Zusammenfassung der Ressource
Technology Unit 1
- Symbols
- Start/Stop
- Outputs
- Decision/Compare
- Wait/Increment/Decrement/Expression
- Manufacture
- WOOD
- Softwoods:
Come from
coniferous
trees, which
can take
30-50 years
to reach
maturity
and are also
cheaper
than
hardwoods.
- Pine, Fir + Cedar
- Hardwoods:
Come from
deciduous
trees, they
can take up
to 100 years
to reach
maturity and
grow in
warmer
climates.
- Oak, Mahogany + Birch
- Man-Made Boards:
These are made by
cutting up solid wood
and putting back in a
variety of ways, this
provides stronger, more
stable and cheaper
wood.
- Plywood,
Chipboard +
Medium Density
Fibreboard
- Joining Wood.
- Butt Joint:
Simplest of all
joints, it is rather
weak but can be
strengthened by
glue.
- Rebate Joint:
This corner
joint is
stronger and
more rigid.
- Dowel Joint:
This is a butt
joint which is
strengthened by
dowels.
- Halved Joint: One
piece of wood
crosses the other
and are glued
together.
- Mitre Joint:
Two pieces of
wood joined
at a 45° angle.
- Finishing Wood.
- Staining - this changes the woods colour
but still allows for the grain to be visible.
- Varnishing - this covers the surface of the
wood with a protective coating.
- Painting - this changes the colour and
hides the grain pattern
- PLASTICS
- Thermoplastics:
These soften
when heated and
keep their shape
when cooled.
- Polystyrene -
cheap and light
weight
- PVC -
strong
and
flexible
- Acrylic -
hard
and rigid
- Thermosetting:
These are stiffer and
stronger and will not
soften.
- Urea Formaldehyde -
hard and a good
insulator
- Melamine Formaldehyde -
hard and heat resistant
- METALS
- Ferrous Metals contain iron.
- Cast Iron, Stainless Steel
- Non-Ferrous do not contain iron.
- Copper, Brass