woods
DESCRIPTION
woods and its derivates. Students of the second year.TRANSCRIPT
WOODS
DESIGN AND TECHNOLOGY
2º ESO
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 cellulosecellulose
grains (fibras). Trees contain other substances such
as water, oils, resins, mineral salts...
What is sapsap?It’s a solution of water and nutrients that circulates in the tree from
roots to trunk, branches and leaves.
WOODS GIVE US... HEAT. TOOLS AND
WEAPONS. CONSTRUCTION
MATERIALS. RELATED PRODUCTS:
paper, cardboard…
PARTS OF A TRUNK
1.1. BARK (BARK (cortezacorteza):): it is the most external layer of the tree and protects tree from damage (extreme temperatures, bad weather, insects).
2.2. CAMBIUMCAMBIUM ( (líberlíber): it takes the sap from the roots to the various parts of the tree.
3.3. SAPWOOD (SAPWOOD (alburaalbura): ): the youngest part of a trunk, which has a clear colour.
4.4. HEARTWOOD (duramen):HEARTWOOD (duramen): it is the part of a trunk that gives harder and more consistent wood. It is the wood used for making things.
PARTS OF A TRUNKHow old is a treeHow old is a 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.
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.
THE PROCESS TO GET SOLID WOOD
DRYING (SECADO): It consists of removing natural moisture from timber. This can be done in two ways:
NNaturalatural (slower and cheaper) and with kilns orkilns or air-driedair-dried (quicker but more expensive)
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.
TYPES OF WOODROBLE
HAYA
PINO ABETO
HARDWOODHARDWOOD
Deciduous (hoja caduca) trees which drop their leaves in winter and are the typical round top tree shape.
SOFTWOODSOFTWOOD
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.
PINE
OAKWALNUT
BEECH
FIR
MAN MADE WOODSMan-made wood has been made up of bits of
wood which originally came from a tree.
CHIPBOARD
AGLOMERADO
PLYWOOD
CONTRACHAPADO
HARDBOARD
TABLEROS DE FIBRA
WORKING WITH WOODTo make a wood object we must follow the next steps :
MEASURE, MARK AND DRAW
CUTTING AND SAWING
DRILLING
PLANNIG AND SANDING
JOINING PIECES
FINISHES
FORMAS COMERCIALES
La madera natural se comercializa de diferentes formas:
TABLÓN CHAPALISTÓN
TABLATABLERO MOLDURA