1

2

CHAPTER 1

INTRODUCTION

1.1 INTRODUCTION Mechanical engineering without production and manufacturing is

meaningless and inseparable. Production and manufacturing process deals

with conversation of raw materials inputs to finished products as per required

dimensions specifications and efficiently using recent technology.

CHAPTER 1 is the introduction chapter of this project. Generally, it discuss

about the project background, problem statement, the objective, scope of

project, projectflow and project Gantt chart.

1.2 BACKGROUND Imagine two plain wheels fixed rigidly to two parallel shafts and pressed

tightly in contact witheach other. If one wheel is rotated about its axis, the

other wheel will also rotate due to thefriction between them. The rotary

motion is thus transmitted from one shaft to another. Thesurfaces of the two

wheels will move at the same speed if there is no slipping. It is obvious that

with the increase in Load to be transmitted, the wheels will begin to slip on

each other.To prevent slipping slots may be cut on the cylindrical surfaces of

the wheels and projectionsadded between them. These slots and projections

form the teeth, and wheels with such teeth arecalled toothed wheels or gears.

3

Fig1.2.1 (Gear terminology)

1.3 PROBLEM STATEMENT Lathe is suitable for operations like turning, boring, facing taper turning,

thread cutting, knurling, etc. but not suitable for operations like key way

cutting etc. Because in a conventional lathe as soon as the machine is

switched on, the workpiece fixed to the chuck rotates. This is a major

limitation of the conventional lathe keeping in view of the present project

work.

Gear cutting is a specialized form of milling, and the lathe is quite suited to

this job for smaller work (6" diameter or so) with the help of attachment.

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1.4 OBJECTIVE The objective of this project is:

Our project design and fabrication of gear cutting attachment is used to cut

gear or splines over the cylindrical job.

Our main aim is to prove lathe as a versatile machine and with the help of gear cutting attachment the object is possible by lathe itself.

1.5 SCOPE

i. To cut gears without milling machine.

ii. To cut splines over shafts.

iii. To cut key ways & slots.

1.6 FLOW CHART

The project starts identify the problem. It is a first step for the project flow in

order tofind the problem in conventional lathe . This step helps to create a

different design to improve the product.After identify the problem for the

project, project continues with identify the objective. The objective is very

important in every work because every procedure to make a project will

depend on it. It will help to know the main point to make the project success

or not. The project continues with identify the scope of the project because

this scope can help the progress to create the new product design for the

project and to make sure the method chose will be within the range of

achievable objective. Next continue it with literature review and research

about the title. This consist a review of the design and type of safety. These

tasks have been done through research on the internet. From the flow chart,

start to design new concept. Use datum as reference. Then improve the

design. Try to come with several concepts. Then compare the criteria from

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each design which the most best. If the design chosen still needed to be

improved go back to the previous steps. If no improvement is needed go to

next step. Produce the drawing together with dimension of the product and the

type of material needed. After completing the previous task, start the

fabrication process. Gather the parts needed for the project to proceeds the

fabrication process. Here come the testing and evaluation process. During the

testing, if problem occur, the process of fabrication will step back to the

previous process. The reason to step back is to fix the error. After all part had

been joined together and no error, here comes the phase of result and

discussion. Beside, how to achieve objective and solve problem statement of

the project will be discuss in this phase.

Fig1.6.1 (flow chart)

6

1.7 GANTT CHART Gantt chart is an importance to guide work process during this project. With

gantt chart what need to be done first can be plan accordingly. Other than

that, this project will run smoothly and finish on time.

MONTHTaskData collection

Establish target

Basic darwing of componants

Assembly drawing and design

Analysis of Design

material selection

Fabrication of componants

Part assembly

Finishing

Design testing

Final presentation

Report

PlanningActual

february march aprilseptember october november december janurary

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CHAPTER 2

LITERATURE REVIEW

2.1 INTRODUCTION CHAPTER 2 is the literature review of the project. In this chapter, various

literatures on gear cutting attachment in lathe, basic principles which use for

fabrication of attachment, fabrication planning& machine used for fabrication

are described.

2.2 LITERATURE REVIEW

i.Keyway &GEAR-CUTTING ATTACHMENTS TO LATHES on Jan.

30, 1940 by T. E. SMITH. (USA Patent No. 2188447 A)–

First of all T.E.SMITH proposed the principle of gear and keyway cutting

attachment on lathe machine. He used a separate motor for rotating cutting

tool and indexing was done on lathe chuck. This attachment was very

complex and large in construction

ii.GEAR CUTTING ATTACHMENT by John w. Barons, Baltimore,

"Application Serial No.‘131,002 .” John w. barons Baltimore used screw for giving feed while T.E.SMITH used intermittent

feed device..

iii.MILLING ATTACHMENT FonLÀfrHEsJoseph C. Harbison, Eldorado, Ill.,

assignor offorty-three and onefthird per cent to . ObeRoberts, Eldorado, Ill.

Joseph c. Harbision eliminated the use of motor and replaced the chuck

indexing by compound indexing .Cutting tool was mounted on arbor and arbor

was mounted between chuck and tail stock

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2.3 BASIC PRINCIPLES GEAR PRODUCTION

Gears may be manufactured by casting, stamping, machining or by powder

metallurgical process. Out of all processes, the most common and accurate

method of production of gears is by machining. You are required to cut gears

on a Horizontal Milling Machine.Schematic diagram of this machine is given.

