Woods2
- 2. TREES, A LIVING RESOURCE Wood is one of the most abundant and versatile natural material on earth. Wood comes from trees. Wood is made up of cellulose grains (fibras). Trees contain other substances such as water, oils, resins, mineral salts... What is sap?It’s a solution of water and nutrients that circulates in the tree from roots to trunk, branches and leaves.
- 3. WOODS GIVE US... HEAT. TOOLS AND WEAPONS. CONSTRUCTION MATERIALS. RELATED PRODUCTS: paper, cardboard…
- 4. PARTS OF A TRUNK 1. BARK (corteza): it is the most external layer of the tree and protects tree from damage (extreme temperatures, bad weather, insects). 2. CAMBIUM (líber): it takes the sap from the roots to the various parts of the tree. 3. SAPWOOD (albura): the youngest part of a trunk, which has a clear colour. 4. HEARTWOOD (duramen): it is the part of a trunk that gives harder and more consistent wood. It is the wood used for making things.
- 5. PARTS OF A TRUNK How old is a tree? tree It’s possible to know how old a tree is thanks to the annual rings are seen when a trunk is cut. The clear rings represent the tree´s growth in spring and the dark ones are related to autumn, when its growth is lower.
- 6. THE PROCESS TO GET SOLID WOOD TO FELL (TALAR): It is carried out in winter. Bark and branches are all removed from the tree and they are used for gardens or like a combustible. TIMBER TRANSPORTATION (TRANSPORTE): To carry timber to sawmill by lorry, train or fluvial/maritime transport. CUTTING UP (CORTE): Timber is cut in different pieces and sizes in the sawmill.
- 7. THE PROCESS TO GET SOLID WOOD DRYING (SECADO): It consists of removing natural moisture from timber. This can be done in two ways: Natural (slower and cheaper) and with kilns or air-dried (quicker but more expensive)
- 8. WOOD PROPERTIES How does it feel?: Color, texture, brightness… Hardness: Can tools, nails, screws...make holes in it? Does it wear or scratch by other objects? Density: It depends on mass and volume. Let us know if it is a heavy or light wood. Moisture content (grado de humedad): Different woods have different mass of water and their properties and durability depend on it. Thermal and electric conductivity: Woods are not a good conductor of heat and electricity. Strength: The ability to resist forces without breaking and bending depends on the type of wood. It´s very good when forces act along the grain (fibra). Renewable.
- 9. TYPES OF WOOD HARDWOOD HAYA ROBLE Deciduous (hoja caduca) trees which drop their leaves in winter and are the typical round top tree shape. WALNUT OAK BEECH SOFTWOOD PINO PINE ABETO FIR Coniferous (coníferas), which are cone bearing evergreen (hoja perenne) trees which generally have the typical Christmas tree triangle shape. Softwoods are cheaper than hardwoods and easier to work. Hardwoods are attractive woods but they are not easy to work.
- 10. MAN MADE WOODS Man-made wood has been made up of bits of wood which originally came from a tree. PLYWOOD CHIPBOARD CONTRACHAPADO AGLOMERADO HARDBOARD TABLEROS DE FIBRA
- 11. WORKING WITH WOOD To make a wood object we must follow the next steps : MEASURE, MARK AND DRAW HOLD CUT AND SAW DRILL PLANE JOIN AND SAND PIECES FINISH
- 12. COMMERCIAL WOODS Natural woods can be sold with different shapes: Thick plank Wood sheet Board Plank Strip Frame