3 eso tecnologies drawing
TRANSCRIPT
Unit 1.Drawing applied to technology
What are we going to see in this unit?1.1 Drawing materials and
instruments1.2 Drafts and sketches1.3 Drafting scale1.4 Diedric system1.5 Marking and standardizing1.6 Perspective systems
Unit 1.Drawing applied to technology
1.1 Drawing materials and instruments
PaperPaper is made of cellulose that is obtained
from trees The paper size that we use is A4 . It is the
result of dividing 1 m2 (A0) four times by half the longest side.
1.1 DRAWING TOOLS
THE RULERIt is a precision tool that makes it possible to measure and to transfer a distance.
TRIANGULAR SET SQUARE A set square is a tool for drawing perpendicular (vertical) and parallel lines and for obtaining angles. There are 2 types of trianglular set squares
A 45 degree
A 60 degree
1.1 Drawing materials and instrumentsHow to draw vertical and parallel lines
with the set square
Vertical: Parallel:
Activity: Draw the set squares in your notebook as you can see
them in both positions
1.1 Drawing materials and instruments
Drawing angles: we can get 15º, 30º, 45º, 60º, 75º, 90º, 120º, 135º…angles
combining the 30º, 45º , 60º and the 90º angles from the set squares
You don't have to copy them because you can find them in your text book on page 25
1.1 Drawing materials and instruments
Drawing angles exercise: you have to obtain, 45º, 75º, 90º, 120º angles
combining the set squares
Solution
1.1 DRAFT AND SKETCH
DRAFT: It is a free hand drawing (just with a pencil). We show an idea or object without totally defining it.
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1.1 DRAFT AND SKETCH
ATTENTION! A DRAFT IS NOT A BAD DRAWING AND A SKETCH IS NOT A GOOD DRAWING !!!!!!
1.1 DRAFT AND SKETCH
The sketch: It is a free hand drawing too, but it includes the measures, therefore it shows the precise size and a shape similar to the final drawing.
measure
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1.3 Drafting scale
We define scale as the relation between the drawing size and the real object
A model uses a reduction scale
1.3 Drafting scale
1:2
The Drawing
size
The Real size
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1.3 Drafting scale
1200 reality1cm drawing
1:1200
1 cm measured on the drawing is equivalent to 1200cm in reality
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1.3 Drafting scale
Scale types:• Reduction scale: it is used to
represent big objects, so they can be drawn on paper– We usually use: 1:2 1:5 1:10…
In this example we have reduced 1000 times the real size of the tree
1:1000 Realdrawn RealReal
1.3 Drafting scaleEnlargement scale: it is used to
represent small objects so we can see them on paper
– It is used: 2:1 5:1 10:1 …
In this example the drawing is two times the real object
2:12:1
Drawing
Real
Safety pin
1.3 Drafting scale
An example of scale application• Let’s draw a pencil that is 10cm
high and 1cm wide using different scales: 2:1, 1:2, 1:41cm
10cm
1.3 Drafting scale
Scale 2:1
High wide
Drawn
Real 10 1
Real
2:1
1.3 Drafting scale
Scale 1:2
High wide
Drawn 1
Real 2 10 1
2:1
Real
1:2
1.3 Drafting scale
Scale 1:4
High wide
Drawn 1
Real 4 10 1
Real
2:1
1:2
1:4
Real
2:1
1:2
Real
1:2
2:1
Real
1:2
1.3 Drafting scale
Scale exerciseUsing an electronic microscope we can see a virus that is 1,5pm. This picture is 6 cm long, do you know the scale used to draw it?
1.3 Drafting scale
Scale ???:1
Long
Drawn ????? 6 1010pm
Real 1 1,5 pm
1.4 Diedric system
1.4 Diedric system
The diedric system represents the objects using a perpendicular projection on a plane
1.4 Diedric systemThe projection or VIEW consists of drawing just what we see when we are perpendicular to the object and to the plane
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1.4 Diedric system
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1.4 Diedric system
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1.4 Diedric systemTo define an object we only need 3 views, floor, front
and profile:Floor view: from the top of the objectFront view: facing the objectProfile view: from the side
Profile view
Floor view
Front view
Front view
Floor view
Profile view
1.4 Diedric system
Diedric RulesThe front is usually indicated with an
arrowThe views distribution
The front is always on top of the floorThe profile is situated the other way around,
that is, the left profile is situated on the rightfront
floor
Left profile
Right profile
floor
front
1.4 Diedric systemRemember:The same height: the object has the same height on
the floor and on the profile viewsThe same width: on the front and on the floor viewsThe same depth: on the floor and on the profile
views
1.4 Diedric systemExercise: Draw the front, left profile
and floor views of the class chair. This chair is 80 cm high, 40 cm wide and 40 cm deep. Use the proper scale
1.4 Diedric system
Where do we have to be situated to see these objects like circles?
