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Basic Technology Made Easy

1

Basic Technology

Made Easy 3

This book is in electronic (e) version but may be printed and

assembled in a booklet form by any student or teacher.


Making Learning Fun!

By

Agejivwie Benaiah Orajereyor

Basic Technology Made Easy (http://basictechnologymadeeasy.com/blog

Copyright © 2015 by Basic Technology Made Easy, Inc. All rights reserved

Worldwide. No part of this eBook may be reproduced in any form or by electronic

or mechanical means, including information and retrieval system, without

permission in writing from the copyright holder.

This eBook is distributed at

http://basictechnologymadeeasy.com/blog

This edition is published by Basic Technology Made Easy with the assistance of

Agejivwie Benaiah O.

This eBook is distributed at:

www.bstbasictechnology.wordpress.com

P.O. Box 11264, Surulere-Lagos. (+2348164634883)

[email protected]

www.facebook.com/basictechnologymadeeasy

PREFACE

http://basictechnologymadeeasy.com/blog

http://www.bstbasictechnology.wordpress.com/

mailto:[email protected]

http://www.facebook.com/basictechnologymadeeasy


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This e-series has been designed to reflect the 2014 Nigerian Educational Research

and Development Council (NERDC) National Basic Technology for Junior

Secondary School year 1, 2 and 3.

While preparing this edition, I ensured that where appropriate, review questions

that contain emerging national and global issues such as is available in

engineering, health, information technology and entrepreneurship.

The book has been divided into three broad parts, each showing the scheme for the

term and scaled into lessons for the student and teacher for easy access plus

practical videos for demonstration on geometrical construction-where applicable.

I have retained popular features, such as lesson objectives and exercises . In

addition, this edition contains a most interesting and new feature-the first of its

kind in Nigeria-where the student and teacher has access to practical videos on

Geometrical Construction as contained in the curriculum.

While preparing this edition, I made sure I retained the style and rigour of

imputing illustrations and images in each lesson. Again, at the end of the text

book, there are more than 200 objective test questions for the student and teacher

to revise with.

I wish to express my appreciation to my students I have taught over the past fifteen

(15) years who encouraged me to put up a material like this for them. I also

appreciate a number of teachers far and near, who encouraged me with their

appreciation through the edited copy of this material.

I wish in particular to express my gratitude to Mrs. Adebimpe Delano, the amiable

principal of Fountain Heights Secondary School, for her advice and helpful

guidance.

P.S. I must state that this edition is subject to upgrading as time passes. This is to

meet national and global standard as the curriculum changes especially now that

Basic Technology has been fused into Basic Science and Technology (BST) by

NERDC.

Image Credit: www.googleimage.com

http://www.googleimage.com/


DEDICATION

This book is dedicated to my understanding wife, Nduka,

for believing in me and encouraging me to follow my dreams. She

will always say, “Give Every Dream an Opportunity.”


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TABLE OF CONTENT

PART 1

LESSONS PAGE

1.1. Career Prospects and Opportunities in Technology……………………………….. 8

-Related careers and Employment opportunities.

1.2. Production of Materials………………………………………………………………. 15

i. Processing of Wood and Metals- , Manufactured boards

1.3. Production of materials (Contd.)……………………………………………………... 31

ii. Ceramics, Plastic and Rubber- processing of ceramics, processing of plastics and rubber.

1.4. Pictorial Drawing- Isometric, Oblique and Perspective drawing……………………… 37

1.5. Orthographic Projection………………………………………………………………. 43

- Plan, Front and End views (1st and 3rd Angle projections)

1.6. Wood Work Machines…………………………………………………………………. 46

- Definition

- Types and uses.

1.7. Simple Wood Work Projects…………………………………………………………… 51

- woodwork and uses

- construction of joints e.g. Mortise and Tenon, Halving, etc.

1.8. Metalwork Machines…………………………………………………………………… 63

- Definition

- Types and uses.

1.9. Simple Metalwork Projects……………………………………………………………. 69

- Fabrication process eg

cutting and filling

- drilling process of articles.

1.10. Metal Joining…………………………………………………………………………. 80

- Methods of joining metals e.g, soldering & brazing, welding, riveting and mechanical fasteners

- Tools and Materials used for joining metals.

1.11. Revision………………………………………………………………………………… 86

1.12. Examination……………………………………………………………………………. 86


PART 2

2.1. Mechanical Transmission System……………………………………………………… 86

(i). Friction- Definition and causes of friction

- Laws of friction.

2.2. Mechanical Transmission System (Contd.)……………………………………………. 88

(ii). Effects of Friction (advantages and disadvantages of friction)

- Reduction of Frictional effect.

2.3. Mechanical Transmission System (Contd.)……………………………………………. 92

- Drive mechanism (gears and chain drive)

2.4. Mechanical Transmission System (Contd.)…………………………………………… 100

(iii). Motion in engineering system (types and conversion)

2.5. Mechanical Transmission System (Contd.)…………………………………………... 106

(iv) Air flow- mechanical properties

- appliances based on air flow (pneumatics)

2.6. Simple Electrical Wiring……………………………………………………………….. 112

- schematic diagram of electrical circuit (series and parallel)

- wiring tools and materials.

2.7. Building Construction-Foundation……………………………………………………. 120

- Types and uses

- name types of soil

2.8. Building Construction (Contd.)………………………………………………………... 126

- walls and floors- Definition

- Types and uses.

2.9. Building Construction (Contd.)………………………………………………………... 132

- Doors and windows- Definition

- Types and uses.

2.10. Building Construction (Contd.)………………………………………………………. 140

- Roof- Definition

- Types and Uses.

2.11. Revision………………………………………………………………………………… 146

2.12. Examination…………………………………………………………………………… 146


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PART 3

1. Simple Blue Print Reading……………………………………………………………. 146

- Simple details of a building plan.

2. Periodic Maintenance…………………………………………………………………. 155

- Definition and types

- Method of maintenance e.g. dusting, cleaning, oiling, etc.

3. Periodic Maintenance (Contd.)………………………………………………………. 157

Appliances e.g. Furniture (wood and metal)

4. Periodic Maintenance (Contd.)………………………………………………………. 162

Appliances e.g. electrical/electronics.

5. Fault Detection……………………………………………………………………….. 167

- Definition (trouble-shooting)

- Instrument for fault detection.

6-13.Revision- JSCE! JSCE!! JSCE/ NECO………………………………………… 170-197


LESSON-1.1

CAREER PROSPECTS AND

OPPORTUNITIES IN

TECHNOLOGY

OBJECTIVES: At the end of this lesson, the students should be able to:

1. Define career.

2. List ten careers available for students of technology.

3. State the career functions of the ten careers listed above.

4. Mention areas in Nigeria where students of technology can be gainfully

employed.

What is a Career?

A career can be defined as a profession or job one is trained to do for the rest of

his/her life time. Doing this career brings monetary benefits and fulfillment.

Technology Related Careers

Careers related to technology includes the following in Nigeria:

1. Mechanical Engineering

2. Electrical/Electronic Engineering

3. Civil Engineering

4. Building Engineering

5. Production Engineering

6. Chemical Engineering

7. Computer Engineering

8. Automobile Engineering

9. Metallurgical Engineering

10. Mining Engineering


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11. Petroleum Engineering

12. Aeronautical Engineering.

Importance of Technology Related Careers

1.Mechanical Engineering: The skill and training in this profession has led to the

invention of machines used in transportation, manufacturing, plumbing

installations, pipe-network construction for gas, water and petroleum products. E.g.

Mechanical Engineers at Work.

2. Electrical/Electronics Engineering: The students in this field will be exposed

to instrumentation, control systems, communications, power generation,

transmission and distribution. E.g.

Electrical Panels and Devices

3. Civil Engineering: This field deals with the design, construction and

maintenance of dams, roads, bridges, airports, seaports, etc. e.g.


Road Construction in progress

4. Building Engineering: This is a professional who interprets the plan documents

drawn by an architect, into a physical reality. E.g.

Building Construction in Action

5. Automobile Engineering: This is a field of engineering that deals with the

design, construction and maintenance of automobiles. E.g.

An Automobile Assembly Line.


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6. Aeronautical Engineering: It is a field of study that deals with the design,

construction, flying and the maintenance of aeroplanes. E.g.

Aero-Contractor Hangar at Warri, Delta State.

7. Production Engineering: This is the field of engineering that deals with how to

put different machines together (called assembly lines) used for manufacturing

goods like brewing. E.g.

Production Assembly Line

8. Chemical Engineering: This profession deals with the design, construction,

operation and maintenance of equipment, instruments and plants used for handling

chemical substances. E.g.


A Chemist and Chemical Plant

9. Computer Engineering: Engineers in this field are expected to design, develop,

apply and maintain different grades of computer hardwares and softwares. E.g.

The Computer Doctor.

10. Metallurgical Engineering: These are professionals that focus on the study of

metals, their behavior, characteristics and ways of producing alloys of different

metals that can be used in other engineering fields. E.g.

Strength of material in metals for bridges, rail lines and pipelines.

11. Mining Engineering: This is the study of using earth-moving machines to

uncover and extract underground mineral resources like bitumen, gold, coal, etc.

e.g.


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A Quarry Site

12. Petroleum Engineering: This field deals with the extraction of petroleum and

gas from underground using equipment, rigs and drills with the aid of specialized

skills. E.g.

Off-Shore Oil Rigs

Employment Prospects For Technology Students

The different areas where students of technology can be gainfully employed in

Nigeria include the following:

Private Companies: In Nigeria, there are employment opportunities in most

private industries that render services related to engineering. Manufacturing

companies, banks and other industries also employ technicians and engineers.

Educational Sector: To train future engineers, secondary schools, polytechnics

and universities employ engineers as tutors and lecturers to impart knowledge to

younger ones.

Public Sector: In most government ministries like transportation, science and


technology, power and mining, etc, it is engineers that the government sort after

for gainful employment to man these sectors.

Consultancy: This is a partnership between different fields of engineers providing

services of their choice. These consultancies can employ graduates from diverse

engineering disciplines also.

Independent Practice: Engineering graduates can also set-up personal enterprise

of their choice to employ other graduates so as to earn a living.

NOTE:To succeed as an engineering student, you must be interested and take the

following subjects seriously:

Mathematics, Basic Technology, Physics, Chemistry and Technical drawing.

REVIEW QUESTIONS

1. Define career.

2. List ten careers available for students of technology.

3. State the career functions of the ten careers listed above.

4. Mention areas in Nigeria where students of technology can be gainfully

employed.


15

LESSON- 1.2

PRODUCTION OF MATERIALS

(wood)

OBJECTIVES: At the end of this lesson, the student should be able to:

1. define wood felling.

2. state at least two main areas where wood can be felled in Nigeria.

3. explain wood conversion.

4. define wood seasoning

5. explain at least five reasons why wood is seasoned

6. calculate moisture content of wood

7. states what veneer is

8. state at least 3 methods used for producing veneers.

9. write short notes on how to produce at least 3 types of manufactured

boards.

10. state what wood preservation is

11. explain at least four types of wood defects.

13. what iron–ore is

14. state how pig– iron is produced from iron – ore

15. state at least five types of furnaces for producing steel.

Wood felling: This is the process of cutting down trees in the forest either

manually or mechanically. A felled tree is referred to as log.

Areas Where Trees Can Be Found

In Nigeria, there are two areas where trees can be felled legally. They are:

(i) Free Areas: These are areas owned by families, villages and communities

where mature trees can be felled.


Permission is usually sort from community elders before trees are felled.

(ii) Government Reservation Areas: These are areas controlled by local, state or

federal government. The mature trees in these areas are classified and monitored

by forest guards. Tariff is paid on any tree felled depending on the economic value

of such tree.

Wood Conversion

Wood conversion is the process of splitting log into smaller commercial sizes

either at the sawmill or at the forest.

Methods of Wood Conversion

(i).Plain Sawn: This is the method of cutting log linearly or flatly in a horizontal

manner to produce planks e.g.

Plain sawn method

(ii). Quarter Sawn: This is the method of splitting log angularly along the grains

on the log. It is usually more technical to split wood using this method. E.g.

Quarter sawn method


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Wood Seasoning

This is the process reducing the moisture or water content of wood. Since sawn

timber contain some amount of water, it must be seasoned before using them.

Reasons for Wood Seasoning

(i). Seasoning makes the wood stronger.

(ii) It makes the wood lighter in weight.

(iii) It makes wood to take (absorb) preservatives easily.

(iv) Seasoning makes wood more stable when being used for furniture work

(v) It makes wood more durable.

(vi) Seasoning makes the wood take polish easily.

Calculating Moisture Content

Moisture content is calculated as a percentage respecting the wetness or dryness of

any wood. The general formulae used in calculating moisture content is given as:

Wet weight – dry weight x 100

Dry weight 1

Example: If a sample of wood weighs 60gm before and 40gm after drying, what is

the percentage moisture content?

Solution:

Given that wet weight – Dry weight x 100

Dry weight 1

= 60gm - 40gm x 100

40gm

= 60 – 40 x 100

40 1

= 20 x 100

40 1

= 50%


Defects in Wood

Defects are faults or irregularities in wood caused either naturally or during

processing of the wood which reduces the value or quality of the timber.

1. Natural defects: These are defects which occurs during growth of a tree.

They include the following names:

(a).Knots: A knot is a defect that occurs at the branch of a tree. If a branch falls

from a tree it may leave a knot hole on the tree e.g.

(b).Shakes: This is the complete separation of parts of a stem in a living tree. it

occurs because of stress variation in the stem. There is the ring shake, cup shake,

star shake and the heart shake.

(i). Ring Shake: The plit in this case occurs right around the growth ring. E.g.

(ii). Cup Shake: This is a visible split that goes half round the growth ring. E.g.


19

(iii). Star Shake: This is split that is extending from the pith to the outer section of

a log in a star form. E.g.

Star shake

(iv). Heart shake: This is a split that is restricted to the pith or centre of a tree.

E.g.

2. Artificial defects: This is also referred to as processing defects. It includes

checks and warps.

(a) Checks: This is a defect which creates a separation of wood grain along the

grain board. Eg


Checks

(b) Warps: Twists in timber are called warps. They may be caused by improper

seasoning procedure. E.g.

Twist Bow Cup

(c). Bow: This is a curvature that occurs along the length of a plank. It could be

concave or convex curvature. E.g.

Bow

(d). Twists: This is a spiral distortion in a plank. Wrong stacking method may

cause this twist. E.g.

Twist


21

Wood Preservation

Wood preservation is the process treating wood with solutions so as to make it

poisonous for insects and fungi. The solutions used for this purpose is referred to

as preservatives.

Classes of Preservatives

1. Tar Oils: The distillation of coal tar with kerosene gives birth to a blackish-

yellow solution called creosote. It smells like carbolic acid. It is used on

wood surfaces to protect it against insects and fungi.

2. Water-borne preservatives: These are preservatives made from dissolving

toxic chemicals in water. It prevents termites and fungi from attacking

timber.

3. Solvent preservatives: This type of preservative is obtained when toxic

chemicals are mixed with non-aqueous solvents (solvents that do not contain

water), like spirit (thinner) or petrol.

Methods of Applying Preservatives

i. Open Tank Method: This method involves an open tank or drum

containing the heated preservative to a high temperature of 2000Fand the

wood soaked into it. E.g.

Open tank method

ii. Cold Immersion: This method is slightly different because in this case the

solution is not heated. The wood can be fully immersed or only the butt

ends. E.g.


Cold immersion

iii. Brushing method: This method involves the brushing of the preservative on

the surface of the wood. Penetration is very minimal using this method.

As such it is least effective. E.g.

A furniture maker brushing

iv. Spraying method: This is the use of a spraying machine to apply

preservatives in the form of pigments of stable metallic oxides in paints

to the wood surface. E.g.

Spraying method

Veneer

A veneer is a thin sheet of wood used in the manufacture of boards. It is usually

sliced from log.


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Methods Of Producing Veneers

(i) Slicing Method: The method of using slicing blade to cut off thin leaves from

a particular log. E.g.

Slicing method

(ii) Reeling method: This is the method of peeling log in a continuous rotary

fashion mounted on a machine. The log is usually soften through

steaming first. E.g.

Reeling method

(iii)Eccentric or Sawing Method: In this method the log is cut into quarters. It

is this quarter that is then sliced to veneer. E.g.

Eccentric method

Manufactured Boards

Manufactured boards are man- made boards made from multiple veneers, using

adhesives, sawdust, etc. In Nigeria, the size of common boards is 2440mm by

1220mm.


Types of Manufactured Boards

(i). Plywood: These are boards made from multiple veneers glued together with

adhesives. The veneers are usually arranged so that the grains criss-cross each

other. They are used for partitioning. E.g.

A set of Plywood

(ii). Block boards: This board looks like a flush door. The inner part of this board

contains a strip of timbers forming the core and covered with two layers of

veneers. They are used for flooring and doors. E.g.

Block board

(iii). Laminated boards: These are boards used for high class veneer furniture. It

contains a thinner strip of timber forming the core and glued together. The surface

is glossy. They are used for high-class furniture work. E.g.

Set of Laminated boards


25

(iv). Particle boards: These are boards made from wood chippings glued together

and compressed under heat. It is used for paneling and kitchen furniture work. E.g.

Particle board

(v). Hard boards: These boards are made from the combination of wood waste

(sawdust in Nigeria) and bonded together under high temperature and compression.

They are used for making cabinets. e.g.

Hard board

Advantages of Manufactured Boards

(i). Using a manufactured board produces various large flat sheets of timber.

(ii). Manufactured boards do not check nor warp.

(iii). Manufactured boards can be worked on easily.

Processing of Metal

Introduction:

Metal is processed from a natural solid mineral ore found beneath the earth called

iron-ore. In its natural state iron-ore contains many impurities that is removed

through smelting. E.g.


Sample of Iron-Ore

(i). Blast Furnace: The blast furnace is a smelting (burning) plant used for

processing iron – ore into pig –iron. To smelt iron – ore in the blast furnace, other

chemicals like coke (which serves as fuel) and limestone (which removes

impurities) are added to the iron – ore so that most of the impurities may be

removed. E.g.

Blast furnace

Pig – iron: Pig –iron is the product derived from blast furnace. Further

processing of pig – iron gives birth to steel. The furnace used for this purpose is

called “Bessemer Converter”.


27

Residue of Pig-Iron from Blast Furnace

Bessemer Converter: This is the furnace used for smelting pig – iron into steel by

further burning off of impurities in the right percentage. It was developed by Henry

Bessemer. Since steel is categorized into three groups, the Bessemer converter is

used for this purpose.

A more detailed explanation of how the Bessemer converter works will be covered

in JSS 3. E.g.

Henry Bessemer 1813-1898 The Bessemer Converter

Other Methods: Other furnace used in the smelting of iron – ore into steel are:

The basic oxygen furnace: In this furnace, scrap metal is used to charge the

system before molten metal is introduced. Oxygen is forced into the furnace

through a water-cooled lance. At a point lime is added to act as flux in the furnace

This system is used for producing stainless steel. E.g.


Basic-Oxygen Furnace

Electric-Arc furnace: This furnace has three carbon electrodes which are

electrically powered for heating scrap and molten metal for producing stainless

steel. Lime, fluorspar and iron oxide are added at a point. Depending on the class

of metal to be produced alloying materials are added to a correct proportion. E.g.

