6 - Performance characteristics of Woods Flashcards
Types of woods (3)
- Hardwoods
- Softwoods
- Manufactured boards
Types of hardwoods (6)
- Oak
- Ash
- Mahogany
- Teak
- Birch
- Beech
Types of softwoods (5)
- Pine (European redwood)
- Spruce
- Douglas fir
- Larch
- Cedar
Types of manufactured boards
- Plywood
- Marine plywood
- Aeroply
- Flexible plywood
- Chipboard
- MDF
Characteristics/properties of Oak (5)
- Hard
- Tough
- Attractive grain
- Good weather resistance
- Contains tannic acid which will corrode steel screws or fixings
Uses of Oak (5)
- Furniture
- Flooring
- Boat building
- Cladding
- Interior and exterior joinery
Properties/characteristics of Ash (2)
- Tough
- Attractive open grain pattern - making it more flexible
Uses of Ash (4)
- Tool handles
- Ladders
- Sports goods
- Laminating
Properties/characteristics of mahogany (2)
- Can contain interlocking grain - makes it more difficult to work
- Rich dark red colour
Uses of mahogany (3)
- Indoor furniture
- Shop fittings and cabinets
- Veneers commonly used on manufactured boards
Properties of teak (5)
- Hard
- Tough
- Straight grain
- Natural idols resist moisture
- Acids and Alkalis
Uses of teak (3)
- Outdoor furniture
- Laboratory benches
- Traditional boat decks
Properties of Birch (3)
- Hard
- Straight close grained
- Resists warping
Uses of Birch (3)
- Furniture
- Indoor panelling
- Veneers used for Birch-faced plywood construction
Properties/characteristics of beech (5)
- Tough
- Close grained
- Hard
- Available instead and un-steamed
- Does not impart a taste to food
Uses of beech (5)
- Chairs
- Chopping boards
- Tools (mallets)
- Steam-bent laminated furniture
- Turned bowls
Properties/characteristics of pine (3)
- Straight grain
- Knotty
- Can contain resinous knots
Uses of pine (3)
- Constriction work
- Roof beams and timber frame construction
- Interior joinery
Properties of spruce (2)
- Straight grain
- Resistant to splitting
Uses of spruce
• Indoor furniture
Properties of Douglas fir (4)
- Straight or slightly wavy grain
- Few knots
- Stable
- Good resistance to corrosion
Uses of Douglas fir (3)
- Veneers
- Plywood construction
- Joinery and construction work
Properties of Larch (4)
- Hard
- Tough
- Attractive grain pattern fades to silver upon exposure outside
- Good resistance to moisture
Uses of Larch (4)
- Garden Furniture
- Cladding
- Decking
- Fencing
Properties of Cedar (5)
- Straight grain
- Can corrode ferrous metals due to acidic nature
- Low density
- Good sounds damping
- Good resistance to moisture
Uses of cedar (5)
- Exterior cladding
- Sheds
- Greenhouses
- Beehives
- Interior planning
Properties/characteristics of plywood (3)
- Good strength in all directions
- No grain weakness
- Odd number of layers
Uses of plywood (4)
- Structural work
- Desk tops
- Indoor furniture
- Floorboards
Properties/characteristics of marine plywood (2)
- Resistant to moisture - as it is constructed by gap- and void-free and uses specialist water and boil proof (WBP) glue
- Higher quality marine plywood is also resistant to fungal attack
Uses of marine plywood (2)
- Boat dashboards
- Boat lockers and panelling
Properties/characteristics of aeroply (4)
- Plywood Made from high-quality timber such as Birch
- Available in very thin sheets
- Lightweight
- Easy to bend around a support frame
Uses of aeroply (4)
- Gliders
- Laminated Furniture
- Laser cut projects
- Jewellery items
Properties/characteristics of flexible plywood (2)
- Odd number of layers glued together with two outer layers made from open grained timber which allows the sheet to flex
- Bent and clued around a former to achieve a solid shape
Uses of flexible plywood (2)
- Laminated Furniture
- Curved panels
Properties/characteristics of chipboard
Wood chips compressed with a resin such as urea formaldehyde
Uses of chipboard
- soften veneered or covered with polymer laminate
- Kitchen worktops and units
- Shelving and flat-pack Furniture
Properties/characteristics of MDF (2)
- MDF is compressed wood fibres although sometimes urea formaldehyde is added as an additional resin
- Two smooth faces available in either standard grade or veneered with a layer of timber
Uses of MDF (2)
- Model or mould making
- Furniture items e.g bookcases, cabinets and desks
Wood stock forms (4)
- Rough sawn
- Plain squared edge
- Planed all round
- Natural wood
Rough sawn - wood stock form (2)
- The wood comes direct from seasoning and has rough surfaces produced during initial conversion
- Rough-sawn wood will have normal sizes rather than accurate finishes and is the cheapest stock form to buy
Planed square edge (PSE) - wood stock form (2)
- Wood has only one edge that is planted accurately; the rest are rough sawn
- Planning removes about 3mm from the original nominal size
Planed all round (PAR) - wood stock form (2)
- Wood has sides and edges that are all planed square, straight and level, leaving a smooth finish, and is ready to use
- The PAR board is about 3mm smaller all round than the original rough-sawn nominal size and is the most expensive stock form to buy
Natural wood - wood stock form (3)
- Natural wood comes from trees and is available only at the maximum width of the tree
- To produce a wide desktop, natural wood planks need to be joined together
- Planks should be joined with the end grain going in opposite direction to minimise distortion
Manufactured boards (2)
- These are man-made and produced in large sheets, typically 1220mm x 2440mm
- Wide surfaces can be produced from one sheet without the neeed for joining processes
Characteristics of wood (3)
• Strong in along the grain and weaker across the grain
- They are converted from the tree into useable pieces and then seasoned to remove excess moisture (80-90 per cent)
- Is seasoned to help prevent defects such as twisting, warping, cracks, cupping or bowing
How can you reduce the time it takes to season wood?
Trees should be felled in winter when they grow less, have less sap and therefore contain the least moisture
Air seasoning (5)
- Is traditional and inexpensive
- Wood is stacked in a shelter outside, protected from rain
- Air circulates between the planks too remove excess moisture
- Its a slow,process, taking up to one year
- The wood is used for outdoor products
Kiln seasoning
- Is expensive, using controlled temperature and humidity levels
- The wood is stacked on trolleys
- It is initially steamy in the kiln then becomes hotter and drier
- It is a quick process, taking up to a few week
- Wood is used for indoor products
Benefits of seasoning wood (4)
- Gives greater immunity from decay and increased resistance to rot
- Increases strength and stability
- Helps preservatives to penetrate
- Makes Wood less corrosive to metals
