DT

• REASONS FOR SURFACE FINISHES

  Aesthetic and protection
• TIMBER FINISHES

  Painting, Lamination Varnish Wax and stain
• Polymer Finishes


  Polish,Vinyl and plastic dip coating
• Metal Finishes


  Power coating, Dip coating, shot blasting
• Galvinsing


  Coating metal or steel with zinc
• Elctroplating


  Coating with a thing layer by electrolysis
• What is lamination
• What is Lamination


  Lamination is the process of bonding two or more layers of timber for an improvement of strength
• What is tolerance


  Refers to the permissible variation from a specified measuremnt this commonly happens in engineering and manufactering processes
• what does 1000mm +/-1mm


  This means 999mm or 1001mm
• what does cad stand for

  Computer aided design
• what does cam stand for

  Computer aided manufacture
• CAD defintion


  CAD uses computers to create detailed plans and drawings
• Cam defintion

  This process is when computers help control machinery to make products precise and efficient
• CAD example

  2d design and On shape
• Cam example

  Laser cuter and 3d printing
• Automation

  Increase skill worker Decrease

  job opportunity
• + of CAD

  Ideas can be drawn and developed quickly

  View from diffrent angles
• -Cad

  Expensive set up

  Need skilled work force
• -CAM

  Expensive set up

  Need skilled work force
• + CAM

  Fast and accurate production

  Can run constantly on tasks
• Examples of CAM

  Laser cutter

  3D Printing
• Examples of CAD

  2d desighn

  Onshape
• MANUFACTURING PROCESSES Timber

  CNC Router

  CNC Lathe

  Lamination

  Bending
• MANUFACTURING PROCESSES POLYMER

  Blow moulding

  Injection Moulding

  Extrusion

  Rotational moulding

  Vacum forming
• MANUFACTURING PROCESSES Metal

  CNC lathe CNC Milling
• When considering the ecological and social implications of using polymers, it is likely that the polymer is non-renewable
• Some polymers are plant-based, but most are derived from crude oil, which cannot be grown and is a finite resource-there is only a certain amount within the Earth's crust
• A tremendous amount of energy is used to convert crude oil to a polymer, it is important to consider other materials or to reuse plastics already available
• The 6 Rs to reduce environmental impact


  • The designer
  • The manufacturer
  • The consumer
• Polymers


  • Most are obtained from crude oil
  • Some can be derived from natural sources, such as plants
• Polylactic acid (PLA)


  A common plant-based polymer used in 3D printers, obtained from corn starch
• Bioplastics are being continually developed to combat the environmental concerns related to the non-biodegradable properties of plastic polymers
• Process to produce polythene

  1. Crude oil is drilled and pumped to the surface

  2. Oil is transferred to an oil tanker and shipped to an oil distillery

  3. Oil is heated to break it down and obtain different products through fractional distillation

  4. Naphtha, a mix of hydrocarbons used for the production of many different plastic polymers, is vented off

  5. Monomers undergo polymerisation to make a polymer chain
• When crude oil is heated, many different chemicals are vented off from the heating column. The thick and dense material bitumen, used for road surfacing, is vented off from the hottest port of the column at the base
• Common stock forms of polymers


  • Sheet
  • Granules
  • Powder
  • Foams
  • Film
  • Filament
• Common stock forms


  Acrylic, Polypropylene, Polythene, Plastazote, PVC, PLA/ABS
• Vacuum forming


  High impact polystyrene (HIPS) is often the material used, as it heats up quickly depending on thickness
• Vacuum forming process


  1. The HIPS is heated

  2. The solid former is pressed into the HIPS from a bed that can rise

  3. The vacuum is turned on, removing all the air from around the former

  4. The HIPS takes the form of the solid former
• Former


  The solid shape that goes in the vacuum former