LAB MANUAL

LAB MANUAL ME-241

(Mechanical Engineering Drawing & Graphics)

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Introduction to computer aided drafting and solid modeling: software and

hardware.

Understand basic 2D geometric construction techniques.

1. Cartesian and polar coordinate systems: locating points, coordinate entry

methods, units and limits.

2. Object generation: lines, arcs, polylines, and multiline; rectangles, circles,

polygons, and ellipses.

3. Transformations: move, copy, rotate, scale, mirror, offset and array; trim,

extend, fillet, chamfer.

4. Layers: creation, naming, properties manager.

5. Blocks: create, edit, import and explode.

6. Text: creating and editing, formatting, text styles.

7. Dimensions: creating and editing, dimension styles.

Exercise on basic drafting principles to create technical drawings.

1. Create orthographic views of machine parts from pictorial views.

2. Create isometric views of machine parts from orthographic views

3. Create hatched sectional views of machine parts.

Mechanical Engineering Drawing & Graphics

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Jouf University Academic Dishonesty Policy

Student Conduct: Penalties for academic dishonesty will be severe. Academic dishonesty

includes cheating, plagiarism or sabotage. Cheating includes but is not limited to: (i)

unauthorized assistance in taking quizzes, tests or examinations; (ii) dependence upon the aid of

sources beyond those authorized by the instructor in solving problems or carrying out other

assignments; (iii) acquisition or possession without permission of tests or other academic

material belonging to a member of the faculty or staff; (iv) knowingly providing any

unauthorized assistance to another student on quizzes, tests or examinations.

Plagiarism includes, but is not limited to: (i) use by paraphrase or direct quotation of the

published or unpublished work of another person without fully and properly crediting the author

with references; (ii) unacknowledged use of materials prepared by another person or agency

engaged in the selling of term papers or other academic materials; or (iii) unacknowledged use of

original work/material that has been produced through collaboration with others without release

in writing from collaborators.

Sabotage includes but is not limited to, the unauthorized interference with, modification of, or

destruction of the work or intellectual property of another member of the University community.

Other conduct that is subject to disciplinary action includes the actual or attempted theft or other

abuse of computer time, including but not limited to: (i) unauthorized entry into a file to use,

read or change the contents, or for any other purpose; (ii) unauthorized transfer of a file; (iii)

unauthorized use of another individual's identification and password; (iv) use of computing

facilities to interfere with the work of another student, faculty member or University official; (v)

use of computing facilities to interfere with normal operation of the University computing

system; (vi) knowingly causing a computer virus to become installed in a computer system or

file.

For this class, work turned in must be original and represent an individual effort unless otherwise

indicated. IF DUPLICATE COPIES OF PROJECTS OR HOMEWORKS ARE RECEIVED, AN

AUTOMATIC GRADE OF ZERO WILL BE GIVEN TO ALL PARTIES INVOLVED. Code

which is not your own must be referenced (e.g. when using code libraries). Persons observed

cheating on tests will forfeit the test and receive a zero for that test. Names of persons involved

in any of these incidents will be forwarded to the Head of the Department. Those students will be

subject to sanctions as outlined in the general catalog. Sanctions may result in dismissal from the

University.

I have read and I understand the Class Policies regarding Student Conduct. I agree to abide by

these policies.

Signed: Date:

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GENERAL GUIDELINES AND SAFETY INSTRUCTIONS

This section discusses safety in the lab. Safety guidelines help protect individuals from accidents

and injury. They also help to protect equipment from damage. Some of these guidelines are

designed to protect the environment from contamination caused by improperly discarded

materials.

General Safety

Safe working conditions help prevent injury to people and damage to computer equipment. A

safe workspace is clean, organized, and properly lighted. Everyone must understand and follow

safety procedures.

Follow the basic safety guidelines to prevent cuts, burns, electrical shock, and damage to

eyesight. As a best practice, make sure that a fire extinguisher and first-aid kit are available in

case of fire or injury. Poorly placed or unsecured cables can cause tripping hazards in a network

installation. Cables should be installed in conduit or cable trays to prevent hazards.

This is a partial list of basic safety precautions to use when working on a computer:

Remove your watch and secure loose clothing.

Turn off the power and unplug equipment before performing service.

Cover sharp edges inside the computer case with tape.

Never open a power supply or a CRT monitor.

Do not touch areas in printers that are hot or that use high voltage.

Know where the fire extinguisher is located and how to use it.

Keep food and drinks out of your workspace.

Keep your workspace clean and free of clutter.

Bend your knees when lifting heavy objects to avoid injuring your back.

Electrical Safety

Follow electrical safety guidelines to prevent electrical fires, injuries, and fatalities in the home

and the workplace. Power supplies and CRT monitors contain high voltage.

CAUTION

Do not wear the antistatic wrist strap when repairing power supplies or CRT monitors.

Only experienced technicians should attempt to repair power supplies and CRT monitors.

Some printer parts become hot during use, and other parts might contain high voltage. Check the

printer manual for the location of high-voltage components. Some components retain a high

voltage even after the printer is turned off. Make sure that the printer has had time to cool before

making the repair.

Electrical devices have certain power requirements. For example, AC adapters are manufactured

for specific laptops. Exchanging power cords with a different type of laptop or device may cause

damage to both the AC adapter and the laptop.

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Fire Safety

Follow fire safety guidelines to protect lives, structures, and equipment. To avoid an electrical

shock and to prevent damage to the computer, turn off and unplug the computer before beginning

a repair.

