JSS 1 Basic Technology (1st, 2nd & 3rd Term)

Rubber and plastics

Rubber vs. Plastic In the past, people have seen the progress of technology. From the simple usage of wood and cement to the invention of metal, mankind has really made great progress to become what they are today. Along with this progress are some changes to their lifestyle. These changes were brought about by the materials surrounding them, and two materials that revolutionized man’s life today is rubber and plastic. It is quite easy to differentiate between the two. By simply looking at each material, one can immediately tell that a particular thing, or object, is made of rubber and not plastic, or vice versa. The only confusion between the two is when the term polymer is used. Yes, polymer as a term that greatly denotes plastics, but nonetheless, this term also describes the characteristic of rubbers. Although rubber is more of the specific elastomer (a viscous or elastic… Read More »Rubber and plastics

Properties of ceramics and glass

Ceramic Material Characteristics Ceramics and glasses are inorganic, nonmetallic materials consisting of metallic and nonmetallic elements bonded primarily with ionic and covalent bonds. These high strength bonds give rise to the special characteristics of these materials. They occupy a unique place in the spectrum of engineered materials offering many desirable alternatives to the metals and polymers in common usage. General Characteristics of Structural Materials Characteristic Ceramics Metals Polymers Density Low to High Low to High Low Hardness High Medium Low Tensile Strength Low to Medium High Low Compressive Strength High Medium to High Low to Medium Young’s Modulus Medium to High Low to High Low Melting Point High Low to High Low Dimensional Stability High Low to Medium Low Thermal Expansion Low to Medium Medium to High High Thermal Conductivity Medium Medium to High Low Thermal Shock Low Medium to High High Electrical Resistance High Low High Chemical Resistance High… Read More »Properties of ceramics and glass

Metals

Metals – Ferrous and Non Ferrous 1. Metals. Exercise 1: Make a list of all the different metals that you know about. 2. Metals. Two main groups, 1.Ferrous. 2.Non-Ferrous. 3. Metals Ferrous Pure Ferrous Metals Non Ferrous Ferrous Alloys Pure Non Ferrous Metals Copper Non Ferrous Alloys Alum. Brass Bronze Solder Zinc Tin High Speed Steel Copper + Zinc Copper + Tin Lead + Tin Lead Silver High Speed Steel Cutting Tools Gold Mercury Steel Iron Mercury is the only non ferrous metal that is liquid at room temperature. Alloying. 4. Ferrous Metals. Ferrous metals: Ferrous metals are metals that consist mostly of iron and small amounts of other elements. Ferrous metals are prone to rusting if exposed to moisture. Ferrous metals can also be picked up by a magnet. The rusting and magnetic properties in ferrous metals are both down due to the iron. Typical ferrous metals include mild steel, cast iron… Read More »Metals

Properties of metals

Differences and similarities between metals and non-metals Properties: Metals: Non-metals: Strong Brittle Malleable and ductile Brittle React with oxygen to form basic oxides React with oxygen to form acidic oxides Sonorous Dull sound when hit with hammer High melting and boiling points Low melting and boiling points Good conductors of electricity Poor conductors of electricity Good conductors of heat Poor conductors of heat Mainly solids at room temp. Exception mercury – liquid at room temp. Solids, liquids and gases at room.temp. Shiny when polished Dull looking When they form ions, the ions are positive When they form ions, the ions are negative – except hydrogen that forms a positive ion, H+. High density Low density Common Metals and Non-Metals Metals: Non-metals: Calcium Sulphur Potassium Oxygen Lead Chlorine Copper Hydrogen Aluminium Bromine Zinc Nitrogen Lithium Helium Uses of metals and non-metals Metals The uses of metals are related to… Read More »Properties of metals

Properties of materials

What is wood? You often hear people grumbling about money and all kinds of other things that “don’t grow on trees”; the great thing about wood is that it does grow on trees—or, more specifically, in their trunks and branches. Structure of wood Take a tree and peel off the outer “skin” or bark and what you’ll find is two kinds of wood. Closest to the edge there’s a moist, light, living layer called sapwood packed with tubes called xylem that help a tree pipe water and nutrients up from its roots to its leaves; inside the sapwood there’s a much darker, harder, part of the tree called the heartwood, which is dead, where the xylem tubes have blocked up with resins or gums and stopped working. Around the outer edge of the sapwood (and the trunk) is a thin active layer called the cambium where the tree is actually growing outward by a little bit each year,… Read More »Properties of materials

