1. James Playford
Series Editor: Louise T Davies
Technical drawing

2. Lesson objectives/aims
Understand the production and use of detailed technical drawings.
Demonstrate a knowledge of:
- scale drawings
- plans and maps
- schematic maps
- self-assembly drawings
- sectional drawings
- exploded drawings.
© Folens 2009

3. Learning ladder By the end of the lesson: You must:
be able to interpret a range of technical drawings
be able to interpret plans and maps.
You should:
be able to produce a range of technical drawings
be able to produce plans and maps.
You could:
produce exploded drawings using ICT.
© Folens 2009

4. Introduction
As a Graphic Products student you will need to understand how to communicate complex, technical information in an organized and effective way.
As a design student you are in an unusual situation: you design and make your product.
In most industrial and commercial situations a designer will design and a production engineer will make.
Designers and engineers have their own language and you need to learn to speak it.
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5. Detailed technical drawing techniques
You need to be aware of three types of detailed technical drawings:
Sectional
Self-assembly
Exploded
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6. Learning task: self-assembly drawings
Self-assembly means that a product is not completely assembled at the factory.
The end user will need to complete the final assembly.
Name three items you have assembled yourself.
Did you get?
food
toys
furniture
computer systems
camping equipment?

7. Self-assembly products
Self-assembly techniques are employed by manufacturers to reduce shipping costs.
If an item can be packed in a smaller box you can fit more boxes in a crate, which will make it less expensive to ship.
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8. Task 1
Self-assembly drawings need to clearly communicate the sequence that the product will be assembled in, including details of which components and fixings are to be used for each stage.
Task: In small groups prepare a self-assembly instruction for this unit in the minimum number of drawings.
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9. Task 2
It is often necessary to communicate concepts in a non-linguistic way: without words.
Why is it in a manufacturer’s benefit to produce non-linguistic instruction sheets?
Task: In groups you will be assigned a word or phrase. You will need to design a diagram that takes the place of the word. The simpler the better.
Hammer
Rotate
Bolt
Place upside down
Glue
Mark the position
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10. Sectional drawings
Sectional drawings are often known as cut away drawings.
They allow hidden details of a product to be seen in great detail.
They are especially useful for complex products where internal parts are hidden from view.
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11. Learning task: sectional drawings
Which parts of this product would not be visible with a non-sectional drawing?
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12. Task 3
Your teacher will provide you with a cut open object for you to draw in section. Here is an example:
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13. Exploded drawings
Exploded drawings are another powerful method of communicating information about a product.
In an exploded drawing the individual components are moved apart to allow hidden details, including joining techniques, to be seen.
Which parts of this product would not be visible with a non-sectional drawing?
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14. Task 4
We are going to use our old friend the bookshelf again for this task.
The shelves are joined to the sides with two wooden dowels at each end.
Complete an exploded drawing of the bookshelf complete with dowels.
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15. Task 5 (1)
What is this a drawing of?
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16. Task 5 (2)
… and this?
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17. Learning task: scale drawings (1)
Why was the first obvious and the second much harder to see?
How can we draw large objects like oil rigs, buildings and aeroplanes when they are too large for the paper we have available?
The first one fitted on the screen, the second was too large and only a small part was visible.
© Folens 2009

18. Learning task: scale drawings (2)
The simple answer is just to draw small pictures of large objects, or large pictures of small objects.
As designers we need to work accurately and ensure the correct and true proportions.
Correct proportions give an accurate and professional appearance
Incorrect proportions look unprofessional and inaccurate
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19. Learning task: scale drawings (3)
We need to inform the people, viewing the drawing, of the scale we are using. This is expressed as a ratio, for example 2:1 or 1:30.
What is the correct ratio for these images?
2:1
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20. Plans (1)
In 3D
Plans allow us to represent complex 3D objects such as buildings in a very simple ‘bird’s eye’ fashion.
Plan
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21. Plans (2)
Plans are widely used in the construction of large products such as buildings or ships.
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22. Task 6
Draw a plan of this children’s play area.
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23. Maps Maps are used to represent physical areas in a plan view.
There are many styles of maps, including Ordnance Survey, road and stylized.
Which style is this map?
Answer: Stylized
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24. Schematic maps
The first popularized schematic map was produced for the London Underground by Harry Beck in 1934.
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25. Task 7
Choose one of the following situations and produce a schematic map:
The emergency exits need to be labelled on one of your school buildings. Use colours to demonstrate the evacuation from different zones.
Note your movement around school during the day. Use colours to represent movement between different lessons.
A new underground system or monorail in your home town has been built. Use colours for different lines.
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26. Plenary Why do manufacturers produce self-assembly products?
What advantages are there to non-language based instructions?
What is the function of sectional drawings?
Give an example of a component that will be made visible in a sectional drawing.
What are exploded drawings?
How do sectional and exploded drawings differ?
How does a scale drawing differ from a picture?
What are the key differences between a representational map and a schematic map?
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27. Extension
Investigate the production of exploded drawings using computer based virtual modelling software.
Produce a rendered exploded drawing in a virtual modelling software you are familiar with.
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28. Homework preparation
Rate your understanding of the topics listed below on a scale of 1to5 (1 being low).
self-assembly
sectional
exploded
plans
schematic map.
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29. Homework
Based on your self-evaluation choose the drawing style you feel least comfortable with and complete the associated task for homework.
Self-assembly: Complete a self-assembly instruction for a clock.
Sectional: Complete a sectional drawing of a torch.
Exploded: Complete an exploded drawing of a flask.
Plans: Complete a plan of your school grounds.
Schematic map: Complete a schematic map of a local one-way road system.
© Folens 2009