Industrial Technology, Timber Products and Furniture Study Notes Perry Tappenden Materials Terminology associated with the timber industry comes in many forms; it is used to address other workers, to give a quick response to a question or to make statements shorter and to not go into extensive detail. Examples of certain timber terminology includes; a Crook: Distortion of a piece of lumber, Header: a structural member located between the stud joint or rafter. These are a few instances of terminology as there are many more than this.
Timber recovery and conversion is when timber is collected either from deposits or from land and sawn into newer sheets of wood, or burned and used for something else such as firewood, this practice is commonly sought after. When wood is converted it can also be broken down into chips and remade into sheets of ply for use thereafter. * Live Sawing: This gives the most timber from the log; it’s the most simple and cheapest way to cut the log into boards. Timber cut in this method may shrink or warp unevenly.
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This timber is suitable for construction work, fences and crates * Quarter sawing: The log is quartered lengthwise, resulting in wedges with a right angle ending at approximately the centre of each log. The resulting boards are called quarter sawn. * Back sawing: Takes high quality timber from faulty logs. It allows for the faulty parts to be cut around with little waste. Back sawing is used for floor and ceiling joints as there is more strength in the direction of the growth rings. Flitches and Burls are deformities on the outside of timber, it’s found on the outgrowth on a tree trunk. Flitches are slices of veneer form a tree trunk and are kept in the order of which they were sawn. * Stability is the limit to which timber can re shaped and formed. If timber is stable then it would have been seasoned and therefore maintains its shape without curling. * Seasoning is the process in which moisture is dried out from the cell walls and cell cavities of the wood. Air seasoning is a natural drying method which takes ither a few days or a few weeks in which timber is stacked in well ventilated stacks out in the open. Kiln seasoning is an artificial drying method in which timber is placed in large drying rooms in which controlled temperature and humidity circuate around the boards. * Equilibrium Moisture Content (EMC) affects the stability of the timber. As moisture content increases. Timber swells. If moisture content decreases, timber shrinks. Timber should ‘move’ in very minor amounts, so therefore it should be properly seasoned.
Timber selection considerations refers to what to consider when selecting timbers, hardwoods and soft woods may be chosen as they both have different moisture contents and therefore different considerations must be put into place. * Plantation timbers come from artificially planted forest or plantation. Timber gained from plantation comes from fast growing trees used for lumber. * Exotic Timbers are timbers that are rare and hard to come by, the timber is a reddish brown and is prized by woodworkers, it is used in wood turnings, handles and other items, an example of an Exotic wood is Allocasuarina Torulosa or known as Forest Oak. Recycling/Reusing Timber is the process of salvaging timber products from old buildings, bridges and wharfs, the timber is then taken to a mill where all metal objects are removed and the the timber is re-sawn and sold to consumers usually as flooring, beams or decking. * ‘Green’ Timbers are wood products that have recently cut and have therefore not had an opportunity to season by evaporation of the internal moisture. The term applies to wood such as firewood lumber. * Economical Usage/ Waste Minimisation revolves around how to control timber wastage.
Scrap timber can be reused in other projects where necessary and therefore saves time and money from buying more timber for other uses. Waste minimisation is how to control timber wastage in order to save money. Waste can be controlled with a waste management plan in which 10% is added to timber to be cut to allow for an affordable amount of waste. * Environmental Issues/Pollution that concern timber production is dust, air emissions and odours and hazard materials including chemicals. Pollution can arise from these things so therefore care should be taken. Another environmental issue is deforestation. Sustainability is about how long a timber will last. Depending on what the desired project is, will reflect that will be selected. A wood such as pine is sustainable but will not last over years like hardwood will. Sustainable timber will have a higher price, but will last longer than most other timbers that are not as sustainable. * OHS Issues regarding timber selection are affected by the type of timber that is chosen. For example if a hardwood is chosen it must be taken into consideration that it is heavy durable and therefore feet protection must be worn.
