Wood.pdf

MATERIAL AND MANUFACTURING 2 Natural Materials I | Woods Instructors : Akela Alsadiq, Zati Hazera, Noran Kattan, Arwa WOOD CAN BE DESCRIBED AS ? WOOD INTRODUCTION. The Great Thing About Wood Is That It Does Grow On Trees Wood has been used to make products since the earliest recorded time. The ancie...

MATERIAL AND MANUFACTURING 2 Natural Materials I | Woods Instructors : Akela Alsadiq, Zati Hazera, Noran Kattan, Arwa WOOD CAN BE DESCRIBED AS ? WOOD INTRODUCTION. The Great Thing About Wood Is That It Does Grow On Trees Wood has been used to make products since the earliest recorded time. The ancient Egyptians used it for furniture, sculpture, and coffins before 2500 bc. The Greeks at the peak of their empire (700 bc) and the Romans at the peak of theirs (around 0 ad) made elaborate boats, chariots, and weapons of wood, and established the craft of furniture making that is still with us today. More diversity of use appeared in Medieval times, with the use of wood for large- scale building, and mechanisms such as pumps, windmills, even clocks, so that, right up to end of the 17th century, wood was the principal material of engineering. Since then, cast iron, steel, and concrete have displaced it in some of its uses, but timber continues to be used on a massive scale. Wood offers a remarkable combination of properties. The direction of it’s grains formulates it’s most unique features In manufacturing, construction, and as an aesthetical element, it is stiff, strong and tough – as good, per unit weight, as self-propagating material it’s wildly available and values depending on quality and treatments , it is renewable, and the fossil-fuel energy needed to cultivate and harvest it is outweighed by the energy it captures from the sun during growth. It is easily machined, carved and joined, and – when laminated –it can be molded to complex shapes. And it is aesthetically pleasing, warm both in color and feel, and with associations of craftsmanship and quality. MATERIAL ENVIRONMENTAL VALUE Today man is connected with the forest by three links/ the social, the ecological, the raw material. The ecological: sees trees as the golbal air conditionar , a CO2 ’recycling machine’ by photothysis ( 1.6 tones per tonne of wood), a machine for producing oxygen, these forests play an essentail role in the equilibrium of our planet.uncertainity arises from the curretn imbalance. We are actually prdocing more CO2 today than the plant are able to absorb-this leads to greenhouse effect. The consequences of large scale defrostation-as in the Amazon jungelcan be felt far and wide. Defrostation is responsible for proximately 20% of world emissions of greenhouse gases, which contribute to global warming and decline of number of endangerd species. The Raw Material :The forest provides us with wood’ as a raw material, a material that has the special quality of being renewable (renewable in the short term compared with fossil fuels) and recyclable. The transformation and processing of wood consumes little energy and in some cases is self-sufficient. Wood is potentially as much a material as a fuel source. Our forests represent an enormous repository of raw materials. Throughout our planet, they take up roughly 30% of the earth's land surface (4.1 billion out of 12.7 billion hectares of land surface area). If the distribution of the forest is not completely uniform between all countries varying between 1% and 98% of a country (in the case of Guyana, for example), forested areas are actually distributed relatively equally between the North and the South of the planet. The large clumps of forested area include: ex-USSR and North America, which represent 40% of the forested land mass, followed by the Amazon and Africa WOOD TECHNIC AL. The Great Thing About Wood Is That It Does Grow On Trees These organic materials combines to from the plant tissues, the arrangement of the tissues, size, and shape of the cells are chartists of each species. A fiber bundel : orianted axially, is the main configuration that determines the direction of the wood, or it’s ‘grain’. The fibers also run radialiy. Vascualr tissue: which allows the unrefined sap to be transported from the roots to the leaves ( through sapwood) Spare cells: (wood parenchyma) WOOD INTRODUCTION. The Great Thing About Wood Is That It Does Grow On Trees Wood can be classified in 3 main categories : ▪ Hardwood ▪ Softwood ▪ Plywood ( chemical composite ) Each species of tree provides different timber that varies in color, grain pattern, texture, strength, weight, stability, durability, cost and ease of working WOOD IDENTIFIC ATION. Identification Color Texture - coarse, fine, even or uneven Figure -Pattern produced on surface - Type of grain, arrangement/size of cells, color variations Grain direction, size and arrangement of wood fibers Hardness - Resistance of the timber. SOFT WOOD Hardwood/Softwood- does NOT refer to hardness or density of wood. Only length Comes from gymnosperm trees which usually have needles and cones. Medullary rays and tracheids transport water and produce sap. When viewed under a microscope, softwoods have no visible pores because of tracheids Softwoods have a wide range of applications and are found in building components (e.g., windows, doors), furniture, medium-density fiberboard (MDF), paper, Christmas trees, and much more Features: ❑ Most softwoods have a lower density than most hardwoods ❑ Softwood is typically less expensive compared to hardwood ❑ Softwood has a faster rate of growth ❑ softwoods shed their leaves over the year. SOFT WOOD Softwoods Examples: - Pine - Spruce - Hemlock - Fir - Cedar - Redwood - Larch HARD WOOD Comes from angiosperm trees that are not monocots; trees are usually broadleaved. Has vessel elements that transport water throughout the wood; under a microscope, these elements appear as pores. hardwoods are more likely to be found in high-quality furniture, decks, flooring, and construction that needs to last. There are also some woods which are considered to be hardwoods that are not deciduous trees, such as Bamboo and Palm. These plants are scientifically known as monocotyledons but have many of the same characteristics of hardwoods and so are often classified as such. They sometimes fall under the next classification of engineered wood Features: ❑ ❑ ❑ ❑ Most hardwoods have a higher density than most softwoods Hardwood is typically more expensive than softwood. Hardwood has a slower growth rate Hardwoods shed their leaves over a period of time in autumn and winter. HARD WOOD Hard Woods: -Oaks - Ashes - Elms - Maples - Birches - Cherry - Walnut - Beeches - Cottonwoods WOOD DIFFERENCE. 