1. DIEDRIC SYSTEM

2. 2.4 Diedric system

3. 2.4 Diedric system
The diedric system represents the objects using a perpendicular projection on a plane

4. 2.4 Diedric system
The projection or VIEW consists of drawing just what we see when we are perpendicular to the object and to the plane
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5. 2.4 Diedric system
To define an object we only need 3 views, floor, front and profile:
Floor view: from the top of the object
Front view: facing the object
Profile view: from the side
Profile view
Floor view
Front view
Front view
Floor view
Profile view

6. Draw the left profile, floor and front view of your pencil case.

7. 2.4 Diedric system Diedric Rules
The front is usually indicated with an arrow
The views distribution
The front is always on top of the floor
The profile is situated the other way round, that is, the left profile is situated on the right
front
floor
Left profile
Right profile
floor
front

8. 2.4 Diedric system Remember:
The same height: the object has the same height on the floor and on the profile views
The same width: on the front and on the floor views
The same depth: on the floor and on the profile views

9. 2.4 Diedric system
Exercise: Draw the front, left profile and floor views of the class chair

10. 2.4 Diedric system
Exercise: Draw the front, profile and floor views of the class chair

11. 2.4 Diedric system
Where do we have to be situated to see these objects like circles?

12. 2.4 Diedric system

13. 2.4 Diedric system Exercise 11: Complete the views of the following objects
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14. 2.4 Diedric system Exercise 11: Complete the views of the following objects

15. 2.4 Diedric system Exercise 11: Complete the views of the following objects

16. 2.4 Diedric system Exercise 11: Complete the views of the following objects

17. 2.4 Diedric system
Non visible lines: when we know there is a hidden line we have to draw it using a discontinuous line
hidden line

18. 2.4 Diedric system
Insert video

19. 2.4 Diedric system
Activity: draw the front, floor and right profile views of this figure colouring each face in one colour.

20. 2.4 Diedric system
Activity: draw the front, floor y left profile views of this figure colouring each face in a different colour.

21. 2.4 Diedric system
Exercice: draw the right profile, front and floor views of these objects

22. 2.4 Diedric system

23. 2.4 Diedric system

24. 2.5 Marking and standardizing
The standardizing is the group of rules that defines technical drawing.
For example:
For paper size we use the DIN rule: A0,A1,A2…
The lines are:
Thick continuous lines: are used to outline objects
Thick discontinuous lines: indicate hidden lines
Thin continuous lines: are used for auxiliary measures and reference lines

25. 2.5 Marking and standardizing
Reference line
Measure
Measure line
Auxuliary Line

26. 2.5 Marking and standardizing
Outside thick continuous line
Thick discontinuous line for a hidden edge

27. 2.5 Marking and standardizing
Marking : indicating the real dimensions above the object

28. 2.5 Marking and standardizing
Activity: draw these views indicating which rules are broken
Wrong
Wrong
Wrong
Wrong
Correct
Correct
Correct
Correct

29. 2.5 Marking and standardizing.
Marking follows some rules: see page 37
The measure lines:
We place them parallel to the edge and slightly separated
They are limited by the auxiliary lines
The arrows are thin and enlongated, they go from one side to the other

30. 2.5 Marking and standardizing
Auxiliary lines
We place them perpendicular to the measure lines
They cross the measure line a little bit
They never cut the measure line

31. 2.5 Marking and standardizing
Activity: draw these views indicating which rules are broken
Wrong
Correct

32. 2.5 Marking and standardizing
The measures:
We indicate the real measure in milimetres, but “mm” is never written
They are placed above the measure line, never under it
We only use the extrictly necessary measures

33. 2.5 Marking and standardizing
Activity: draw these views indicating which rules are broken
Wrong
Correct

34. 2.5 Marking and standardizing
Activity: Draw the front, left profile and floor views of your pencil marking the measures

35. Let’s revise the important terms

36. Unit 2.Drawing applied to technology
What are we going to see in this unit?
2.1 Drawing tools and how to use them
2.2 Drafts and sketches
2.3 Drafting scale
2.4 Diedric system
2.5 Marking and standardizing

37. Vocabulary Paper size Cellulose Clay, graphite, lead
Hard and soft pencils
Erasers, technical pencil
Sixty and forty-five degree rules
Sketch, draft, free hand drawing, measures
Scale, real and drawn size, reduction, enlargement scales
To be reduced 100 times…
Length, height, width
Long, high, wide.