Also the machinery must be used with caution as it will work harder against the timber. The right timber must also be selected for the job as certain projects require a specific timber that is suitable, if the wrong timber is used it may have an issue such as not being able to support the weight of itself. Manufactured Board are products that are engineered to precise and specific design purposes. Manufactured board is used in a variety of applications such as home constructions to industrial products.
The resulting boards are very stable and offer greater structural strength than natural wood building materials. • The Construction and Manufacture of manufactured board involves the same hard and soft woods used in normal construction. Scraps and other wood waste can be used to make manufactured wood also. It’s manufactured for practical uses and also for flat pack furniture because of it’s low cost. • Veneers are thin sheets of timber, thinner than 3mm that are glued onto core panels to produce flat panels. Veneer is constructed with a either a rotary lathe, a slicing machine or a half-round lathe.
Using different types of slicing, a different type of grain will appear. • Plywood is manufactured by laminating an odd number of thin sheets of timber, or veneers. The sheets are placed with the grain running along the length of the sheet. The sheet is bonded under heat and pressure with durable, moisture resistant adhesives. When bonding the sheets, the sheets are arranged in a grain direction with the grain at right angles in the alternate layers. • Particleboard is made from the thinnings and trimmings from pine plantations as well as plantation trees.
The wood stock is milled in to coarse flakes which are dried and sprayed with a resin adhesive. The flakes are formed into mats with coarse flakes sandwiched between the fine flakes. A number of these mats are placed in a hot press where they are compressed. The high temperature of the press and the resin forms a strong board that is grainless, that prevents termites and borers. • Fibre Boards are constructed the same way as particleboards, the difference between the two is that the particles are pulped to separate the wood fibres which interlock with each other to create the sheet’s strength.
Fibreboards are available in plain sanded sheets or veneered in a range of cabinet timbers. • Block manufactured boards have a limited application in the furniture industry, The main use is an alternative to thin sheets of particle board or medium density fibreboard for cupboard backs and drawer bottoms. • Lamiboard are produced by bonding thin wood veneers together in a large billet. The resulting product features enhanced mechanical properties and dimensional stability.. Lamiboard is used in many products including rafters, headers, beams, joists, rim boards, studs and columns. OH&S Issues regarding manufactured boards is that some of boards may burn faster than solid timber, they require more energy for their manufacture than solid timber, the adhesives used may be toxic, cutting and working can expose workers to toxic compounds, Some of the manufactured products are more prone to heat warping when used for exterior purposes, exterior use is also not recommended because the boards soak up moisture. • Glues used for manufactured wood include: Urea-formaldehyde resins (most common, most cheap, and not waterproof. Phenol-formaldehyde resins (Yellow/brown, and commonly used for exterior exposure products. ) Melamine-formaldehyde resin (white, heat and water resistant, and often used in exposed surfaces in more costly designs. ) Methylene diphenyl diisocyanate or polyurethane resins (expensive, generally waterproof, and do not contain formaldehyde). Fitting and Allied Materials-Hardware and Fittings • Screws are on of the most commonly used woodwork fittings, they have a single use of joing two or more pieces of wood together depending on the length of the screw.
Screws come in different head types for varying areas of work, The thread on each of the screws differs for the grip on the board as well as width of the board. • Nails are also a commonly used fastener in the timber industry and trades. Nails are used to join together two or more pieces of timber and have many variations. Nails also have many variations for different uses and can be inserted at different angles to strengthen joints. • Nuts & Bolts are used in conjunction with one another to joint together a stack of parts.
The joint piese are helf together with a combination of the threads friction, a stretch of the bolt, and compression of the parts. Nuts & Bolts vary in sizes and shapes to fit to the job necessary, nuts bolts as big as 60mm exist on the Sydney Harbour Bridge. • Knockdown Fittings are items of furniture that have the ability to be taken assembled and disassembled any number of times. The furniture has also been made with many different modifications that the owner can perform themselves. These include changing the position of the shelves or even adding shelves in general.
Transport and storage of this furniture is also made very easy. • Hinges are devices that are secured to a side of a cabinet and attached to a door or other object to allow the door to open and close. Hinges are available in many forms and open to a 180 degree angle. The knuckle of the hinge shows when the door is closed but there are many types of hinges such as concealed hinges that prevent this. • Handles are an attachment to a door that allows an operator to open and close the door. Hinges are constantly changing and are manufactured by several manufactures. Handles are made out of plastic, metal and even wood.
