working drawings - part 1

• What does orthographic projection combine?

  Plan, end, and front views
• Why are orthographic drawings called working drawings?

  They provide all information needed for manufacturing
• What is the standard for engineering drawing in the UK?

  BS 8888
• What does the symbol in third angle orthographic projection indicate?

  Arrangement of views in the drawing
• Where does the plan appear in third angle orthographic projection?

  Above the front elevation
• How is the end elevation drawn in third angle orthographic projection?

  Relative to the direction of view
• What are the common scales used in orthographic drawings?

  • Scale 1:2 (half actual size)
  • Scale 1:1 (actual size)
  • Scale 2:1 (twice actual size)
• What is the purpose of scale in working drawings?

  To represent actual size of the product
• What does tolerance refer to in engineering drawings?

  Maximum acceptable deviation from nominal size
• What measurement units are commonly used in the UK for engineering drawings?

  Millimetres
• What is the minimum diameter of an 80 mm bar with a tolerance of +0.00, -0.05?

  $79.95 \text{ mm}$
• What is the layout of a third angle orthographic drawing?

  • Plan view at the top
  • Front elevation in the middle
  • End elevation on the side