The document provides instructions for various drafting and drawing techniques, including how to: 1. Fasten paper to a drafting board by taping down the corners and edges. 2. Use drafting tools like a compass to draw circles of a given radius centered on a point. 3. Draw different types of lines like horizontal, vertical, visible, and hidden lines. 4. Apply geometric techniques such as bisecting lines and angles, drawing parallel and perpendicular lines, and constructing triangles from given dimensions.

1. Erbil Polytechnic University

2. How to Keep Your Drawing Clean
Do Don’t

3. Preparation of
Tools

4. Fastening Paper to Drafting Board
1. Place the paper close to the table’s left edge.
2. Move the paper until its lower edge place about
the top edge of T-square.

5. 3. Align the top edge of the paper with T-square blade.
4. Attach the paper’s corners with tape.
Fastening Paper to Drafting Board

6. 5. Move T-square down to smooth the paper.
6. Attach the remaining paper’s corners with tape.
Fastening Paper to Drafting Board

7. Using the Tools

8. 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.

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

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

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

12. 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.

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

14. Types of line

15. 1-Visible line
2- Center line
3- Hidden line
4- Dimension line
5- Hatching line
6- Short cutting line
7- long cutting line
8- Border line
Types of lines

16. Drawing Sheet Arranging
Plan Plan Plan

17. Basic Dimensioning

18. Dimension Terminology:

19. 19
Arrowheads:
Should be 3 times longer than they are wide.

20. 1. Avoid placing dimensions on the part (inside of the
view).

21. 2. Place the first row of dimensions (10 mm)
away from the edge of the part.
Additional
stacks of
dimensions can
be a minimum
of (8mm) away
from each
other

22. 3. Extension lines may cross each other and over
other lines on the part, but dimension lines
should never be crossed. (Hint no “arrow-
headed” lines can cross “arrow-headed” lines)

23. 3. The overall dimension should always be given.
It should be placed outside of smaller dimensions
and be the farthest from the part.

24. 4. Do not duplicate dimensions and avoid using
unnecessary or superfluous dimensions

25. 5. For metric drawings, omit the use of the
millimeter (mm) notation following the numeral, as
millimeters are the default units.

26. 6. The origin for baseline or ordinate dimensions
used as a datum should be extended from a finished
edge  of the part.

27. 7. Extend leaders from the first or last word in a
note. Point them toward (but not touch) the center
of the circular features that they are specifying.

28. Angular features:
Dimension angular features with either:
X,Y coordinate location or Vertex location & degrees

29. Dimension Styles
Unidirectional dimensions
are read from the lower left
corner of the sheet
Aligned dimensions align
with individual dimension
lines.

30. Applied Geometry

31. To Bisect a Line
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.
(not to scale)
A
B
r1
Given
A
B
r1
3. Locate the midpoint.

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

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

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

35. To draw the line perpendicular to a
line at a point on the same line
r1
+
C
r2
r2 > r1
A
B
D

36. r2
+ C
r2
r1
To draw the line perpendicular to a
given line from a point not on the line
B
A
D

37. c- DRAWING A TRIANGLE WITH THREE NONE SIDES:
AB = 10cm, AB = 8cm,BC = 7cm
1. Draw the side of triangle AC with the none length (for example
AC=10cm).
2. With the length of AB=8cm open the compass and draw from
point A the arc S1.
3. With the length of CB=7cm open the compass and draw from
point C the arc S2 ,that will intersect with S1 in the position of
point B.
4. Link points A and C with point B to complete the triangle.
B
C
10cm
8cm
A
7cm
S1
S2

38. FILLET AND ROUND
Sharp corner
Fillet
Round
Round

39. 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?

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

41. To draw an arc of given radius tangent
to two perpendicular lines
Given arc radius r
center of the arc
Starting point
Ending point

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

43. +
C1
Given Two circles and the radius of the third circle = R
To draw a circle tangent to two circles I
+
C2

44. + +
C1
C2
R + R1
R + R2
R1
R2
C
center of the arc
To draw a circle tangent to two circles I
R

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

46. + +
C1
C2
To draw a circle tangent to two circles II
Given Two circles and the radius of the third circle = R

47. + +
C1
C2
R – R2
To draw a circle tangent to two circles II
Given Two circles and the radius of the third circle = R
R – R1
R1
R2
C
R

48. +
C1
+C2
To draw a circle tangent to two circles III
Given Two circles and the radius of the third circle = R
R + R2
R – R1
R1
R2
C

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

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

52. To draw a pentagon 5 sides
Given let AB be the length of one side

53. Draw a pentagon (5sids)
The location in circle