PRIMARY NEEDS HEALTH FEEDING CLOTHING HOUSING

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1 .TECHNOLOGICAL PROCESSES. 1. Technology in response to human needs Technology is a body of knowledge used to create tools, develop skills, and extract or collect materials. It is also the application of science (the combination of the scientific method and material) to meet an objective or solve a problem. Primary needs allow survival: PRIMARY NEEDS HEALTH FEEDING CLOTHING HOUSING Secondary needs increase satisfaction and well-being: SECONDARY NEEDS WORK COMMUNICATION TRANSPORT CULTURE AND ENTERTAINMENT SECURITY 1

2 2. Technology, Science and Socity Differences between science and technology Technology Science Solve problems. Generates curiosity. Create a new reality. Explain and predict reality. The technological method explores The method of scientific work establishes a alternatives and concretes solutions. hypothesis. Obtain artificial products. Make laws, principles, theories, theorems. Technology aims to develop products to meet human needs based on scientific and technical knowledge. BENEFITS Increased production. Reducing the labor. Better quality of life. INCONVENIENCES Air pollution. Abusive use of natural resources. Hazardous materials. Excess waste pollutants. 3. Technological activity and products Process of creating technology products Invention Innovation Materials and tools Planning and organization of work Types of products Crafts Industrial products Major works Made in small installations. A single person perform all operations. Few parts that do not need a complicated assembly. Large facilities. Manufactured in large quantities. Production of many identical products. Construction of buildings and civil engineering. Large number of professionals. Different materials (brick, cement, sand, steel, wood, etc.) 2

3 4. Technological evolution Paleolithic: It is characterized by the use of stone in the manufacture of items for survival. Neolithic: It is still used stone as the main material. Wheel appears. Age of metals: comprises three periods depending on the metal used: the Copper Age, Bronze Age and Iron Age Old Age: A great technological advancement in civilizations like those of Egypt, Greece and Rome is generated. Middle Ages: Occurs great technological and scientific advances. Modern Age: Scientific revolution leading to the creation of objects that have been transcendent for progress develops. Contemporary Age: It begins in the industrial revolution and reaches our days. It consists on a new organization of work. 5. Technological process: The technological process consists in five important steps: 1. Need: detect a problem or need; define the problem. 2. Idea: investigate ideas. 3. Develop the idea: specify the solution 4. Construction: planning and building 5. Check 6. Analysis of objects Descriptive analysis: the study of the shape and dimensions of the object, its constituent parts, materials used, types of joints. Functional analysis: what is it the object, how it works, what options it offers, how it is used, if it meets safety standards. Socioeconomic analysis: satisfying need, where it is purchased, price, problems that can cause to the environment, when it was invented. Comparative analysis: a study of the advantages and disadvantages comparing objects with the same purpose. 3

4 TECHNICAL APPLICATION MATERIALS: WOOD AND WOOD PRODUCTS: 1. How are materials obtained? EXTRACTION Raw material: material resources used for the production of materials. Minerals and rocks are mined in quarries, mines or wells (granite, silver). The materials of plant or animal origin are collected after planting or breeding (silk or wood). TRANSFORMATION The raw materials are subjected to physical or chemical processes to get materials for technical use. Examples: metals from minerals in the metallurgical industries; plastics from oil in petrochemical industries. ELABORATION Once processed, the materials come in various commercial forms (strips of wood, cotton, sheet metal). With these, different technological products are made. RECYCLING Many times, the materials from Discarded products can be recovered for use as feedstock in the production of new materials. 2. Types of materials: Materials Classification CERAMIC AND STONED MATERIALS Are obtained from rock, sands or clays. Examples: natural stone (granite, slate); construction materials (cement); ceramic (porcelain); glasses. ORGANIC MATERIALS Derived from plant or animal parts. Examples: wood and wood products (paper, cardboard); leather; cork; cotton fabrics. 4

5 METALS Are obtained after separating them from the metallic minerals that contain them. The most important is steel, but also important are aluminum, copper, brass and bronze. SYNTHETIC OR PLASTIC MATERIALS They are chemically combined substances derived primarily from petroleum or natural gas. Examples: Polyethylene, PVC, acrylic, polyurethane, fibers and synthetic fabrics (nylon, lycra). 3. The properties of materials: HARDNESS Resistance presented by materials to be scratched, cut or punctured. The metals are harder than wood or plastic. RESISTANCE TO EXTERNAL FORCES Capacity of a material to support weight or pressures without breaking. The steel is more resistant than the aluminium or the wood. TENACITY OR FRAGILITY Aptitude to absorb blows or impacts without breaking. The metals or the wood are in the habit of being tenacious (they do not break easily), whereas the glass and the ceramics are very fragile. ELASTICITY OR PLASTICITY Capacity of a material to recover the aspect when it stops the force that deforms it. If it recovers its shape is named elastic, in opposite, plastic. If it suffers almost no deformation, it is rigid. THERMAL AND ELECTRICAL CONDUCTIVITY To allow or to block the way of the heat or of the electrical current across a material. The metals are good drivers and the plastic ones are insulating. CHEMICAL STABILITY Capacity of a material to resist the chemical action of the oxygen of the air (oxidation) or of the humidity (corrosion) or of other aggressive substances (acids, solvents). 5