They are a D shape and are screwed onto the door frame. • Knobs are similar to handles in which they allow an operator to open and close a door, they might be favoured or disregarded over a handle. Knobs also come in variations of wood, metal and plastic. Like handles they can be used on doors or drawers. • Staples are used by upholsters for fastening fabric to the wooden frames of covered furniture. Staples can be applies with a staple gun or a pneumatic tacker. Staples can also be used in the assembly of light frames and furniture components as an alternative to nailing and are applied with an air tacker. Drawer Runners are devices that are secured to the interior of a drawer and allow for a smooth operation of the drawer and will last a long life. Some draw runners do not allow the drawer to extend to it’s full depth, however, fully extending drawers have an extra telescopic extension which allows the drawer to extend for it’s full depth. • Table Clips are used to attach solid timber tops to tables and other items of furniture, to achieve this result, a groove is cut in the inside faces of the table and the table clip, an S shaped piece, is slotted into the groove and the opposite side is screwed into the top of the table. Latches are a component that allow for two surfaces to connect that also allows for regular separation. Latches are usually used on large doors or windows. They can be made from plastic or from metal and can be secured with a padlock. Latches can also be places on the inside or the outside of a door depending on the levels of security needed. • Catches are a component that is attached to a door and consists of two separate parts, a striker and retainer. Catches can join together via a ball with springs, a magnetic strip on the striker and retainer, or a roller that separates and rolls onto the other.
They keep doors firmly closed, yet are still easy to open. • Shelf Hangers are small shelf supports that are available for various applications. Three commonly used shelf hangers are plug in which simply plug into a drilled hole and are made from plastic. Sleeve mounted which is slim mount that fits into a metal sleeve that is first inserted into the hole. Strip mounted supports fit into holes or slots in plastic or aluminium strips which are knocked into grooves that are cut into the wood side piece. Additional Materials Applied to Timber Based Products Glass as a material can be used in conjunction with timber products. A glass door can be added to a cabinet or a glass centre piece can be applied to a door frame on a small or large cabinet. Glass overall gives a more modern look and prevents dust from getting on the shelves. • Metal is used in conjunction with timber in many ways, handles and knobs can be made from a metal and add a nice overall look to the project. Fasteners are also made from metal. Corner covers can also be applied to timber projects such a chest of drawers or any other box.
These add a vintage or modern look. • Polymers can also collaborate with woodwork, these can be used similarly to metal materials such as handles and fasteners. Also, like glass, a plastic sheet can be used to insert into a door frame. • Upholstery Materials that can be used in conjunction with timber products is fabric sheets, which can be stapled on to cover a certain section. If upholstery is used, It must be fitted properly. Adhesives • PVA or polyvinyl acetate is a white, ready to use, glue. It is not waterproof but will resist bacteria. It has good gap filling qualities, is on stainable, and non flammable. PVA is the most commonly used adhesive in woodworking burt won’t bond a non-porous material surface such as metal to wood. • Epoxy Resin is a two part glue consisting of resin and a hardener or catalyst. They allow assembly time at up to an hour at approximately 20 degrees. It is very fast-setting and contact with the skin should be heavily avoided. It will attach non-porous to porous materials at anytime. • Hot Glue is an adhesive that will glue two surfaces together. The glue is squeezed from a glue gun that heats and melts a stick of glue.
The glue itself will bond together porous materials only as solid objects such as metal or glass will not grip the glue when it hardens. • Urea-Formaldehyde are thermo setting adhesives which are hardened by the addition of a catalyst. The adhesive is widely used in the industry. It takes 2-24 hours to set at room temperature. The glue cannot be softened by heat one it sets. Ventilation or respiratory equipment should be used with this adhesive and contact with the skin should be avoided. • Resorcinol glue is an adhesive that has high strength in both dry and wet conditions.
