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What is Fitting:
Fitting means preparing matching parts to touch or join each other in such a way that one will turn
inside of another and one will slide upon another
or the part hold tightly together.
Processes in the Fitting Shop
Marking & Measuring
Fitting Shop Tools
Marking, measuring and testing tools
Marking, measuring and Testing tools
This type involves steel rule, meter rod,
trisquare, scribber, divider, calliper, surface
guage, drill guage, combination set, V
Block, surface plate
Cutting Tools This type involves files, drills, taps, dies,
reamers, hack saw, chizzles.
Holding Tools This type involves tools holding devices.
Examples are bench vise, machine vise,
pipe vice, leg vice and hand vise.
This type involves tools as ball peen hammer, cross peen hammer and
Cutting of a metal surface by using a specially designed tool, called a
file. A file (or hand-file) is a hand tool used to shape material by abrasion.
Classification of files Shape (Flat, round, square etc )
Grade (Rough, Bastard, Smooth etc)
Cut (Single cut, Double cut, Rasp cut etc)
Length ( Ranging from 4-18’’)
Files have forward-facing cutting teeth, which means
that the file cuts effectively only when pushed over the
work piece. Pulling a file over a work piece or
scraping a file back and forth is ineffective and will
reduce the life of the file.
The grooves in a file may become clogged during
use, causing the file to lose its cutting ability.
Files should always be used with a handle,
otherwise the naked tang can injure the operator.
Marking is done on the job to locate the exact point
where we have to carry out some other processes
like sawing, drilling etc.
In fitting shop marking is carried out with some
specified tools such as scribber, punches, hammer
The surface of the work piece is painted with lead oxide
(brown) and scribber is used to scribe marking lines on the
job. Marking line should not be more than .2mm wide
Then punching is done using punches and hammers.
Punching is done to locate the position for holes to be
Using specified tools measuring is done to check the
accurate dimensions of the W.P.
Sawing A saw is a tool for cutting wood or other material. it
consist of a blade with the cutting edge toothed. The teeth of the saw are each bent to specific angle and this angle is called "set".
TYPES OF SAW Hand saws: Hand saw is used manually for cutting
Mechanically powered saw: Mechanically powered saws mechanically move the teeth past the material while the saw itself is held stationary.
Sawing is done to produce thin cuts.
Hack Saw is a chief tool used, which is available in different types and sizes depending on the length of the blade and its cuts.
Normal dimensions of a blade = 250x12 mm2
Hacksaw teeth are specified by its pitch
( pitch=distance b/w two successive troughs or
Sawing Pitch of the teeth should give maximum clearance for
the chips and avoid clogging.( Normal pitch =
Sawing too sharply over a corner will result in teeth
being torn off.
What is a Drill? A tool or machine with a pointer for making
holes of different diameter.
Instruments Use for Drilling
1. Drill Chuck
2. Drill Chuck Key
3. Drill Drift
4. Sleeve OR Socket
5. Shank Twist Drill
STEPS OF DRILLING
Step 1. Use a scribe to scratch a line on
piece where we wanted hole.
Step2. Use a center punch and a hammer
to mark the spot because the punch
mark will hold the tip of the drill in place
until it begins to cut the metal.
Step 3. Drilling deep or large holes, it is
best to drill a small reference hole first.
Step 4. We will find a burr on the back surface of
drill hole. This can be removed by lightly drilling
the back side of the hole.
What Is Reaming? Reaming is a process which slightly enlarges a pre-existing
hole. Several cutting edges are arranged around a central
shaft. Its purpose is to finish the internal diameter of the hole.
Parts of Reamer