Fire can spread rapidly and be very costly. Proper use of a fire extinguisher can prevent a small

fire from getting out of control. When working with computer components, be aware of the

possibility of an accidental fire and know how to react. Be alert for odors emitting from

computers and electronic devices. When electronic components overheat or short out, they emit a

burning odor. If there is a fire, follow these safety procedures:

Never fight a fire that is out of control or not contained.

Always have a planned fire escape route before beginning any work.

Get out of the building quickly.

Contact emergency services for help.

Locate and read the instructions on the fire extinguishers in your workplace before you

have to use them.

Be familiar with the types of fire extinguishers used in your country or region. Each type of fire

extinguisher has specific chemicals to fight different types of fires:

Paper, wood, plastics, cardboard

Gasoline, kerosene, organic solvents

Electrical equipment

Combustible metals

It is important to know how to use a fire extinguisher. Use the memory aid P-A-S-S to remember

the basic rules of fire extinguisher operation:

P: Pull the pin.

A: Aim at the base of the fire, not at the flames.

S: Squeeze the lever.

S: Sweep the nozzle from side to side.

In case of emergency, call campus security or 911.

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1- AutoCAD Commands ……………………………………………………Page 7

2- AutoCAD 2D Drawings ……………………………………...………….Page 11

3- AutoCAD 3D Drawings …………………………………………………Page 16

4- Mechanical Drawings …………………………………...……………….Page 22

5- Mechanical Assembly Drawings ………………………………….……..Page 25

Contents

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AutoCAD Commands

Draw Commands

Command Shortcut Function

Line L Draw a line

Polyline PL Draw a Polyline

Polygon POL Draw a regular polygon 3 to 1024 sides

Rectangle REC Draw a rectangle

Arc A Draw an arc between 2 intersecting lines

Circle C Draw a circle

Ellipse EL Draw an ellipse

Block B Opens block dialogue box in order to make a block

Table TB Opens insert a table dialogue box

Point PO Point marker

Hatch H Opens hatch and gradient dialogue box

Text MT Multi-line text

Modify Commands


Erase E Erase selection

Copy CO Copy an object Mirror MI Mirror an object Offset O Offset an object by distance Array AR Make multiple copies of an object Move M Move an object Rotate RO Rotate an object Scale SC Scale an object

Stretch S Stretch an object

Lengthen LEN Lengthen or shorten a line

Trim TR Trim objects

Extend EX Extend a line to meet another

Break BR Break a line by defining 2 points

Join J Joins 2 objects to form single object

Chamfer CHA Chamfer between two unparalleled lines

Fillet F Draw an arc between 2 intersecting lines

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Dimensions Commands


Linear DLI Linear dimension

Align DAL Aligned linear dimension line

Arc length DAR Arc length dimension

Ordinate DOR Ordinate point dimension Radius DRA Radial dimension for circles and arcs Diameter DDI Diameter dimension for circles and arcs

Angular DAN Angular dimension line

Base line DBA Ordinate dimension from baseline of previous dimension

Continue DCO Ordinate dimension from 2nd extension line of previous

dimension

Distance DIST Check a distance

Centre DIMCENTER Creates center mark

Override DOV Override dimension style

Function Commands


HELP F1 Opens AutoCAD help

OSNAP F3 Switches OSNAP on/off

ISOPLANE F5 Cycles through ISOPLANES

COORDS F6 Turns COORDINATE display on/off GRID F7 Turns GRID on/off ORTHO F8 Turns ORTHO on/off

SNAP F9 Turns SNAP on/off

POLAR F10 Turns POLAR on/off

OSNAP TRACK F11 Turns OBJECT SNAP TRACKING on/off

DYNMODE F12 Turns DYNAMIC INPUT on/off

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Commands Details

LINE

Draw – line – click first point – give require length – TAB – give require angle – enter –

enter.

RECTANGLE:

Draw – rectangle – click first point – give require length – TAB – give require height –

enter.

CIRCLE:

Draw – circle – click center point – give require radius – enter.

COPY:

Modify – copy – select object to copy – entre – select base point – select second point – esc.

MIRROR:

Modify – mirror – select object to mirror – entre – click first point of mirror line – click

second point of mirror line – entre.

OFFSET:

Modify – offset – give offset distance – entre – select object to offset – select side to

offset – esc

MOVE:

Modify – move – select object to move – entre – select base point – select second point – esc.

ROTATE:

Modify – rotate – select object to rotate – entre – select base point – give angle of

rotation – enter.

SCALE:

Modify – scale – select object to scale – entre – select base point – give scale factor –

entre.

TRIM:

Modify – trim –SPACE – select line to be trim – enter.

EXTEND:

Modify – extend –SPACE – select line to be extend – enter.

FILLET:

Modify – fillet – type R – entre – give fillet radius – entre – select first line – select

second line.

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Various Modes Settings

Snap mode :

ON -

OFF -

Grid display :

ON -

OFF -

Ortho mode :

ON - allows only vertical & horizontal lines

OFF – allows inclined lines also.

Polar tracking :

ON - gives track of angles set in setting of polar tracking.

OFF – does not give any track.

Object snap :

ON - highlights snap points (control points) like end point, midpoint, center point etc.

OFF – does not highlight any snap points.

Object snap tracking :

ON - gives track of points set in setting of object snap.

OFF - does not give any track

Allow/disallow dynamic UCS :

ON -

OFF -

Dynamic input :

ON - displays message (command help) on screen regarding command in use.

OFF – does not display any message on screen.

Show/hide line weight :

ON - shows weight of line if applied.

OFF – does not shows weight of line if applied.

Quick properties :

ON - shows properties of selected object.

OFF – does not show properties of selected object

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AutoCAD 2D Drawings

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AutoCAD 3D Drawings

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Mechanical Drawings

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Mechanical Assembly Drawings

LAB MANUAL

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