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EXPERIMENT-1
OBJECT-:Gear cutting in milling machine using indexing head.
TOOL REQUREMENTS-:
1-Column and Knee Type Milling Machine 2- milling cutter. 3-indexing head

4-, work piece 5- cutting fluid etc.

Theory-:
Milling machine is one of the important machining operations. In this operation the
workpiece is fed against a rotating cylindrical tool. The rotating tool consists of multiple
cutting edges (multipoint cutting tool). Normally axis of rotation of feed given to the
workpiece.
The cutting tool used in milling operation is called milling cutter, which consists of multiple
edges called teeth. The machine tool that performs the milling operations by producing
required relative motion between workpiece and tool is called milling machine.

CALCULATIONS-:

Gear Nomenclature
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Column and Knee Type Milling Machine

Base
It provides rest for all parts of milling machine including column. It is made of grey iron by
casting.
Column
It is a type of rigid vertical long box. It houses driving mechanism of spindle, table knee is
also fixed to the guide ways of column.
Knee
Knee can be adjusted at a height on the column. It houses the feed mechanism of the table
and other controls.
Saddle
Saddle is placed at the top of the knee. Saddle provides guide ways for the movement of
the table .

Table
Table rests on the saddle. It consists of „T‟ shaped slots for clamping the workpiece.
Movements of the table (feed motions) are given in very controlled manner be lead screw.
Overhanging Arm
Overhanging arm is mounted on the column and serves a bearing support for the arbor. This
arm is adjustable so that the bearing support may be provided near to the milling cutter.
There can be more than one bearing supports to the arbor.
Arbor
It holds rotating milling cutters rigidly and mounted on the spindle. Sometimes arbor is
supported at maximum distance from support of overhanging arm like a cantilever, it is
called stub arbor. Locking provisions are provided in the arbor assembly to ensure its
reliability.

Milling Front Brace Front base is used to adjust the relative position of knee and
overhanging arm. It is also an extra support fixed between the knee and overhanging arm
for rigidity.

Spindle Spindle is projected from the column face and provided with a tapered hole to
accommodate the arbor. Performance of a milling machine depends on the accuracy,
strength and rigidity of the spindle. Spindle also transfer the motive power to arbor through
belt or gear from column
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INDEXING HEAD

INDEXING METHOD

(a) Direct indexing (b) Simple indexing (c) Compound indexing (d) Differential indexing

Simple indexing
In this case worm and worm gear is first engaged. So one complete turn of indexing crank
revolves the workpiece by th revolution. Three indexing plates are used. These plates have
concentric circles of holes with their different numbers as described below 1 40

Divide 40 by the number of divisions to be done on the circumference of workpiece. This

gives movement of indexing crank.
Indexing crank movement = 40/N
N is the number of divisions to be made on the circumference of workpiece

We will select the hole circle of 18 holes. After each milling operation indexing crank will be
rotated by 1 complete circle and 12 holes in 18 holes circle. This way milling operation will
be done by total 24 times.
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Procedure- The gear milling operations based on universal indexing method.

1. The gear blank is mounted on an arbor which is supported b/w a dead centre and a live
centre in the indexing head.

2. The cutter is mounted on the arbor of the milling m/c.

3. The geometric centre of cutter must be aligned exactly 90 degree with the centre line of
the indexing head spindle.

4. The table of the m/c is moved upward until the cutter just touches the periphery of gear
blank.

5. The vertical feed dial is set to zero.

6. The table is then moved horizontally until the cutter cleaned the gear blank.

7. The table is then moved upward by an amount equal to the full depth of the gear tooth.

8. The vertical movement may be less if gear is to be cut in two or more pieces.

9. After this the longitudinal feed of the table is engaged. The gear blank moves under
the rotating cutter and a tooth space is cut.

10. After this the movement of the table is reversed so that the cutter again clears the
gear blank.

11. The gear blank is then indexed to the next position for cutting the second tooth space.

12. This procedure is repeated until all the teeth have been milled.

Result- We prepared a gear of given module and no. of teeth on milling m/c.

Precautions –

1. Distance b/w two consecutive gear should be measured carefully.

2. Revolution should be done very carefully.

3. Feed should be given slowly.

4. Cutting fluid should be used time to time.

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EXPERIMENT-2
OBJECT-: CORE PRINT MAKING USING WOOD TURNING LATHE.