Electric Arc Furnace

Open-Hearth furnace: In this furnace pig iron and scrap are stored in a large

hearth. It makes use of hot gas and air to melt the content put into it. Ferro-

manganese is added to make the correct aggregate of stainless steel. E.g.


29

Open-Hearth Furnace

This three methods listed above make use of iron oxide at high temperature (16000

C) to remove impurities from pig iron into steel or stainless steel.

Classes of steel

Low Carbon Steel: The content of carbon In a low carbon steel is about 0.05% -

0.3%. it contains mostly ferrite. It has low tensile strength and is used for car

bodies and light structures.

Medium Carbon Steel: This class of steel mainly contains cementite. This

property makes medium carbon steel hard and ad of great strength. It is mainly

used in making lighter springs and power transmission devices. The carbon con-

tent is about 0.3% - 0.8%.

High Content Steel: This is the steel that contains mostly pearlite. Carbon content

is 0.8% and above. It is usually very hard and it is used for making cutting tools

like files, punches, chisels, dyes, etc.


REVIEW QUESTIONS

1. What is wood felling.

2. Explain the two main areas where wood can be felled in Nigeria.

3. What is wood conversion.

4. Define wood seasoning

5. Explain 5 reasons why wood is seasoned

6. A sample of wood weighed 70gm before and 50gm after drying. Calculate

the moisture content of the wood.

7. What is a veneer?

8. Explain 3 methods used in producing veneers.

9. Write short notes on how to produce 3 types of manufactured boards.

10. What is wood preservation?

11. Explain 4 types of wood defects.

12. Describe the two types of wood defects

13. What is iron–ore?

14. How is pig– iron produces from iron – ore

15. State at least five types of furnaces for producing steel.


31

LESSON-1.3

PRODUCTION OF CERAMICS,

PLASTICS AND RUBBER


(i). Identify the process involved in the production of plastics, rubber and

ceramics.

(ii). Explain with diagrams the processes involved in the production of the

above mentioned materials.

(iii).Explain the different forms involved in the processing of plastics.

(iv).Describe how rubber is processed.

A. Processing of Ceramics

Ceramics are made of different products like clay, cement and concrete.

Pottery Making: The art of making objects from clay is called pottery. Examples

are pots, tiles, sanitary wares, cups, plates and bricks.

Processing of pottery: To use clay in making any item, four different processes

are involved. They are:

1. Excavation Of Clay: Clay is usually excavated from the earth with a shovel.

The clay is then processed so as to remove air bubbles and sand particles, so that it

can be moldable.

2.Molding Of Clay: This is the processing of clay to a particular shape. There are

three basic methods involved. They are:

i. The Pinch Method: This is the method of using the thumb, with the clay

placed in the hollow of the palms while the thumb presses the clay into

shape. E.g.


Pinch Method

ii. Use of Moulds: The moulds for bricks may be made of wood while the ones

for sanitary wares and tiles are metallic. E.g.

A mould

iii. Potter’s wheel method: This is a device containing a flat disc which is

spurned using either an electric motor of manual means. As the clay spins

on the disc the article is shaped using the fingers. E.g.

Potter’s Wheel

2 Firing: Firing of clay helps it to become hardened and durable. The kiln is

usually used for this purpose.

3 Decoration: This is the art of using varnished or ceramic paint to draw patterns

on the surface of any clay product to beautify it.


33

Processing Of Concrete and Cement Blocks

Concrete is processed by the mixture of aggregates, cement, sand and water. The

shape to be casted is first formed using plywood and timber to form a mould.

Sandcrete (cement block) on the other hand is a mixture of sand, cement and

water. Wooden or metallic moulds forms the shape that the block will take.

B. Processing Of Plastics

The general principle in the processing of plastics involves the following:

i. Pre-heating the resin into a molten state.

ii. Forcing the molten plastic into a mould to acquire a desired shape.

Methods of Processing of Plastics

1. Injection Method: In this method, the resin is fed into a heating chamber

through the hopper. A plunger is then used to force the molten plastic into

the required mould. This method can be used for making water bottles. E.g.

Injection Mould

2. Extrusion Moulding: This is the older version of the injection moulding.

Instead of the plunger, a knob with screw is used to force the molten plastic

into the mould. E.g.


Extrusion mould

3. Compression Moulding: This is the method used for processing hollow

pipes like biro cases, water pipes and drainage pipes. This method makes use

of two moulds at a time. E.g.

Compression mould

4. Vacuum Forming: This is the method used in the processing of plastic

cups, buckets and bowls. A vacuum is always created with the cavity of the

mould. As air is sucked out of the cavity, pressure is created on the plastic so

as to take the shape of the mould. E.g.

Vacuum mould


35

5. Calendaring: This is the method used to produce long sheets of plastics like

nylon and polythene products. The plastic runs through a number of rollers.

E.g.

Calendaring process

C.Processing of Rubber

Artificial (synthetic) rubber and natural rubber are processed through the following

stages:

Foremost, the rubber is softened by adding chemicals and mixing it

thoroughly to bring it to a mouldable state.

It is then pre-heated in a chamber into a molten form.

The molten rubber is then forced in to a mould designed to take the shape of

the article desired.

It should be noted that the methods used in the processing of plastics, is also

the same method applied in the processing of rubber.

Application of Rubber

1. Tyres

2. Soles for shoes

3. Foamed rubber products

4. Sports equipment

5. Footwear

6. Engine belts

7. Shock absorbers

8. Conveyor belts


9. Hose

10. Seals

REVIEW QUESTIONS

1. Identify three process involved in the production of plastics,

2. Identify four process involved in the production of rubber

3. Identify three process involved in the production of ceramics.

4. Explain with diagrams the processes involved in the production of the

above mentioned materials.


37

LESSON1.4

PICTORIAL DRAWING

(Isometric Drawing)


1. Define isometric drawing

2. State the angle of projection in isometric drawing

3. Engage effectively in isometric drawing.

4. Define oblique drawing

5. State the axes of oblique drawing

6. Construct oblique blocks

7. Define perspective drawing

8. Engage in both one-point and two-point perspectives

Definition: Isometric drawing is defined as a three- dimensional drawing of solid

objects. It is a pictorial method of drawing. What you see is what you draw. The

three dimensions are the length, width and height.

Isometric Axes

The term isometric axis means the lines formed by the 300 set square and the

vertical line of any given plane or block to be drawn. The lines that slant at 300 is

called the receding lines. The vertical line is also drawn using the side of the

300/60

0 set square. E.g.


Isometric axes

The lines drawn are often referred to as projection lines. Apart from the vertical

lines, all other lines are inclined at 300 slant. It is always better to complete the

drawing in construction line (faint lines) first, check that everything is correct

before outlining the block given.

Steps Involved in Isometric Drawing

1. Drawing the Isometric Axes

After setting your paper on your board and drawing border lines and title

block, follow the steps below:

i. On the lower section of your drawing paper mark a small cross (+).

ii. Using the 300-60

0 set-square, supported on the T-square, draw the first

vertical axis from the intersection of the +.

iii. Turn the set square to the 300 slant with the edge intersecting at the + either

to the right or left and draw the first receding axis.

iv. Rotate the set-square until another edge rest as base on the T-square on the

same intersection and draw the second receding axis.

2. Outlining the Edges: Finally, using the HB pencil with moderate pressure,

thicken the outline of the given block. You may erase the extra projected lines

on your work since they may not be required as part of the given block.

3. Dimensioning: This is the technique of adding the actual size (length, breadth

and height) of any block given. The following steps explains how:

(i). With the aid of the set-square and a little distance from the block drawn,

draw faint projections (the projection lines should not touch the block) as the

block.


39

(ii). Rotating the set square appropriately, draw arrowhead lines to indicate

demarcations on the given block.

For demonstration, see the downloaded Video Titled, “ISOMETRIC DRAWING”.

Oblique Drawing

Definition: This is another form of pictorial drawing of solid objects with one face

upright on the plane of the paper while the other is inclined at 450. E.g.

Types of Oblique Drawing

i. Cavalier Projection: This is a situation where an oblique block is drawn

full length, without alteration or distortion of the original dimension. E.g.

ii. Cabinet Projection: In this method, where the horizontal line is drawn full

size while the 450 slant drawn half size. E.g.


Cabinet Projection

Steps Involved in Oblique Projection

Figure shows Oblique Drawing Steps

NOTE: Unless you are given specific instructions, all oblique drawings should be

carried out at an angle of 450 and dimensions reduced by half. This is very

important in an examination setting.

For demonstration, see the downloaded Video Titled, “OBLIQUE DRAWING”.

Perspective Drawing

Definition: This is a drawing that gives the distant part of an object, like a building

or road. The drawing tapers to a point called the varnishing point (VP), as it

appears to an observer of the object.

This makes the outlook of the distant object smaller than the real size. E.g.


41

One-Point Perspective

Types of Perspective Drawing

i. One-Point Perspective Drawing: In this type of drawing, the projection

lines converge at a particular point known as the varnishing point. e.g.

Like the one shown above.

ii. Two-Point perspective Drawing: This type contains two varnishing points

and the two appear to end at a point in two directions. E.g.

Two-Point Perspective

For demonstration, see the downloaded Video Titled, “ PERSPECTIVE

DRAWING”.


REVIEW QUESTIONS:

1. Draw the block shown below in Isometric projection (show all

dimensions)

2. Draw the block shown below in Cavalier Oblique projection.

3. Draw a One-Point Perspective of the figure below.


43

LESSON-1.5

ORTHOGRAPHIC PROJECTION


1. Define orthographic projection

2. State and explain the angles of projection and

3. Convert isometric drawings to orthographic projection.

Definition:

The word orthographic is coined from the word orthogonal (or perpendicular) and

graphic (or view). As such, orthographic projection can be defined as a two-

dimensional drawing that shows different views of a structure. It contains the

vertical and the horizontal planes as shown below.

Orthographic Planes

Elevations (Views)

In orthographic projection, there are three basic views referred to as elevations.

These elevations are as follows:

(i).The Plan: This is the view of an object as seen or projected from the top.

(ii).Front elevation: This is the view of an object as seen or projected from the


front side of the object or block.

(iii).End (Side) Elevation: This view is sometimes referred to as the auxiliary

vertical plane in some text books. It is the view showing the right or left side of

any object when viewed from the front. E.g.

Angles of Projection

i. First Angle Projection: Where the plan of a structure is positioned below

the quadrant. It is the British system of drawing elevations. E.g.

ii. Third angle projection: This is a condition where the plan of a structure is

positioned above the quadrant while the front view is below the plan.

E.g.


45

First and Third Angle Positioning of Elevations

Steps in Orthographic Projection and Worked Illustrations

(i).Make a sketch of the required views.

(ii).Draw both the vertical and the horizontal axis to intersect midway.

(iii).Determine the placing of the views.

(iv).Begin drawing with either the plan or front views.

(v).From either of the views drawn above, project lines for the other

view.

(vi).Draw the reflector line at 450 .

(vii).Project the horizontal lines from the front elevation.

(viii).Project the plan to meet the reflector line of the 450.

(ix).Take note of hidden details and outline the elevations to complete the

job.

Before you consider any example, I strongly recommend that you go, watch the

Downloaded Video Titled, “ORTHOGRAPHIC PROJECTION”.

Do This


Draw the block shown on page 168 of the J.N. Green text book in orthographic

projection in both 1st and 3

rd angle projections, using arrow X as the front

elevation.

The J.N. Green edition

LESSON-1.6

WOODWORK MACHINES


1. Define woodwork machine.

2. Identify five portable power hand tools

3. Identify four machine tools

4. State the uses of wood working machines

Definition: Woodwork machines are specially designed machines used for wood

operations in furniture work. There are two basic classes of wood working

machines in use. They are:

1.Portable Power Hand Tool Machines(Electrically powered)


47

2.Wood- work machines.

1. Portable Power Hand Tool Machines include the following:

(i).Hand drills: This is an electrically powered tool used for boring holes in wood.

It contains the chuck which turns the drill bit clockwise and anti-clockwise. E.g.

Portable drilling machine

(ii).Belt sander: This machine is used for sanding (smoothening) the surface of

wood. Abrasive is used to coat the rollers in this electrically powered tool. E.g.

Belt sander

(iii).Circular saw: The circular saw is used for cross-cutting timber, for cutting

depth and for forming grooves on timber. It is electrically powered also. It can be

adjusted to any desired position. E.g.


Circular saw

(iv). Saber Saw: This is a flexible saw used for cutting complex shapes like

curves on plywood. Like the curves found on loudspeakers. E.g.

Saber saw

(v).Nailing gun: As the name implies, this machine is used instead of the hammer,

in sticking nails into wood. E.g.

Nailing gun

2.Wood –Work Machines:

The machines covered in this section are usually mounted in engineering

workshops, since they are not portable in nature. There are six different ones to be

considered.

(i).Circular sawing machine: It is used for both cross-cutting and ripping

operations during wood work. E.g.


49

Circular sawing machine

(ii).Band sawing machine: This machine uses the band saw. It is used for cutting

straight lines, circular and irregular curves on timber and plywood. E.g.

(iii).Thicknessing machine: This is the machine used for forming the required

thickness for stool and table legs. E.g.

Thicknessing machine

(iv).Surface planer: The surface planer is designed for planning operations,

especially planks. It can also be adopted for rebating and tenoning jobs. It has a

wide, flat surface for supporting any load laid on it. E.g.


Surface planers

(v). Drill press: This machine has multiple applications. It is primarily used for

drilling operations, for boring holes on wood and metals. It can also be used for

sanding, shaping and mortising. E.g.

Drill press

(vi).Wood lathe: This is the father of all machines. Primarily, it is used for turning

operations to form table legs and lamp stands or stool stands. It is used also for

scraping, sanding, grooving. E.g.

Wood Lathe


51

REVIEW QUESTIONS

1. Define a woodwork machine.

2. Identify at least five portable power hand tools

3. Identify at least four machine tools

4. Explain the uses of wood working machines

LESSON-1.7

SIMPLE WOOD PROJECTS

Woodwork projects demand a lot of organization and planning. This is done so as

to present a professionally finished product.

Stages in Woodwork Project

1. Design Stage: This is the stage where your mind conceives of a concept or

an idea of what type of article you want to produce and how I will look like.

2. Drawing Stage: This is the stage where you draw your concept or

idea. It could be a very simple sketch. It could be the whole article

first, then the views.

3. Fabrication Stage: This stage is a combination of the working

drawing and your cutting list. This list shows the dimension,

quantity and description of the article.

Sample of a Cutting List for a Wooden Tray Project

Part Length Width Thickness Material

Side 2 400 120 18 Opepe

End 2 200 120 6 Opepe

Bottom 1 400 180 8 Plywood


In order to use wood to produce furniture articles, they must be joined together.

These parts are generally referred to as joints in woodwork.

Classes of Wood Joints

Wood joints are grouped into three classes, namely:

1.Box Joints: These are the classes of wood joints that form angle of 900. They

include butt and dovetail joints.

(a).Butt joint: These are joints used in the construction of boxes, window frames,

roofing and cabinet products, door frames, tables and chairs. E.g.

Butt Joints

(b).Dovetail joint: This type of joint is used for making bookshelves drawers for

office tables and for making corner joints. E.g.

Dovetail joints

2. Framing joints: These are joints that are used to form frames or network with

cris-crossing endings. They include housing, halving, mortise and bridle joints. e.g.


53

Half-Lap Joints

(a).Housing and Halving joints: These are joints used for making wardrobe,

chairs, table, cupboard and other articles of this nature.

Cross halving joints

(b).Mortise and Tenon joints: These are the strongest types of joints. There is the

common, haunched and bareface M&T joints. These joints are used for

making door, window frames, tables, chairs and bench legs.

M& T Joints

3.Widening joints: These joints are used for increasing either breath or length of

boards. They include joints like tongue and groove joints, dowell joints.


(a). Tongue and Groove joints: These are joints used as floor and wall tiles in

most British homes. It is mainly used for decoration.

Tongue and Groove Joints

(b). Dowell joint: Dowell joints are usually stronger and are used for cabinets and

dining tables. E.g.

Dowell Joints

Non-Wood Materials in Woodwork Projects

A number of non-wood materials used in woodwork include the following:

Adhesive (gum and glue).

Abrasive (sand paper).

Hinges and locks.

Nails, screws and fittings.

1. Adhesives: These are substances that can bond wooden, leather and other non-

wood materials together. There are three groups of adhesives as shown below.


55

(a).Protein Adhesives: These are natural adhesives derived from various protein

sources. They include scotch glue (animal glue), casein glue made from milk and

blood albumen glue (animal blood).

(b).Synthetic Adhesives: These are adhesives made from organic compounds.

They include thermoplastic glue ( adhesives that can melt under heat) and

thermoset glues( glue that cannot melt under heat).

(c).Contact adhesives: These are the type of adhesives used for dissimilar

materials. Examples of dissimilar materials are wood and leather, paper and leather

or plastic and metal. The types of adhesives in this group include evostik, bostick,

super-glue, araldite, etc.

2.Abrasives:These are papers, cloths and fibers that are coated with hard minerals

like sand, used to smoothen the surface of other materials like rough surfaces of

wood, rusted metals, etc. They are grouped as either as coarse (rough) type,

medium and fine (smooth) type. E.g.

Abrasive

3.Hinges: Hinges are fittings used to hold doors and windows in place. They help

the doors and windows to swing easily. There are different types of hinges in use

depending on the type of work to be done. The common types of hinges are as

follows:

(a).Flat hinges: These are general-purpose hinges that come in different sizes.

They are commonly used for wooden doors, windows and lockers. E.g.


Flat hinges

(b).Tee hinges: These are hinges that look like the letter ‘T’ in shape. They are

used for bigger doors used on shops and garage doors. E.g.

Tee hinges

(c).Butt hinges: These hinges look exactly like the flat hinges. The only difference

is that these hinges are a little bigger than the flat hinges. They are used for both

external and internal doors. E.g.

Butt hinges


57

(d).Lift-off hinges: These types of hinges are used for special types of jobs.

e.g.

Lift-off hinges

4.Locks: Locks are used to secure openings.

i. Wardrobe lock, box lock, and cupboard locks: They are used for cabinets,

boxes and chests. E.g.

Wardrobe lock Box lock Cupboard lock

iii. Mortise lock, cylinder latch lock, rim lock, sliding door lock and the

common padlock: These types of locks are used on doors, especially

room doors. E.g.


Mortise lock cylinder latch lock Rim lock

Sliding door lock Common padlock

5.Nails: Nails are used to fasten wood pieces together. The different types of nails

c include the following:

(a).Round nail: These are nails used for fastening packing cases. E.g.

Round nail

(b).Oval nail: These are nails used in upholstery furniture jobs, like coition chairs.

E.g.

Oval nail

(c).Cut floor brad nail: These are nails used for fastening floor boards. E.g.


59

Cut floor brad nails

(d).Panel pin nails: These are the nails used for cabinet work, picture frame and

any other lighter job. E.g.

Panel pin nails

6.Screws: Screws are also used for fastening wood pieces together, for firmer

result. The following describes the different types of screws:

(a).Counter-sunk screw: This is a general-purpose screw used in all types of

wood work. They come in different sizes. They have a straight slot. E.g.

Counter-sunk screw

(b).Round head screw: It is used to fasten metal handles on wooden materials.

E.g.


Round head screw

(c).Raised head screw: These are screws used in most furniture work like cabinets

and office tables. E.g.

Raised head screw

7.Fittings: Fittings are used as part of the finishing process in furniture. They

include catches, handles and stays. E.g.

