✅3.4 - Wood Flashcards
1
Q
Types of timber (softwood)
A
Scots pine / Parana pine / Spruce / Yellow Cedar / Redwood
2
Q
Types of timber (hardwood)
A
Ash / Beech / Elm / Mahogany / Oak / Teak
3
Q
Description of Scots pine
A
- Straight grained
- Prone to knots
- Pale in colour
- Strong yet easy to work with
- Cheap
- Readily available
4
Q
Uses of Scots pine
A
- Low-cost furniture
- Construction work
- Simple joinery
5
Q
Description of Parana pine
A
- Hard
- Straight grained
- Virtually knot free
- Fairly strong
- Comparatively expensive
- Pale yellow in colour with darker brown streaks
6
Q
Uses of Parana pine
A
- Better quality furniture
- Structural carpentry that is visible (e.g. windows, doors, staircases)
7
Q
Description of Spruce
A
- Creamy-white with small hard knots
- Not very hard wearing
8
Q
Uses of Spruce
A
- Indoor furniture (including bedrooms and kitchens)
9
Q
Description of Yellow cedar
A
- Very pale in colour
- Light in weight yet rigid
10
Q
Uses of Yellow cedar
A
- Furniture
- Boat building
- Veneers
11
Q
Description of Redwood
A
- Relatively strong
- Knotty
- Durable (when treated with a suitable coating/treatment)
- Low cost
12
Q
Description of Ash
A
- Light creamy-brown in colour
- Open-grained
13
Q
Uses of Ash
A
- Sports equipment
- Wooden ladders
- Tools
14
Q
Description of Beech
A
- White in colour
- Close-grained
- Hard
- Strong
- Prone to warping
15
Q
Uses of Beech
A
- Furniture
- Toys
- Tools handles
16
Q
Description of Elm
A
- Light brown
- Open grain
- Tough
- Resists splitting
- Durable in water and outdoor settings
17
Q
Uses of Elm
A
- Indoor/outdoor furniture
18
Q
Description of Mahogany
A
- Rich reddish-brown colour
- Strong
- Durable
- Interlocking grain
19
Q
Uses of Mahogany
A
- Good quality furniture
20
Q
Description of Oak
A
- Light brown colour
- Strong
- Tough
- Open-grained
- Corrodes steel screws and fittings
- Reacts with certain adhesives
21
Q
Uses of Oak
A
- High quality furniture
- Interior woodwork
22
Q
Timber
A
Wood that is used in the manufacture of an artefact (e.g. furniture, houses, boats) and is processed and turned into a form that can be easily used (e.g. planks)
23
Q
Hardwood
A
Wood that comes from broad-leaved trees, such as oak, beech and ash, that lose their leaves in autumn
24
Q
What are the two categories of natural timber?
A
Hardwood and softwood
25
Softwood
Wood that comes from fast-growing evergreen trees with cones and needles
26
Seasoning
The process of drying out timber so that it becomes strong and will not change its shape over time
27
Manufactured board
Boards that are made in specific sizes with specific properties.
28
How is manufactured board made?
By joining or compressing small pieces of wood, often off cuts and waste from timber processing
29
Six main types of manufactured boards
Blockboard / Chipboard / Hardboard / Medium Density Fibreboard (MDF) / Plywood
30
How is blockboard made?
Manufactured with a central core of softwood strips bonded together with adhesive and covered with a sheet of plywood on either side, and then often a finishing veneer
31
How is chipboard made?
Made up of small chips of wood bonded together with resin and compressed to form sheets
32
How is hardboard made?
Made from pulped wood fibres that are pressurised until the fibres bond together to produce a board that is smooth on one side and rough on the other
33
How is MDF made?
Made up from very fine wood dust and resin pressed into a board
34
How is plywood made?
Made from veneers of timber with the grain of each layer being at right angles to the layers either side of it, then the layers are bonded together by resin and pressure
35
About chipboard
- Not as strong as plywood and blockboard
- Does not come in sheets sizes as thick as plywood and blockboard
- Comparatively cheaper
- Often used in furniture for use indoors
- Covered in a planting coating/veneer for a more aesthetically appealing timber
36
About hardboard
- Not as strong as other boards
- Typically used in non-structural situations (e.g. the back of cupboards)
37
About MDF
- Can be worked, shaped, machined easily
- Has considerably more strength than hardboard, due to the use of a resin as a bonding agent
- Used in many applications indoors
- Can be easily finished with veneers/paint
38
About plywood
- Numerous types of plywoods are available (often referred to as grades)
- They are all manufactured differently and designed for different purposes
39
Types of plywood
- Boil resistant plywood
- Flexible (flexi) plywood (typically three layers thick with a very thin middle layer)
- Interior plywood
- Laser plywood (non-toxic adhesive for use with laser cutters)
- Marine plywood (moisture resistant)
- Weather and boil proof plywood
40
Advantages of working with manufactured boards instead of natural timber
- Available in large sizes as well as standard sizes and thicknesses
- Boards are designed for specific purposes (have specific properties)
- Elements of waste from processing timber are often used (environmentally sympathetic)
- Uniform with less imperfections (when worked with you are assured that they are not likely to fail)
- Boards do not split like natural timber does
- Available in ready finished formats (with veneers/plastic coatings pre-applied)
41
Veneer
A thin layer of a substance (often timber) that is applied as a surface coating to something, often to increase the aesthetic appeal of the underlying material
42
Warping
The distortion/twisting that can occur to timber, often as a result of poor storage, poor seasoning or natural defect
43
How planks can be cut from the tree to get different properties
- Rift sawn
- Quarter sawn
- Plain sawn
The closer together the wood grains (grain structure) are, the stronger and denser (heavier) the planks are and vice versa
44
Why is timber seasoned?
So that the wood can remain strong and true when used - if not seasoned, the wood can change shape and its properties as it dries out
45
How is seasoned timber kept in perfect condition?
It should ideally be stored somewhere with a controlled environment, meaning that it should be kept somewhere that is at a constant temperature and in dry conditions, while the wood is laid flat to avoid warping
46
Steam bending process
Thin layers of timber (veneers) are placed into a steam chamber, where steam is introduced at one end and travels through the chamber, heating the veneer and absorbing into the timber - as the steam cools and condenses, it turns back into water and drains away
47
What happens to the wood after steam bending?
After the wood has been immersed in the steam for a period of time, the veneers removed are flexible and malleable - this change in their properties allows them to be bent into different shapes so that they can then be positioned around a former and clamped/held into place and left to cool for a period of time - upon being unclamped and cooled, they will retain the new shape
48
Laminating process
This process involves using a number of thin laminates of timber and bonding them to each other over a former using adhesives - the curing times and strengths vary from product to product and the layers of laminates need to be held in place
49
Description of PVA (Polyvinyl acetate)
- Commonly used to bond timber as is
- Relatively cheap
- Non-toxic
- Easy to work with
- A white liquid which becomes transparent when dry after application and exposure to air
- Many trade names and types
