Topic 4 Timbers

Question 1

Characteristics of softwood

Answer 1

• 30 years to mature
• generally softer because of speed of growth
  reproduce by cones
• have needles
  do not lose needles in autumn

Question 2

scots pine

Answer 2

straight grained softwood but knotty. light fairly strong but easy to work with. cheap and readily available

Question 3

parana pine

Answer 3

hard and straight grained knot free strong durable expensive pale yellow

Question 4

spruce

Answer 4

creamy white with small hard knots not durable

Question 5

yellow cedar

Answer 5

pale yellow light but stiff and stable

Question 6

characteristics of hardwood

Answer 6

100 years to grow which is why they are harder
reproduced by flowers
broad leaves and are fruit bearing
lose their leaves every autumn

Question 7

Beech

Answer 7

straight grained hardwood with fine texture light in colour very hard so ideal to be used where it is being bashed around and used often. easy to work with

Question 8

oak

Answer 8

very strong wood light in colour. hard to work with. when treated looks elegant

Question 9

mahogany

Answer 9

easy to work with which is reddish brown. very expensive

Question 10

teak

Answer 10

durable oily wood which is golden brown and resistant to moisture

Question 11

seasoning

Answer 11

immune from decay and increases resistance to rot
increase timber strength and stability
helps preservatives to penetrate
makes timber less corrosive to metals

Question 12

natural seasoning

Answer 12

cheap but depends on weather conditions

Question 13

artificial seasoning

Answer 13

quicker more controlled method but more expensive

Question 14

Man made timber

Answer 14

made from wood products and have different properties to the wood they were made from

Question 15

MDF

Answer 15

glues wood fibres together using heat and pressure. they are smooth and strong. resistant to warping. layered structure which makes fixing to edges difficult.

Question 16

plywood

Answer 16

thin wood glued together at 90 degrees to each other. strong as it cannot split at the grain like solid timber

Question 17

characteristics of mmt

Answer 17

much cheaper for furniture 
classed as a composite as they use both wood and adhesive 
consistent quality
waste material can be used to make them
good dimensional stability

Question 18

types of attack on timber

Answer 18

dry rot - reduces timber to a sponge like consistency due to lack of circulation of air
wet rot - due to alternating wet and dry conditions
insects - consume timber which makes it weaker

Question 19

treatments

Answer 19

chemical based, removing damaged materials and spraying with a solution to prevent rot or infestation
varnishes, stains and paint can bemused to make timber more durable and enhance the look of the material
veneers placed on them to enhance and protect against the damp

Question 20

finishes

Answer 20

wax polish - wax oil produces a dull gloss shine and is made from beeswax. used on good quality furniture and has the ability to lift the colours of the grain.
stain - protect against fungus moisture and insect infestation. makes wood look more expensive
finishing oils - protects from moisture and provides low sheen finish
wood preserver - stops excess moisture which would cause the timber to split and rot
creosote - protects the integrity of the wood from attack from insects and fungal attack.