Catches Handles Stays

8.Finishes: Finishes are chemicals used on the surfaces of wood work used to

beautify it after sanding and scraping. The different types of finishes include the

following:

(a).Varnish: These are chemicals that give wood a hard, tough layer coating.

There are two types namely, the oil and the spirit vanishes. E.g.


61

Varnish on timber

(b).Lacquer: This is the finish that is commonly used by furniture makers. It gives

furniture a glossy, shiny finish. It adapts to any weather. E.g.

Wood Lacquers in colours

(c).French polish: This finish is used generally to beautify woodwork. It easily

dissolves in thinner or spirit. E.g.

Shades of French polishes

(d).Wax polish: This polish is derived from animal fat, used for beautification of

wood work. There are three types of wax polish namely, animal wax, vegetable

wax and mineral wax. E.g.


Wax polish

(e).Paints: This finish is used to decorate and preserve any wood work. They

include gloss oil, semi-oil, metallic and plastic paints. E.g.

Different shades of furniture paints

(f).Creosote: This type of finish is used as a preservative against fungus and insect

attack. E.g.

Containers of Creosote

REVIEW QUESTIONS

(i).Name five non-wood materials used in woodwork.

(ii).List and explain two types of adhesives, three types of hinges and four

types of nails.

(iii).Name five types of finishes you have learned.


63

LESSON-1.8

INTRODUCTION TO

METALWORK MACHINES


1.define metalwork machines

2.identify and state the different types of metalwork machines

3.state the uses of metalwork machines.

Definition:

Metalwork machines are devices that are driven by electricity to perform different

operations.

The machines used in metalwork operations are generally referred to as metalwork

machines. They are of different types and sizes.

Types of Metalwork Machines

1.Milling machine: This machine is used for cutting gears, grooves slots and to

cut splines in shafts of metal rods. e.g.

Horizontal milling machine


2.Shaper and Planers: The shaper is used to generate flat surfaces while the

planner is used for producing flat surfaces which the milling machine cannot

achieve. E.g.

A Shaping machine

3.Power Sawing machine: This is an electrically powered sawing machine used in

cutting soft metal materials, by using hack-saw blade with coarse tooth. The coarse

blade is used so as to avoid clogging of the teeth by metal chips. E.g.

power sawing machine

4.Pedestal grinder: This machine is used for grinding (sharpening) the cutting

edges of cutting tools. It can also be used to grind scribers, cold chisels and drills.

They are of two types, namely, the floor type and the bench type. E.g.


65

Pedestal grinders

5.Drill press: The drill press is used for boring holes in thick metals. Drill bits are

fitted into its chuck that has different sizes. E.g.

drill press

6.Centre Lathe Machine: As mentioned earlier, the lathe machine is an all-

purpose machine, used for the following operations:

(i).generate cylindrical, flat and conical surfaces;

(ii).cut holes in geometrical shapes;

(iii).cut threads on screws, bolts and nuts;

(iv).reduce the size of geometrical shapes.

(v).used for milling, turning, shaping and planing. E.g.


Centre Lathe

Work-Holding Methods on the Lathe

In metal work involving the use of the lathe machine, work pieces are held firmly

in place through the use of the following tools:

(i).The chuck: The 3-jaw chuck is used to hold triangular and round work pieces

while the 4-jaw chuck is used for holding square-shaped work pieces. E.g.

3-Jaw Chuck 4-Jaw Chuck

(ii).Driving plates: The driving plate is used when a slender work piece is to be

machined and held between two centers. E.g.

A Driving Plate

(iii).Face plates: When a work piece has an awkward or irregular shape, the work

plate is used for turning the work piece. However, if the work piece is to be turned


67

at parallel or right angle to a flat surface, the face plate is applied for turning. E.g.

A Face Plate

Operations on the Lathe Machine

The lathe machine is used to carry out four major operations, namely:

(i).Facing: This the generation of a plane or flat surface by the lathe machine.

(ii).Plain turning: This is the method of producing cylindrical surfaces by the

lathe machine.

(iii).Stepped: This operation is similar to the plain turning operation. In the

stepped operation, a different cutting tool is applied when a different shape is

desired.

(iv).Taper turning: This is the method of reducing the diameter along the length

of any round work piece.

Care of the Lathe Machine

(i).The moving parts of the lathe machine must be oiled or greased regularly.

(ii).Coolant lubricant should be directed at the cutting spot during cutting

operations.

(iii).The work piece must always be held or clamped rigidly before it is turned on

the lathe.

(iv).Appropriate speed must be applied to any of the operations so as to avoid

damage to both work pieces and the lathe machine.


REVIEW QUESTIONS

1. Define metalwork machines

2. State at least two classes of metalwork machines

3. Identify and state the different types of metalwork machines

4. State the uses of metalwork machines.

5. State at least eight parts of a centre lathe machine

6. Explain the following terms:

(a). Facing

(b). Stepped

(c). Taper turning

(d). Plain turning

7. State five ways you may care for a lathe machine.


69

LESSON-1.9

SIMPLE METALWORK PROJECTS


1. Define fabrication

2. State at least five steps involved in fabrication

3. State at least five tools used for metalwork fabrication

4. State at least one use each of the tools mentioned in 3 above

5. Define forging

6. State at least three basic forging tools

7. Identify at least four types of tongs

8. State at least one use of the following:

(a). Hardie (b). Fuller (c). Chisels

9. State the following functions:

(a). Bending (b). Drawing down (c). Twisting (d). Upsetting

10. Define metal finishing

11. Explain the following metal finishing terms:

(a). Buffing (b). Scratching (c). Enamelling (d). Copper finishing

(e). Spot finishing (f). Lacquering (g). Spraying.

12. Explain electroplating in metalwork.

Metalwork project involves the use of metal sheets to fabricate articles.

Fabrication: Fabrication is the use of metal sheets to make different metal articles

for use.

Fabrication Processes

i. Sketching: This is art of drawing the desired article, with dimensions on

paper first.


ii. Measurement: On the metal sheet, the size of the article to be fabricated

must be measured next, using a scriber.

iii. Marking out: At this stage, the scriber is used to mark-out parts of the

article on the metal sheet.

iv. Cutting: A snip is used at this stage to cut through the path marked on the

metal sheet.

v. Filing: To smoothen the rough edges of the cut article, a pedestal grinder or

file can be used to achieve this.

Tools for Metalwork Fabrication

(i).Measuring tool: The basic measuring tools used in metal work include centre

square, steel rule, outside and inside calipers and protractor. These tools are all

used for measuring lengths, widths and angles. E.g.

Measuring tape

(ii).Marking-out tool: The main tool used here is the scriber. This tool is used

together with measuring tools. e.g.

A scriber


71

(iii).Cutting tools: The list in this category, include chisels, snips, bench shears

and hack saw. One must consider the thickness of the metal you are about to cut

before choosing the right cutting tool. E.g.

Cutting tools

(iv).Files: In metal work projects, files are used to remove sharp and rough edges

so as to produce a smooth final finish. E.g.

Files

(v).Drill bits: Drill bits are fitted into the chuck of drilling machines. They are

used to bore holes on metal plates. They come in different types which include

counter sunk, flat, straight-fluted, twist and combination drill bits. E.g.


Drill bi ts

Forging

Definition: Forging is defined as the hammering of hot metal and shaping it into a

required shape. The heating tool is the blacksmith’s hearth.

Basic Forging Tools

1. Blacksmith’s Hearth: This is the heating tool for the metal to be forged. The

fuel can be coal or charcoal while below supplies the air for fanning the hearth.

E.g.

Blacksmith’s hearths

2. Anvil: This is a tool made of cast steel, where the work piece to be forged is

placed for hammering. E.g.


73

3. Tongs: Tongs are used to hold the metal being forged.

Types of Tongs

i. Hollow-bit tong: Used for holding round or hexagonal shaped metals. E.g.

Hollow-bit tong

ii.Open mouth tong: Used for holding square metals. E.g.

Open-mouth Tong

iii.Close mouth tong: Used for holding rectangular or flat metals. E.g.


Close-mouth tong

iv.Square mouth tong: This tong is used to hold irregular, rectangular and square

metals. E.g.

Square mouth tongs

4.Hardie: Used for cutting both hot and cold metals. The hardie is fitted to the top

of the anvil. E.g.

Hot and cold hardies

5.Fuller: Used for forming grooves on metals. There is the top and bottom fuller.

E.g.


75

Fullers

6.Chisel: In forging, the hot chisel is used for cutting hot metals while the cold

chisel is used for cutting cold metals. E.g.

Shape Development

(i).Bending: Most metalwork project involves bending and folding, either

cylindrically or as square-box shape. This changes the shape of the metal. E.g.

Bending a metal sheet

(ii). Drawing down: This is the process of stretching a metal by hammering. E.g.


Drawing down

(iii). Twisting: This is a beautification process in forging operation. E.g.

(iv). Upsetting: This is the process of increasing the thickness of a metal. It is

useful in processing bolt heads. E.g.

Upsetting

Metal Finishing

Metal finishing is the process of beautifying metal surfaces so as to prevent rust

and prolong its economic life.

Types of Metal Finishing

1. Buffing: This is the method of using wheels covered with soft cloth or

leather to polish the surface of metal. E.g.


77

Buffing

2. Lacquering: This is the application of lacquer to metal surface to prevent

corrosion.

3. Enameling: This is the application of corrosion-resistant material, like

plastics, on metal to make the surface glossy and hard. E.g. kerosene stoves.

Enamelling

4. Scratching: This is the use of a thin metal piece and steel brush for cleaning

metal parts thoroughly to be finished. E.g.

Metal brush

5. Painting/Spraying: This is the application of oil paint to metal for coating

purpose. E.g.


Spraying

6. Copper finishing: This is the oxidation of copper surface to form shades of

different colours like purple, red, brown, etc.

Copper finishing

7. Spot Finishing: This is the forming of pressed spots on metal by the use of

ornamental finishing and abrasive powder and oil spread over the metal.

Spot is achieved by placing the metal over a spinning wood on a drill chuck.

E.g.

Spot finishing

8. Electroplating: This is the protective coating of a metal with other metal

such as tin, zinc or chromium so as to prevent corrosion.

Electroplating


79

REVIEW QUESTIONS

1. Define fabrication

2. State at least five steps involved in fabrication

3. State at least five tools used for metalwork fabrication

4. State at least one use each of the tools mentioned in 3 above

5. Define forging

6. State at least three basic forging tools

7. Identify at least four types of tongs

8. State at least one use of the following:

(a). Hardie (b). Fuller (c). Chisels

9. State the following functions:

(a). Bending (b). Drawing down (c). Twisting (d). Upsetting

10. Define metal finishing

11. Explain the following metal finishing terms:

(a). Buffing (b). Scratching (c). Enamelling (d). Copper finishing

(e). Spot finishing (f). Lacquering (g). Spraying.

12. Explain electroplating in metalwork.


LESSON-1.10

METAL JOINING


1. Define metal joinery

2. List four methods of joining metals

3. Define the following:

i. soldering

ii. welding

iii. riveting

iv. brazing

v. mechanical fasteners

4. State the function of flux

5. List five soldering tools.

Definition: Metal joining is defined as the process of sticking metals

together with the use of fasteners, either permanently or temporarily.

Methods of Joining Metals

1. Soldering

Soldering is a method of joining metal surfaces together by means of an alloy

metal called solder (flexible lead wire).

Types of Soldering.

(i).Soft Soldering: This type of soldering takes place in temperatures between 1880

c - 2500c. The soft solder used during this soldering operation is an alloy of tin and

lead. It is used on radios and television.


81

(ii).Hard (Silver) Soldering: Silver soldering makes use of solder which melts

above red heat. The solder is an alloy of copper and zinc. It is used on fridges and

air-conditioners.

Tools and Materials Required for Soldering

Both the tools and materials used during soldering operations are grouped together.

They include the following:

(i). Soldering bit: Soldering bit is used to apply heat and soft solder to a large

surface area of metal parts. Such as the ones used in panel beating. E.g.

Soldering bits

(ii).Soldering iron: Soldering iron is used to apply heat and soft solder to smaller

spots and joints in electrical and electronic circuits. (radio and television). E.g.

Soldering iron

(iii).Solder: Solder is an alloy whose melting point is lower than that of the metals

to be joined through this method. E.g.


|

Solder

(iv).Flux: These are chemical reagents used for clearing and removing oxides from

surfaces to be joined. This is to prevent oxides from forming on such surfaces so as

to achieve a smooth finish. Some flux used are olive oil, candle grease and resin.

E.g.

Soldering flux container

(v).Heat source: Heat source during soldering may be electrically applied or

manually applied. For instance some use charcoal heat source to heat soldering bit.

However, electrically heated sources are common these days.

2. Brazing Brazing is the joining of metals using an alloy of copper plus zinc (brass). Brazing

is a type of hard soldering, that ranges from 8500 C and 950

0 C.

Brazing is used for making stronger joints and a red heat is usually needed to melt

them.


83

Brazing operation in progress

Flux for Brazing: The soldering flux for brazing is referred to as borax. As stated

earlier, flux is a cleaning agent that removes oxide from joints. Borax, in the form

of white powder is mostly used during brazing.

Heat Source: In brazing, the heating tool is the brazing hearth. E.g.

Brazing hearth

3.Welding

Definition: Welding is the process of melting a metal work piece and a filler to

form a pool of molten strong jo int. Welding is permanent fastener for metals.

Types of Welding

i. Arc Welding: This is the process of maintaining an electric arc between an

electrode and a base material to melt metals at a welding point. The

electrode may be consumable or non-consumable. E.g.


Arc welding in progress

ii. Gas (Oxyacetylene) Welding: This process involves the use of combustion

of acetylene in oxygen to produce a welding flame of about 31000C. It is

widely used for welding pipes and tubes and for cutting metals or panel

beating in vehicles. E.g.

Gas welding in progress

4.Mechanical Fasteners: These are often referred to as temporary fasteners since

parts can be easily separated. Mechanical fasteners include screw and nut, bolt and

nut, taper pin, stud and split pin. E.g.

Mechanical fasteners

5.Riveting: This is a permanent fastener in metalwork. The rivet has a head and a

buck-tail. For the rivet to be installed, the head is positioned in a drilled hole and


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the tail is made to deform by hammering, so that it spreads to twice its original

shaft diameter. E.g.

Rivets

REVIEW QUESTIONS

1. Define metal joinery

2. List four methods of joining metals

3. Define the following:

i. soldering

ii. welding

iii. riveting

iv. brazing

v. mechanical fasteners

4. State the function of flux

5. List five soldering tools.

LESSONS 1.11/12.

SEE PAGE 170 FOR REVISION QUESTIONS

PART 2


LESSON-2.1

MECHANICAL ENERGY

TRANSMISSION


1. State what friction is

2. State the features of friction

3. State at least five causes of friction

4. State at least three laws of friction.

Introduction

Within a mechanical device, energy is transmitted from one point to another. In

this topic you will learn the following:

1. What friction is.

2. Features of friction

3. Causes of friction

4. The laws of friction.

Definition: Friction can be defined as the force that opposes the motion between

two surfaces in contact.

Features of Friction


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(i). That friction is an opposing force.

(ii). That friction exists between two plane surfaces in contact.

(ii). That friction has certain effects.

Causes of Friction

1. Deformation: Surfaces that deform increases resistance to motion. For

instance, a rugged floor or coition chair may sink slightly and reduce

motion.

2. Rough Surfaces: Friction occurs when rough surfaces come in contact.

Examples include bicycle and car tyres.

3. Molecular adhesion: This occurs when two surfaces in contact stick

together, thereby reducing motion. Example of this is rubber and plastics.

Laws of Friction

a. Friction does not depend on the speed of rubbing.

b. Friction depends on the magnitude of the pressure between the rubbing

surfaces in contact.

c. Friction does not depend on the area of the surfaces in contact.

d. Friction depends on the nature of the surfaces in contact.

REVIEW QUESTIONS

1. What friction is.

2. List three features of friction

3. State four causes of friction

4. State three laws of friction.


LESSON-2.2

MECHANICAL TRANSMISSION

SYSTEM (EFFECTS OF FRICTION)


1. State six effects of friction

2. State five application of friction

3. Explain four advantages of friction

4. State four disadvantages of friction

5. State four ways you can reduce friction.

Effects of Friction

a. With friction, one can hold a pen to write.

b. Friction makes it possible for machine parts to move.

c. Friction produces heat.

d. Friction supports grinding.

e. Friction reduces efficiency in machines.

f. Friction aids walking and running.

g. Friction makes it possible for brakes to function effectively.

h. Friction results in wear and tear of moving parts.

Application of Friction

All around us, we see the application of friction. Examples include:

i. The design of brakes in engineering systems.


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ii. In the design of belt and chain drives.

iii. In the design of clutches in vehicles.

iv. In the design of pepper grinding machine.

v. The design of grooves in a pulley system.

Advantages of Friction

i. Friction makes it possible for humans to walk without slipping.

ii. Friction makes possible for us to sharpen knives cutters and any other grinding

tools.

iii. With friction the transmission of motion is possible in drives like tyres and

machine parts.

iv. Friction makes it possible for brakes to function properly.

Disadvantages of Friction

i. Friction results in the loss of energy by machines, as such no machine has 100%

efficiency.

ii. Friction causes wear and tear in machines, as it reduces the size of materials

gradually.

iii. Friction causes excessive heat in machines, which must be controlled.

Methods of Reducing Friction

a. Lubrication: This is the process of applying oil or grease on surfaces which

makes surfaces in contact to slide against each other. E.g.

Two surface lubricated

b. Use of Bearings: Ball bearings or metals made of different materials

reduces friction since the surfaces in contact slide on each other thereby

reducing friction. E.g.


Bearings

c. Use of Rollers: Using cylindrical cans or pipes as rollers placed under a

loaded crate will reduce the effort required to push such a crate if rollers

were not placed under it. e.g.

Rolling an object on rollers

d. Smoothening of Surfaces: The nature of the surfaces in contact matters

when it comes to friction. However, if you want to reduce friction, then

bring two smooth surfaces in contact. Example in include polished glass or

tiled floor. E.g.

Smooth surfaces

e. Streamlining of Body Shapes: Technology has made it possible for

engineers to produce streamlined moving objects. Such objects reduce drag,

since they possess a curved shape. Examples include airplanes, submarines

and sport cars. e.g.


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Streamlined sports car

REVIEW QUESTIONS

1. State six effects of friction

2. State five application of friction

3. Explain four advantages of friction

4. State four disadvantages of friction

5. State four ways of reducing friction.


TOPIC-2.3


SYSTEM

DRIVE MECHANISM (gears and chain drives)

OBJECTIVE(S): At the end of this lesson, the student should be able to:

1. Define belt drive

2. List five machines that make use of belt

3. List two types of belts

4. State at least three advantages of belt drives

5. State at least five applications of chain drives

6. State at least four advantages of chain drives

7. State at least three disadvantages of chain drives

8. Carry out simple calculations involving gears

Belt Drives

Belt drives are simple mechanical devices used for transmitting motion from one

pulley to the other. Belt drives are an arrangement of pulleys which are either

connected to flat or vee-belts.


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Types of Belt Drives

a. Vee Belt and Pulley e.g.

b. Flat Belt Pulley e.g.

c.Variable speed pulley with vee- belts. E.g.

variable speed vee belt or toothed belt.

These three groups of belts can be used to:

Increases or reduces speed from a driver to a driven shaft.

