1. Chapter 2
Using Drawing Tools
& Applied Geometry

2. TOPICS
Using of Tools
Basic Line Types
Applied Geometry

3. Using the Tools

4. Function of the Tools Tools Shape to be drawn 1. T-square
Straight line
2. Triangles
3. Compass
Arc, Circle
4. Circle template

5. Using the Compass
1. Locate the center of the circle by two intersecting lines.
2. Adjust the distance between needle and lead to a distance
equal to radius of the circle.
3. Set the needle point at center.

6. Using the Compass
4. Start circle. Apply enough pressure to the needle, holding compass handle between thumb and index fingers.
5. Complete circle. Revolve handle clockwise.

7. Draw a Horizontal Line
1. Press the T-square head against the left edge of the table.
2. Smooth the blade to the right.

8. Draw a Horizontal Line
3. Lean the pencil at an angle about 60o with the paper in the direction of the line and slightly “toed in”.
4. Draw the line from left to right while rotating the pencil slowly.

9. Draw a Vertical Line 1. Set T-square as before.
Place any triangle on T-square edge.
2. Slide your left hand to hold both T-square and triangle in
position.

10. Draw a Vertical Line 3. Lean the pencil to the triangle.
4. Draw the line upward while rotating the pencil slowly.

11. Draw a line at 45o with horizontal
1. Place 45o triangle on the T-square edge and press them firmly against the paper.
2. Draw the line in the direction as shown below.

12. Draw a line at angle 30o and 60o
1. Place 30o-60o triangle on the T-square edge and press
them firmly against the paper.
2. Draw the line in the direction as shown below.

13. Draw the lines at 15o increment
0 deg.
15 deg.
=  deg
30 deg.
Already
demonstrated.
45 deg.
60 deg.
75 deg.
= deg
90 deg.
Already
demonstrated.

14. Draw the line passing through
two given points
1. Place the pencil tip at one of the points.
2. Place the triangle against the pencil tip.
3. Swing the triangle around the pencil tip until its edge align with the second point.
4. Draw a line. A B A B
Given

15. Basic Line Types

16. NOTE : We will learn other types of line in later chapters.
Basic Line Types
Name according
to application
Types of Lines
Appearance
Continuous thick line
Visible line
Continuous thin line
Dimension line
Extension line
Leader line
Dash thick line
Hidden line
Chain thin line
Center line
NOTE : We will learn other types of line in later chapters.

17. Visible lines represent features that can be seen in the
Meaning of Lines
Visible lines represent features that can be seen in the
current view
Hidden lines represent features that can not be seen in the current view
Center line represents symmetry, path of motion, centers of circles, axis of axisymmetrical parts
Dimension and Extension lines indicate the sizes and location of features on a drawing`

18. Example : Line conventions in engineering drawing

19. Applied Geometry

20. To Bisect a Line Practice :take AB=100 Given
1. Swing two arcs of any radius greater than half-length of the line with the centers at the ends of the line.
2. Join the intersection points of the arcs with a line.
3. Locate the midpoint. r1
Given A B r1 A B
Practice :take AB=100

21. To Bisect an Angle Practice : take an angle =30 Given
1. Swing an arc of any radius whose centers at the vertex.
2. Swing the arcs of any radius from the intersection points between the previous arc and the lines.
3. Draw the line. A B C
(not to scale)
Given A B C r1 r2 r2
Practice : take an angle =30

22. To draw the line parallel to a given line with a specified distance
Given distance = r r
Practice: the line= 120
the distance r=20

23. To draw the line parallel to a given line with a specified distance
Given distance = r r r
Repeat

24. To divided an straight line to equal parts: Known: line ABC A B
Practice : AB= 100
5 parts

25. To transfer an angle: Known: angle ABC M R M1 N N1 R1
Practice: the angle ABC=45

26. To draw a triangle Known: triangle’s member AB , BC, CA R2=BC R1=CA
Practice: AB=110
BC=90
AC=70

27. To draw a regular pentagon
Known: length of AB D
R=AB
R1=OF
R2=BG F A B G O
Practice: AB=40

28. To draw a regular pentagon inside a circle
Known: circle of radius R A B C E
Practice: R=20

29. To draw a hexagonal shape inside a circle
Known: circle of radius R C D R R A B E F
Practice: R=60

30. To divided a circle into 8 equal parts:
Known: the radius of the circle C 1 7 5
The same way we find points 7 & 8 r
r not to scale 4 2 O 6 8 3
Practice: R=50

31. FILLET AND ROUND
Round
Sharp corner
Fillet
Round

32. FILLET AND ROUND
To draw the arc, we must find the location of the center of that arc.
How do we find the center of the arc?

33. To draw an arc of given radius tangent to two perpendicular lines
arc radius r r r

34. To draw an arc of given radius tangent to two perpendicular lines
arc radius r
center of the arc
Starting point
Ending point
Practice: the angle=90
R=30

35. To draw an arc of given radius tangent to two lines
arc radius r r r + +

36. To draw an arc of given radius tangent to two lines
T.P.1
T.P.2
Practice: angle=120 , 50
R=30

37. To draw a line tangent to a circle at a point on the circle
Given C

38. When circle tangent to other circle
Tangent point R1 C1 R2 C2
R1 + R2
The center of two circles and tangent point lie on the same straight line !!!

39. To draw a circle tangent to two circles I+
Given + C2 + C1
Example

40. To draw a circle tangent to two circles I
Given
Two circles and the radius of the third circle = R + + C2 C1

41. To draw a circle tangent to two circles I
Given
Two circles and the radius of the third circle = R
R + R2
center of the arc
R + R1 R2 C R R1 + + C2 C1
Repeat

42. When circle tangent to other circle
Tangent point R1 R2 C1 C2
R2  R1
The center of two circles and tangent point must lie on the same straight line !!!

43. To draw a circle tangent to two circles II+
Given + C2 + C1
Example

44. To draw a circle tangent to two circles II
Given
Two circles and the radius of the third circle = R + + C2 C1

45. To draw a circle tangent to two circles II
Given
Two circles and the radius of the third circle = R R R2 R1 + +
R – R2 C2 C1
R – R1 C
Repeat

46. To draw a circle tangent to two circles III
Given
Two circles and the radius of the third circle = R R2 R1 + C2 + C1
R + R2
R – R1 C

47. Practice
The distance O1 O2= 60
R1=30
R2=20
R=30 ,70,50

48. To draw an approximate ellipse
Given
Major and minor axes

49. To draw an approximate ellipse
Given
Major and minor axes
Repeat

50. Practice
1. Major axes AB=100
Minor axes CD=50
2. Page 27: practice no. (2.24)

51. How to Keep Your Drawing CleanDo
Don’t