1) Hardwoods tend to have broad leaves, while softwoods tend to have needles and cones. 2) The pores in hardwoods are a lot of what gives hardwood its prominent grain, which is quite different from softwood's light grain. 3) HARDWOODS AND SOFTWOODS ARE BOTH USED FOR MANY OF THE SAME PURPOSES 4) softwoods are cheaper and easier to work with than hardwoods ENGINEERING WOOD Engineered wood does not occur naturally in the environment but instead are manufactured. These boards are generally made with wood which is manipulated to have certain qualities or features. Also known as composite wood, these products are often made from the waste wood of sawmills. Engineered wood is often treated through chemical or a heat process to produce a wood product which can meet certain sizes that would be difficult to achieve from nature. Popular examples of engineered woods include Plywood, Oriented Strand Board, Medium Density Fiber Board, and Composite Board. Wood veneers can also sometimes be classified as engineered wood, since it often needs to be manipulated either through specialized cutting techniques or joining pieces together to achieve a specific size or wood grain patterning. ENGINEERING WOOD WOOD MANUFACTURING Manufacturing wood is different from many other types of manufacturing because it requires specialized equipment and expertise to produce high-quality wooden products. The process starts with cutting down trees in order to make lumber for use as a raw material in the production process Major Manufacturing Stages: 1) cutting stage 2) shaping stage 3) finishing stage WOOD MANUFACTURING Sawing Sawing is one of the most common forms of wood manufacturing. It involves cutting the wood into various shapes and sizes. Sawing can be done by hand, but most often it is done with a sawmill. Sawmills can use a variety of saw blades, including circular saws, bandsaws, and chainsaws, to create custom shapes and sizes for the desired product WOOD MANUFACTURING Planning The purpose of planning is to make the wood smooth and even. This is done by running the wood through a planer, which removes small amounts of wood at a time. Planers can come in different sizes and shapes, depending on the type of product being made. WOOD MANUFACTURING Drilling Drilling is a process where holes are made in the wood. This is usually done with a drill press but can also be done with hand tools. The types of drills used will depend on the type of product being made and the size of the holes needed. WOOD MANUFACTURING Shaping Shaping is the process of forming the wood into the desired shape. This can be done with a variety of tools, such as routers, chisels, and hand planes. The type of tool and the type of wood will determine the type of shape that can be achieved. WOOD MANUFACTURING Sanding Sanding is the process of removing material from the wood by using abrasive materials. This is usually done with sandpaper but can also be done with power tools. Sanding is done to make the wood smooth and can also be used to remove imperfections or stains. WOOD MANUFACTURING Finishing Finishing is the process of applying a protective coating or sealant to the wood. This can be done with varnish, stain, lacquer, oil, or wax. Finishing can be done with a brush, a spray gun, or a power buffer. The type of finish chosen will depend on the type of product being made and the desired look. These are the most common types of wood manufacturing processes. Each of these processes has its own unique characteristics and can be used to create different types of products. Depending on the type of product being made, different combinations of these processes may be used to create the desired outcome. WOOD JOINT. Mechanical Joints : These joints are based on the configuration of two pieces of wood using basic woodworking procedures.and it goes centuries back and formulate cultural facades for craftsmanship and creativity there are thousands of different configuration depending on the type of wood and the number of pieces joined and their weight load direction. up to this day wood joints are considered the strongest method to construct with wood and the most sophisticated and valued artisanship. These joints can be glued and nailed for extra support; wood joints are more suitable for hardwood & softwood. WOOD JOINT. Common Type : Tongue and grove Dado Mortise and tenon Dovetail Rabbet Finger WOOD JOINT. WOOD JOINT. WOOD JOINT. WOOD JOINT. WOOD JOINT. FINISHING TECHNIQUES Coating Penetrative finishes: Oil finishes are used to treat the fibers of the wood to create a natural finish and enhance the grain depth, while adding a protective layer Examples/ tung oil, linseed oil, Danish, cedar oil. Surface Finishes: Add to the top of the wood these finishes options are used as a strong protective layer of external wear and tear to the wood, it is also used to alternate the look or color of the material Examples/ Shellac, Lacquer, Varnish, wax, polyurethane, dye, stain, water based finishes , paint. FINISHING TECHNIQUES FINISHING TECHNIQUES Veneering A thin sheet of unrolled wood from the tree trunk, it’s thickness ranges from about 0.3 to 3 MM, which makes the material hold it’s aesthetical and functional qualities while becoming more easier to work with. To be design and cut to size and inlayed to an engineered woods surface to add the desired look. Some Types/ Raw veneer, laid-up veneer, backed wood veneer, laminated or reconstructed veneer Natural veneers, fine line veneer, rotary cut veneers, slides of veneer. FINISHING TECHNIQUES Veneering A thin sheet of unrolled wood from the tree trunk, it’s thickness ranges from about 0.3 to 3 MM, which makes the material hold it’s aesthetical and functional qualities while becoming more easier to work with. To be design and cut to size and inlayed to an engineered woods surface to add the desired look. Some Types/ Raw veneer, laid-up veneer, backed wood veneer, laminated or reconstructed veneer Natural veneers, fine line veneer, rotary cut veneers, slides of veneer.