed to draw an object.

RESULT:

Hence by using auto cad 2012 2D commands we have drawn the object model and

Dimensions are specified.


EXP NO:

AIM: To develop the given model by using auto cad 2D commands and to specify it‟s

Dimension.


COMMANDS IN USE: - LINE, CIRCLE, DIMLINEAR, DIMDIA.


followed…

COMMAND: - Limits:

Specify lower left corner : (0,0)

Specify upper right corner : (150,150)

Command: ZOOM:[All/Center/Previous/Scale/Window/Object] : All

Command: LINE:

Specify first point: 0, 0

Specify next point or (undo): 150[00]



Specify next point or (close/undo): C

Specify next point or (close/undo): ESC

Command: CIRCLE

Specify centre point for circle (3p/2p/ttr): 30,30

Specify radius of circle or (diameter): d

Specify diameter of the circle: 10

Command: CIRCLE




Command: CIRCLE




Command: CIRCLE





Command: DIMLINEAR

By using this command give dimensions linearly for drawn object to indicate it‟s

Linear dimensions.

PRECAUTIONS:-




RESULT:




EXP NO:

AIM: To draw the isometric drawings by using AutoCAD 2012 2D commands and the

Dimensions can be determined by counting the no of grids.

SOFTWARE REQUIRED: - AutoCAD 2012 Database.

COMMANDS USED: LIMITS, ZOOM,LINE, DIMLINEAR.

PROCEDURE: Highlight the grid option.

COMMAND: LIMITS

Specify lower left corner: 0, 0

Specify upper left corner: 300,300

ZOOM:[All/Center/Previous/Scale/Window/Object] : All

Command: LINE.

Polar: on setting 30 c

Specify the first point: 0,0

Specify the next point: 24[1500]


Specify the next point:24[300]






Specify the next point: c









Specify the next point:c

Command: DIMLINEAR


Linear dimensions.

PRECAUTIONS:-




RESULT:


Dimensions are specified .

.


EXP NO:

AIM: To draw the isometric drawing by using AutoCAD 2D drawing commands.

SOFTWARE REQUIRED: - AutoCAD 2012 Database.

COMMANDS: LINE, LIMITS

PROCEDURE: change the view to isometric view.

COMMAND: LIMIT

Specify the lower left corner: 0, 0

Specify the upper right corner: 200,200


COMMAND: LINE


Specify the first point: 0,0













Specify next point or (close/undo): c

Command: DIMLINEAR


Linear dimensions.

PRECAUTIONS:-





RESULT:




EXP NO:

AIM: To develop the given model by using auto cad 2D commands and to specify its

Dimension.


COMMANDS IN USE: - LINE, LIMITS, DIMLINEAR


followed…

COMMAND: LIMIT

Specify the lower left corner: 0, 0

Specify the upper right corner: 200,200


COMMAND: LINE


Specify the first point: 0, 0



















Specify next point or (close/undo): c

Command: DIMLINEAR


Linear dimensions.

PRECAUTIONS:-




RESULT:





Documents

BTech Lab Manual Autocad