Timbers Flashcards
Where do timbers come from?
Timbers come from wood cut down from trees. They are a sustainable source of material as trees can be regrown.
What are the properties of softwoods?
-mainly grow in cooler climates
-loose grain
-grow needles
-called conifers or coniferous trees
-evergreen
-fast-growing
-cheaper than hardwoods
-easier to work with
-common building material
-grows tall and straight
-easily cut into planks
Give examples of softwood trees.
-Larch
-Pine
-Spruce
-Redwood
-Douglas fir
-Cedar
What are the three types of timbers?
Softwoods, hardwoods and manufactured boards.
What are the properties of hardwoods?
-tighter grain
-takes a long time to grow
-more expensive than softwoods
-called deciduous trees, some are evergreens
-most evergreens are found in sub/tropical environments such as S. America
-lose their leaves (excl. evergreens)
-usually quite hard
-they are broad leave trees and the seeds are enclosed in the fruit that the tree produces
-generally grow in temperate climates, including the British Isles.
Give examples of hardwoods.
-Ash
-Beech
-Mahogany
-Oak
-Balsa
-Teak
-Birch
What are the properties of manufactured boards?
-available in many thicknesses
-relatively inexpensive so often used instead of real woods
-often covered with a thin layer of real wood which is called a veneer which improves their appearance and properties
-manufactured boards are timber sheets which are produced by gluing wood layers or fibres together
-often made using waste wood
-have been developed mainly for industrial production as they can be made in very large sheets of consistent quality
Give examples of manufactured boards.
-Plywood
-MDF
-Chipboard
-Hardboard
-Blockboard
-Marine plywood
-Aeroply
-Flexible plywood
What are the performance characteristics of timber?
-grain pattern
-grain direction
-surface defects
-warpage
-shrinkage
-splitting
-joining
-forming
-steam bending
-laminating
-machining quality
-decay resistance
-moisture resistance
-toxicity
What are the stock forms of timber?
-rough sawn
-planed square edge (PSE)
-planed all round (PAR)
-natural timber
-manufactured board
-mouldings
-veneers
What are the timber defects?
-splitting
-knots
-decay - dry rot
-woodworm
What types of wood joints are there?
-butt joint
-mortise and tenon joint
-dowel joint
-dovetail joint
-housing joint
-half lap joint
-mitre joint
-comb joint
What is a butt joint?
A simple joint in which the end of one piece of wood is simply butted up against the end of another piece of wood. This joint is the simplest and most basic way to join two pieces of wood, but it is also the weakest, as it relies solely on glue to hold the pieces together.
What is a dowel joint?
A joint in which two pieces of wood are joined together using small, cylindrical wooden pins, known as dowels. To create a dowel joint, holes are drilled in the two pieces of wood to be joined, and the dowels are inserted into these holes. The dowels are then glued in place, creating a strong mechanical connection between the two pieces of wood.
What is a mitre joint?
A joint in which two pieces of wood are cut at an angle and joined together at the corners, creating a seamless and decorative connection. Mitre joints are commonly used in picture frames, crown moulding, and other decorative trim applications.
What is a comb joint?
A joint in which two pieces of wood are joined together by interlocking fingers or tabs cut into the end of each piece. This joint is used to join pieces of wood of the same thickness, and it is often used to make large panels from smaller pieces of wood.
What is a dovetail joint?
A joint in which two pieces of wood are joined together in a interlocking pattern, resembling the shape of a dove’s tail. Dovetail joints are often used in fine woodworking and are prized for their strength and their decorative appeal.
What is a mortise and tenon joint?
A joint in which one piece of wood (the tenon) is inserted into a rectangular or circular cut out (the mortise) in another piece of wood. This joint is one of the strongest and most durable ways to join two pieces of wood and is commonly used in furniture making and cabinetry.
What is a housing joint?
A joint in which a tongue is cut on one piece of wood and a corresponding groove is cut on another piece, allowing the two pieces to interlock. Tongue and groove joints are commonly used in flooring, panelling, and wainscoting applications, as they provide a strong and stable connection that helps to eliminate gaps and minimize movement between the two pieces of wood.
What is a half lap joint?
A joint in which two pieces of wood are overlapped and joined together. This joint is often used in making boxes, chests, and other wooden containers, as well as in making picture frames and other decorative items. There are two main types of lap joints: half-lap joints and cross-lap joints.
What are knock-down fittings?
Knock-down fittings are a type of hardware used in furniture and cabinetry to assemble pieces of wood together without the use of traditional fasteners like nails or screws. Instead, knock-down fittings are designed to interlock and provide a strong, durable joint. These fittings typically consist of metal plates, dowels, or cam locks that are inserted into holes drilled in the wood. The fittings are then tightened to secure the pieces of wood in place. Knock-down fittings are often used in flat-pack furniture and modular cabinetry, as they make it easy to disassemble and reassemble the pieces without damaging them. Knock-down fittings are easy to use and require no special tools, making them a popular choice for DIY furniture and cabinetry projects.
What are modesty blocks?
Modesty blocks are small rigid polymer blocks that are used along with screws to join wood together. Typically they may be used in cupboards and storage units. They are simple to use but does not make a particularly strong joint.
What are barrel nut and bolts?
A barrel nut is a cylindrical nut that has a threaded interior and a smooth exterior. The bolt is a threaded rod that is inserted through holes drilled in the two pieces of material to be joined, with the barrel nut placed inside one of the holes. When the bolt is tightened, the threads engage with the interior of the barrel nut, pulling the two pieces of material together and providing a strong, secure joint.
What are cam-lock connectors?
Cam-lock connectors are a type of fastener used in various applications, including furniture assembly and cabinetry, to quickly and securely join two pieces of material together. A cam-lock connector consists of a cam mechanism, which is typically a cylindrical component with a screw or lever mechanism, and a socket or receptacle that the cam mechanism fits into. The cam mechanism is inserted into the socket and tightened, causing the cam to expand and grip the material being joined. Cam-lock connectors are designed to be easy to use and to provide a strong, secure connection.