Transmit power over a longer distance between shafts.

Change the direction of motion of both pulleys.

Application of Belt Drives

Belt drives can be used in the following areas:

i. Pepper grinders.

ii. Cassette and video or DVD tape players.

iii. Refrigerating and air-conditioning systems.

iv. Vehicle engines, where motion is transmitted to rotate radiator fan or drive the


alternator.

v. In an alternating current generator, where motion is transmitted from the petrol

engine to the alternator through a belt drive.

vi. The sewing machine-reciprocating rotary motion.

Advantages of Belt Drives

i. Belt drives need less or no maintenance since it requires no lubrication.

ii. Belt drives can be used to transmit motion over a long distance.

iii. Belt drives can be used to transmit power to shafts inclined at an angle

different from the driven shaft.

Disadvantages of Belt Drives

i. Since energy is lost to friction, the transmission of power in belt drives is not

too efficient, in fact no machine is 100% efficient due to heat.

ii. In belt drives, the belt can get worn-out with time and can break suddenly.

Chain Drives

This is an arrangement of a chain connected across two sprocket gears. You can

see the application of a chain drive in:

i. A bicycle

ii. Motorcycle

iii. Forklift, etc.

Chain and gear

Advantages of Chain Drives

i. Chain drives can be used between shafts that are at a great distance apart.

ii. Chain drives transmit power more efficiently because it has less friction.


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iii. Chain drives do not break so easily like belts.

iv. Chain drives, once greased takes time to dry up. This means less

maintenance .

Disadvantages of Chain Drives

i. Chain drives are limited in their use for distances less than one metre.

ii. Chain drives are not easily reversible.

Gears

Gears are toothed wheels used to transmit motion from one shaft to another, to

change speed and direction in machines. They can be made of plastics or metals.

E.g.

Meshing gears

Types of Gears

i. Wheel gears: These are gears that are used when shafts are arranged in

parallel. E.g.


Meshed Wheel gears

ii. Bevel gears: These are gears used where shafts are inclined at 900 to each

other. E.g.

Bevel gear

iii. Worm gears: Where axis of rotation is inclined at 900

the worm gear is

used. E.g.

Worm gear

iv. Sprocket gears: These are the types of gears used on bicycles and

motorcycles. E.g.

Sprocket gears

Applications of Gears

Can be applied in the following mechanical devices:


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i. Wood and metal work machines-lathes

ii. Used on cranes.

iii. Mechanical clocks.

iv. Bicycle and motorcycles.

v. Hoists.

vi. Cars and automobiles.

Uses of Gears

a. Gear is used for transmitting power.

b. Gear can be used to change the direction of travel by transmitting of speed

at 900 with the use of bevel gear.

c. Gear can be used to change speed, either to increase or decrease the speed.

d. Back movement with the selection of bevel gear is possible in most engines.

Calculations Involving gear Drives

When two or more gears are combined, a drive is obtained. In such an

arrangement, one of the gears is referred to as the driver gear, while the other is

referred to as the driven gear.

Driving gear: This is the gear that transmits speed to the other gear.

Driven gear: This is the gear that receives the force of the speed from the driver

gear.

Meshing of gears: This simply means the engagement of the teeth of the gears

(i.e. the teeth enter into each other). E.g.

Meshing gears

Gear ratio: Gear ratio is the relationship between two gears in which it shows how

much larger the speed of one gear is to the other.


To carry out calculations involving gears, let use appropriate parameters to refer to

them.

Driver Gear Number of Teeth = Nd

Speed of Rotation for Driver Gear = Sd (revolution/sec)

Driven Gear Number of Teeth = ND

Speed of Rotation for Driven Gear = SD (rev/sec)

Therefore, Gear Ratio (GR) = Nd

ND

NOTE: It is the gear ratio (GR ), that determines the speed of the Driven Gear.

As such, Speed of the Driven Gear is SD = GR x Sd

This implies that Speed Ratio, GR = SD

Sd (I only cross multiplied. I guess you

understand)

This means that Speed Ratio(SD) = Gear ratio(GR). (The two means the same

thing).

Now, let us use an example to drive home the point more clearly:

EXAMPLE

A bicycle has 40 teeth in its driver gear at the pedal of the bicycle which turns

at a speed of 1000rev/min. If the driven gear at the rear of the bicycle has 80

teeth, calculate the speed of the driven gear.

SOLUTON

Speed of Driver Gear, Sd = 1000rev/min

Number of teeth in Driver Gear, Nd = 40

Number of teeth in Driven Gear, ND = 80

Speed of revolution of Driven Gear = ?

Recall that SD = GR x Sd

But GR = Nd

ND


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= 40 / 80

= 0.5 or 1:2.

Since Sd = 1000rev/min

Therefore, 0.5 x 1000

= 500rev/min.

Example 2.

A forklift consisting of two gears in a mesh have a speed ratio of 2. If the

driven gear rotates at 300 rev/min and has 30 teeth, determine:

i. The gear ratio

ii. The speed of the driver gear

iii. The number of teeth in the driver gear.

SOLUTION

Given that: GR (speed ratio) = 2

SD = 300 rev/min.

ND = 30 teeth

Sd = ?

Nd = ?

Recall that, Speed Ratio = Gear Ratio,

therefore, (i). The gear ratio = 2

(ii). The speed of the driver gear

GR = SD/Sd

Therefore, Sd = SD/GR

= 300/2

= 150 rev/min.

(iii). The number of teeth in the driver gear

GR = Nd/ ND

Therefore, Nd = GR x ND

= 2 x 30

= 60 teeth.


REVIEW QUESTIONS

1. Define belt drive

2. List five machines that make use of belt

3. List two types of belts

4. State at least three advantages of belt drives

5. State at least five applications of chain drives

6. State at least four advantages of chain drives

7. State at least three disadvantages of chain drives

LESSON-2.4

MECHANICAL

TRANSMISSION SYSTEM

(Motion in Engineering System)


1. Define motion

2. State at least two types of motion

3. State the function of a clutch in a vehicle

4. State at least four types of car engines

5. Explain how car engines function

6. State the function of a brake in a machine

7. State at least five machines that can convert rotary motion to linear motion.

Definition

Motion can be defined as the movement of a body (object) from one point to

another with the application of force.


101

Types of Motion

At this level, the two types of motion to be considered are Linear Motion and

Rotary Motion.

Linear Motion: This is the motion of a body moving in a straight line. For

instance, a push-pull link mechanism is a simple machine that operates with linear

motion. E.g.

push-pull link mechanism

Rotary Motion: This is motion of a body moving in a circular form. Examples of

circular motion is the rotation of a fan, vehicle tyres, the handle of the clock, etc.

e.g.

A rotary drive mechanism

Transmission of Motion


For any engine to function, motion must be transmitted from one part of the engine

to other parts. For instance, in a car, motion is often transmitted from the car

engine to the wheels. This is possible because of the motion transmission system in

the car.

The transmission system in a car includes the gearbox and the clutch.

Function of the Clutch: The function of the clutch is to disconnect two shafts

running at different speeds, that is, the engine crankshaft and the gearbox shaft.

The clutch system

Types of Car Engines

1.Front- Engine Rear-Wheel Drive: This is an engine that consists of a clutch, a

gear box, a propeller shaft and a rear axle. Most cars in Nigeria operate with this

type of engine. E.g.

2. Front-Engine Front Wheel Drive: In this type of engine, every other parts

mentioned in 1 above is present except for the propeller shaft. Transmission is

directly from the gearbox to the rotating wheels. E.g.


103

3. Rear-Engine Rear-Wheel Drive: In this type of engine, there is no propeller

shaft also. The clutch, engine and gearbox are all engineered at the back of the car.

Example is Volkswagen cars. E.g.

Rear-Engine Rear-Wheel Drive

4. Front-Engine 4-Wheel Drive: This is a more recent technological

advancement in the engineering of cars. There is no propeller shaft and most

times no mechanical gearbox. The gear system is a hydraulic system. This

car contains the brake and the accelerator only, with all four wheels

connected to the gear box. e.g.

Mechanical Gear System and Hydraulic Gear System.

Control of Rotary Motion-Brakes

Brakes are meant to control motion. Kinetic energy in a moving object is absorbed


by the brake. This produces heat on the brake as kinetic energy is converted into

potential energy. As the brake absorbs heat, the vehicle slows down until it finally

comes to a stop.

How Brakes Work

There are different types of brakes. However, the principle of how the brake works

is the use of friction. If the brake in a car or bicycle is pressed against the rotating

drum or disc or wheel, the resulting friction between the pad and the drum or

wheel slows down the rotating wheels, until they eventually come to a stop. E.g.

Bicycle brake Disc Brake

Conversion of Rotary Motion to Linear Motion

In some machines, it is necessary for a change from one form of motion to another

along it’s line of operation. For instance, a sewing machine will need to convert

linear motion from the moving pedal to rotary motion at the wheel and finally to

linear motion again at the needle. E.g.

A Sewing machine

The piston-crank mechanism of a car engine is another example of converting

rotary motion at one point of an engine to rotary motion at another point of the

same engine. E.g.


105

Piston-Crank Mechanism in a vehicle engine

Other examples of machines involved in converting one form of energy to another

are; Screw jack, Rack and piston steering system, Crankshaft and cylinder,

Metalwork table vice, Woodworker’s vice, Pipe vice, G-clamp, etc.

G-clamp Steering system Pipe vice

REVIEW QUESTION

1. Define motion

2. State at least two types of motion

3. State the function of a clutch in a vehicle

4. State at least four types of car engines

5. Explain how car engines function

6. State the function of a brake in a machine

7. State at least five machines that can convert rotary motion to linear motion.


LESSON-2.5


SYSTEM (AIR FLOW, PNEUMATICS AND HYDRAULIC)


1. Define air flow

2. Identify at least 3 ways of generating air flow

3. Name two types of air flow

4. Define hydraulic

5. Identify four hydraulic devices

6. Define pneumatics

7. Identify four pneumatic devices.

Definition: Airflow can be defined as the continuous and steady movement of air

in a particular direction or at random movement.

Generation of Air: Air can be generated in various ways. Some of these ways

include:

i. Fan

ii. Mouth

iii. Air pump

iv. Bellow

Mechanical Properties Of Air

The mechanical properties of air are weight, atmospheric pressure and the

relationship between pressure, temperature and speed.


107

Weight: That air weighs something can be experimented with an empty balloon.

If filled with air, the balloons original weight increases.

Again, since cold air has weight more than hot air, it is found useful in hot-air-

balloon, in which the heavier air, which is below, pushes up the hot-air balloon.

Atmospheric Pressure: This is the same thing as air pressure. This pressure is

defined as the force per unit area, written mathematically as P = F/A. e.g.

siphoning, etc.

This is found useful in vacuum cleaner, that sucks in dust particles on the rug and

store in the dust bag.

The instrument used for measuring air pressure is called barometer.

Sound: Air produces sound as it passes through a narrow path, as it is found in

trumpets and flutes.

Others: Other application of airflow is in air crafts. The high speed that

discharges at the rear of the engine and thus pushes the aircraft forward.

Again, since air pressure decreases with increase in height, aircrafts are able to

travel at a higher altitude.

Extremes of Airflow

There are two extremes of airflow, namely:

Laminar Air Flow: This is a steady flow of air . It is also called streamline flow.

Turbulent Flow: This is the unsteady speed flow of air. Sometimes it is a forced

air flow. E.g.


Pneumatics Devices

Pneumatics is a device that makes use of compressed air to do useful work. Such

devices make use of cylinders to produce force or linear motion at changing

speeds. Generally, both pneumatics and hydraulic devices are used for the

following purposes.

For pushing

For pulling and

For lifting

Pneumatic devices include the following:

Hand Pump: These are of different types, they are used to inflate tyres, balloons,

balls etc. the hand pump has a plunger which sucks in and pushes out air at the

barrel cylinder.

Hand pump

Compressor Machine: This is used by vulcanizers, while the modified one is used

as a spray machine on several products. E.g.


109

Compressor machine

Hydraulic Devices

Hydraulics are devices that make use of fluids or liquids to push, pull and lift

materials in a machine. They include the following:

Hydraulic Jack: This jack has two main parts – the handle and the lever which is

connected by two pistons which raises the lever that raises the load (car). E.g.

External and Internal Structure of a Hydraulic Jack

Suction and Double Acting Pump: These are manually operated pumps used for

lifting liquids and gases from reservoirs. e.g.


Double Acting pump

Garden Sprinkler: The sprinkler is used in water gardens. It has jets which issues

out water at a given speed about an axis. e.g.

Water sprinklers.

Water wheel: This wheel can be used to create mechanical energy in grinding,

milling and electric power machines. E.g.

Water wheel

Others: Other devices that make use of hydraulic system include-(a) Reaction

turbine (at dams) and (b) Brakes – used in cars to control motion, etc.


111

REVIEW QUESTIONS

1. What is pneumatics?

2. What is hydraulic?

3. Name 2 devices that use pneumatics

4. Name 4 devices that make use of hydraulic

5. Using the sketches shown on your text book sketch the following

6. Hand pump

7. Suction and double acting pump

8. Garden sprinkler

9. Water wheel


LESSON-2.6

SIMPLE ELECTRICAL WIRING


1. State two wiring systems.

2. List at least six appliances utilizing electricity.

3. Name at least two types of electricity consumers.

4. Identify the insulation colour of Live, Neutral and Earth cables.

5. Define live, neutral and earth wires.

6. List five household wiring accessories.

7. Explain at least two methods of house wiring

Introduction

Electrical wiring can be carried out in buildings, vehicles, machine plants,

appliances and equipments. In this topic, we will be considering electrical

installation in houses.

Types of Consumers

1. Domestic consumers

2. Industrial consumers

Utilization of Electricity

Utilization of electricity simply means making use of electricity. The various types

of appliances that utilizes electricity at homes, offices and industries include the

following:

i. Air-conditioner

ii. Ceiling/Standing fan

iii. Television

iv. Refrigerator

v. Electric pressing iron, etc.


113

Household Wiring

Household wiring commonly involves three types of wires:

i. the live wire- symbol is (L)

ii. the neutral wire –symbol is (N)

iii. the earth wire- symbol is (E).

e.g.

Wire symbols

House Wiring Systems

The name and type of wiring system depends on the mechanical protection adopted

for the wiring. There are two main types of wiring systems:

(a). Surface wiring: In this system the cables are laid on the surface of the walls.

(b). Conduit wiring: It is a system where the cables are inserted into the metal or

P.V.C. (poly vinyl chloride) tube, within the wall.

Parallel Wiring of Household Appliances

Wiring installation in households that include lamps and other household

appliances is done in parallel connection.

As such, each of the appliances is having the same voltage and each acquires the

full main potential difference of 220 volts. This system makes it possible that if an

appliance is damaged or faulty, it does not affect the supply of electricity to other

appliances. E.g. of closed circuit in parallel connections.

Series Wiring of Household Appliances


In connecting electrical lamps and appliances in series, this is made possible when

a number of lamps are connected in rows controlled by a single switch. Examples

include stage lighting or in hospital wards, lamps are connected in this way for

easy control. E.g. of closed circuit connected in series. E.g.

Earthling Appliances

Appliances are earthed for safety precaution. Earthling is done when the metal

casings (covers) of all electrical appliances should be connected to earth by earth

cable, E.

If appliances are not connected, a 220V may pass through the body of a person

touching the appliance by accident into the earth. E.g.

Earthed sockets

Safety Devices in House Wiring

i. Fuse: This is a device that contains a short length of wire which melts and

breaks the current if the current exceeds 220 volts. E.g.

Fuses


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ii. Circuit breaker (Switches): These are special switches used to make or

break normal current flow if it exceeds the determined safe value. E.g.

Circuit breakers

Wiring Tools and Materials

Tools: The tools include the following:

i. Pliers and Cutters: Pliers are used as gripping and pulling tools why the

long-nose type is used for preparing the tips of cables before joining them

in the circuit.

The cutter is used to strip the cable of its P.V.C. sheath. E.g.

Cutter pliers curved pliers

ii. Screw driver: This tool is used to drive out and in screws to a material. E.g.

Cross-Section of Screw drivers


iii. Hammer and Plug: These tools are used to bore holes for pegging on a

wall. Plugs hold clips firmly to the wall. E.g.

Hammer Plugs

iv. Spirit level: This tool is used to mark vertical lines on the wall before

boring and pegging. E.g.

Spirit level

Material for Wiring:

They include the following:

i. Clips and Nails: Clips and nails are used to hold cables firmly to the wall. A

type of nail is used on pegs while others are used on the wall directly.

E.g.

Nails

ii. Wooden blocks: These are wooden blocks of different sizes to mount

accessories like switches, ceiling roses, sockets and regulators,

especially in surface wiring. E.g.


117

iii. Cables: Cables are made in different sizes. In Nigeria, the 1mm, two-core

cable is used for lighting connections why the 1.5mm2, three-core cable is

used for socket connections. e.g.

Different shades of electrical cables

Accessories for Wiring Installation

Accessories are fittings used for connecting appliances to circuits. They include the

following:

i. Lamp Holders

ii. Ceiling Roses

iii. Switches (tumbler type)

iv. Socket Outlets and Plugs

v. Ceiling Switches

vi. Joint Boxes

vii. Lamp Holder Adaptors

viii. Batten Lamp holder, etc.

Batten Lamp Holder Lamp Holders Joint box Ceiling rose

Tumbler s witch 3-pin Plug wall sockets


Wiring Lighting Circuits

There are different ways of connecting lamps and switches in households. Two

ways will be illustrated below:

Case 1: Lights connected in series. E.g.

Case 2: One lighting point controlled by a one -way switch. E.g.

Case 3: One lighting point controlled by a single two-way switch. E.g.

Wiring Socket Circuit

Socket circuits are connected differently from lighting circuits. There are two ways

of wiring sockets.

a. Ring Circuit wiring

b. Radial Circuit wiring

In both cases, a three core single cable of 1.5mm2 or 2.5mm

2 is used. In this cable

an earth continuity conductor is added to serve as protection against leakage

current. E.g.


119

Ring Circuit Radial Circuit

Earth leakage current produces shocks where there is no earthling. This explains

why people receive shocks from the metallic cases of appliances that are faulty.

Safety Requirements in Electrical Wiring

i. Switches for bathroom should be installed outside the bathroom.

ii. Always switch off circuits before working on them.

iii. Never use your teeth to strip insulations from cables.

iv. Current-carrying conductors must never be left exposed. Use cello tapes to

cover up exposed joints.

v. When working on live circuits, always use well-insulated tools.

vi. Use appropriate sizes of and ratings of accessories in all installations.

vii. All switches must be connected on live conductor.

REVIEW QUESTIONS

1. State two wiring systems.

2. List at least six appliances utilizing electricity.

3. Name at least two types of electricity consumers.

4. Identify the insulation colour of Live, Neutral and Earth cables.

5. Define live, neutral and earth wires.

6. List five household wiring accessories.

7. Explain at least two methods of house wiring


LESSON-2.7

BUILDING CONSTRUCTION

(FOUNDATION)


1. Define foundation

2. Name at least four types of foundation

3. Identify at least four types of foundation

4. Define at least ten building terminologies.

Definition: This is the lower part of the building that transfers the load of the

building to the soil below without cracking.

Types of Foundation

(i). Strip Foundation: This is the type of foundation made of a continuous strip of

concrete under the wall. For instance, the type used for gutters, fences and small

houses. Concrete is poured evenly on the dug trench before blocks is set on it. E.g.

