Transcript Graphic Communication - Thurso High Technologies

National 4/5
Graphic
Communication
Signs & Symbols
Dimensioning
Scale Drawings
Dimensioning
We dimension objects to show what
size they are.
 This is vital when we pass our
drawings onto a craftsperson to make
the object.

Dimensioning
Dimensions are drawn to British
Standards.
 This means that all dimensions are
always drawn the same way.
 Dimensions you show will always be
measured in millimetres so you do not
have to show units.

Dimensioning
50
Horizontal dimensions
are read from the
bottom of the page.
Dimensioning
40
Vertical dimensions are
read from the righthand side of the page.
40
Dimensioning
40
Vertical dimensions are
read from the righthand side of the
page.dimension figures
should never touch the
outline of the object.
Dimensioning
40
Leader lines are
used to bring the
dimension away
from the drawing.
There should always
be a gap left between
the object and the
leader line.
Dimensioning
50
The arrowheads used on
the dimension line should
be kept small and slim and
the point of the
arrowheads should touch
the leader lines.
Dimensioning
Larger dimensions
should be drawn further
away from the object.
100
25
25
25
25
Smaller
dimensions like
these should be
placed in line.
Dimensioning
10
30
When dimensions are taken
from one leader line then this
would be called a datum line
Dimensioning
The symbol Ø stands
for diameter.
Ø45
Circles should always be
dimensioned to show
their diameter.
Dimensioning
The symbol r
stands for radius.
r20
Curves should always be
dimensioned to show
their radius.
Dimensioning - Rules







Show a dimension only once.
Dimensions should only ever be read from
bottom or the right-hand side of the page.
All sizes are shown in millimetres.
Your dimensioning figures should never touch or
interfere with any part of the drawing.
Ø is the symbol used to show a diameter, while r
is used to show a radius.
Show the diameter of circles.
Show the radius of curves.
Signs
Signs are used to convey information
in pictorial form.
 This has many advantages over
written instructions.
 People who talk different languages
can understand the same common
signs.
 Instructions for some tasks can be
clearer when given as drawings.

Signs & Symbols
Signs & symbols are commonly used
in everyday situations.
 Roadsigns, information, engineering
symbols, flow charts and circuit
diagrams are types of drawings that
are used to communicate graphically
everyday.

Warning signs


Warning signs are triangular in shape. They
have a black border, a yellow background and a
black symbol.
They warn people of hazards that could cause
personal injury or pose a threat to peoples’
health.
General warning sign
Prohibition


Signs & symbols are commonly used in
everyday situations.
Roadsigns, information, engineering symbols,
flow charts and circuit diagrams are types of
drawings that are used to communicate
graphically everyday.
Mandatory


Signs & symbols are commonly used in everyday
situations.
Roadsigns, information, engineering symbols, flow charts
and circuit diagrams are types of drawings that are used
to communicate graphically everyday.
Safe condition


Signs & symbols are commonly used in everyday
situations.
Roadsigns, information, engineering symbols, flow charts
and circuit diagrams are types of drawings that are used
to communicate graphically everyday.
Fire safety


Signs & symbols are commonly used in
everyday situations.
Roadsigns, information, engineering symbols,
flow charts and circuit diagrams are types of
drawings that are used to communicate
graphically everyday.
Signs - Kitemark
The Kitemark is used to tell
consumers that the products they buy
are safety tested to BSI standards.
 All products sold must carry this
Kitemark to be legally sold.

The British
Standards
Kitemark.
Signs - Fragile

This mark is placed on breakable
objects’ packaging to tell people
handling the box to treat it with care.
The Fragile
symbol.
Signs - Recycled
This mark is placed on recycled objects to
tell the consumer that they are buying a
recycled product.
 This is a big advertising point as
companies like their products to be seen
as being environmentally friendly.

Signs - Disabled

This is used to show disabled access.
Signs - male & female

These signs are used commonly to
distinguish the male and female toilets.
Flow Charts
A Flow Chart is a method of showing
the correct steps to follow in order to
complete some type of problem.
 There are some symbols used in flow
charts to show certain processes that
have to be done when completing the
problem.

Flow Charts

These symbols are shown below.
Process
Start/Stop
Decision
Input/Output
Start
Flow Charts
Has button
been pushed?

An example of a
flow chart for a
pelican crossing is
shown:
Yes
Amber light on
Wait 2
Red light on
Wait 10
Red light off
Amber light flash
Wait 5
Green light on
No
Drawing Symbols
Drawings use many different line
types to show different parts of an
object.
 These are standardised so that
anyone can understand what is meant
by a particular line type regardless of
where they come from.

Drawing Symbols
Orthographic drawings are drawn in
Third Angle Projection.
 This is a standard drawing layout
covered in the tutorial on orthographic
projection where the 3 views are
drawn in the direction you are looking
at them.

Drawing Symbols
The 3rd Angle Projection symbol is
shown below.
 This is normally included on a drawing
to tell people the standard it is drawn
in.

Drawing Symbols

Different line types used include:
outlines
 projection lines
 hidden detail
 centre lines
 cutting planes
 fold lines

Drawing Symbols - Outlines
Outlines are used to show the outline
of an object.
 They are thicker than projection lines.
 Drawn at 0.7mm thick.