It is also resistant to high temperatures. It’s main use is to glue timber that requires immediate repair straight away. The glue withstands tropical and sub-zero temperatures as well as salt and fresh water. • Contact Glue is a synthetic rubber based adhesive, It is mostly used to bond plastic laminate to manufactured boards. Adhesive is applied with a spreader which becomes dry in about 10-20 minutes. The two sheets are brought together resulting in an immediate bond. No cramping is necessary, rather rubbing and smoothing with a block of wood. The adhesive is flammable, highly toxic and gives of pungent fumes.
Processes, Tools and Machinery Planning • Sketches are used to help develop ideas, communicate design ideas to others such as the client, factory manager or workshop supervisor. They also help to work out sizes and proportions. Many sketching techniques ar ecarried out in order to communicate through the sketch. • Workshop Drawings are usually of the multi-view type, prepared accurately to scale. Drawing standards are intended to provide consistency in presentation. If a furniture designer prepares a drawing then it should be able to read by all people that follow the same presentation requirements. Material Lists require linear measurements and basic calculations. Timber is sold in metres so therefore all measurements must be counted for and there should be waste allowance which equals to an extra 10% on the final measurement. A materials list should include size of the section, species of timber, type of finish, number of pieces and the lengths required. • Calculations that are included in woodwork require addition, subtraction, multiplication and division. This is necessary when setting out details and working out quantities and costs.
Calculations are applies to the area, surface area, and waste allowances using formulas and equations. • Costing is a major factor in measurements of timber. For costing it must be made certain that all materials needed for the project are listed and also to keep the unit of measurement consistent, this will prevent confusion from the timber seller and fellow furnishers. Preparation of Timber • Dressing timber involves making the timber flat, straight and square, so that it’s ready for a project. Dressing can be done with a professional machine or it can be done manually using hand held power tools.
Dressing timber by yourself ensures that even though timber may have warps or twists they can be compensated for and attended to straight away. • Thicknessing involves using a thicknesser machine to narrow down timber to a desired thickness. The process is by setting the machine to a desired thickness and inserting the wood into the opening where it will be cut down to a thickness that is required. The result will not happen immediately as it will take a while to narrow down the timber. • Face sides of timber need to be well sanded and at the correct measurement.
Due to the face side facing outwards on the project, it is important that it is well sanded, and planed to a correct standard so the project does not look out of shape. • Edges on timber must be square on all sides of timber. This must be checked with a square and must be fixed if the timber is not properly edged. When creating joints, all edges have to be square as a defective edge can throw the whole prohect out of proportion. Manufacturing Individual Components as a Part of a Project • Legs Widening Joints • Dowelled Butt Joints is a simple method of widening to form a solid timber top.
Dowels are positioned at 150-200mm intervals along the length of the boards. The direction of the growth rings shouldbe alternated for when wide boards are joined. Care should be taken because when one of the boards has movement it will react onto the next board. • Tongue and Groove joints are widely used for re-entrant angles. The effect of wood shrinkage is concealed. Each piece has a slot cut all along one edge, and a thin, deep ridge on the opposite edge. The joinging method has been rendered obsolete with the introduction of plywood. The method however is still used in higher-quality flooring. Rebate housing joints is similar to a butt joint , except it has a second contact surface. The second contact surface allows for another set of nails to be hammered into the joint to make for a stronger joint overall. • Groove and Feather is similar to the tongue and groove joint, however, in the opening a wood feather strip is inserted. This allows for an alternative to the tongue and groove joint. • Biscuit joints are a quick and easy way to reinforce butt and mitre joints. The oval shaped biscuits fit into place from a hole made by a biscuit joiner.
Biscuit joints can basically be used wherever dowel or mortice and tenon joints can be used. This includes framing, widening, and leg and rail construction. Framing Joints • Mitre joints involve cutting the flat side of timber at a 90 degree angle. The joint is usually used for the corners of picture frames and decorative furniture mouldings. The angles are cut with a mitre saw. The joints can be joined with dowel, biscuits or can be joined via mitre halving joints. • Halving Joints have half the thickness or width of the material removed from each part, so that when the opposing sides are joined they will be flush with one another.
