2. Wood Historical Introduction: Wood is a natural material. Wood and stone were the first materials that man used. Wood is used to light a fire, to make weapons, to build houses, etc. Some of these things are used today.
3. The Tree’s Trunk Wood Bark: the outer trunk´s part. It is a protector of the trunk. . Medullary Rays: they are cracks from the center outwards . Medulla: the inner trunk´s part. Heartwood: the best quality part. Sapwood: part of the trunk with life. It´s the youngest part of the wood. Its colour is light. It has a lot of sap.
4. Wood Obtaining Wood We can extract wood from a tree that is not too young or too old, it depends on the different species To extract wood we follow these steps: Cut down the trees Transport Clean the branches and the bark Cut the wood Dry it Distribution Life rings let us know tree´s age. The clearest rings belong to spring and the darkest ones belong to autumn.
6. Wood To Cut Trees. It is necessary to plant trees again to have wood in the future. This prevents deforestation.
7. Cleaning the trunks Wood Today the trunks are transported by big lorries. From the beginning the trunks were transported by the rivers ´ flow. Transportation First the trees are cut down and then the branches and the bark are cut.
8. To cut the wood Wood The tools to cut the wood are: traditionally circular saws and today big electrical machines or machines with engines. The trunks go to the sawmill. Here the worker marks the lines to cut the wood. This woodcutter makes planks, boards, beams, etc.
9. The distribution of wood Wood Drying the wood After cutting the wood, It´s necesary to dry in order to evaporate the sap and the water. The wood is stacked to allow air to flow. It is faster with hot air. The cured wood is taken to the factories.
12. Wood Types of wood: Exercise : make a Power Point or an Impress presentation with the different kinds of wood . You must show the main properties and applications of every one. Below you can see an example in Spanish.
14. Wood Wood Derivatives Chipboards: Made with glued and pressed wood shavings. We can paste plastic or natural wood sheets together to get a best finish quality. Fiber Boards: We can get them from wood fibers pressed together by high pressure and glued by synthetic resin (DM) or natural resin (tablex).