Workshop safety

Rules and Regulations 1) Never work alone in the workshop, work at least in pairs. This is so because in case of industrial/workshop accident the other partner will be a helper (Ecclesiastes 4:9-10) it’s all about Teamwork. 2) Think about what you are doing; think before you start a job and during the entire time you are doing it. Remember that your own personal caution is of more value to you than all the safeguards that can be set up. 3) Know where the main switch is. This stops processes immediately should anything go wrong in the industry. 4) Smoking and carrying matches or naked flames by employees is prohibited in and about the complex except in zone specifically designed for such purposes. Safety section must see that “No smoking” signs are placed in and about their area to warn the employee and visitors. 5) When work is being done… Read More »Workshop safety

Work Shop Safety

Workshop rules and safety considerations Workshop safety is everyone’s responsibility, the following rules have been put in place to ensure the safety of all students and staff. Please read the safety rules carefully before entering the workshop. Workshop rules Student affected by drugs or alcohol are not permittedin the workshop Students with any health problems that may affect workplace safety (e.g. medication, epileptic fits) must report these conditions to the workshop staff Notify the workshop staff of your arrival No food or drink in the workshop Wear the correct protective equipment for the tools you are using – ask if in doubt All chemicals (e.g. glues and paints) must be checked through Chemwatch and with workshop staff before use Immediately notify the workshop supervisor of any faulty or broken equipment Ask how to use the tools safely Make sure your work piece is fixed securely before work commences Keep leads up… Read More »Work Shop Safety

Safety guidelines

Footways or footpaths (including any path along the side of a road) should be used if provided. Where possible, avoid being next to the kerb with your back to the traffic. If you have to step into the road, look both ways first. Always show due care and consideration for others. If there is no footway or footpath, walk on the right-hand side of the road so you can see oncoming traffic. You should take extra care and: be prepared to walk in single file, especially on narrow roads or in poor light keep close to the side of the road It may be safer to cross the road well before a sharp right-hand bend so that oncoming traffic has a better chance of seeing you. Cross back after the bend. Help other road users to see you. Wear or carry something light-coloured, bright or fluorescent in poor daylight… Read More »Safety guidelines

Technology

Technology (“science of craft”, from Greek τέχνη, techne, “art, skill, cunning of hand”; and -λογία, -logia[2]) is the collection of techniques, skills, methods, and processes used in the production of goods or services or in the accomplishment of objectives, such as scientific investigation. Technology can be the knowledge of techniques, processes, and the like, or it can be embedded in machines to allow for operation without detailed knowledge of their workings. The simplest form of technology is the development and use of basic tools. The prehistoric discovery of how to control fire and the later Neolithic Revolution increased the available sources of food, and the invention of the wheel helped humans to travel in and control their environment. Developments in historic times, including the printing press, the telephone, and the Internet, have lessened physical barriers to communication and allowed humans to interact freely on a global scale. The steady progress of military technology has brought weapons of ever-increasing destructive power, from clubs to nuclear weapons. Technology has many effects. It has helped develop more advanced economies (including today’s global economy) and has allowed the rise of a leisure class. Many technological processes produce… Read More »Technology

VOLTAGE, RESISTANCE, INDUCTANCE AND CAPACITANCE CONTENT

VOLTAGE (POTENTIAL DIFFRENCE) Difference between points in electric field: the work done in moving a unit electric charge between two points in an electric field. Electric potential: electric potential expressed in volts. It is measured in volts. The instrument for measurement is a voltmeter. RESISTANCE Resistance is the opposition that a circuit, component, or substance presents to the flow of electricity. Symbol R electricity source of resistance: something that is a source of opposition to the flow of electricity, e.g. a resistor. It is measured in ohms. The instrument for measurement is a ohmmeter INDUCTORS An inductor is a circuit element which has the ability to produce an induced voltage in response to changing current. A device, usually a compact coil, which opposes any change in a circuit current is called an inductor. Inductance is a measure of this ability. When an electric current is passed through… Read More »VOLTAGE, RESISTANCE, INDUCTANCE AND CAPACITANCE CONTENT