Corning halving is used for frames. The halving joints themselves can be reinforced with nails and/or glue. • Dowelled are commonly used in frame construction as well as leg and rail construction. Dowels are glued into one piece and the joint is assembled with glue applied to the contact surfaces and the other dowel holes. • Box Pin is also known as a Finger Joint and involves cutting a set of complementary cuts in two pieces of wood, which are then glued. It is stronger than a butt or lap joint and will often form the general overall look of the piece. Mortise and Tenon joints are probably the most common joints used in framing timber joinery and traditional furniture. They have several variations which allow furniture designers to combine creative design with sound construction. The joints themselves can be strengthened with wedges, nails and glue. • Bridle Joints have a third of the thickness of the material removed from the centre of the one part of the joint and from the outsides of the other part. Carcase Joints • Rebate joint is a recess or groove cut into the edge of a piece of timber. Rebate joints.
Rebate joints are stronger than the usual butt joints because they have two contact surfaces which allows for two nails to be inserted if necessary. • Scribed joinery is the technique of shaping the end of a moulding or frame to fit the contours of an abutting member. It is commonly used in skirting and other moulding in a room. Coping is only used for internal corners. All other external corners will be mitred. • Dovetail joints are tapered so that the joint can come out in one direction only. Dovetails cut on one part of the joint fit into sockets cut on the other part.
The shapes left between the sockets are called pins. Hand cut dovetails are always larger than the pins, machine cut dovetails and pins are the same size, except for the smaller outer pins. • Housing joints provide more strength than butt joints and are commonly used where load bearings is an important design factor. Housing joints are used in framing, they come in variations such as through housing, stopped housing, and rebate housing. Construction Techniques • Sawing is the most commonly used technique to cut wood into the shapes and sizes as desired. Sawing can be performed with several cutting devices.
The handheld saw, a drop saw, a band saw and a table saw to only mention a few. Sawing can be dangerous if safe and correct procedures are not carried during operation. • Drilling is also one of the most commonly used techniques in furnishing. It involves a drill bit, powered by a drill to create a hole in the timber to allow a screw, a dowel, or a bolt to enter the hole for many purposes. The drill bits vary in size and length and this will affect the depth and size of the hole. • Edge Treatments for timber include smoothing out the edges with a plane or using sandpaper with a sanding block.
Effects can also be applied to an edge using a router and a router bit that looks good on the project. Other treatments include using a router to make a housing joint. • Nailing and Screwing techniques include collaborations with joints such as mortise and tenon joints to strengthen these. Nails are applied with a hammer or a nail gun and screws are inserted with a power tool or handheld screwdriver. • Sanding is a technique that involves a grainy paper, that slowly scratches away at the wood grains and creates a smooth finish. Sandpaper is sanded on using a cork sanding block.
Varying grains on the paper, make the difference between how much of the grain you want to remove and how smooth the timber will come out. • Scraping is an old technique that allows for an extremely fine finish on timber. Scrapers work best on highly figured woods. A difference between sandpaper and a scraper is that sandpaper can suppress the 3 dimensional look of the wood, but scrapers can restore this. Other Construction Techniques • Turning involves a rectangular prism shaped piece of timber that is spun on a lathe and chisels are applied to the surface which cuts away, eventually creating a cylindrical shaped piece.
Turning is an effective way of creating posts, or details to an overall project. • Carving is a practice that is applied to the surface of timber where a shape, pattern or any other design is chiseled and carved into the timber using various tools. The practice, when done by hand is very difficult as accuracy and precision is at stake and could ruin the entire surface. Professional machines are available which use precise accuracy to cut out the shapes. • Inlaying involves a shape, usually made from veneer being inserted into a depression that is the same shape as the veneer or contrasting coloured timber.
Inlaying can be done by hand but like carving, is a very hard practice. It should be done with an accurate machine. • Marquetry is similar to inlaying except it is made up of more pieces and is much harder process. The results that come from marquetry is decorative patterns, designs and pictures. Thin veneer is also used for this method as it is also easy to sand and shape. • Veneering is an old art of having thin sheets of veneer board covering the outside of timber sides and creating a nice look that appears like it’s a full piece of timber.
