TECHNOLOGY

TECHNOLOGY

1. WOODS

   • HARDWOOD
     • grows south
     • balsa oak
     • apple and fruit can be grown
   • SOFTWOOD
     • splity
     • evergreen
     • grows north
     • softwood
   • MANUFACTURED BOARDS
     • CHIPBOARD
       • MADE FROM WASTE MATERIALS.
       • VERY STRONG
       • IT WILL SOAK UP WATER
       • SURFACE OFTEN COVERED IN PLASTIC
       • NO GRAIN
     • HARDBOARD
       • VERY CHEAP
       • USED FOR BACK OF CABINET
       • SOAKED IN RESIN
       • MADE FROM COMPRESSED FIBRES
       • SIDES ARE VERY SMOOTH
       • NOT VERY STRONG AS GRAIN
   • WOOD JOINS
     • halving joints: are made by cutting away half the thickness of the material on each half of the joint.
     • butt joints: formed like a castle wall and you connect them together and they become solid.
     • rebate joints: are also know as lap joints. one part of the two pieces being joined is left plain and the other has a rebate cut into it.
     • housing joints: can be cut in natural timber and manufactured boards. they are commonly used for cabinets .
     • tension joints: mortise is a hole which another piece of wood is to connected to make it a snug fit.
     • dowel joints: dowel joints are the same as butt joints, but reinforced.
   • WOOD FINISHES
     • for a good wood finish you can plane the wood.
     • glass-papering (sanding) a coarse paper should be used first then fine paper.
     • varnish: matt non shiny, satin slightly shiny,gloss ver shiny.
   • LAMINATING WOOD
     • advantages: strong, designed for heavy traffic, easy to maintain and clean, less expensive.
     • disadvantages: not environmental friendly, only last 10-15 years, can't be sanded and they do not reduce sound.

2. METALS

   • FERROUS
     • STEEL
     • MILD STEEL
     • STAINLESS STEEL
     • CARBON STEEL
     • CONTAINS IRON
   • NON-FERROUS
     • METALS THAT DONT STICK TO MAGNETS.
     • DIFFERENT FORMATS ANGLE, CHANNEL, FLAT, BAR AND TUBE
     • ALUMINIUM
     • TITANIUM
     • BRONZE
     • GOLD
   • HEAT TREATMENT
     • hardening: a piece of hardened steel is polished
     • tempering: the metal is heated up to a set temp
     • case-hardening: mild steel is heated up to a cherry red and then dipped into carbon powder.
     • annealing: heated up then allowed to cool
     • normalizing: heated cherry red then dipped into water.
   • SAND CASTING OF METAL
     • the drag and the cope.
   • CENTRE LATHE
   • TAPPING AND THREADING
     • threading is the cutting of an external screw thread using a split die.
     • tap wrench, taper, plug, square, clockwise, split die and anticlockwise.
   • NUTS, BOLTS AND SCREWS
     • difference between a bolt and a machine nut is a bolt has a flat hexagonal shape machine screw has a divot.
     • wing nut can be tightened by man
     • washers: plain and spring
     • nuts: nylon looking nut, wing nut and standard hex nut.
     • bolts: coach and hex head.
     • screws: countersunk, round head and raised head.

3. ADHESIVES

   • contact adhesives, ova, tensol cement, cascamite and export resin.

4. PLASTIC PROCESS.

   • blow moulding, compression moulding, vacuum moulding and injection moulding.

Images and files in the map