TIMBERS - Sources of Timber Flashcards
What are the two types of timber?
natural timber (hardwood & softwood) and manufactured timber
what are hardwoods?
Woods that come from deciduous trees with broad leaves (they loose their leaves in the winter).
what are the qualities of hardwood trees?
They take a long time to grow, so they are rarely planted and are expensive
Their growth rings are much smaller that softwood (they grow slowly), making the grain closer
They grow in tropical regions and temperate climates. Eg Amazonian Forest and Europe
what are softwoods?
Woods that come from coniferous trees with needle-like leaves (the leaves normally stay on during the winter).
what are the qualities of softwood trees?
They grow quickly, so are often commercially grown and are cheaper than hardwoods.
Their growth rings are much wider than hardwoods, so the grain is wider. (since they grow quickly)
They grow in colder regions such as the Alpine climates.
what are manufactured timbers?
timbers made from leftover wood such as sawdust and wood chippings
what are the advantages of manufactured timbers over natural timbers?
they can be made into large sheets rather than being restricted to the size of a tree trunk
they are cheaper than natural timbers as they are made from waste wood
no weak point as there is no grain
what type of wood is beech?
hardwood
what type of wood is mahogany?
hardwood
what type of wood is oak?
hardwood
what type of wood is balsa?
hardwood
what type of wood is jelutong?
hardwood
what type of wood is birch?
hardwood
what type of wood is ash?
hardwood
what type of wood is pine?
softwood
what type of wood is cedar?
softwood
what type of wood is larch?
softwood
what type of wood is MDF?
Manufactured
what does MDF stand for?
Medium-density fibreboard
what type of wood is plywood?
manufactured
what type of wood is chipboard?
manufcatured
Working properties of beech
tough
hard
close/dense grain
finishes well
durable
working properties of mahogany
hard
close/dense grain
finishes well
working properties of oak
tough
hard
(close/dense grain)
finishes well
durable
working properties of balsa
lightweight
easy to form
soft
working properties of jelutong
(close/dense grain)
soft
working properties of birch
hard
close/dense grain
durable
working properties of ash
tough
hard
(close/dense grain)
(lightweight)
good elasticity/flexibility
finishes well
durable
working properties of pine
lightweight
but durable
working properties of cedar
lightweight
(more expensive than pine but not as durable)
working properties of larch
tough
lightweight
durable
working properties of MDF
easy to finish
absorbs moisture (not suitable for outdoor use)
working properties of plywood
good elasticity/flexibility
easy to finish
working properties of chipboard
good elasticity/flexibility
tough …
will withstand knocks and bumps
does not break/dent/bruise
hard …
withstand rubbing/wearing/abrasion
will not wear away/rub/damage/will last a long time
close/dense grain …
will not splinter easily
does not cause harm/injury to the user
lightweight …
will not add too much weight on the structure
will not put unnecessary weight on the foundation
good elasticity/flexibility …
will bend and flex a little bit
therefore absorbing some of the impact/shock
finishes well …
results in a nice smooth surface that can be varnished/waxed
improves lifespan
durable …
withstand wear, pressure or damage
will not damage/will last a long time
which woods come from the alpine forests
pine, cedar, larch
which woods come from european forests
oak, beech, ash, birch
which wood comes from amazonian forests
mahogany
how is MDF made?
tiny particles of timber are compressed together with a resin adhesive
how is plywood made?
layers of veneer are glued at 90° angles, for strength
how is chipboard made?
many tiny chips of timber are mixed with glue and compressed into sheets
what is a knot?
a knot in timber marks where a branch one grew out on the tree
knots often …
fall out of planks
so it is preferable to use timber without knots, unless for decorative purpose
what are the ways that colour can be used in a product?
to make different parts stand out
for aesthetic purposes
to make the product seem of a higher quality
how can the colour of a plank be altered?
through wax, varnishes, stains and paints
both hardwoods and softwoods produce a new layer under their bark each year called a …
growth ring
for hardwoods the growth rings are …
closer together
or softwoods the growth rings are …
further apart
hardwoods have two long vessels known as …
fibres and pores
fibres are …
cells within the wood that can be extracted to make other products such as paper
pores are …
vessels that allow water to travel within the tree. they appear as tiny holes
often pores need to be …
filled with wood filler to create a smooth finish
heartwood is the …
centre of the tree
sapwood is the …
outside layer of the tree
hardness is …
the ability to withstand cutting and scratching
to resist mechanical indentation or abrasion
toughness is …
the ability of a material to absorb energy and deform without fracturing
to withstand being hit
durability is ..
the ability of a material to withstand wear, pressure or damage
to last a long time
elasticity is …
the ability of a material to return to its original shape after being stretched or compressed
tensile strength is …
the ability of a material to resist breaking under tension (being pulled)
compressive strength is …
the ability of a material to resist breaking under compression (under a crushing force)
what is trend forecasting?
trend forecasting is when manufactures and retailers try to predict the trends over the following years so that they can design and make products that people will want in the future. -social footprint
what is the impact of logging on communities?
provides employment
but many lose their homes and their traditional way of life, wildlife is also destroyed which many communities rely on for food - social footprint
timber can be disposed through …
burning to create heat, which is useful if well-managed
letting it biodegrade and rot away over time
timber can be recycled through …
using the waste wood from it and turing it into chipboard or MDF
reusing the timber for something else e.g sawing it into smaller pieces and using it elsewhere
timber can not be disposed like metal and plastics which …
are melted and re-moulded
the ecological footprint of a product is the …
amount of global resources used to make it
need to do
ecological footbprint