6 4. Working with materials: PROCEDURE FOR THE UTILIZATION OF THE MATERIALS Fit the dimensions. Draw the pieces from the edges and one from each other as close as posible. Cut the pieces carefully. Keep and take advantage of the cuts. Recover chunks of material from previous works. Classify and arrange all the materials. SAFETY PROCEDURE IN THE WORKSHOP Keep the tools arranged. Hold the pieces with firmness. Clean the tools once used. Put attention when using the tools. Use protection elements (gloves, glasses). Use the tools with correction. 5. Wood properties and applications: PRODUCTION OF PAPER AND PAPERBOARD CONSTRUCTION MANUFACTURE OF OBJECTS 6

7 GETTING WOOD BOARDS DEBARKING SHREDDING DRYING WOOD APPLICATIONS FUEL PRODUCTION OF PAPER AND PAPERBOARD CONSTRUCTION MANUFACTURE OF OBJECTS BUILDINGS, SHIPS, DOORS, WINDOWS, FLOORS, ETC FURNITURE, HOUSEHOLD UTENSILS, MUSICAL INSTRUMENTS, ETC The paper industry Reduce wood into tiny cellulose fibers up to forming a pasta named pulp. Substanc es (coloring) are added to the pulp to achieve desired properties The pulp obtained is pressed to get a thin sheet of paper. Paper is stored for later sale. 7

8 6. Types of Wood and Wood derivatives: Natural Wood: solid wood obtained from sawing logs. According to the source tree, can be classified into CONIFERS HARDWOOD TROPICAL They come from evergreens They are extracted from They are hardwood from (pine, fir, cypress, cedar) that deciduous (oak, beech, rainforests (mahogany, provide light, soft and easy to walnut, poplar, chestnut, ebony, teak, samba, raft, work with wood. olive, ash) which often give ocume, sapele). The heavy, hard and sometimes difficult to work with wood. properties of the wood are more diverse, there are hard or soft, heavy or light, Used in construction structures, interior or exterior carpentry, rustic furnishings. Used in interior carpentry, furniture, tool handles, housewares, shipbuilding, sticks, matches. different colors and veining. Used in interior carpentry, furniture, packaging, DIY Parts, carvings and frames. Woods Transformed have some advantages over natural: they can be prepared in large boards, better use of wood, rot and deform less, are cheaper. PLYWOODS Plywood is a board made from thin sheets of wood glued transversely to the fibers on each other with synthetic resins under strong pressure and heat. Having crossed veins deform less and have equal strength in both directions. They can be deformed to obtain curved pieces. AGGLOMERATES BOARDS AND FIBER MOLDINGS Boards are manufactured with small wood chips glued together under pressure and without further finishing. Fiber board is constructed from woods that have been reduced to fibers and subsequently reconstructed by applying pressure and glue. It is the cheapest board. Its use is not recommended in wet conditions, as absorbed humidity, it swells and does not recover with drying. They break easily and do not support unions with nails and screws. Deforms less and resist moisture better than agglomerates. They can be worked similarly to the natural wood. You can paint, varnish or lacquer it. EDGE-GLUED PANELS They are realized joining strips of natural wood for its singing with the help of resins. It looks like a natural wood board. They have the same properties of wood with which they are made. They work like natural wood. 8

9 Commercial forms: 7. Woodworking: BOARD SLAT MOLDING 7. The measurements are transferred from the edges or reference lines using the ruler or meter, and marked with pencil. MARKING AND TRACING To allow the saw cut it is recommended to left two or three millimeters of separation between the different pieces. The layout square moves on the wood to trace perpendicular lines to the same line. The handsaw is used to cut large pieces of wood and when the court does not require high precision. The backsaw is a tool similar to the handsaw, differing from it by bringing a metal reinforcement called rib on top of the sheet. SAW TOOLS The backsaw is used to make straight, accurate cuts. The start of the court should be slow, making sure it is aligned. To cut slats or moldings cutting guides should be used, which direct the movement of the backsaw with great precision. MAKING HOLES Choose the right bit and set it in the drill. Hand drill: Place he tip of the drill on the center of the hole Press vertically Turn the handle 9

10 WOOD FILE: LOWER THE WOOD TO ACHIEVE THE DESIRED SHAPE. FILE TOOLS SANDPAPER: THE EDGES ARE SHARPENED, ELIMINATING CHIPS OR DEFECTS. TO FACILITATE THE WORK, IT IS MOUNTED ON A WOODEN BLOCK. 8. Work with wood: joints and finishes NAILED AND GLUED JOINS (PERMANENT JOINS) Before joining together the pieces, start nailing at the edge of one of them, without allowing it to pass through. White glue is applied on one of the pieces. One piece rests on the other to finish nailing. Then the excess glue is removed. SCREW CONNECTIONS (DISMOUNTABLE JOINS) Place the higes on the pieces together and mark the position of the holes. In the market there are a variety of hinges, depending on the pieces to join. A small hole is made on the marks using the auger or drill. After THAT, the HIGES are placed and pieces ARE screwed. Paints and varnishes are extended with paintbrushes. It should be done in ventilated places and gloves should be used. APPLYING PAINT AND VARNISH The paint is applied with a lightly loaded brush in the same direction. For consistent color, several layers are needed. Pieces should be stored dry. The brushes are cleaned with water or solvent, depending on the paint used and stored dry. 10

11 9. Environmental impact of the exploitation and use of wood ENVIRONMENTAL IMPACT OF THE EXPLOITATION AND USE OF WOOD Deforestation of primary or virgin forest More than a third of timber world trade comes from illegal logging. Pollution of water and air Produced by the processing industry of wood, especially paper, employing highly polluting chemicals such as chlorine. RESPONSIBLE CONSUMPTION OF WOOD AND PAPER Acquire certified wood products Use artificial boards Recycle and use recycled paper 11