Page 243 - CITS - ED - Mechanical

ENGINEERING DRAWING - CITS

EXERCISE 10 : Reading of Engineering Drawing

Reading of Engineering

The heading "Blue pring reading" given in the syllabus is nothing but reading of engineering drawing.
In order to manufacture an engineering component, the shape of the component must be understood in unmis-
takable terms and those who are associated with the manufacture must be able to visualise the component from
its multi-view drawing.
Multi-view drawing has no 3D effect and do not convey the shape of a component in the first sight itself.
There is no one set of rules to read and visualise the shape of an object from the given multi-view drawing. Visual-
isation is essentially the reverse of the mental process that is gone through for obtaining the shape of the object.
In this reading of engineering drawing, different styles of exercises are given to improve the visualisation ability.
Sufficient "Reading of engineering drawing"
Finding/Sketching the missing
– lines
– views
– symbols
– sections etc.
When it is difficult to form a mental image of the object from the available views, one can resort to modelling by
means of isometric sketching. This can be done in many ways.
Example
Sketch/Draw the missing view of the block shown in Fig 1.
First sketch the isometric view of a rectangular block keeping in mind the overall length, breadth and height from
the views. (Fig 2a)
Then draw its isometric view by cutting away the portions of the prism drawn as required till we satisfy with the
outcome. (Fig 2b & c)
Instead of cutting away, we can also form the object by adding or joining portions together Fig 3a,b & c.

After sketching the final isometric view, missing view or line or anything can be found out easily.

Fig 1 Fig 2

Fig 3

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CITS : Engineering Drawing (Mechanical) - Exercise 10