Introduction to Engineering Drawing
as powerful means of communication with others for conveying
ideas on technical matters. an engineer should posses good
knowledge, not only in preparing a correct drawing but also
to read the drawing correctly.
These drawings are about machine parts.
2) Production Drawing–
A production drawing, also referred to as working
drawing, should furnish all the dimensions, limits and
special finishing processes such as heat treatment, honing,
lapping, surface finish etc., to guide the
craftsman on the shop floor in producing the
or part drawing is a detailed drawing of a component to
facilitate its manufacture.
4) Assembly Drawing– Detail
drawing of assembly.
Assembly Drawing, Sub- Assembly
Drawing, and Installation Assembly Drawing.
machine shop drawing frequently gives only the information
necessary for machining.
drawn in the patent report with details and assembly of a
parts. In this drawing numbers like 1,2,3,4 are given to Sub
scale reduction and enlargement. Scale is the ratio of the
linear dimension of an element of an object as represented in
the drawing, to the real linear dimension of the same element
of the object itself. Wherever possible, it is desirable to
make full size drawings, so as to represent true shapes and
sizes. If this is not practicable, the largest possible scale
should be used. While drawing very small objects, such as
watch components and other similar objects, it is advisable
to use enlarging scales.
How to Specify a Scale:
the word Scale, followed by the indication
should be shown in the title block.
The recommended scales for use on technical drawings
are given in Table. The scale and the size of the object in
turn, will decide the size of the drawing.
scale should be indicated in or near the title block. Where
it is necessary to use more than one scale on a drawing, the
main scale only should be shown in the title block and all
the other scales, adjacent to the item reference number of
the part concerned or near the drawings.
Tips for Dimensioning:
outside the view.
rather than from hidden lines.
except when the centre line passes through the centre of a
that relates most clearly to the corresponding
dimensions, but without showing the unit symbol.
part should be shown on a drawing.
more than one dimension in any one direction.