BASIC COMPONENTS OF ELECTRIC CIRCUIT

ELECTRIC CIRCUITS Electric circuit can be defined as the path provided for easy flow of electric current. It is for conversion of the electric current into useful purposes such as lighting and heating. Electric circuit is connected or fitted with devices that control and measure the current and energy used in the process. Simple electric circuit BASIC COMPONENTS OF ELECTRIC CIRCUIT THE CELL OR BATTERY The cell or battery is to push the free electrons round the circuit. The work done when one coulomb of charge moves from one point to the other in the conductor is known as potential difference (p.d). It is measured in volt. The instrument used for measuring the potential difference is called the voltmeter (v).The ammeter (A) is used to measure the current flow. Current is represented by the symbol I and it is measured in Amperes. The instrument used for measuring current is… Read More »BASIC COMPONENTS OF ELECTRIC CIRCUIT

MAINTENANCE

DEFINITION OF MAINTENANCE Maintenance in engineering work is defined as the functions that should be carried out every day in order to keep the plant or any engineering equipment in good operating condition. Any breakdown in plant and engineering equipment is the result of inadequate maintenance of equipment. TYPES OF MAINTENANCE Predictive maintenance: This is a method of using modern device to predict, or foresee an impending breakdown in a machine. Preventive maintenance: This is the maintenance carried out on any equipment or machinery even before the need arises. This type of maintenance begins right from the time the equipment is first installed. Corrective maintenance: This is repair work carried out when equipment has broken down. EVALUATION Define maintenance State 3 types of maintenance GENERAL EVALAUTION State three uses of (i) ceramic (ii) rubber Mention 5 woodwork bench fittings WEEKEND ASSIGNMENT Define maintenance State 3 types… Read More »MAINTENANCE

HOLDING DEVICES

In order to work safely and conveniently on any work piece, it needs firmly secured. The devices used for holding these work piece firmly are called holding vices. Holding devices include the following: Vices Clamps Pliers VICES Vices are used for holding objects rigidly in position, so that desired operations can be carried out. Vices are of various sizes, shapes and types. Bench Vice The bench vice is used for all types of heavy work, like filing, chipping and sawing. It is fastened to the bench, near its edge, with bolts and nuts. It has two separate jaws that ensure a firm grip on a work piece. Machine Vice The machine vice is commonly used on drilling, milling and shaping machines. The jaws are left unseparated, so as not to leave any work an already finished surface. Hand Vice The hand vice is used for holding… Read More »HOLDING DEVICES

METAL WORK – HAND TOOL

METAL WORK- HAND TOOL – CUTTING AND DRIVING TOOLS CUTTING TOOLS Cutting tools are tools used for cutting materials by either sawing, filing, chiseling, scraping. Cutting tools include the following: Hacksaw Files Chisel Scraper Hacksaw The hacksaw consists of two parts: the frame and the blade. It is used mainly for cutting metals in the metal workshop. We have (i) the adjustable hacksaw (accommodates different blades) (ii) tubular hacksaw (It has fixed frame) (iii) junior hacksaw (For cutting thin sheets) Files Files are used in forming metals to shape, by the principle of bit-by-bit removal. Files are used for finishing jobs to the required sizes and shapes, after they have been previously cut, using either a chisel or a hacksaw. Files are commonly made from high carbon steel (hardened and tempered). Their length, cross sectionals, shapes, grade, areas of cut and the nature of their cutting teeth, classifies files.… Read More »METAL WORK – HAND TOOL

METAL WORK

METAL WORK- HAND TOOL – MARKING OUT AND MEASURING TOOLS Metal is one of the materials used in technology for construction and fabrication of devices. Metal as a material can be fabricated into various shapes and products. However, to be able to do that, you need appropriate tools. These tools are either hand tools or machine tools. MARKING OUT TOOLS Marking out tools are hand tools used for making lines on metal surfaces, checking alignment, and indicating points or positions on a work piece. Tools for making out in the workshop include: Surface plate Surface table Scriber Odd-leg caliper Divider Punches Try square Box Square Surface plate The surface plate is a precision piece of equipment with a flat surface of high-grade finish, on which work piece are placed for marking out. It is also used for testing the flatness of surfaces. Care of surface Cover the surface after… Read More »METAL WORK

