WOODS

Question 1

What direction is wood strongest?

Answer 1

the direction of the grain

Question 2

What are the two main forms of seasoning?

Answer 2

1. air seasoning
2. kiln seasonin

Question 3

What is air seasoning?

Answer 3

A traditional, inexpensive method, which involve stacking the wood under a shelter, protected from the rain. Air circulates between the planks to slowly remove the excess moisture.

Question 4

What is air-seasoned wood used for?

Answer 4

outdoor wooden products because it seasoned to the same moisture content as its surrounding and therefore the wood is less prone to defects.

Question 5

What is kiln seasnoning?

Answer 5

A more expensive but controlled method, which is very quick and can take just a few weeks. Planks are stacked onto trolleys and placed in the kiln where both temperature and humidity is controlled. Initially, the kiln atmosphere is very steamy but this is gradually changed to become hotter and drier.

Question 6

What products are kiln seasoned?

Answer 6

indoor products such as furniture will use kiln-seasoned wood because it has been seasoned to meet indoor conditions and will have a lower moisture content than air-dried wood.

Question 7

What happens if you put an unseasoned plank of wood in a heated?

Answer 7

it will twist, cup or bow when drying out and cracks or gaps will appear.

Question 8

What are the advantages of seasoning?

Answer 8

1. greater immunity from decay and increased resistance to rot
2. increased strength and stability
3. helps preservatives to penetrate
4. makes wood less corrosive to metals

Question 9

When should tress be felled and why?

Answer 9

To reduce the time taken to season wood to the correct moisture content, trees should be felled in winter when they grow less, have less sap and therefore contain the least moisture.

Question 10

When does the least amount of shrinkage in a felled tree occur?

Answer 10

after it is cut down and whilst it is being seasoned.

Question 11

What are the 6 hardwoods?

Answer 11

oak
ash
mahogany
teak
birch
beech

Question 12

What are the 5 sotfwoods?

Answer 12

pine
spruce
douglas fir
larch
cedar

Question 13

What are the 6 manufactured boards?

Answer 13

plywood
marine plywood
aeroply
flexible plywood
chipboard
MDF

Question 14

Describe oak

Answer 14

Hard, tough, attractive grain, good weather resistance, contains tannic acid which will corrode steel screws or fixings

furniture, flooring

Question 15

Describe ash

Answer 15

Tough, attractive open grain which makes it more flexible, doesn’t splinter

sports equipment, tool handles

Question 16

Describe mahogany

Answer 16

Can contain interlocking grain (making it more difficult to work with), rick dark red colour

indoor furniture, shop fittings/cabinets, veneers

Question 17

Describe teak

Answer 17

Hard, tough, straight grain, natural oils resist moisture/acids/alkalis

outdoor furniture, lab benches

Question 18

Describe birch

Answer 18

Hard, straight closed grain, resists warping

furniture, indoor panelling

Question 19

Describe beech

Answer 19

Tough, closed grain, hard, does not impart a taste to food

Chopping boards, children’s toys, mallets

Question 20

Describe pine

Answer 20

Straight grain, knotty, can contain resinous knots

construction work, roof beams

Question 21

Describe spruce

Answer 21

Straight grain, resistant to splitting

indoor furniture

Question 22

Describe douglas fir

Answer 22

Straight or slightly wavy grain, few knots, stable, good resistance to corrosion

veneers, joinery/construction work

Question 23

Describe larch

Answer 23

Hard, tough, attractive grain pattern fades to silver upon exposure to outside, good resistance to moisture

garden furniture, cladding

Question 24

Describe cedar

Answer 24

Straight grain, can corrode ferrous metals due to acidic nature, low density, good sound damping, good resistance to moisture

sheds, greenhouses

Question 25

Describe plywood

Answer 25

Thin layers of wood are placed and glued 90 degrees to each other and compressed to form the board, good strength in all direction, no grain weaknesses, always has an odd number of layers

desk tops, indoor furniture

Question 26

Describe marine plywood

Answer 26

Similar construction to plywood but it is gap and void-free and uses specialist water and boil-proof glue to provide resistance to moisture, some marine plywoods are resistant to fungal attack

boat dashboards, boat lockers

Question 27

Describe aeroply

Answer 27

Plywood made from high-quality timber such as birch , available in very thin sheets, lightweight, easy to bend around a support frame

gliders, laminated furniture

Question 28

Describe flexible plywood

Answer 28

An odd number of layers glued together with the two outer layers made from open grained timber which allows the sheet to flex, bent and glued around a former to achieve a solid shape

laminated furniture, curved panels

Question 29

Describe chipboard

Answer 29

wood chips compressed within a resin such as urea formaldehyde

often veneered with a polymer laminate, kitchen worktops, desks

Question 30

Describe MDF

Answer 30

MDF is compressed wood fibres, although sometimes urea formaldehyde to added as an additional resin, it has 2 smooth faces, available in either standard grade or veneered with a layer of timber

model making, mould making, furniture such as bookcases

Question 31

Describe veneers

Answer 31

thin slices of wood less than 3m thick

decorative coverings for manufactured boards

Question 32

Describe MF laminates

Answer 32

Thin sheets of MF polymer, hard, tough, chemical resistant

decorative covering for chipboard for kitchen worktops

Question 33

What are the 6 timber stock forms?

Answer 33

1. Rough sawm
2. Planed square edge
3. Planed all round
4. natural wood
5. manufactured boards
6. mouldings

Question 34

What is rough sawn?

Answer 34

the wood comes directly from seasoning and has surfaces produced from initial conversion
it will have nominal sizes rather than accurate finished sizes

Question 35

What is planed square edge?

Answer 35

wood that only has one edge that is planed accurately and the rest are rough sawn

Question 36

When you plane wood, how much material does it remove?

Answer 36

3mm from the original nominal size

Question 37

What is planed all round?

Answer 37

wood has sides and edges that are all planed square, straight and level, leaving a smooth finish and ready to use
the PAR board is about 3mm smaller all round than the original rough sawn nominal size

Question 38

What are the advantages of manufactured boards for designers/manufacturers?

Answer 38

1. available in long, wide boards of uniform thickness and quality
2. very stable, not affected by temperature and humidity as much as sloid wood is
3. uniform strength across the board, no grain problems
4. difficult to split and available in flexible thin sheet form
5. generally less expensive than solid wood of a similar size
6. veneers can be applied to the surface for enhanced aesthetics

Question 39

What are some examples of mouldings?

Answer 39

skirting boards
wooden trims

Question 40

What are some defects of wood?

Answer 40

knots
splits

Question 41

What are the disadvantages of using natural wood as a manufacturing material?

Answer 41

1. the strength properties decrease when the wood it wet
2. natural wood is highly combustible
3. natural wood is susceptible to fungal attack, insect attack and rot
4. natural wood is anisotropic, which means it has different properties in different directions