Blueprint Line Types
Read each line type in the column titled “type of line”
Examine each line type under the column titled “appearance”
Read the description for each type of line in the “description” column.
Then slowly examine the line type example and take note of what it will
look like when it is being used in its application.
Types of Lines
TYPE OF LINE
APPEARANCE
DESCRIPTION
Object Line
Heavy, solid,
unbroken line.
Used to indicate
visible edges of
an object.
Hidden Line
Thin mediumfine thickness
line with short
evenly spaced
dashes (not
dots).
Used to indicate
concealed (not
visible) edges.
EXAMPLE
Centre Line
Thin mediumfine line made
up of series of
alternating short
and long
dashes. Used to
indicate centre
of circles, arcs,
and axes of
symmetry.
Dimension Line
Thin mediumfine lines with
arrowheads at
each end and a
dimension
placed in the
middle to
indicate a size.
Extension Line
Thin fine lines
extending from
but not touching
the object. Used
to indicate
where the
dimension
points starts and
ends.
Leader Line
Thin fine line
with an
arrowhead on
one end. Used
for the purpose
of adding a note
or a dimension.