Drawing Symbols - Projection
Lines
Projection lines are used to help
construct a drawing.
 They are not part of the outline of the
drawing and are drawn lightly and
thin.

Drawing Symbols - Hidden
Detail
Hidden detail lines are used to show
any part of an object that cannot be
seen but does exist.
 They are dashed lines.

Drawing Symbols - Centre
Lines
Centre lines are used to show the
centre of circles or lines of symmetry.
 They are drawn as a series of long
and short dashes.

Drawing Symbols - Cutting
Planes




Cutting planes are used to show where an object
is cut in a sectional drawing.
The arrows tell us what direction the cut is to be
viewed.
The letters are the label of the section.
The ends of the cutting plane are drawn slightly
thicker than the rest of it.
X
X
Drawing Symbols - Fold
Lines

Fold lines are used to show where
surface developments should be
folded.
Building Symbols
Engineers need to use symbols to
show the different materials used in
building a house.
 This is law as when submitting
planning permission a company must
be able to prove the quality of the
houses or buildings they want to build.


Building Symbols

You need to know each of
these symbols shown.
When asked a question in
your exam you will have
to name each symbol with
the exact name shown
below.
Storyboards
Storyboards give step by step instructions
on how to operate something using
pictures to illustrate what is to be done at
each stage.
 Short statements further help the user
understand what to do.
 They are often found on change machines
and in electrical appliance instructions.

Storyboards
These are advantageous as a person does
not have to speak any specific language to
understand what to do.
 The written instructions are kept very short
which helps people who, for any reason,
cannot read things properly.
 Often the statements are also given in
many different languages to help
foreigners.

Building drawings
A number of different drawings are
required to be completed and
submitted to the local authorities when
developers want to build new
buildings.
 This group of drawings is called a
Project Set.

Project Set

A project set consists of a number of
different drawings including
elevations
 sketches
 sectional drawings
 schematic diagrams
 location plans
 site plans
 floor plans

Project Set
Elevations, sketches and sectional
drawings are required to view the actual
building.
 Schematic diagrams are used by
tradesmen to install any electrical circuit
work or plumbing and heating.
 Schematic diagrams use British Standards
symbols covered in these slides.

Location Plans
This type of drawing shows the
position of the new building in its
surrounding area.
 It is as if you are looking at the
building from an aeroplane above.
 It is normally drawn to a scale of
1:1250.

Location Plans

This is an example of a location plan.
Site Plans
This type of drawing shows the
building from closer in than a Location
Plan.
 It is like a bird is looking down at it.
 It shows the building in its immediate
surrounding area.
 It is normally drawn at a scale of
1:200.

Site Plans

This is an example of a site plan.
Floor Plans
This type of drawing shows the
internal layout of a building including
the materials used in the walls.
 Any electrical appliances fitted will
also be drawn like, radiators, electrical
sockets and switches.
 This type of drawing is normally drawn
at a scale of 1:50.

Floor Plans

This is an
example of a
floor plan.
Scale Drawings
Scale drawings are used to draw an
object to a proportion of its real size to
offer a real life size in proportion to
other scaled objects around it.
 They are particularly useful when
modelling an object.

Scale Drawings

There are a couple of things that
effect the size of scale used to show
an object.
1. The size of the object. (A smaller
object will probably be drawn to a
larger scale and visa versa)
 2. The size of the paper you are
working on.

Scale Drawings
Some examples of scales that are
drawn larger than the object in real life
are shown below:
 2:1 - 2 units on drawing = 1 in real life
 3:2 - 3 units on drawing = 2 in real life
 5:1 - 5 units on drawing = 1 in real life
 50:1 - 50 units on drawing = 1 in real
life

Scale Drawings
These scales can be worked out as
follows:
 3:2 = 3/2 as expressed as a fraction
 This means that the dimension x 3
then divided by 2 is the size of the
scaled length.

Scale Drawings
Worked example:
Write the dimension on
the right at a scale of 3:2
Scale is 3:2 therefore can be written as 3
2
 3 x 20
60
=
= 30
2
2
 The scaled dimension is 30mm
20

Scale Drawings
Some examples of scales that are
drawn smaller than the object in real
life are shown below:
 1:2 - 1 unit on drawing = 2 in real life
 2:3 - 2 units on drawing = 3 in real life
 1:50 - 1 unit on drawing = 50 in real
life
 1:2500 - 1 unit on drawing = 2500 in
real life

Scale Drawings
These scales can be worked out as
follows:
 1:50 = 1/50 as expressed as a fraction
 This means that the dimension x 1
then divided by 50 is the size of the
scaled length.

Scale Drawings
Worked example:
Write the dimension on
the right at a scale of 1:50
Scale is 1:50 therefore can be written as 1
50
 1 x 2000
2000
=
= 40
50
50
 The scaled dimension is 40mm
2000

Scale Drawings - Rules
If a scale is written with a larger
number first then the drawing is larger
than real life. E.g. 2:1 is double real
life size.
 If a scale is written with a smaller
number first then the drawing is
smaller than real life. E.g. 1:2 is half
real life size.

Bibliography


Pages 29–32 - Signs and symbols from ISO, The International
Language of ISO Graphical Symbols, 2013, ISBN 978-92-6710605-2.
BSI symbols taken from SQA website.