1.4 Diedric systemExercise 11: Complete the views of the following objects
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1.4 Diedric system
Non visible lines: when we know there is a hidden line we have to draw it using a discontinuous line
hidden line
1.4 Diedric system
Activity: draw the front, floor and left profile views of this figure coloring each face in one color. Apply a proper scale
30cm
100cm
100cm
20cm
1.4 Diedric system
Exercice: draw the right profile, front and floor views of these objects
100cm
1.5 Marking and standardizingThe standardizing is the group of
rules that define objects in technical drawing.
1.5 Marking and standardizingUsing a standard language we can define the size, materials and properties of an object so that anyone can read it
1.5 Marking and standardizingThere are several elements used to draw a object, but we are going to see only the most relevant:
1.PaperFor paper size we use the DIN rule: A0,A1,A2…
1.5 Marking and standardizing
2.- Lines
The lines are:Thick continuous lines: are used to outline objectsThick discontinuous lines: indicate hidden linesThin continuous lines: are used for auxiliary measures
and reference lines.Dots and thin discontinuous lines: indicate a
circumference or cylinder axis
1.5 Marking and standardizing
Measure line
Auxuliary Line
Measure
Circumference axis line
Reference line
1.5 Marking and standardizing
Marking : indicating the real dimensions above the object
1.5 Marking and standardizing.
The measure lines: We place them parallel to
the edge and slightly separated
They are limited by the auxiliary lines
The arrows are thin and elongated, they go from one side to the other
Marking follows some rules
1.5 Marking and standardizing
Auxiliary linesWe place them
perpendicular to the measure lines
They cross the measure line a little bit
They never cut the measure line
1.5 Marking and standardizing
The measures:We indicate the real
measure in milimetres, but “mm” is never written
They are placed above the measure line, never under it
We only use the extrictly necessary measures
Measure line ends
Arrow: ends in a aux. Line
Line: ends in a measure line
Dot: ends in a line objectMeasures position
1.5 Marking and standardizing
Activity: draw these views indicating which rules are broken
Correct Wrong
Exercice: Make a file of this object, drawing its views including all measures, AND SCALE
Assembled sizeWidth: 79 cmWood widht: 5 cmDepth: 39 cmHeight: 79 cmMax load/shelf: 13 kg
1.6 Perspective systems
Which one of these objects is a cube?
1.6 Perspective systemsThey are all cubes,
but drawn with different
perspectives
1.6 Perspective systemsBut, what is a perspective?It is an approximate representation, on a flat surface (such as paper), of an image as it is perceived by the eye.
1.6 Perspective systemsThe simplest one is the one point perspective, where all
lines go to one vanishing point
Vanishing Point
Video link
Acceso directo a 1punto habitacion.lnk
1.6 Perspective systemsIf we want to create a more realist drawing we have to
use a two point perspective
Now we have two vanishing points, where the left and right lines go
1.6 Perspective systemsFinally, we have the three points
perspective, that creates an almost real view
Lines go to the left, the right and the floor
vanishing points
1.6 Perspective systemsRegular objects are drawn using the
caballera perspective
All lines are parallel to Z, X
or Y axes
1.6 Perspective systems
X and Y axes form a 90º angle and Z axe form a 135º angle
Z axe
Y axe
X axe
90º
90º
135º
1.6 Perspective systemsIn X and Y axes measures are applied directly. But, in order to create a human vision of the object, Z axe form a 135º angle and measures have a ½ reduction
½ reduction in all z measures
1.6 Perspective systems
Exercise. You have to present the standard file of this object that has to describe the scale used, measures, views and caballera perspective.
Measures: Assembled sizeWidth: 79 cmDepth: 39 cmHeight: 149 cmWood width: 5 cmMax load/shelf: 13 kgStandard File Data:Name and Family nameGrade and GroupScale and unitsName of the file and short description