Unit 2.Drawing applied to technology

1. Unit 2.Drawing applied to technology

2. 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

3. 2.1 Drawing materials and instruments Paper • Paper is made of cellulose that is obtained from trees • The paper size that we use is A4 . It is the result of dividing 1 m2 (A0) four times by half the longest side.

4. 2.1 Drawing materials and instruments Pencil • A pencil has a lead covered with wood. The lead is made with graphite and clay Lead clay Wood cover Graphite

5. 2.1 Drawing materials and instruments Pencil hardness The more clay it contains the harder the lead will be. We use letter H for hard pencils and letter B for soft ones. Hard: H Soft: B less clay More clay Technique draw Artistic draw

6. 2.1 Drawing materials and instruments Mechanical pencils They hold a graphite lead. They can be used for technical drawing (if used )with a soft lead. ERASERS Erasers are made of rubber, they absorb graphite and erase it.

7. 2.1 DRAWING TOOLS THE RULER It is a precision tool that makes it possible to measure and to transfer a distance. TRIANGULAR SET SQUARE A set square is a tool for drawing perpendicular (vertical) and parallel lines and for obtaining angles. There are 2 types of trianglular set squares A 45 degree A 60 degree

8. 2.1 Drawing materials and instruments How to draw vertical and parallel lines with the set square Vertical: Parallel: Activity: Draw the set squares in your notebook as you can see them in both positions

9. 16 cm 16 cm 2.1 Drawing materials and instruments Activity :Draw a chessboard using the set square. The separation between squares is 2 cm! square

10. 2.1 Drawing materials and instruments Drawing angles: we can get 15º, 30º, 45º, 60º, 75º, 90º, 120º, 135º…angles combining the 30º, 45º , 60º and the 90º angles from the set squares You don't have to copy them because you can find them in your text book on page 25

11. 2.1 Drawing materials and instruments Drawing angles exercise: you have to obtain, 45º, 75º, 90º, 120º angles combining the set squares

12. 2.1 Drawing materials and instruments Drawing angles exercise: you have to obtain, 45º, 75º, 90º, 120º angles combining the set squares

13. 2.1 Drawing materials and instruments The Compass It is used for drawing circles and angles Advice: sharpen the lead tip by rubbing it on a fingernail file

14. 2.2 DRAFT AND SKETCH • DRAFT: Itis a free hand drawing (just with a pencil). We show an idea or object without totally defining it. Page 41

15. 2.2 DRAFT AND SKETCH • ATTENTION! • A DRAFT IS NOT A BAD DRAWING AND A SKETCH IS NOT A GOOD DRAWING !!!!!!

16. 2.2 DRAFT AND SKETCH The sketch: Itis a free hand drawing too, but it includes the measures, therefore it shows the precise size and a shape similar to the final drawing. measure Page 41

17. 2.2 DRAFT AND SKETCH • Activity: draw a sketch of your home cupboard.

18. 2.2 DRAFT AND SKETCH the Sketch

19. 2.3 Drafting scale • We define scale as the relation between the drawing size and the real object A model uses a reduction scale

20. 2.3 Drafting scale 1:2 The Drawing size The Real size Page 38

21. 1:1200 1cm drawing 1200 reality Page 38 2.3 Drafting scale 1 cm measured on the drawing is equivalent to 1200cm in reality

22. Scale types: Reduction scale: it is used to represent big objects, so they can be drawn on paper We usually use: 1:2 1:5 1:10… In this example we have reduced 1000 times the real size of the tree 2.3 Drafting scale 1:1000 Real Real Real drawn

23. Enlargement scale: it is used to represent small objects so we can see them on paper It is used: 2:1 5:1 10:1 … In this example the drawing is two times the real object 2:1 2:1 2.3 Drafting scale Safety pin Real Drawing

24. An example of scale application Let’s draw a pencil that is 10cm high and 1cm wide using different scales: 2:1, 1:2, 1:4 1cm 10cm 2.3 Drafting scale

25. 2.3 Drafting scale 2:1 Scale 2:1 Real

26. 2.3 Drafting scale 2:1 Scale 1:2 Real 1:2

27. 2.3 Drafting scale 2:1 2:1 2:1 Scale 1:4 Real Real Real Real 1:2 1:2 1:2 1:2 1:4

28. Scale exercise This drawing is 4,5cm long and 2,5 cm high, if we have used a 1:100 scale How high and long is the real car? 2.5cm 4.5cm 2.3 Drafting scale

29. 2.5cm 4.5cm 2.3 Drafting scale Scale 1:100

30. Activity: Let’s draw a plan of your classroom using your feet and your hands applying the suitable scale to draw it 1 foot: 20cm 1 hand: 10cm 2.3 Drafting scale

31. 2.3 Drafting scale 24 feet are equivalent to 480cm Therefore we have 4,5 hands = 45cm 4hands x 18cm/hand= 72cm 3hands x 18cm/hand= 54cm 31 feet x 20cm/foot= 620cm 24 feet x 20cm/foot=480cm 3,5 hands=35cm 31 feet are equivalent to 620cm

32. 2.3 Drafting scale Which scale could we use to draw the classroom and your desks on your notebooks?

33. 2.3 Drafting scale Let’s use the 1:100 scale, so the drawing will be 100 times smaller than reality

34. Homework: Draw a plan of your bedroom using your feet and your hands. Apply a 1:25 scale to draw it 1 foot: 20cm 1 hand: 10cm 2.3 Drafting scale

35. 15feet= 300cm 20 pies = 400cm