Page 223 - CITS - ED - Mechanical

ENGINEERING DRAWING - CITS

Fig 15 Fig 16

– the notation except where otherwise stated in Fig 17.
– a basic symbol (in brackets) without any other indication Fig 18.

Fig 17 Fig 18

– the symbol or symbols (in brackets) of the special surface roughness or roughnesses. (Fig 19)
The symbols for the surface roughness which are exceptions to the general symbol are indicated on the corre-
sponding surfaces.

To avoid the necessity of repeating a complicated specification a number of times, or where space is limited, a
simplified specification may be used on the surface, provided that its meaning is explained near the drawing of
the part, near the title block or in the space devoted to general notes. (Fig 20)

If the same surface roughness is required on a large number of surfaces of the part, one of the symbols shown
in Fig 1,2 & 3a may be used on the appropriate surfaces and its meaning given on the drawing, for example, as
shown in Fig 21a,b & c.

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CITS :Engineering Drawing (Mechanical) - Exercise 9