WOODWORK HAND TOOLS

WOODWORK HAND TOOLS – BORING TOOLS, CUTTING TOOLS BORING TOOLS Boring tools are the tools used for making holes on wood. The major tzpes are The brace The bits Gimlet Bradawl THE BRACE: This is a tool used for holding and turning the drill bits or twist drill when drilling hole. There are two types of brace and they are plain brace and ratchet brace. Parts of brace are the head, crank, chuck and ratchet. The head: this is made of hard wood and shaped to fit the hand of the user. It is screwed to a steel sleeve it fits over the the crank rod and runs on the hardened steel balls. The crank: This is a rectangular bent metal rod, it fits into hardwood plastic handle. It moves in circular way called the sweep of the brace. The chuck: the end of the crank is… Read More »WOODWORK HAND TOOLS

REVISION

REVISION ___ is a universal language used for communication among technical people (a) Scaling (b) Technical drawing (c) Sketching (d) Oblique. Technical people include the following except (a) engineers (b) technicians (c) builders and draughtsman (d) lawyer Which of the following is not a drawing instrument (a) set squares (b) French curve (c) microscope (d) pencil The following are the ways of caring for a tee square except (a) use it as a toy gun (b) never use the tee square as a walking stick (c) do not use a pen knife or blade along the edge of the tee square (d) always hang your tee square after use. Set squares are used to draw the following inclined angles except (a) 300 (b) 600 (c) 450 (d) 700 ___ is a universal language used for communication among technical people (a) Scaling (b) Technical drawing (c) Sketching (d) Oblique. Technical people… Read More »REVISION

BUILDING MATERIALS & BUILDING COMPONENTS

FLOORS This is a flat bottom surface in or on any structure. It is a rigid building assembly that divides space horizontally into stories. It forms the bottom of a room. It may consist of joist-supported wood planks or panels, decking or panels supported by wood or steel beams, a slab of stone or concrete on the ground, or a reinforced-concrete slab carried by concrete beams and columns. The floor assembly must support its own dead load plus the live load of occupants, activities, and furnishings. The horizontal supports beneath its top surface—and the vertical supports into which they frame—must be sufficiently large and spaced closely enough to prevent sagging of the assembly Types of floors Solid Floors: These are concrete which may simply be finished with smooth surface or laid with tiles (plastic and linoleum floor tiles), which are not normally laid down in specifications. Suspended Floors: It… Read More »BUILDING MATERIALS & BUILDING COMPONENTS

TYPES OF BUILDINGS & BUILDING MATERIALS

Types of building Bungalow: It is dwelling built in a style developed from that of a form of rural house in India. The original bungalow typically has one story, few rooms, and a maximum of cross drafts, with high ceilings, unusually large window and door openings, and verandas on all sides to shade the rooms from the intense light and tropical heat. A house that is built on one level. One-storey building: A house that has a ground floor and the first floor only. Multi-storey building: A house that has many levels. Skyscrapers: A very tall building. Detached building: A house that is joined with another building at one side. Semi-Detached building: A house that is joined with another building at one side. Duplex: A house that is made up of two apartments. Mansion: A very large house. Terraced houses: These are blocks of building that are constructed together side… Read More »TYPES OF BUILDINGS & BUILDING MATERIALS

WORKBENCH FITTINGS & APPLIANCES

WOODWORK BENCH A woodwork bench is a platform on which the wood workers perform their wood workers activities. The size of the woodwork bench is usually 2.0m by 0.80m by 0.90m. The centre of the woodwork bench is always lower than the edges and this is called WELL. The function of the well is for keeping the tools needed during the woodwork activities. Being lower, tools cannot fall or roll onto the floor or on anyone’s feet WOODWORK BENCH FITTINGS Woodwork bench fittings are the appliances fitted to the workbench before the commencement of any woodwork operation. EVALUATION QUESTIONS Define a workbench Describe and state the function of a well on workbench Define woodwork bench fittings Workbench Fittings VICE BENCH STOP BENCH HOOK G-CLAMP SASH CLAMP F-CLAMP VICE The bench vice is made up of cast iron and possesses a release lever, which allows quick movement… Read More »WORKBENCH FITTINGS & APPLIANCES

JSS 1 Basic Technology (1st, 2nd & 3rd Term)

Install School Portal NG to Home screen!