TOOL REQUIRED-:

1-FLAT CHISEL 2-MORTISE CHISEL 3-FIRMER CHISEL

4-FIRMER GAUGE 5-OUTSIDE CALIPER 6-TRY SQUARE

7-HAND SCREW 8-CONTRACTION SIDE 9-PANEL PIN

10-KHAMHAR WOOD 11-WOOD TURNING LATHE

THEORY-:
CORE PRINTS
When a hole blind or through is needed in the casting, a core is placed in the mould
cavity to produce the same. The core has to be properly located or positioned in the mould
cavity on pre-formed recesses or impressions in the sand. To form these recesses or
impressions for generating seat for placement of core, extra projections are added on the
pattern surface at proper places. These extra projections on the pattern (used for producing
recesses in the
mould for placement of cores at that location) are known as core prints. Core prints may be
of horizontal, vertical, balanced, wing and core types. Horizontal core print produces seats
for horizontal core in the mould. Vertical core print produces seats to support a vertical core
in
the mould. Balanced core print produces a single seat on one side of the mould and the core
remains partly in this formed seat and partly in the mould cavity, the two portions balancing
each other. The hanging portion of the core may be supported on chaplets. Wing core print

is used to form a seat for a wing core. Cover core print forms seat to support a cover core.
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PATTERN-:

A PATTERN IS A MODEL OR THE REPLICA OF THE OBJECT (TO BE CASTED). IT IS

EMBEDDED IN MOLDING SAND AND SUITABLE RAMMING OF MOLDING SAND AROUND THE PATTERN IS
MADE. THE PATTERN IS THEN WITHDRAWN FOR GENERATING CAVITY (KNOWN AS MOLD) IN MOLDING
SAND. THUS IT IS A MOULD FORMING TOOL. PATTERN CAN BE SAID AS A MODEL OR THE REPLICA OF
THE OBJECT TO BE CAST EXCEPT FOR THE VARIOUS AL1OWANCES A PATTERN EXACTLY RESEMBLES THE
CASTING TO BE MADE.

TYPES OF PATTERN-:

1. One piece or solid pattern 2. Two

piece or split pattern
3. Cope and drag pattern 4. Three-
piece or multi- piece pattern
5. Loose piece pattern 6. Match
plate pattern
7. Follow board pattern 8. Gated
pattern
9. Sweep pattern 10.
Skeleton pattern
11. Segmental or part pattern
OBJECTIVES OF A PATTERN-:

1 Pattern prepares a mould cavity for the purpose of making a

casting.

2 Pattern possesses core prints which produces seats in form of

extra recess for core
placement in the mould.

3 It establishes the parting line and parting surfaces in the

mould.

4 Runner, gates and riser may form a part of the pattern.

5 Properly constructed patterns minimize overall cost of the

casting.
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6 Pattern may help in establishing locating pins on the mould and

therefore on the
casting with a purpose to check the casting dimensions.

7 Properly made pattern having finished and smooth surface

reduce casting defects.
Patterns are generally made in pattern making shop. Proper
construction of pattern and
its material may reduce overal1 cost of the castings.

WOOD TURNING LATHE

A general wood working lathe is shown in Fig. which resembles roughly to an engine
lathe. It consists of a cast iron bed, a headstock, tailstock, tool rest, live and dead centers
and drawing mechanisms. The long wooden cylindrical jobs are held and rotated between
the two centers. The tool is then fed against the job and the round symmetrical shape on
the jobs is produced. Scrapping tool and turning gauge are generally used as a turning
tool on a woodworking lathe.
PROCEDURE-:
1- Fix the rectangular khamhar wood between headstock and tailstock of wood turning
lathe (center lathe)
2- Job is make cylindrical using firmer gauge.
3- Mark on job using scale as the required dimensions.
4- Between two 15 mm collar cut the groove of 10mm depth and 80mm wide using firmer
chisel.
5- Using mortise chisel corner edges are make sharp and precise.
6- Finally the job is split in two parts by hacksaw.
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Precaution-:
1 Before starting any wood working machine, it should be
ensured that all the safety
guards are in proper places and secured well.
2 While working on a circular saw, one should not stand in a
line with the plane of
the rotating blade and always keep your fingers always away
from the reach of
blade.
3 The wooden pieces should not be fed to the sawing machines
faster than the cutting
speed of the machine.
4 While working on wood lathes, the job should be properly
held.
5 No carpentry tools should be thrown for saving time in
handling.

INDEX
NAME- YEAR- SEMESTER-

SUBJECTS- ROLL NO.-

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SR.N EXPERIMENTS EXPERIMENT DATE SUBMISSION SIGNATURE

DATE

1.
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