Strip foundation

(ii). Raft Foundation: This is the type of foundation where the concrete base

expands to cover the entire area under the building. It is suitable for swampy areas.

E.g.


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Raft foundation

(iii).Pad Foundation: This is a reinforced concrete built under columns (or

pillars), carrying the building. Used for bridges or buildings with parking space

under them. E.g.

Pad foundations

(iv). Pile Foundation: This is the type of foundation used for sky scrapers, high-

rise buildings and oil rig platforms. Piles are driven far into the sub-soil to reach

much firmer soil below. E.g.

Pile foundations


(v). Stepped Foundation: This type of foundation is constructed where the land

slopes. It consist of a number of modified strip foundations, stepped at required

intervals. Used especially where the soil is hard. E.g.

Stepped foundation

Understanding Building Terminologies

(i) Foundation: This is the lower part of the building that transfers the load of the

building to the soil below without cracking.

(ii) Architect: This is the professional that draws the building plan(blueprint).

(iii) Quantity surveyor: This is a professional that quantifies the amount of money,

material, labour and workmanship that could finish a particular project or

building.

(iv) Builder: This is the engineer that erects the building according to plan of

the building.

(v) Statutory personnel: This is a government official who makes sure that any

building meets local, state or national standard. If it does not meet the

standard, such buildings are usually demolished.

(vi) Structural engineers: This is a professional that determines and specifies

the strength and types of bui lding materials like cement ratio, number of steel,

etc, for any construction.

(vii) Landscaping: This is the process of making the surrounding of a building

more beautiful by planting trees and flowers and the general topography of

the land. E.g.

Landscaping

(viii) Timbering: This is the practice of using timber to support the vertical sides of

a trench, so as to avoid collapse. E.g.


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Timbering

(ix) Foundation footing: This is the wide base that carries the walls, pillars or

columns of any building. E.g.

(x) Excavation: This is the digging up of earth to a required dept, width and length.

This can be done both manually and mechanically.

(xi) Soil: Soil can be defined as any loose material deposit, such as gravel, sand,

clay or the mixture of all these. There are two types of soils namely, cohesive

and non-cohesive.

(a). Cohesive soil: This is the type of soil that is sticky and closely bonded

together. Example of such soil is mud and clay soil. They are good for

foundations if compacted. E.g.

Cohesive soil

(b).Non-cohesive soil: This type of soil is loose in nature. It includes sharp

sand or loamy soil and gravel. It is the most suitable for foundations since

they have good bearing values. E.g.


Non-cohesive soil

(xii) DPC: The acronym DPC means damp proof course. This is the layer that

prevents the penetration of moisture or water into the building from

underground. Materials that can be used for DPC include waterproof,

polythene and mackintosh. E.g.

DPC in sky blue

(xiii) Lintel: This is the material put over an opening in a wall to enable the wall to

continue above the opening. E.g.

Lintel

(xiv) Rendering: This is the method of spraying mortar or concrete on the surface

of wall, such that the wall then looks coarse (rough). E.g.

Rendered walls

(xv) Bonding: This is the type of arrangement used when laying blocks to ensure

that no vertical joints occurs. E.g.


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Bonding in progress

(xvi) Slab: This is a horizontal part of a bui lding, made from concrete and

supported by columns or walls. E.g.

Slab

(xvii) Batching: This is the process of measuring concrete either by volume or

mass.

(xviii) Curing: This is the process of maintaining a satisfactory moisture condition

for a freshly placed concrete. E.g.

Curing in progress

REVIEW QUESTIONS

1. Define foundation

2. Name at least four types of foundation

3. Identify at least four types of foundation

4. Define the following building terminologies.

(i). DPC, (i)i. Landscape, (iii). Architect, (iv). Lintel

(v). Cohesive soil, (vi). Batching, (vii). Curing, (viii). Excavation

(ix). Slab, (x). Bonding.


LESSON 2.8

BUILDING CONSTRUCTION (WALLS AND FLOORS)


1. Define a wall.

2. List four functions of a wall.

3. List at least five types of walls.

4. State different types of mortar.

5. List at least eight materials used for making wall.

Definition of wall

Wall is a part of a building on the foundation built to support the roof.

Functions of wall

a. To provide a space or compartment for living or for working.

b. Wall resists harsh weather, particularly moisture and cold.

c. To oppose the passage of noise.

d. Wall provides security for structural loads kept within it.

e. To support the load of the building.

f. To enclose and protect the building.

Types of Walls

1. Portable walls: These are cubicle walls that are used to take a large open space

and dividing it into smaller rooms. Examples include schools and hotels.

2.Separation walls: These are walls designed to separate one population from

another. For example, a wall that separates a country that splits into two.

3. Partition walls: These are internal, non-load bearing walls, built for the purpose

of dividing rooms. They can be constructed from glass, roof metals, timber or

plywood.

4. Boundary walls: These are boundary-marking walls on properties, like fences.


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5. Shared walls: This is a wall shared by neighbours, where no one can alter the

common wall. This wall can separate apartments and hotel rooms.

6. Others: Other types of walls, depending on their functions and materials

include:

i. Traditional walls-built from clay and sand.

ii. Timber walls-built with wood.

iii. Cavity walls.

iv. Retaining walls.

v. Stone walls- built from stones or mason.

vi. Brick walls- built from bricks.

Materials for Making Walls

i. Metal-this may be normal flat metal or corrugated roofing metal.

ii. Timber-this may be manufactured boards like plywood.

iii. Blocks-example is sandcrete cement blocks.

iv. Glass-the glass in this regard is set in metal or wood frames or aluminium

frames.

v. Bricks-most brick walls are designed for decorations.

vi. Synthetic materials-these are walls made of plastics from fibre glass.

vii. Stone-this wall is best for building reservoirs, with the aid of mortar.

viii. Leaves and Grass- common for building huts.

ix. Tree trunks and branches- these are usually stuck to the ground and made

to close together.

Yes, the materials for making walls may be many, but for domestic and industrial

buildings blocks are the most popular material in use. As such, how is block wall

bonded?

Materials for Binding Block Walls or Bricks

Mortar is the best choice for binding bricks and blocks. Mortar is the mixture of

cement, little sand and water. It must be weaker than the brick or block, so that if it

cracks, it can be filled back instead of the brick cracking.

Types of Mortar


i. Lime mortar: This is a weaker mortar used with a softer brick. This mortar

is composed of hydrated lime and sand.

ii. Cement mortar: Where damp is to be prevented this type of mortar is used.

It is stronger than the lime mortar. It is composed of cement and sand.

iii. Ganged mortar: This mortar is composed of cement, hydrated lime and

sand. Its strength is between lime mortar and cement mortar. It spreads

easily than cement mortar.

Bonding

Bonding (tying) is the arrangement of bricks or blocks such that the vertical

alignment of joints is avoided. This method helps to prevent cracks on walls

technically.

Types of Bonds

i. Flemish bond: This type of bond can be used for both single and double

walls. E.g.

Double Flemish bond

ii. Stretcher bond: This bond is used on half brick walls, with small thickness.

E.g.

iii. English bond: This type of bond is used for full wide brick bonding. It is

the strongest type of bond..e.g.

Floor


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Definition: Floor may be defined as a continuous horizontal platform constructed

between walls to support any load- both human and materials.

Types of Floors

There are basically three types of floors, namely:

i. Basement Floors: This is a type of floor that is located partly or completely

below the ground level. Some persons make use of the basement floor as

conference room. Eg.

Basement floor

(ii).Suspended Floors: This is a kind of floor that consists of wood, which are

nailed over solid lengths of timber. The ends are usually supported by the main

walls of the building. The solid timber that supports this type of floor are known as

joists. They are used in ancient storey buildings. E.g.


Suspended floor

(iii). Upper Reinforced Floors: These are solid floors containing reinforcements

like sand, concrete, cement, water, and steel. These are the type of floors used in

decking storey buildings.

Upper Reinforced floor

(iv). Solid Floors: These are floors made from ordinary or reinforced concrete. As

stated above, other forms of solid floors are ground floor, first floor, second floor,

third floor, etc. The diagram for solid floors looks like the one above.

(v). Precast Concrete Floor: These are already-made solid floor cast outside the

building site. They are assembled at the site.

Floor Finishes

Floors can be finished using one of the following methods:

i. Using terrazzo tiles, which is a combination of glass, marble, ebony with


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cement and then polished.

ii. Quarry tiles, which are cold to the feet when fully finished. They make for a

good impervious floor finish.

iii. Plastic tiles, which are produced from polyvinyl resin (PVR). It is easy to

maintain and manage.

iv. Sand screed or cement sand screed is used by most Nigerians. It is easy to

manage also.

v. Marble, made from limestone is used also and can be polished regularly.

vi. Wood blocks are used for decoration often times. It can be polished also.

REVIEW QUESTIONS

1. Define wall

2. List four types of walls

3. List five materials for making wall

4. List four functions of wall

5. What is bonding?

6. Define floor

7. List five types of floors

8. List four floor finishes.


LESSON 2.9

BUILDING CONSTRUCTION (DOORS AND WINDOWS )


1. List at least eight types of doors.

2. List at least four types of windows.

3. State at least three purpose of a window in a building.

4. List five materials each, used for making doors and windows.

Doors

Definition: Door can be defined as an openings into a building. Doors serve the

following purposes:

(i). doors provide security against burglary.

(ii). it provides a means of access into the building.

(iii). It facilitates ventilation.

(iv). It also admits a measure of light into the building.

Types of Doors

Doors are generally classified into two groups, namely exterior and interior doors.

(i). Exterior doors: These are doors that are put on the outer part of a building.

Some are the doors at the entrances of buildings or at the outer part of the kitchen

or garage. They are usually stronger.

(ii). Interior doors: As the name implies, these are the types of doors that are

placed inside the building. They include the bathroom door, bedroom doors and

kitchen doors.

For these classes of doors mentioned, they may be one of the following.

Types of Doors

1. Casement Door: These doors may be used for both exterior and interior


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purpose, depending on the taste of the builder. It contains different casement

designs. e.g.

Casement door (glass type)

2. Louvered Door: This is a door made of louvers. It is for internal use only. E.g.

Louvered doors

3. Sliding Glass Door: These doors are used in offices, shopping complexes and

shops. It slides side ways to allow for passage. It is an exterior door. E.g.

Sliding door


4. Flush Door: These are internal doors used in toilets, bedrooms and in the

kitchen. It is made of flush and plywood. E.g.

Flush door

5. French Doors: These are sophisticated, hardened doors, finished with French

polish, used for external purpose only. E.g.

French doors

6. Revolving Door: These are doors used in most public buildings like stadia,

supermarkets and banks. It is often a glass door. E.g.


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Revolving door

7. Roller Shutter: This is a metal, wide door used in big shops and warehouses or

garages. It can be rolled up and down. E.g.

Roller shutters

8. Panel Door: This door can serve both interior and exterior purpose. The

number of panels in this type of door gives it its complete and appropriate name.

For instance, below left, 2-panel door and on the right, 3-panel door. E.g.


2 and 3 Panel doors

9. Ledged Braced And Battened Door: These doors are used in rural areas. They

can also be used on wider openings at garages, shops and stores. E.g.

10. Headed Door: These are doors mostly used on worship buildings. They may

be semi-circle at the top, tudor, gothic or segmental in shape. E.g.

Headed doors


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Windows

Definition: Window may be defined as opening in the wall of buildings that serves

the following purposes:

(i). allows adequate flow of air into the building (ventilation).

(ii). allows light into the building.

(iii). gives additional beauty to the building.

(iv). it is also a means of viewing the outside world.

Windows are both for interior and exterior purposes.

Types of Windows

(i). Casement Window: This is a wooden or glass window built just like the

casement door. E.g.

Casement window

(ii). Louvered Window: As the name implies, this window is made of glass, either

transparent or translucent. E.g.

Louvered window


(iii).Sliding Glass Window: This is the most common type of window in Nigeria

in recent times. It allows for much ventilation and light, as a part of it can slide

sideways. E.g.

Sliding window

(iv). Bull’s Eye Window: This type of window is used for lamination and

decoration. It is made of a circular glass. E.g.

Bull’s eye window

(v).Dormer Window: This is a window attached to a chimney so that smoke can

escape through it. It is more for decorative, ventilation and lighting purposes these

days. E.g.

Dormer windows


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(vi). Semi Circular Or Segmental Window: These are windows used in religious

buildings. The upper part forms an arc. It is usually constructed with wood or

glass. E.g.

Segmental window

NOTE: It should be noted that the first three types of windows are commonly

used in Nigeria while the other three are special-purpose windows.

REVIEW QUESTIONS

1. List eight types of doors.

2. List four types of windows.

3. State three purpose of a window in a building.

4. List five materials each, used for making doors and windows

5. List at least five types of windows

LESSON 2.10

BUILDING CONSTRUCTION (ROOFS )


1. Define roof

2. List at least five materials used for roofing materials

3. List at least five types of roofs


4. State the uses of at least five types of roofs

5. Sketch at least five types of roofs.

ROOF

Definition: Roof is defined as a covering over buildings that may serve the

following purposes:

(i). protect the occupants from any harsh weather;

(ii). beautify a building;

(iii). to secure buildings.

Materials Used For Making Roof

(i). Clay tiles (ceramics).

(ii). Corrugated iron sheets.

(iii). Asbestos sheets

(iv). Aluminum span sheets

(v). Plastic sheets (usually for light)

(vi). Palm fronds.


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A typical standard roof

Types of Roofs

(i). Shed Roof or Lean-To Roof: These are small-sized roofs used for kiosks,

shops and boys quarters. Some are constructed resting on walls, hence they are

referred to as lean-to. E.g.

Shed roof

(ii). Gable or Collar roof: This is a type of roof that contains two sloping faces

with the walls rising into the roof at two opposite ends. It is the commonest type of

roof in Nigeria. It used for schools. Eg.


(iii).Hipped roof: This type of roof slopes down all four sides. The walls also rises

into the roof on all four sides. This roof is steeper than the gable roofs. It is suitable

for bungalows and storey buildings. Eg.

Hip roof

(iv). Butterfly roof: This type of roof is used for buildings with large spans. It is

sometimes called double shed roof, since it looks almost like one, but only bigger.

e.g.

Butterfly roof

(v). Combination roof: These are asymmetrical roofs used for most school

buildings where one face slopes steeper than the other. The greater slope covers the

rooms while the shorter slope covers the walkway. E.g


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(vi). Monitor roof: This is a type of roof used for factories and warehouses. It

usually contains two surfaces at different levels, where light is let into the building.

e.g.

Monitor roof

(vii). Half-Monitor roof: This roof looks like the monitor roof. The only

difference is that in this type of roof, one surface is lowered than the other.

Openings are fixed where light is let into the building. E.g.


Half Monitor roof

(viii). Arched roof: This type of roof has a rounded or curved shape like an arc. It

is also used for buildings with large spans, such as for filling stations, warehouses,

etc. e.g.

Arch roofs

(ix). Flat roof: These are roofs made of concrete castings (like slabs). Drainages

are provided through plastic pipes from the roof. E.g.

Flat roofs

(x). Mansard roof: These are roofs that contain double slopes on all four sides.

This type of roof is gradually being outdated. E.g.


145

REVIEW QUESTIONS

1. Define roof

2. List at least five materials used for roofing materials

3. List at least five types of roofs

4. State the uses of at least five types of roofs

5. Sketch at least five types of roofs.

FOR REVISION

QUESTIONS SEE PAGE 170

PART 3


LESSON-3.1

SIMPLE BLUE PRINT READING (SIMPLE DETAILS OF A BUILDING PLAN)

OBJECTIVES: At the end of this lesson, the student should be able to :

1.Define the following:

(a). Blue print reading

(b). Location plan

(c). Site plan

(d). Floor plan

2. Identify any elevation in building plan

3. Identify roof plan, window and door schedules

4. State the functions of the following:

(a). Septic tank

(b). Soak away pit

(c). Manhole

5. Identify at twenty building symbols.

Simple Blue Print Reading

Definition: Blue print is defined as a photographic print of a building plan drawn

in black and white lines on a blue background. E.g.

A sample of a blue print


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Plan: This is a detailed drawing of a building by an architect, showing the size,

shape and measurements of the building.

Building Plan: This is a line diagram showing the various apartments or rooms

drawn to scale showing the architectural symbols. E.g.

A building plan

Simple Details of a Building Plan-Areas In A Building Plan

1. Location Plan: The location plan shows all the buildings and areas

surrounding any particular house to be constructed. E.g.

A Location Plan Within Agbara-Lagos State


2. Site Plan: This is a drawing showing the length and breadth of the plot of

land for the required building and the length and breadth of the particular

building or flat to be erected. It also shows the access roads and its distance

to the location. E.g.

A typical site plan in Green

3. Floor Plan: This is plan that shows the detailed apartments including the

sanitary equipment in a proposed building. The floor plan is usually

sectioned (cut) as AA, BB, CC, DD, etc. e.g.

A Floor Plan

4. Sections on a Floor Plan: This is a plan showing the exact outlook of a

sectioned (cut) part of a building. The sectioned portion on any building

varies from one to the other. E.g.


149

A Section Plan for a Storey Building

5. Foundation Details: In this drawing, an architect shows the detailed

dimensions from floor level of a building to the ground level and to the

foundation. The different parts of the foundation, the materials and their

details are well analyzed in this drawing. E.g.

Foundation details on a building


Elevations

i. Front Elevation: This is a view of a building looking at the floor plan

directly from the front. It shows the height of the wall and the roof

pattern.

ii. Rear (Back) Elevation: This means looking at the floor plan from the back

(rear) view. This view also shows the height of the wall and the roof

pattern.

iii. Right Elevation: If one looks at the floor plan from the right side, the height

of the wall and the roof pattern, then we are talking about the right

elevation.

iv. Left Elevation: This means looking at the floor plan from the left hand

side. E.g.

Elevations of a building

Roof Plan

This is the plan view of a building as seen vertically from the top. This roof plan

shows the pattern of the building completely. E.g.


151

Roof plan

Doors and Window Schedule

This is a drawing that shows all the details and dimensions of every door and

window to be put in a building construction. It shows type and materials of every

of these openings. E.g.

Window Schedule Door Schedule


Septic Tank Details: A septic tank is a large tank designed to store sewage waste.

It usually built underground. E.g.

Septic tank

Soak Away Pit: This is a pit where liquid waste and effluent is deposited for

dispersion into the soil. In the construction of a septic tank, the soak away pit is the

final process where waste water filters into the surrounding subsoil. E.g.

Suck away pit

Manhole: This is a detachable cover, through which someone can enter to drain

should there be any blockage. It usually has a cover that prevents anything from

falling into it. E.g.


153

Manhole

Building Symbols


Review Questions

1.Define the following:

(a). Blue print reading

(b). Location plan

(c). Site plan

(d). Floor plan

2. Identify any elevation in building plan

3. Identify roof plan, window and door schedules

4. State the functions of the following:

(a). Septic tank

(b). Soak away pit

(c). Manhole

5. Identify at twenty building symbols.


155

LESSON-3.2

PERIODIC MAINTENANCE (DEFINITION AND TYPES)

OBJECTIEVES: At the end of this lesson, the students should be able to:

1. Define periodic maintenance

2. List and explain at least types of periodic maintenance

3. Undergo simple maintenance of machines in the Basic Technology

laboratory.

Definition: Periodic maintenance is defined as the regular maintenance that

prevents equipment from malfunctioning and undergoing sudden breakdown.

