TYPES OF LINES, LETTERING
& NUMBERING
Objectives
After studying this unit, the student will be able to:
Identify the various types oflines.
State the application ofeach line.
Draw types of lines correctly.
Differentiate between perpendicular and parallel lines.
Construct perpendicular and parallel lines.
Distinguish between lower and upper case letters.
Write lower and upper case letters.
Write numbers 0 to 9
correctly.
As explained earhier, technical drawing is an international
combination of different types of lines language in which a
different types of lines, their names and expresses specific ideas. Below shows
how they may be applied.
1.3.1. IDENTIFICATION OF
LINES
Definition: A line is defined as the
Various types of lines are used in shortest
possible distance between two points.
techinical drawing to depict a
variety ofideas.
Units 1.3.2 and 1.3.3
however, show the various types oflines and their
1.3.2 LINES AND THEIR
applications.
Table 1.1 Shows the
APPLICATIONS OR USES
types of lines and their
applications.
TYPES OF LINES
Continuous thick APPLICATIONS
Visible outlines and
edges
Fictitious outlines and
Continuous Thin edges
Dimension and leader lines
Hatching
Outlines of adjacent
Wavy Outlines of revolved parts
Limits of partial viewssections
or sections
when the line is not an axis
16
, Short dashes (thin) Hidden outline and edges
Chain (thin) Centre lines
Extreme positions of moveable parts
Chain (Thick at ends) Cutting planes
Chain (thick) Indication of surfaces which have to
meet special requirement
Indicate long breaks
Table 1.1 Lines and their applications
1.3.3 DRAWING TYPES OF LINES
a) Perpendicular line
perpendicular line is a straight line which intersects another straight line at an angle
A
of90.
A perpendicular line can be draw using a rule and set squares, a Tee square and set
squares, a protractor and a Tee square or by construction.
A perpendicular sign is denoted as_hor shortened as lar
b)
a)
Fig. 1.31 Perpendicular Lines
& NUMBERING
Objectives
After studying this unit, the student will be able to:
Identify the various types oflines.
State the application ofeach line.
Draw types of lines correctly.
Differentiate between perpendicular and parallel lines.
Construct perpendicular and parallel lines.
Distinguish between lower and upper case letters.
Write lower and upper case letters.
Write numbers 0 to 9
correctly.
As explained earhier, technical drawing is an international
combination of different types of lines language in which a
different types of lines, their names and expresses specific ideas. Below shows
how they may be applied.
1.3.1. IDENTIFICATION OF
LINES
Definition: A line is defined as the
Various types of lines are used in shortest
possible distance between two points.
techinical drawing to depict a
variety ofideas.
Units 1.3.2 and 1.3.3
however, show the various types oflines and their
1.3.2 LINES AND THEIR
applications.
Table 1.1 Shows the
APPLICATIONS OR USES
types of lines and their
applications.
TYPES OF LINES
Continuous thick APPLICATIONS
Visible outlines and
edges
Fictitious outlines and
Continuous Thin edges
Dimension and leader lines
Hatching
Outlines of adjacent
Wavy Outlines of revolved parts
Limits of partial viewssections
or sections
when the line is not an axis
16
, Short dashes (thin) Hidden outline and edges
Chain (thin) Centre lines
Extreme positions of moveable parts
Chain (Thick at ends) Cutting planes
Chain (thick) Indication of surfaces which have to
meet special requirement
Indicate long breaks
Table 1.1 Lines and their applications
1.3.3 DRAWING TYPES OF LINES
a) Perpendicular line
perpendicular line is a straight line which intersects another straight line at an angle
A
of90.
A perpendicular line can be draw using a rule and set squares, a Tee square and set
squares, a protractor and a Tee square or by construction.
A perpendicular sign is denoted as_hor shortened as lar
b)
a)
Fig. 1.31 Perpendicular Lines
