UNIT 2:Graphic expression

Unit 2

Graphic expression

Representation systems

Summary

1. Introduction

2. Cavalier perspective

3. Isometric perspective

4. Drawing in perspctive

5. Standardisation and annotation

6. Measuring instruments

7. Scales

Key vocabulary

Nouns

Verbs

Adjetives

length, scales, standardisation, lines, annotation, axis, height, depth, angles, edge, freehand, viewpoint, overhead, elevation, profile or side view. Radius, diameter, arrow, plane, ruler, grid

Sloped (angle), squared (paper), dotted (lines), surplus, reducing, enlarging or full-size (scale), hidden (edge), fine, thin, thick (lines)

Measure, standardise, locate, section, dimension, snap

• Diameter
• Plane
• Radius
• Arrow
• Depth
• Scales
• Lenght
• Lines
• Overhead
• Freehand
• Axis
• Angle
• Standarization
• Edge
• Elevation

• Cavalier
• Isometric

Perspectives

• Scales
• Standar lines
• Annotation

Standardisation

Measuring instruments

• Precise to a milimetre
• Precise to less than one

milimetre

perspectives

graphic expression

what are perspectives?

3D figures are projected onto a plane

Perspective cavailer

FRONT VIEW

LEFT SIDE VIEW

There are 3 axis of reference (2 in conical perspective)

Perspective Isonometric

views in an object

The main diference between perspectives are an angle between axis.

TOP VIEW

Perspective cavalier

1.- Analize the orthographic projections given ( front, side and top views) 2.- Draw the axis 3.-Draw the projection in thecorrect drawing https://www.youtube.com/watch?v=aYSbGjoJt9M

+ info

Isometric Perspective

.- Exercise papercraft. .- Practical exercise: https://www.youtube.com/watch?v=LY5OqKhEP9k

.- Angle between axes 120º .- Project front view - No reduction in the axes.

Drawing in perspective from an objects known viewpoints

Remark the final object

Analyse the views

Draw the axes

Draw a cube if it helps you

Project the views in the cube

standarisation and scales

graphic expression

Standarisation & annotation

Globalization

• There are rules related to technical drawing.
• They are used to ensure common understanding and impmentation of graphic expressions.
• Standard drawings are predefined drawing templates that contain standard notes and details.
• They are used in the design of construction projects to save time and effort.

When we use scales

Magnification

Reduction

An object is drawn smaller than reality

Real object is smaller than drawed.

VS

What are the scales

• A scale is the relation between drawing dimension an real objet dimension.

The sclae is defined with 2 numbers.

1:10

Reduction scales:

10 MEASURING UNIT OF THE REAL OBJECT

each 1 MEASURING UNIT OF THE DRAWING

What are the scales

1:10

Reduction scales:

10 MEASURING UNIT OF THE REAL OBJECT

each 1 MEASURING UNIT OF THE DRAWING

In the real world, one meter is equal to one meter. A drawing at a scale of 1:10 means that the object is 10 times smaller than in real life scale 1:1. You could also say, 1 unit in the drawing is equal to 10 units in real life.

1:10 Unit in the drawing : Unit in real life

Scales exercises

1.- Real width the road is 24 meters. Drawing scale is 1:200, ¿How many milimeters ill have the drawing? Soluction: 120 mm 2.- Which is the scale of the drawing of this building, if it is known that main door widht is 3.40 m and value of the drawing is 68mm. Solution: 1:50 3.- In a map drawing with a scale of 1:50.000, The distance measured with the rule is 45 mm. Which is the real distance in kilometers between the two villages? Solution: 2,25 Km

• 340 cm/6.8 cm

• 1 : 50.000
• 45 : X X=50.000*45 /(1000000

Drawing and measurement tools

graphic expression

Paper

Ruler

Drawing Tools

Toolbox

Pencil

Drawing Tools

Scale

Euismod tincidunt

Ruler

Drawing Tools

Drawing Tools

Drawing Tools

Drawing Tools

Drawing Tools

Drawing Tools

Drawing Tools

Drawing Tools

Drawing and Measuring instruments

https://www.youtube.com/watch?v=FNdkYIVJ3Vc https://www.youtube.com/watch?v=2-cm_ocn9p4

Drawing and Measuring instruments

Subtítulo

*Esescala de Vernier​​ es una segunda escala auxiliar que tienen algunos instrumentos de medición, que permite apreciar una medición con mayor exactitud al complementar las divisiones de la regla o escala principal del instrumento de medida.

https://www.youtube.com/watch?v=FNdkYIVJ3Vc https://www.youtube.com/watch?v=2-cm_ocn9p4

Precission Measuring Tools

VS

MICROMETER https://www.youtube.com/watch?v=2-cm_ocn9p4

CALLIPER https://www.youtube.com/watch?v=FNdkYIVJ3Vc

Dimensioning

Standarisation kind of lines

Dimensioning

Dimensioning Process

Dimensioning Process

Dimensioning

Dimensioning

Dimensioning

Dimensioning

Define the geometric and measuring of the object

Dimensioning elements:

Dimensioning value

Dimensioning line

Auxiliary line

Arrow

Reference line

Dimensioning

Rules for dimensioning

NOK OK

Dimension lines must be outside the contour of the piece

Dimension lines cannot coincide with drawing lines

Radius dimension lines cannot be horizontal or vertical

Rules for dimensioning

NOK OK

Dimension lines must be parallel to the contour of the figure

Dimension lines cannot coincide with drawing lines

Dimension lines and extension lines must not intersect the drawing

Rules for dimensioning

NOK OK

The arrow must to be inside the dimensioning line, if the dimensioning value doesn´t fit you can draw outside

All dimensioning must appear in the most representative view

Dimesions can not be repeated.

+ info

Rules for dimensioning

NOK OK

Smaller dimensions will appear nearer of the object than bigger dimensions

Dimension´s quiz

Dimensioning examples:

Dimensioning examples:

Dimensioning exercises

Dimensioning exercises

VIEWS

graphic expression

Introduction

What are the views of an object?

The object views are drawings of an objects form diferents perspectives. The 3 representative views are: Front view ( If we see the object in front of the object) Right view Top view (how the object is if we see from the top) We are going to use the European system that order in a diferent way the views in relation with american system.

FRONT VIEW RIGHT VIEW TOP VIEW .

Introduction

What are the views of an object?

https://www.youtube.com/watch?v=xPj2qBLnbi4 https://www.youtube.com/watch?v=IfcXpWbHyYc How can we draw them? https://www.youtube.com/watch?v=lO8PhvaRKsIc

+ info

There are 2 representative view systems: European & American 1.- EUROPEAN SYSTEM:

https://www.youtube.com/watch?v=HNlsbYi_Uvc

There are 2 representative view systems: European & American 1.- AMERICAN SYSTEM:

https://www.youtube.com/watch?v=HNlsbYi_Uvc

There are 2 representative view systems: Same object, same views diferent position

How to draw the views acording the European system:

How to draw the views acording the European system:

Examples:

Examples:

Unit summary

Measuring and Drawing Tools

Views

Scales

Dimensioning

Thank you!