In the past, we have already stated that there are three types of maintenance

namely: preventive maintenance, predictive maintenance and corrective

maintenance.

Types of Periodic Maintenance

1. Short Term Routine Maintenance: This is the maintenance on a machine

on a daily or weekly basis. After using a woodwork or metalwork machine,

it is required that we clean, dust and lubricate after every use.

2. Medium Term Routine Maintenance: This type of maintenance is carried

out on an interval of between one month and six months. Cars, trucks, buses’

engines require this type of periodic maintenance. Household appliances like

generators, gas cookers and air-conditioners are involved here too.

3. Long Term Routine Maintenance: This type of maintenance is between

one to five years on a machine. This is especially true for rugged machines,

which have little or no moving parts.


Methods of Maintenance

Periodic maintenance involves the following works and methods:

i. Dusting of dirt from a machine.

ii. Adjusting or correcting a faulty part in a machine.

iii. Checking the very important areas of a machine. For instance, the electric

motor, the brushes, bearings, bolts and nuts, insulations and earthlings.

iv. Lubrication of moving parts.

REVIEW QUESTIONS

1. Define periodic maintenance

2. List and explain at least types of periodic maintenance

3. Explain four simple steps you will follow to carry out maintenance of a

machine in the Basic Technology lab


157

LESSON-3.3

PERIODIC MAINTENANCE

(FURNITURE -WOOD AND METAL)


1. Undergo the maintenance of a table

2. Undergo the maintenance of beds

3. Take care of chairs

4. Undergo the maintenance of aluminium pots

5. Undergo the maintenance of enamel pots

6. Take care of cutleries

Care of Furniture

Care of Tables

(a).Dust tables thoroughly each day.

(b).If painted or finished, wash carefully with warm slightly soapy water.

(c).Rinse and dry very well.


(d).Rub up with a clean soft duster.

(e).If polished, avoid the use of abrasive as they may scratch the surface

(f).If Formica-topped, do not put. very hot items on the table. Put hot food on table

mat.

(g). Dust thoroughly.

(h). Wash in such a way as to avoid water marks.

(i). Do not put very hot items on formica-topped tables. Put hot food on table mats.

(j). Avoid the use of abrasives as they will scratch the polished surface.

Care of Beds

(a). For beds, the sheets should be washed, ironed and kept clean always.

(b). The bed should be made every morning.

(c). The bed should be aired everyday.

(d). Regular dusting and polishing of the wood frame is very important.

(e). The bed should be turned down every night (i.e. the day time sheets removed

at night).

(f). For upholstery chairs, avoid making it very wet.

(g). Brush with a stiff upholstery brush to remove dust.


159

Care of Chairs

(a).Dust properly on a daily basis.

(b).For tubular chairs, do not scrape the metals with sharp objects.

(c).If it is a cushioned chair, do not cut the foams with razor blade and the wrapper

should be washed regularly.

(d).If the chair is upholstery type, avoid making it wet, dust very well and sponge

the upholstery with a solution of mild soap less detergent and warm water.

(e).For plastic chairs, dust properly and wipe over with a damp cloth and polish

with a clean dry duster.

Maintenance of Metals (Pots and Cutleries)

1.Care of Aluminium Pots


(a). Take care not to scratch the surface.

(b). New aluminium pots should be boiled out for at least 10 minutes so as to

prevent the formation of discoloration.

(c). After use, aluminium pots should be cleaned with a nylon sponge with a

washing paste.

(d). Always avoid the use of soda for washing pots.

2. Care of Enamel Pots/Dishes

(a). Enamel utensils should be washed after use, if possible use a fine powder like

vim.

(b). Avoid washing enamel dishes with coarse abrasive or metal sponges.

(c). High heat should be avoided, which may crack the enamel dish.

(d). Enamel dishes should be handled with care to avoid chipping.


161

4. Care of Cutleries

(a). Stainless steel cutleries should be cleaned with abrasive powder and dried with

clean cloth.

(b). Solid silver cutleries should be polished constantly because it tarnishes easily.

(c). Silver cutleries should be cleaned with wood ash and lime or lemon and rinsed

in warm soapy water, dried with cloth.

(d). Cutleries should be kept in a rack or drawer, that is easy to reach. Each in its

pile.

REVIEW QUESTIONS

1. How would you undergo the maintenance of a table?

2. How would you take care of your bed?

3. How should a student take care of chairs at home?

4. Explain steps you would take to undergo the maintenance of aluminium

pots

5. List four steps you would take to undergo the maintenance of enamel pots

6. How would you take care of cutleries in your home?


LESSON-3.4


( ELECTRICAL/ELECTRONICS) OBJECTIVES: At the end of this lesson, the student should be able to:

1. Undergo the maintenance of radios

2. Undergo the maintenance of refrigerator

3. Undergo the maintenance of Electric Kettle

4. Undergo the maintenance of electrical iron

5. Undergo the maintenance of air-conditioner

6. Undergo the maintenance of fans.

1. Care of Radio

(a). Do not tamper with the electrical parts of a radio. If any fault is detected, take

it to an experienced technician.

(b). Dust everyday with soft cloth, but be careful with delicate parts.

(c). If the radio is battery operated, do not allow dead batteries to become rotten

inside the radio.


163

2. Care of Refrigerators

(a). Avoid putting hot food in the refrigerator.

(b). Always keep the refrigerator door tightly closed, to avoid the escape of cold

air to the environment.

(c). Do not place a refrigerator too close to the wall. This is to allow the circulation

of air over the coils at the back.

(d). Arrange food items in the refrigerator properly so that air can circulate and

keep foods cool.

(e). Check the refrigerator regularly for any spoilt food. These must be removed

immediately.

(f). The inside and outside of the refrigerator should be washed occasionally.

(g). Defrost the refrigerator once a week (if your area has constant power anyway).

Thick frost reduces the cooling effect of the refrigerator.


3.Care of Electric Iron

(a). Do not place the surface of any iron on the floor at any time.

(b). Avoid twisting the cord.

(c). Do not drop the iron because this may damage it.

(d). Use any appliance according to the maker’s instructions.

(e). Do not iron over zips and hooks since this may scratch the smooth surface.

(f). As soon as the cord shows a little visible sign of wear, kindly replace it

immediately with similar cable.

4. Care of Air-Conditioner

(a). In case of mechanical or electrical fault, always refer to an experienced

technician.

(b). Always operate an air-conditioner according to the manufacture’s guideline.

(c). Occasionally switch off the air-conditioner at the outlet socket and use a soft

cloth to dust all over the appliance.

(d). All doors and windows must be closed when the air-conditioner is put on.


165

5. Care of Fans

(a). When any fault is detected, an experienced personnel should be contacted for

repairs.

(b). Use fans according to the manufacturer’s manual.

(c). Whenever the fan is not needed, it should be switched off and unplugged from

the socket.

(d). To clean a table or standing fans, open the guard and dust the blades. Dust

first, then clean with damp cloth and dry every other part very well.

(e). For ceiling fans, clean the blades regularly with care without bending the

blades.

6. Care of Electric Kettle

(a). Water should not be left too long in an electric kettle, especially overnight.

This can discolour the kettle.

(b). After using an electric aluminium kettle, clean with a nylon sponge with fine

abrasive powder to retain its quality.

(c). Wash kettles used on kerosene or gas cookers with fine abrasive powder or


paste but with more pressure.

REVIEW QUESTIONS

1. Do you have a radio in your home? If yes, how can you care for it?

2. Explain how you can undergo the maintenance of a refrigerator.

3.How would you undergo the maintenance of an electric kettle.

4. How would you care for your electrical iron?

5. Explain four ways you may maintenance your air-conditioner.

6. How can you care for your fans?


167

LESSON-3.5

FAULT DETECTION


1. Define troubleshooting.

2. Differentiate between analogue and digital meters.

3. State how an instrument can be used to detect a fault in an appliance.

4. List six fault detection instruments.

5. State how to use an electric current tester.

6. Mention three fault detection processes.

Definition: Fault detection, also known as trouble shooting is a form of

maintenance for electronics. Since electrons move about in some gadgets, they are

therefore referred to as electronics.

Trouble-Shooting: Troubleshooting is the process of finding likely fault in

equipment, machine and electrical appliances by using appropriate tools.

In trouble shooting, it is assumed the problem is not known. As such, it involves a

trial and error method of detecting and locating a fault in a machine.

Fault Detection Tools and Instruments

i. Voltage Indicator: This instrument is to check whether voltage exists

across two points in a circuit. There is the Analogue meter with a

deflective finger indicator and the Digital meter which displays the exact

value of the electronic device even in decimal. The digital meter is easier

to read.

However, in the absence of these meters, a simple voltage indicator of a

lamp connected to a lamp holder and two wire terminals can be used.

E.g.


Voltage indicator

ii. Electric Current Tester: This looks like a screwdriver that has a red bulb

inside it when the tip torches a live wire while a finger is placed on the

cap of the insulated handle. E.g.

Current tester

iii. Continuity Tester: This is also known as a multimeter. It can be used to test

the flow of current, as voltage indicator, as insulation tester and other

tests. E.g.

Continuity tester

iv. The Oscilloscope: This is a general-purpose instrument used for measuring

small voltages and current. It is also used for the maintenance of

electronic equipment and laboratory work. They have LCD or LED

screens and a fast analogue-to-digital converters and digital signal

processors. E.g.


169

An Oscillator

v. Insulation Tester: The insulation tester is known as the megger, which is

used to test earth leakages that results in shocks. E.g.

A Megger

vi. Soldering Iron: It is used to solder electronic elements to the panel. It can

also be used to melt soldered components for proper examination. E.g.

Soldering iron

Fault Detection Process

To detect fault in any electrical appliance, follow the steps listed below:

i. Understand the operation of the appliance.

ii. Check the connecting cord that transmits power from the mains into the

appliance.

iii. Check the fuse in the plug (if it is well fused).

iv. If it a heating appliance (like electric iron), check the continuity of the

heating element.


Review Questions

1. Define troubleshooting.

2. Differentiate between analogue and digital meter.

3. State how you would make use of the electric current tester.

4. State how a meter can be used to detect a fault in an appliance.

5. Mention five detection instruments you have learned.

6-13.Revision- JSCE!

JSCE!! JSCE/ NECO. DISCLAIMER: DISCLAIMER: THE QUESTIONS BELOW ARE STRICTLY

FOR REVISION PURPOSES ONLY. ANY QUESTION(S) IN YOUR

EXAMINATION SIMILAR TO ANYONE IN THIS PRACTICE SESSION IS

SIMPLY A COINCIDENCE.

ANSWERS WILL BE

SUPPLIED ON REQUEST

BY MAIL TO [email protected]

I WISH YOU SUCCESS IN YOUR EXAMINATION-AMEN!

BASIC TECHNOLOGY PART- A

TERM ONE

CAREER PROSPECTS AND OPPORTUNITY IN TECHNOLOGY

(QUESTION SOURCE: NATION BUILDING BASIC TECHNOLOGY 3,

By Ajayi E.K.)

mailto:[email protected]


171

1. ………………… can be defined as the scientific knowledge used in practical ways to

meet and satisfy human needs and comfort.

(a) science (b) knowledge (c) technology (d) production (e) career

2. The following are products of technology found in homes, except

(a) television (b) radio (c) cell phone (d) wall clock (e) sand

3. The following are products of technology found in industry, except

(a) water (b) fax machine (c) computer (d) oven (d) photocopy machine


WOOD AND METALS

4. The grown trees are felled down to produce what is referred to as ………..

(a) coal (b) timber (c) cotton (d) palm wine (d) palm roof

5. ………… is obtained from grown trees which can be used in building or for making

things

(a) wood (b) trees (c) sand (d) stone (d) cement

6. …………. acts as a supports for the trees

(a) leaves (b) roots (c) bark (d) tree (e) branches

7. ……………. holds or anchors the tree strongly on the ground

(a) stem (b) roots (c) bark (d) tree (e) leaves

8. Wood can be classified into …………….. types

(a) 2 (b) 4 (c) 8 (d) 6 (e) 3

9. Which of the following wood is a deciduous wood?

(a) softwood (b) physical wood (c) artificial wood (d) hardwood (e) strong wood

10. Mahogany, Oak, Afara, Iroko etc are the examples of ……………… wood

(a) softwood (b) hardwood (c) closure (d) physical (e) artificial

11. Spruce, Cypress, Pine, and Cedar etc are examples of …………… wood

(a) physical (b) soft (c) hard (d) artificial (e) strong

12. ……………. can be defined as the cutting down of trees with the use of power chain saw


(a) pulling of trees (b) up rooting of trees (c) felling of trees (d) wood defects (e)

seasoning of trees

13. …………… is the method of using sawing machine to cut the log into determined

acceptable sizes in the market

(a) seasoning of wood (b) conversion of trees (c) wood defects (d) felling of trees

(e) conversion of trees

14. ……………. is the method of drying excess water or removing excess water in the wood

(a) wood defects (b) felling of trees (c) forms of wood (d) seasoning of wood (e)

conversion of wood

15. There are …………… methods of seasoning wood

(a) 2 (b) 4 (c) 6 (d) 8 (e) 10

16. …………… can be defined as the process of using chemical to protect the wood from

attack

(a) preservation of wood (b) felling of woods (c) seasoning of wood (d) forms of

wood (e) wood defects

17. Metal can be classified into ………………

(a) 4 (b) 3 (c) 2 (d) 5 (e) 1

18. …………… is the tendency of metals to melt into liquid when heated.

(a) toughness (b) ductility (c) sound test (d) fusibility (e) density

19. …………….. is the tendency of metals to be stretched into a thin wire

(a) fusibility (b) ductility (c) density (d) toughness (e) sound test

20. ………….. is the tendency of metals to break easily

(a) brittleness (b) density (c) sound test (d) fusibility (e) toughness

21. ……………. is obtained when two or more metals are mixed together

(a) metals (b) alloy (c) structures (d) ferrous (e) non-metallic

22. …………. is the process of extracting metal from its ore by heating and melting the metal

ore

(a) iron ore (b) alloy (c) smelting (d) pig iron (e) ore

23. How many types of ore do we have?

(a) 3 (b) 6 (c) 2 (d) 7 (e) 4


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24. ………….. is the making of objects by pouring molten metal into a ground

(a) smelting (b) casting (c) smoothing (d) burning (e) moulding

25. ……………. are projections which enable the core to sit well after the pattern is removed

(a) prints (b) smelting (c) casting (d) smoothing (e) moulding

26. …………… is the art of processing earthly materials into ornamental objects though the

application of high heat.

(a) decoration (b) ceramics (c) glass (d) prints (e) potter’s wheel

27. …………… is formed naturally during volcanic eruption

(a) glass (b) decoration (c) ceramics (d) anneal (e) timber

28. ……………. is to heat glass or metal and allow it to cool gradually so as to make it

harder

(a) anneal (b) timber (c) glass (d) ceramics (e) casting

29. There are ………….. main classes of glass

(a) 3 (b) 4 (c) 5 (d) 2 (e) 6

30. ………….. is produced from the latex obtained from rubber trees

(a) artificial rubber (b) natural rubber (c) physical rubber (d) coal (e) limestone

31. ……………. is a natural substance that form the cell wall of all plants and trees

(a) cell wall (b) cellulose (c) metal (d) rubber (e) limstone

32. …………… are elastic substances that can be stretched and do not allow liquids to pass

through it.

(a) rubber (b) limestone (c) metals (d) iron (e) ore

33. ………… is the process of adding sulphur to raw rubber at high temperature

(a) storm (b) carbon black (c) vulcanization (d) rubber (e) limestone

34. …………. Does not melt under heat but instead burnt and becomes blackish brown

(a) thermosetting (b) thermoplastic (c) carbon black (d) vulcanization (e)

limestone


(CERAMICS, GLASS, PLASTIC AND RUBBER)

35. Glass can be classified into …………….


(a) 3 (b) 2 (c) 4 (d) 6 (e) 5

36. ………….. is the art of processing earthly materials into ornamental objects through the

application of high heat

(a) ceramics (b) glass (c) plastics (d) rubber (e) decoration

37. ……………. is formed naturally during volcanic eruptions

(a) plastic (b) ceramics (c) glass (d) rubber (e) anneal

38. …………….. is to heat glass or metal and allow it to cool gradually (slowly) so as to

make it harder

(a) plastic (b) glass (c) decoration (d) anneal (e) rubber

39. There are …………… types of plastic material

(a) 3 (b) 2 (c) 4 (d) 5 (e) 1

40. Plastic processing involves the following processes except

(a) casting (b) moulding (c) forming (d) calendaring (e) rubber

PICTORIAL DRAWING

41. There are ……………………. Main methods of pictorial drawing

(a) 3 (b) 2 (c) 4 (d) 5 (e) 6

42. ………….. drawing can be defined as a method that identifies solid objects showing

three dimensions in one view

(a) geometry (b) pictorial (c) orthographic (d) solid (e) plane

43. …………….. is the portion of flat or plane surfaces bounded by one or more lines.

(a) solid figures (b) plane figures (c) polygon (d) triangle (e) circle

44. ……………. has length, breadth and thickness or depth

(a) solid figures (b) plane figures (c) pictorial (d) isometric (e) surface

45. Surface has ……………………. and ……………………..

(a) depth and length (b) length and breadth (c) length and height (d) height and

width (e) none

46. There are ………………… types of oblique drawing

(a) 3 (b) 4 (c) 2 (d) 6 (e) 5

OBLIQUE DRAWING AND DIMENSION


175

47. …………….. drawing is a type of drawing that recognizes solid objects in three

dimensions with front face perpendicular to the plane of the paper

(a) oblique (b) isometric (c) triangles (d) shapes (e) square

48. ………….. is when the oblique drawing is made without any reduction in oblique length

(a) cavalier (b) cabinet (c) oblique (d) diagrams (e) isometric

49. Oblique drawing can be classified into …………….. types

(a) 5 (b) 3 (c) 2 (d) 4 (e) 1

WOODWORM MACHINES

50. ……………… is machine capable of slicing the logs of timber into various sizes

(a) band saw (b) calipers (c) hammer (d) circular (e) sea-saw

51. There are ………………. types of machine saw

(a) 2 (b) 4 (c) 6 (d) 8 (e) 5

52. …………… can be used to make bevel, tenon among other operations on wood

(a) calipers (b) hammer (c) surface planner (d) saw (e) circular saw

53. …………… machine is mainly used for planning wood to produce accurate thickness as

needed

(a) hammer (b) surface planner (c) saw (d) calipers (e) thicknessing machine

54. ……………. is a machine used for wood turning operations

(a) wood (b) wood lathe (c) calipers (d) hammer (e) saw

SIMPLE WOODWORK PROJECTS

55. ………………. is an activity involving a special skill at making forms of wood either

with the use of hand or machine

(a) woodwork (b) wood grinding (c) wooding (d) butt wood (e) halving wood

56. ………….. is the type of joint whereby the rectangular end of the member wood fits

against the flat surface of the other member wood

(a) joint (b) butt joint (c) wood joint (d) work joint (e) bulled joint

57. There are ……………….. types of woodwork joint

(a) 3 (b) 2 (c) 4 (d) 5 (e) 6


58. …………… are the joints obtained when half thickness or width of the members are cut

out to give flush faces for meeting or crossing members.

(a) but joints (b) halving joints (c) joints (d) walls (e) rebated joints

59. …………… is the strongest of other joints for making corner joints in wooden containers

and cabinet drawers work.

