Page 33 - CITS - Fitter - Trade Theory

FITTER - CITS

Flat file
These files are of a rectangular cross section. The edges along the width of these files are parallel up to two-thirds
of the length, and then they taper towards the point.
The faces are double cut, and the edges single cut. These files are used for general purpose work. They are
useful for filing and finishing external and internal surfaces.

Hand file
These files are similar to the flat files in their cross section. The edges along the width are parallel throughout
the length. The faces are double cut. One edge is single cut whereas the other is safe edge. Because of the safe
edge, they are useful for filing surfaces which are at right angles to surfaces already finished.
Square file: The square file is square in its cross section.
It is used for filing square holes, internal square corners, rectangular openings, keyways and splines.

Round file
A round file is circular in its cross section.
It is used for enlarging the circular holes and filing profiles with
fillets.

Half round file

A half round file is in the shape of a segment of a circle. It is used
for filing internal curved surfaces.

Knife edge file
A knife edge file has the cross section of a sharp triangles. It is
used for filing narrow grooves and angles above 10º. The above
files have one third of their lengths tapered.
They are available both single and double cuts.

Triangular file

A triangular file is of a triangular cross section.
It is used for filing corners and angles which are more than 60o
.Square, round, half-round and triangular files are available in
lengths of 100, 150, 200, 250, 300 and 400mm. These files are
made in bastard, second cut and smooth grades.

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CITS : CG & M - Fitter - Lesson 3