Page 133 - CITS - Fitter Trade Pactical - Volume - 2

FITTER - CITS

EXERCISE 38: Exercise involving preparation of one of

the flat surface as master and two of the
adjoining sides square by filing flat and

square

Objectives

At the end of this exercise you shall be able to
• file surfaces flat and square within ±0.02mm using flat bastard and second cut file.
• scribe lines parallel to reference surfaces using a scriber.
• punch witness marks on scribed lines with a dot punch.
• check flatness and squareness using a try-square.
• check thickness using an outside caliper.

Job Sequence

• Remove burrs, if any, using a flat second cut file and ensure the metal surface is free from oil or grease.
• Check the raw material for its size with a steel rule 300mm.
• Hold the workpiece in a 125mm jaw bench vice on its ends.
• Ensure the work is held horizontally.

Do not over-tighten the workpiece.

• Remove the scaling surface using Rough file
• File the top surface with a flat bastard file 250mm.

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