(a) dovetail (b) joints (c) walls (d) hammer (e) halving joints

60. …………… can be defined as a substance for making materials stick together

(a) adhesive (b) resin (c) casein (d) glue (e) P. V. A.

61. Which of the following is NOT a type of nail

(a) countersunk head screw (b) oval nail (c) panel pin (d) clout pin (e) screw nail

62. Which of the following is regarded as a fitting

(a) hinge (b) sand paper (c) panel pin (d) clout pin (e) screw nail

63. Which of the following is used for finishing

(a) glue (b) lock (c) nail (d) smooth plane (e) hinge

64. ……………… is the type of nail that is strong and generally used in building work

(a) oval nail (b) lost-head round nail (c) screw nail (d) clout nail (e) panel pin

65. …………… is the type of nail that has a twisted length up to the head for a proper

increase of the frictional grip

(a) screw nail (b) panel pin (c) clout pin (d) oval pin (e) wire round nail

66. ………….. is the type of screw used when the head is expected to be flush with a

particular surface of wood.

(a) countersunk (b) panel (c) oval (d) round head (e) raised head

67. …………….. are the metallic components used for fastening wooden parts together

(a) butt hinge (b) flat hinge (c) tee hinge (d) hinges (e) fittings

68. There are ……………… types of fittings

(a) 2 (b) 4 (c) 6 (d) 8 (e) 10

69. ………….. is the type of hinges that is used for external doors

(a) hinges (b) box lock (c) tee hinge (d) butt hinge (e) flat hinge

70. …………… is a type of lock that is used for boxes and chest

(a) locks (b) hinges (c) drawer lock (d) mortice lock (e) box lock

71. ………….. are substances with glue coated hard minerals forming a rough surface for the

purpose of standing


177

(a) abrasive (b) metals (c) hinges (d) locks (e) beautification

72. The following are useful in the preparation of abrasives except

(a) silicon carbide (b) cloth (c) paper (d) resin glue (e) saw dust

73. ……………. is the type of abrasives that is used for fine and coarse smoothing

(a) glass paper (b) silicon coated (c) tungsten carbide coated (d) aluminium oxide

coated (e) garnet coated

74. …………… is the type of abrasive that is purposely used for durability

(a) aluminium oxide coated (b) tungsten carbide coated (c) glass paper coated (d)

silicon coated (e) garnet coated

75. ……………. is the final preparation of wood surface to receive finishes

(a) wood preparation (b) wood work shop (c) wood finishing (d) wax polish (e)

French polish

76. ………….. can be defined as the materials applied to the surface of the finished wood for

the purpose of preservation or beautification.

(a) wood finishes (b) wood preparation (c) wood finishing (d) wood joint (e) wood

work

77. The following are the reasons why we apply wood finishes except

(a) for general outlook (b) to be attractive (c) to protect the wood against insect (d) to

protect the wood against fungus attack (e) to make it available

78. The following are the categories of wood finishes except

(a) lacquers (b) varnish (c) French polish (d) wax polish (e) engine oil

79. The following are grades and types of paint except

(a) metallic (b) egg shell (c) sandy (d) glossy oil (e) oil resin emulsion

(METAL WORK MACHINE)

80. The basic machine tools are the following except

(a) centre lathe (b) shaping machine (c) planning machine (d) drill press (e) spraying

machine

81. …………… are used for producing flat surfaces which cannot be achieved on milling

machine


(a) planning machine (b) shaping machine (c) drill press (d) centre lathe (e) lathe

machine

82. ………….. machine is used for producing flat surfaces including slots and vee grooves

(a) milling (b) shaping (c) planning (d) centre lathe (e) drill press

83. ……………. Machine is used to remove a waste or unwanted metal with the use of

abrasive mounted on rotating wheels

(a) grinding machines (b) printing machines (c) shaping machines (d) drill press (e)

rolling machine

84. …………… is the machine used in the machine shop to produce holes of different sizes

on metals

(a) milling machines (b) drill press (c) grinding machines (d) shaping machines (e)

planning machines

85. …………… is used for cutting various large or big metals of different shapes which the

hacksaw cannot cut.

(a) saw (b) calipers (c) cutlass (d) hoe (e) power hack saw

86. How many parts of centre lathe machine do we have?

(a) 4 (b) 3 (c) 2 (d) 5 (e) 1

SIMPLE METAL WORK PROJECT

87. ………….is simply the use of metal sheet of reasonable thickness in making different

shapes of object

(a) sheet metal work (b) metal work (c) shade development (d) wood work (e)

development

88. ……………. is the line where two ends meets and joined together

(a) work (b) metal joint (c) seam (d) shape (e) development

89. ………….. is the spreading out of various faces of objects in horizontal plane

(a) shape development (b) metal (c) seam (d) joint (e) wood work

90. …………… are used for marking tin-plates

(a) dividers (b) punches (c) steel rule (d) micro meter (e) snip

91. Which of the following is NOT among the forging operations?

(a) twisting (b) bending (c) hardie (d) drawing down (e) upsetting

92. …………….. is used for taking linear measurements

(a) steel rule (b) snip (c) punches (d) sliding level (e) scriber


179

93. ……………… is the hammering of hot metal and shaping it into the required shape

(a) forging (b) snips (c) scriber (d) calipers (e) screws

94. …………… are used for cutting metals and they function like the cloth cutting scissors

(a) chisel (b) scriber (c) snips (d) screws (e) calipers

95. The following metals can be used for soft soldering except

(a) aluminium (b) copper (c) zinc (d) brass (e) bronze

96. …………….. is used for forming hollow shapes or grooves on metal

(a) fuller (b) tong (c) hardie (d) chisel (e) anvil

97. …………….. is used for cutting metal into shapes

(a) fuller (b) hardie (c) chisel (d) tongs (e) anvil

98. …………… is the process of increasing the thickness of a metal by reducing its length

(a) upsetting (b) fuller (c) hardie (d) tongs (e) chisel

99. …………. is the process of treating the surface metals so as to prevent rusting, improves

its life span and make it pleasant to look at.

(a) metal protective (b) metal finishes (c) metal work (d) metal finishing (e) metal

wood work joint

100. ………….. can be defined as a method of joining metals by sticking them together with

the use of an alloy

(a) soldering (b) brazing (c) flux (d) metal (e) painting and spraying

JSS3 BASIC TECHNOLOGY OBJECTIVE QUESTIONS

PART -B

METAL JOINING

(SOLDERING AND BRAZING)

1. The following metals can be soft soldering except

(a) aluminium (b) copper (c) zinc (d) brass (e) bronze

2. ………….. can be defined as a method of joining metals by sticking them together with

the use of an alloy

(a) soldering (b) brazing (c) flux (d) metal (e) painting and spraying

3. The two types of soldering are …………….. and …………………


(a) physical and artificial (b) hard and soft (c) natural and synthetic (d) hard and

dry (e) dry and wet

4. The following are metals that can be soft soldered, except

(a) steel (b) cast iron (c) zinc (d) copper (e) brass

5. There are …………….. types of flux

(a) 2 (b) 4 (c) 6 (d) 8 (e) 5

6. …………… is the joining of metals with a solder consisting of brass or a silver alloy

(a) flux (b) soft soldering (c) solder (d) brazing (e) hard soldering

7. Which of the following is NOT a method of joining metals?

(a) soldering (b) roping (c) using mechanical fastener (d) welder (e) riveting

TERM TWO

MECHANICAL ENERGY TRANSMISSION SYSTEM

(FRICITION)

8. ……………… can be defined as the force that resists the motion between two surfaces in

contact

(a) mechanism (b) friction (c) fiction (d) motion (e) metal

9. Which of the following is NOT a type of friction?

(a) dry friction (b) internal friction (c) fictitious friction (d) fluid friction (e)

lubricated friction


(EFFCTS OF FRICTION AND ITS REDUCTION)

10. The following are effects of friction, except

(a) friction brings heat (b) friction aids running (c) friction reduces efficiency (d)

friction results to loss of power (e) friction gives power


(DRIVE MECHANISM)


181

11. ……………. can be defined as the force that resists the motion between two surfaces in

contact or when one move relative to other.

(a) mechanism (b) friction (c) fiction (d) friczing (e) metals

12. …………….. is a mechanical energy transmission system of transmitting power from

one sprocket wheel to the other on greased teeth

(a) chain drives (b) belt drives (c) friction (d) electric grinder (e) gear drive

13. …………….. is a mechanical energy transmission system of transmitting power with the

use of toothed edges wheel that mesh with one another

(a) gear drive (b) chain drives (c) belt drives (d) friction (e) electric movers

14. ……………… is the arrangement of gears such that power can be transmitted

(a) chain drives (b) electric grinder (c) gearing (d) belt drives (e) gear movers

15. There are ………………. Types of gear

(a) 4 (b) 3 (c) 2 (d) 5 (e) 1

16. …………… can be defined as a relationship between two gears in which it shows how

much larger the speed of one gear is than the other

(a) gear ratio (b) driven gear (c) driving gear (d) bevel gear (e) chain drives

17. ……………. Simply means the engagement of the teeth of the gears

(a) driven gear (b) driving gear (c) chain drives (d) meshing of gears (e) gear ratio

18. ……………. is the gear that transmits speed to the other gear

(a) driving gear (b) gear ratio (c) driven gear (d) chain drives (e) bevel gear

19. …………… is the gear that receives the impulse of the speed from the other gear

(a) gear ratio (b) driven gear (c) driving gear (d) bevel gear (e) chain drives

MECHANICAL TRANSMISSION SYSTEM

(DRIVE MECHANISM)

20. ………… can be defined as the movement of mechanical components in engineering

systems.

(a) motion (b) friction (c) fiction (d) rotary motion (e) linear motion

21. There are……………. types of motion

(a) 3 (b) 4 (c) 5 (d) 6 (e) 2

22. ……………. is a type of motion that occurs in form of a straight line.


(a) linear motion (b) rotary motion (c) motion (d) friction (e) fiction

23. …………….. is the type of motion that occurs in circular form either clockwise or anti

clockwise direction

(a) fiction (b) friction (c) rotary motion (d) linear motion (e) motion

24. ……………… are mainly used to control motion, either to slow down or bring to an

eventual stop as wanted

(a) ratchet (b) brakes (c) clutch (d) engine (e) gear

25. ……………… is a device used for transmitting intermittent motion in one direction only

(a) clutch (b) gear (c) brakes (d) engine (e) ratchet

26. ……………. is a machine use for lifting loads?

(a) pulleys (b) screw jack (c) bench vice (d) brakes (e) engine

27. …………….. is a wheel with a grooved rim in which a rope or chain passes

(a) pulleys (b) bench vice (c) brakes (d) wheel barrow (e) engine

MECHANICAL TRANSMISSION SYSTEM

(AIRFLOW AND PNEUMATIC)

28. ………….. can be defined as the continuous and steady movement of air in a particular

direction

(a) air pump (b) air flow (c) human mouth (d) wind turbine (e) streamling

29. Airflow can be generated in the following ways except

(a) fan (b) balloon (c) bellow (d) human mouth (e) air pump

30. …………… is a machine that grinds grain into flour

(a) windmill (b) streamlining (c) human mouth (d) wind turbine (e) wind power

31. ……………… is the use of compressed air to make machine work.

(a) streamlining (b) pneumatic (c) wind turbine (d) air pump (e) windmill

32. …………… is an air pump that is driven by an electric motor or internal combustion

engine

(a) compressor (b) receiver (c) air flow (d) air pump (e) wind turbine

33. The compressed air is usually stored in a strong metal tank called the ………….

(a) receiver (b) pump (c) air pump (d) turbine (e) compressor


183

34. …………… is the flow of liquids or fluid through pipes under pressure in machineries

for doing work.

(a) sliding doors (b) hydraulic (c) engine (d) brake (e) clutch


35. Which of the following does not use electricity?

(a) refrigerator (b) cooker (c) T. V (d) air conditioner (e) bench vice

36. ……………. is a device that contains a short length of thin wire which melts and breaks

when the current exceeds save value

(a) fuse (b) wire (c) battery (d) current (e) circuit

37. ……………. is the instrument used for measuring current flow.

(a) thermometer (b) amometer (c) barometer (d) ammeter (e) meter

38. ………….. is a closed path of wires and other electrica l equipment or materials

(a) electric circuit (b) electrician (c) electric circuit (d) metallic (e) current

39. Current flow is measure in ………………

(a) voltage (V) (b) ampere (A) (c) joules (J) (d) power (P) (e) watt (W)

40. ………….. is the instrument used for measuring voltage

(a) voltmeter (b) joules (c) voltmeter (d) power (e) thermometer

41. …………… is the measure of the magnitude of resistors opposing the flow of electric

current

(a) resistance (b) resistivity (c) current (d) electricity (e) electric circuit

42. Voltage is measured in ……………

(a) joules (J) (b) energy (E) (c) watt (W) (d) volts (V) (e) thermometer (T)

43. …………….. is the instrument used to measure resistance

(a) ohmmeter (b) volt (c) ohm (Ω) (d) joules (e) watt

44. …………….. is the measure of the force of current flow in a circuit

(a) voltage (b) energy (c) power (d) watt (e) voltmeter

45. ………….. is the pressure with which electric current flows round a closed circuit


(a) resistance force (b) electric current (c) current flow (d) voltage (e)

electromotive force

46. …………… converts electrical energy into heat energy

(a) resistors (b) resistance (c) voltage (d) current flow (e) air flow

47. The following are the factors determining the resistance value of materials except

(a) temperature of the material (b) loss of materials (c) length of the materials (d)

cross sectional area of the materials (e) resistivity of the materials

48. …………. are used to convert alternating current to direct current

(a) rectifier circuit (b) current flow (c) air flow (d) electric circuit (e) electricity

49. The following are the types of switch except

(a) push bottom switch (b) toggle switch (c) slides switch (d) micro switch (e)

push-pull switch


(WIRING TOOLS AND MATERIALS)

50. …………… refers to the point in the house where electrical services goes from the main

grind into the house

(a) service entry (b) hammer (c) rectifier (d) panel board (e) branch circuit

51. ………… is the control centre when it comes to electrical wiring

(a) branch circuit (b) panel board (c) a fish tape (d) rectifier (e) hammer

52. The following are the simple wiring tools except

(a) A fish tape (b) voltmeter (c) hammer (d) A tape measure (e) bradawl


(FOUNDATION, TYPES AND USES)

53. ……………… can be defined as an underground structure upon which a building is

erected

(a) foundation (b) pillar (c) site plan (d) building plan (e) plan

54. The following are the types of foundation except

(a) strip foundation (b) building foundation (c) pile foundation (d) raft foundation

(e) stepped foundation

55. The following are functions of foundation except


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(a) foundation is a support for the inhabitants (b) foundation supports the weight of the

roof (c) it distributes the weight of the building to the soil (d) foundation support the

weight of the wall (e) foundation serves as weakness to the roof

56. What is the meaning of d. p. c?

(a) damp pad course (b) damp proof coarse (c) down part course (d) down pad course

(e) damp proof coarse

57. Which of the following is the ability of the soil to carry load?

(a) strip foundation (b) soil texture (c) bearing capacity (d) stony soil (e) rocky

foundation

58. There are …………….. types of soil

(a) 3 (b) 4 (c) 5 (d) 2 (e) 6

59. The following are properties of clay soil except

(a) it has fine particles (b) it is water drainage (c) it is impermeable (d) it is highly

compressible (d) it sticks when wet and dries very slowly

60. ………………. is the digging of trenches for the building foundation using the

foundation plan.

(a) excavation (b) plan (c) soil (d) building (e) spade

61. The following are properties of organic soil except.

(a) it has fine particles (b) it is water retentive (c) it is soft (d) it is compressible (e)

it is spongy and springy to walk on

62. Peat, humus and swampy soil can be regarded as ……………. Soil

(a) fine grained (b) coarse grained (c) highly organic (d) clayed (e) sandy

63. Timbering depends on the following except

(a) depth of excavation (b) length of time (c) type of subsoil (d) climatic condition

(e) tools

64. Choosing foundation depends on one of the following

(a) type of water to use (b) type of building (c) personnel (e) tools to use (e) cement

to use

65. Which of the foundation below is good for sloppy land

(a) strip (b) pad (c) raft (d) stepped (e) pile



(WALLS AND FLOORS)

66. …………… can be defined as a building part that is built on the foundation to support

the roof

(a) doors (b) floors (c) walls (d) building (e) foundation

67. The following are functions of wall, except

(a) to oppose the passage of noise (b) to be reasonable in cost (c) to resist weather,

particularly moisture and cold (d) to safely carry the structural loads placed upon it

(e) to be very expensive

68. ………….. which of the following is NOT a type of wall?

(a) partition (b) shared (c) portable (d) boundary (e) rock

69. …………….. is a wall for the purpose of separating rooms or dividing a room

(a) shared room (b) partition wall (c) boundary wall (d) portable wall (e)

separation wall

70. ……………… are used where the walls of a room are frequently open to form one large

floor area

(a) separation wall (b) partition wall (c) shared wall (d) movable wall (e)

foundation

71. The following are materials used for making walls, except

(a) timber product (b) glass (c) blocks (d) metal (e) water

72. The following are types of floor except

(a) suspended floor (b) bonding floor (c) solid floor (d) precast concrete floor (e)

concrete slab floor


(DOORS, WINDOWS AND OPENING)

73. The following can be found in doors except

(a) rabbet (b) jamb (c) architraves (d) lining (e) fan light

74. ………….. is an opening in wall that allows fresh air and light to enter and move around

the building

(a) walls (b) window (c) door (d) metal (e) aluminium

75. The following are materials used for making doors and windows except


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(a) timber (b) glazing (c) metal (d) fitting materials (e) coal

76. The following are types of doors except

(a) lintel door (b) flush door (c) sliding door (d) folding door (e) revolving door

BUILDING CONSTRUCTION (ROOFS, TYPES AND USES)

77. The following are types of roof except

(a) d. p. c. (b) lean-to-roof (c) shed (d) hipped (e) arched

78. Which of the following is NOT a roofing material

(a) slate (b) aluminium (c) sancrete hollow block (d) zinc (e) grass

79. A B. C.

Identify A above (a) scraper (b) rammer (c) wood float (d) bricklayer trowel (e)

spirit level

80. Identify B above (a) scraper (b) rammer (c) wood float (d) spirit level (e) bricklayer

trowel

81. Identify C above (a) scraper (b) rammer (c) spirit level (d) wood float (e) bricklayer

trowel

TERM THREE

SIMPLE BLUE PRINT READING AND RURAL/URBAN WATER SUPPLY TO

BUILDINGS

82. ………….. is the photographic prints of a plan for a building drawn with white lines and

a blue background

(a) blue print (b) red print (c) white print (d) yellow print (e) magenta print

83. ……………. Is drawn by the architect and it shows a detailed drawing of the drawing

such as sizes shapes etc


(a) building plan (b) plan (c) location plan (d) site plan (e) yellow print

84. ……………… is designed to store sewage in houses

(a) soak away (b) manhole (c) plan (d) septic tank (d) site plan


85. ………….. can be defined as the act of keeping engineering equipment in good condition

by regular checking and servicing at a particular time.