Veneer boards are stuck to plywood boards to create a nice finish from the outside. • Parquetry is a similar method to Marquetry except it form simple geometric shapes, forming tiled patterns that would cover the floor. Aside from veneer, other timbers can be used such as oak, walnut, cherry, can be enployed. Even expensive timber such as mahogany can be used. • Laminating is a technique that uses a multi synthetic that is fused in a lamination process. Laminating simulates timber with a photographic applique under a clear plastic layer.
Laminated flooring is most commonly used as this is cheap, more durable than carpet and looks like the floor is made from proper timer. • Bending is a technique that is applied to that is applied to sheets of timber when a bend is necessary, this could be for a ramp or any other similar device. T bend sheets, the boards are steamed and the pores in the timber become soft and allow for it to bent into a curved shape. • Routing is a process for creating a recess into pieces of timber to allow for a housing joint or any other timber to be inserted to create a strong joint.
Routing can also be applied to the edges of timber for corner work that involves joints. Construction Techniques Using Manufactured Boards • Economical Sheet Layout is the process of choosing manufactured boards that have minimal surface defects. Its best to choose the most economical sheets when they are all laid out. Using proper veneer and pine combinations also help with the outcomes of plywood economics. • Cutting Sheet Material can be carried out in a number of ways. Manufactured sheets can be cut out using a table saw or a circular saw. A saw guide helps with a circular saw.
Cutting sheet material is an easy process but still must be carried out responsibly and properly. • Handling Sheet Material should be like handling most other timber in the industry. It should be held close to the body where it is safe and won’t be dropped. If assistance is required for lifting heavy or rigid sheet materials then help should be requested immediately. • Assembly of Components should be carried out with proper joints and with proper components for assembly. Components used for manufactured boards include screws and nails and glue, these are usually joined with butt joints.
Assembly of Components • Test, Fit and Check Joints is a process that must be carried out before proper gluing of a project. The joints should all be joined without glue to be tested if they fit. All joints should then be checked with a square at the corners. If it is not accurate, then some chiseling or filling should be carried out. • Dry Cramp is a technique that should be carried out before gluing. The frame or project should be fitted into the cramp so that when the glue is applied it can quickly be placed into the cramp without a messy job. Use of Cramps is a sometimes difficult procedure but can be made easy when all steps are followed. The cramp should be dry tested as described above and then glued and tightened. When tightening cramps, they should be tightened evenly. Parallel clamp should be placed in the middle to counteract the outer clamps making the board bend upwards. • Testing for Square and Flatness should be carried out using a square on the corners. If the joints are not square, then the cramps should be loosened and the frame or project be readjusted. To check the flatness should be done with the side of a ruler or with a flat piece of timber.
Its best to check the flatness to avoid the frame or timber going in wind. Finishing • Preparation for staining involves the process of setting up the timber with a work table and brush and brushing on the stain to the timber in all the desired areas where necessary. • Staining gives the wood a more professional look and makes the wood look more expensive. • Filling fills in the pores of the timber of open grained or textured timber to provide a smoother surface to build up the finishing material. Oils consist of oil-soluble dyes dissolved in oils such as turpentine. Finishes can range in appearance from a deep, shiny glass-like look to a dull surface which reflects very little light. • Shellac is used for traditional French polishing, It’s a natural resin that is applied with a polishing pad and gradually builds up the body of coating. • Nitro-Cellulose Lacquer is a spray on finish that needs to be thinned down and dries in a few minutes. • Environmental Issues that concern polishing are the fumes that the finishes give off, while not entirely harmful to the human body, these do inhabit the air and could affect the surrounding environment.
Ii would also require a lot of energy to make the finishes also. • Industrial Processes that are associated with finishing is the proper use of PPE, this would include gloves, and possibly a face mask, depending on the users intake of the fumes from the finish. It would also be necessary to work in a well ventilated room to ensure that the fumes to not fill up and enclosed room. Other processes include leaving the timber a good amount of time to dry before another coat is added and to follow all instructions on the finishes container such as application and preparation.