Unit 2

Unit 2

1. Raw materials

   • Are products extracted directly from nature
     • They may be of plant, animal or mineral origin. Air and water are raw materials too

2. Natural and processed materials

   • Industrial processes are applied to raw materials to turn then used to make other, more complex objects

3. Tools

   • Support tools
     • pincers
     • clamps
     • pliers
   • Assembly tools
     • torque
     • joining
   • Impact tools
     • hammer
     • mallet
   • Marking tools
     • pencils
     • scribe
     • punch
   • measurement tools
     • Goniometer
     • calliper
   • Cutting tools
     • cutter
     • punch
     • fret saw

4. The properteis of materials

   • mechanical
     • relate to a material is behaviour when subjeted to stress and loads
   • environmental
     • tell us about the impact materials have on the environment
   • thermal
     • indicate how the material behaves when subjected to heat

5. Types of wood

   • non-resinous
     • Comes from trees that have little resin and a fibrous texture
   • resinous
     • Comes from evergreen trees, which produce resin

6. Properties of wood

   • Hardness
   • Flexibility
   • Density
   • Hygroscopicity
   • toughness
   • splitability
   • sound conductibity

7. Forms of wood

   • strips
   • Panels
   • beams
   • boards and planks
   • sheets

8. wood working tools

   • cutting
   • impact
   • drilling