(a) maintenance maintenance (b) preventive maintenance (c) periodic maintenance

(d) corrective maintenance (e) supportive maintenance

86. The following are the importance of maintenance, except

(a) it increases the span of equipment (b) it prevents accident (c) it causes loss (d) it

makes work easy to overcome (e) it prevents equipment from breaking down

87. There are ……………. types of maintenance

(a) 3 (b) 2 (c) 4 (d) 5 (e) 7

88. Simple maintenance methods include the following except

(a) cleaning (b) dusting (c) breaking (d) oiling (e) washing

89. The following are the importance of periodic maintenance records except

(a) makes plan (b) makes budgets (c) prepare for tax assessment (d) obtain credit

from banks (e) for depreciation purposes


(KITCHEN UTENSILS AND FURNITURE)

90. ………….. are used for cooking and then could be used for storage

(a) cooking pot (b) kettle (c) plates (d) cutlery (e) fry pan

91. …………… is used for coating plates or pots or prevent them from rusting

(a) engine oil (b) palm oil (c) enamel (d) emulsion paint (e) grease

92. Furniture may be finished with the following except

(a) paint (b) polished (c) varnish (d) formica (e) grease


(ELECTRICAL AND ELECTRONICS APPLIANCES)

93. ……………. are used to preserve food items

(a) cutlery (b) cooking pots (c) refrigerator (d) fry pan (e) kettles


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94. An item which cuts off the current when the temperature of the hotness is to exceed the

adjusted value is called ……………

(a) iron (b) standing fan (c) electric fan (d) electric iron (e) thermostat

95. Which of the following is not a type of electric fan

(a) table fan (b) stood fan (c) standing fan (d) ceiling fan (e) heat extractor

96. The tariff of the electric power consumed is charge on …………… basis

(a) weekly (b) daily (c) yearly (d) hourly (e) monthly

FAULT DETECTION

97. …………… is the process of finding likely fault in electronics using appropriate tools.

(a) fault detection (b) analogue meter (c) digital meter (d) operational chart (e)

electric tester

98. …………… will display the exact value of the electronic devices in decimal

(a) analogue meter (b) digital meter (c) fault detection (d) operational chart (e)

soldering iron

99. ……………. is used to melt the soldered components or elements for proper examination

(a) soldering iron (b) operational chart (c) electric tester (d) oscilloscope (e)

troubleshooting

100. The process of finding likely fault in electronics using the appropriate tools is ……….

(a) digital meter (b) troubleshooting (c) iron (d) ore (e) timber

SEE MORE QUESTIONS BELOW!

BASIC TECHNOLOGY PART C

STANDARD OBJECTIVES TEST JSS THREE

(Question Source: Comprehensive Workbook On Basic Technology For Secondary Schools Book

Three, By Oyeyemi R.J.)


1. Isometric drawing the angle used for projection is (a) 30° (b) 45° (c) 60° (d) 70° (e) 90°

2. First angle projection originated from (a) Britain (b) Germany (c) Holland (d) France (e)

America.

3. In Orthographic projection hidden details are represented by (a) Chain lines (b) Short

thin dashes (c) Continuous thick lines (d) Thick wavy lines.

4. In third angle projection the plan is usually placed

(a) Below the side view (b) Above the front elevation (c) Above the side view (d) Below

the front elevation (e) Beside the front elevation.

5. The two principal views used in Orthographic projection are the (a) Front elevation and

the side view (b) End elevation and the side view (c) Front elevation and the plan (d)

Plan and the end elevation. (e) First auxiliary plan and first auxiliary elevation.

6. Which of the following devices convert rotary motion to linear motion (a) Crankshaft (b)

Steering wheel (c) Connecting rod (d) Cylinder block (e) Gearbox.

7. The reciprocating motion of piston is converted into rotary motion by (a) Gear (b) Crank

(c) Belt (d) Linkage (e) Bearing.

8. The device used to transmit motion in one direction only is (a) Clutch (b) Gear (c) Worn

wheel (d) Ratchet (e) Propeller Shaft.

9. The device which connect and disconnects two revolving shaft is called (a) Clutch (b)

Brake (c) Gear Box (d) Axle (e) Piston

10. Rotary motion in core direction can be converted to rotary motion in a perpendicular

direction by the use of (a) Cram shaft (b) Link (c) Ratchet (d) Gear (e) Wheel.

11. Which of the following combination is NOT used for power transmission (a) Belts and

Pulleys (b) Meshing gears (c) Sprocket and chain (d) Variable belt and pulley (e) Belt

and gear.

12. A mechanical device that transmits intermittent motion is the (a) Ratchet (b) Shaft (c)

Gear (d) Brake (e) Clutch

13. The conversion of rotary motion to reciprocating motion is produced in one of the

following devices (a) Screw jack (b) G-Clamp (c) Crankshaft (d) Metalwork vice (e)

Pulley

14. The function of a clutch in any vehicle is to (a) Help the gear move faster (b) Make the

vehicle negotiate a blend (c) Act as a release to change gear easily (d) Enable the vehicle

stop instantly.

15. The purpose of hydraulic fluid in any system is to (a) Increase and transmit the pedal

force (b) Decrease and transmit the pedal force (c) Neutralize the pedal force in

the transmission (d) Maintain a constant transmission system (e) Lubricate the

transmission system

16. The function of a brake is to (a) Control motion (b) Neutralize motion (c) Stabilize

motion (d) Minimize motion (e) Eliminate motion

17. The speed of a vehicle is increased by the (a) Accelerator (b) Road wheel (c) Gear (d)

Force (e) Clutch.


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18. Automobile engine is called heat engine because it

(a) Uses heat energy (b) Converts mechanical energy into heat energy (c) Uses fuel for

its operations (d) Converts heat energy to mechanical energy (e) General heat.

19. Transmission of electric power is always at (a) High frequency (b) High Voltage (c)

Frequencies Lower than 50 Hertz. (d) Frequencies higher than 60 Hertz.

20. A device used in transferring energy from one circuit to another by electromagnetic

induction is called (a) Electric motor (b) Stabilizer (c) Transformer (d) Transducer (e)

Galvanometer

21. In a refrigerator, which of the following is referred to as safety device (a) Thermal element

(b) Evaporator (c) Accumulator (d) Compressor (e) Control Motor.

22. The refrigerator component that circulate the refrigerant throughout the system and that is

also used to raise the pressure of the refrigerant is called (a) Evaporator (b) Condenser (c)

Control (d) Compressor.

23. The refrigerator component that is used to transfer heat away from the high temperature

gases refrigerant and change the gases to liquid refrigerant is called (a) Evaporator (b)

Condenser (c) Control (d) Compressor.

24. The following are the major parts of Air-Conditioner system EXCEPT (a)

Compressor (b) Condenser (c) Evaporator (d) Accumulator (e) Capacitors.

25. The component of the refrigeration system used for storing liquid refrigerant is called (a)

Evaporator (b) Compressor (c) Accumulator (d) Condenser (e) Capacitor.

26. Which of these appliances do not have an electric motor? (a) Electric drilling Machine (b)

Television (c) Blender (d) Electric grinder (e) Electric fan.

27. A generator is a machine which converts (a) Mechanical energy into electrical energy

(b) Electrical energy into mechanical energy (c) Mechanical energy into light energy (d)

Sound energy into electrical energy (e) Heat energy into electrical energy.

28. While roofing with corrugated sheet, nails are best driven (a) At any location on the sheet

(b) At the lowest part of the corrugated (c) At the highest part of the corrugation (d) Only at

joint between two near by sheet

29. The following are woodwork fitting materials except (a) Nails (b) Screws (c) Bolts and

nuts (d) Hinges

30. Which of the following are mainly used for fixing upholstery to wood (a) Panel pins (b)

Oval wire nail (c) French wire nail (d) Tack nails (e) Lost head wire nails.

31. The following are some of the various types of locks that are in common use EXCEPT (a)

Butt locks (b) Mortise lock (c) Desk lock (d) Cylinder latch lock (e) Cut box lock.

32. The following materials can be used as finishes in wood EXCEPT (a) Vanishes (b) Paints

(c) Glue (d) Polish (e) Lacquers.

33. The purpose of wood finishes is to (a) Prevent the wood from warping (b) Soften the wood

(c) Prevent the wood from absorbing water (d) Smoothen the wood (e) Make the wood last

longer.


34. Thick glossy paint can be made more lighter for use by (a) boiling (b) erosion (c) adding

water (d) turpentine.

35. Which of the following machine tool is used for cutting wood into marketable sizes (a)

Chain saw machine (b) Thicknessing machine (c) Wood lathe machine (d) Circular sawing

machine (e) Tenoning machine.

36. One of the following operation can NOT be carried out on the surface planning machine (a)

Rebating (b) Chamfering (c) Bevelling (d) Drilling (e) Tenoning.

37. The machine that is mainly used for planning wood to specific thickness after surface

planning machine has been used is called (a) Band sawing machine (b) Drill press (c)

Wood lathe (d) Thicknessinq machine (e) Surface planning machine.

38. The machine that is mainly used for planning faces and truing edges of sawn wood is called

(a) Circular sawing machine (b) Surface planning machine (c) Thicknessing machine (d)

Drill press (e) Wood lathe

39. Which of the following machine tool is used for cutting various sizes of screws (a) Metal

work sawing machine (b) Metalwork grinding machine (c) Metalwork Drill press (d)

Metalwork lathe machine.

40. One of the following metalwork machine tools is used for cutting soft metal with a hack

saw fixed on the machine (a) Grinding machine (b) Shaping machine (c) Milling machine

(d) Power sawing machine.

41. The machine that is used for sharpening dull or blunt edges of metal cutting tools is called

(a) Sawing machine (b) shaping machine (c) Lathe machine (d) Grinding machine (e)

Milling machine.

42. Which of the following is used in machines to reduce friction

(a) Ball bearings (b) Pedal cranks (c) Wheel axles (d) Steering column (e) Propeller shaft

43. Gear, belts and chain drives are used for (a) Energy conversion (b) Energy transmission (c)

Power conversion (d) Power transmission (e) Weight transfer

44. Which of the following combinations is NOT used for power transmission?

(a) Belts and pulley (b) Light energy (c) Electrical energy (d) Sound energy (e) Nuclear

energy

45. In a belt-driving operation, pulley (A) has a diameter of 30mm at a speed of 4m/s. What is

the speed of pulley (B) if it has a diameter of20mm? (a) 12m/s (b)6m/s (c) 3m/s (d) 2.67m/s

46. Which of the following is used to reduce friction between revolving parts?

(a) Bearing (b) Chain (c) Belt (d) Clutch (e) Sprocket

47. The purpose of applying lubricants to a gear box is to (a) Reduce speed (b) Reduce friction

(c) Increase friction (d) Increase speed (e) Reduce kinetic energy

48. The hotness of a motor vehicle tyre is caused by the (a) Radiation of the sun (b) Heat of the

engine distribution to the tyre (c) Spark plugs (d) Friction between road and tyres (e) As a

result of the gear change

49. In a gearing system if gear (A) with 80 teeths rotates 20 times while gear (B) turns 40

times. How many teeth does gear (B) has? (a) 10 (b) 20 (c) 40 (d)160 (e) 70

50. A device used in transferring energy from one circuit to another by electromagnetic


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induction is called (a) Electric motor (b) Stabilizer (c) Transformer (d) Transducer (e)

Galvanometer

51. Which of the following wood joints is used in flooring boards?

(a) Tongue and grove (b) Dove-tail joint (c) Hanched Mortise and Tenon joint (d) Halving

joint

52. The joint suitable for construction of corners of stool, paneled doors and tables leg

turning is called (a) Bridle joint (b) Lap joint (c) Haunched mortise and tenon joint (d)

Dovetail joint

53. The joint suitable for the construction of drawers and cabinet work is called

(a) Dovetail joint (b) Bridle joint (c) Lap joint (d) Mortise and tenon joint

54. The best joint suitable for wooden floor is

(a) Mortise and Tenon (b) Tongue and groove (e) Butt (d) Bridle (e) Dovetail joint

55. Which of the following can be used for internal and external work?

(a) Casein adhesive (b) Vegetable protein glue (e) Animal glue (d) Epoxy resin (e)

Synthetic resin

56. If the time required for a glue to set is not constant the glue that could be used is

(a) Evostic (b) Epoxy resin (e) Casein adhesive (d) Animal glue (e) Vegetable protein

glue

57. The time taken by mixed glue before it set is called

(a) Glue pot (b) Glue spot(c) life glue (d) Pot life (e) Glue life

58. The glue that is made of skimmed milk which is curdled by the addition of dilute acid is

called (a) Animal glue (b) Casein Adhesive (e) Synthetic Resin Adhesive (d) Contact

Adhesive

59. Which tool is used for cutting Circular shapes an internal curve of metal?

(a) Straight snip (b) Bent snip (e) Tin snip (d) Bench shears (e) Straight shears

60. Which of the following is used for cutting sheet metal (a) Scissors (b) Hack (c) Coping

saw (d) Snip (e) Chisel

61. The instrument used for applying heat and solder when soldering metal is called

(a) Anvil (b) Bit (c) Tong (d) Snip (e) Pliers .

62. The hammering and forming of hot metal into a certain shape is known as (a) Brazing

(b) Forging (c) Riveting (d) Soldering

63. Which of the following is NOT a forging process? (a) Casting (b) Upsetting (c)

Twisting (d) Drawing down (e) Bending

64. Which of the following is NOT one of the ways of joining metal pieces together (a)

Welding (b) Riveting (c) Bolt and Nut (d) Screws (e) Nailing

65. All the following are simple forging found in the school workshop EXCEPT (a) Heart

forge (b ) Anvils (c) Tongs (d) Chisels (e) Vice

66. In order to ensure safely in forging operation all metal pieces should be gripped with the

appropriate (a) Vice (b) Anvil (c) Tong (d) Pliers


67. Building blocks are bonded together using (a) Concrete (b) Mortar (c) Aggregate (d)

Asphalt

68. The flood that acquired a very high velocity and great force capable of moving heavy

objects is called (a) Laminar flow (b) Turbulent flow (c) Parallel flow (d) Angular flow

69. When the aeroplane is to climb or drive, the pilot operates on the (a) Rudder (b)

Elevators (e) Tailwing (d) Alleron

70. The following are some of the major cutting tools used on drilling machine EXCEPT

(a) Twist drill bit (b) Reamer bit (c) Countersink bit (d) Centre bit (e) Chisel bit

71. Which of the following is the hardest cutting tools materials (a) High speed steel (b)

Stellite cutter (e) Tungstem carbide cutters (d) Diamond tipped cutlers

72. The following are the processes of providing surface finishes to metal products EXCEPT

(a) Buffing (b) Scratch and Brushing (c) Enamelling (d) Polishing (e) Lacquering

73. The process of making beautiful markings on metal surface using chemical is called

(a) Buffing (b) Scratch and brushing (c) Spot finishing (d) Copper finishing (e) Lacquering.

74. The process of coating internal parts of tins at soft drinks and caned food products with

another tough metal like silver to prevent rusting or corrosion of metal is called

(a) Enameling (c) Lacquering (c) Spot finishing (d) Buffing (e) Copper finishing.

75. Which one of the metal finishing process is used for painting vehicles bodies in the

production company (A) Lacquering (b) Enamelling (c) Tinning and planting (d) spot

finishing (e) buffing.

75. One of the following metal finishing process is used for coating items such as cooking

pots, pails, metal roofing sheet and electric kettle (A) Enameling (b) tinning and planting.

(d) buffing (e) spot finishing.

77. Which type of door has plywood cover on both sides (A) Batten (b) Caved (c) Flush (d)

Panel (e) Revolving

78. The type of floor that is made by mixing and, gravel and cement together is called

(A) Solid floor (b) suspended floor (c) hallow floor (d) overhead floor (e) aggregate floor

79. The following are different type of floor finishes that are used for surface of floor in a

dwelling house EXCEPT (A) Terazzo finish (b) tile finish (c) carpeted finish (d) painted

finish (e) ceramic finish.

80. The following are internal doors EXCEPT (A) Panel doors (b) flush door (c) French doors

(d) Roller shutter door (e) Louvre door

81. Which type of roof is commonly used for large factory building or warehouse

(A) Hip roof (b) Gable roof (c) Shed roof (d) Monitor roof (e) Butterfly roof.

82. The following are major parts of roof EXCEPT (A) Rafter. (b) Purlin (c) Wall plate (d)

Roofing sheets (e) Lintel

83. The slow movement of air due to small pressure differences is called (A) Breeze (b)

Moisture (c) Hurricane (d) Wind (e) Vapour

84. The following systems are technological application of air EXCEPT (A) ballons (b) Air

craft (c) Vaccum cleaners (d) wind mills (e) Automobiles.

85. Inflammable gases should not be left open so as to avoid (A) gaseous outbreak (b) fire


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outbreak (c) soffocation (d) gas leakage (e) Electrocution

86. The process of removing dissolved gases in water during purification is known as

(A) Clarification (b) Chlorination (c) Disinfections (d) Distillation.

87. The device used to move pipe water through a height is called (A) Pump (b) compressor

(c) Pulley (d) Lift (e) Elevator

88. The best reason for keeping household water tanks on a high position is to

(A) Enable fresh air to reach the water (b) Enable the water to flow to all parts of the house

(c) Keep the water out of reach of rodents (d) Keep the water from disease (e) Prevents the

water from overflowing.

89. Which one of the following is not method of treating water (A) Addition of alum (b)

Addition ammonia (c) Addition of chlorine (d) Evaporation and Condensation (e) Filtration

90. which of the following is not a source of water surface supply (A) (a) Lakes (b) pounds (c)

rivers (d) Seas (e) Springs

91. The following are different ways of getting water from well EXCEPT (A) Rope and

buckets (b) Hands pumps (c) Motorised pumps (d) Rope and bucket with windlass (e)

Electric motors

92. The purpose of overhead water tank in a building is for water (A) Purification (b) intake

(c) treatment (d) distribution (e) Filtration

93. Street main are connected to water authority stop cork using the (A) Connecting pipe

(b) Supply pipe (c) Communication pipe (d) storage pipe

94. The following are some of the components or fittings which are utilized in pipeline system

EXCEPT (a) stop cork (b) gate valve (c) taps (d) sinks (e) Electric motors

95. The following are energy from renewable source EXCEPT (A) Biogas (b) Coal (c) Hydro

(d) Solar (e) Wind

96. The main reason for painting for Biogas digester black is (A) That black surface absorb

solar energy (B) To accelerate the fermentation process (C) That black surfaces withstand

atmosphere condition (D) To protect the digester against rusting.

97. The chamber next to septic tank where savage is decomposed by bacterial action and turn

into liquid is called

(A) Compositing system (b) Chemical Chamber (c) Agua privy chamber (d) Filter tank.

98. The following places are the ideals places of using chemical toilets EXCEPT (A) Buses

(b) Train (c) Buildings (d) in the boats (e) Aircraft

99. The type of waste disposal system whereby faeces are stored in water tight with constant

water level is known as (A) Septic tank (b) Aqua privy (c) Compositing system (d)

Chemical toilets (e) Water closet.

100. Foundation trenches can be excavated by (A) Hand and shovel process (b) Digger and hoe

process (c) Manual and mechanical process (d) Physical and mechanised process (e)

Natural and artificial process.


END OF JUNIOR

SECONDARY

SCHOOL

SEE YOU IN SS 1. P.S.S. If you are sure you will be studying Engineering at the University and

you are not well grounded in Basic Geometrical Constructions, then see the

link below for more details and assistance at:

http://basictechnologymadeeasy.com/blog/ss-1-td-videos/

http://basictechnologymadeeasy.com/blog/ss-1-td-videos/


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