Fig 2.3.1

Cutting of a Spur Gear on a Milling Machine involves the following steps:

1.To determine the important dimensions and proportions of the gear tooth

element.

2.Mounting the cutter and the job on the machine.

3.Adjust the position of the table to the starting position.

4.Indexing.

5.Repeat the operation till the gear is complete.

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INDEXING

Indexing is an operation of dividing the periphery of a piece of work into any

number of equal parts, for e.g. this operation can be adopted for producing

hexagonal and square headed bolts, cutting spines on shafts, fluting drills and

in gear cutting. All these works require a holding device which will permit the

rotation of the work about the axis so that periphery of the work piece can be

divided equally and accurately. Such a work holding devices is known as DIVIDING HEAD OR INDEXING HEAD.

METHODS OF INDEXING:

i) Direct Indexing ii) Simple Indexing

iii) Compound Indexing iv) Differential Indexing

Direct Indexing: It is also called Rapid Indexing. This is used when a large

number of identical pieces are indexed by very small number of divisions.

Therapid plate is generally fitted to the front end of the spindle nose. The

plate has 24numbers of equally spaced holes. Into any one of which a spring

loaded pin is pushed to lock the spindle with the frame while indexing, the pin

is taken out and the spindle is rotated by hand. After the required position is

reached, it is again locked by the pin. Now the dividing head spindle and

work are also turned through the same part of revolution. With this type of

indexing with a plate of 24 holes, the periphery can be divided into

2,3,4,6,8,12 or 24 parts which are all factors of 24.

fig 2.3.2

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2.4 FABRICATION PLANNING & MACHINE USED IN

FABRICATION Lathe

A lathe is a machine tool which turns cylindrical material, touches a cutting

toolto it, and cuts the material. A material is firmly fixed to the chuck of a

lathe. The lathe is switched on and the chuck is rotated. And since the table

which fixed the byte can be moved in the vertical direction and the right-and-

left direction by operating some handles. In order to get an efficient process

and beautiful surface at the lathe machining, it is important to adjust a rotating

speed, a cutting depth and a sending speedas shown in Figure below. I plan to

use this process to reduce the diameter of the solid rod.

Fig 2.4.1 Fig 2.4.2

Milling

Milling is the most common form of machining, a material removal process,

which can create a variety of features on a part by cutting away the unwanted

material. The milling process requires a milling machine, workpiece, fixture,

and cutter. The workpiece is a piece of pre shaped material that is secured to

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the fixture, which itself is attached to a platform inside the milling machine.

The cutter is a cutting tool with sharp teeth that is also secured in the milling

machine and rotates at high speeds. By feeding the workpiece into the rotating

cutter, material is cut away from this workpiece in the form of small chips to

create the desired shape. Milling is typically used to produce parts that are not

axially symmetric and have many features, such as holes, slots, pockets, and

even three dimensional surface contours. For CNC milling machine, coding is

the important thing to run the machine. There are two ways to make a coding

that is using a simulator or master cam. CNC milling machine is more

accurate than conventional milling machine. Figure below is an example of

milling process. I plan to use conventional milling machine to produce head

holder for my project.

Drilling

There are many machines capable and used to drill, ream or thread holes in a

part. Drilling is the manufacturing process where a round hole is created

within a workpiece or enlarged by rotating an end cutting tool, a drill. Figure

below show the drilling process. I plan to use this process to make a hole for

screw and thread.

Welding

Welding is one of joining process that joint part together to be a product. In

faculty laboratory there has two type of welding that is metal inert gas

welding, MIG and arc welding. Arc welding uses a welding power supply to

create an electric arc between an electrode and the base material to melt the

metals at the welding point. They can use either direct (DC) or alternating

(AC) current, and consumable or non-consumable electrodes. While MIG

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welding uses high deposition rate welding process,wire is continuously fed

from a spool. MIG welding is therefore referred to as a semiautomatic

welding process. Figure below show the MIG welding process. I plan to use

this process to make a join between workpiece.

Welding(fig 2.4.3)

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CHAPTER 3

METHODOLOGY

3.1 INTRODUCTION CHAPTER 3 is the methodology has been used to make gear cutting

attachment in lathe. In this chapter, a project flow chart is defined. The

information that included is establishing target specification, Basic drawing

&design , Analysis of design , Selection of components as per suitability

Selection of material, Fabrication of components , Assembly & Testing . It

also allows others to replicate our study and run new and different studies that

are based on our methodology.

3.2 PROCESS FLOW

PHASES TITLE

Phase 1 Establish target

Phase 2 Basic drawing &design

Phase 3 Analysis of design

Phase 4 Selection of components as per suitability

Phase 5 Selection of material

Phase 6 Fabrication of components

Phase 7 Assembly & Testing

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3.3 PHASE 1

ESTABLISH TARGET SPECIFICATION After the investigation of the objective, criteria selection will be developed.

Criteria selection here means the criteria that what people will look on the

product. Our product is not available yet in the market, we can see that usual

machining workshop where lathe machine not use for gear cutting, they still

use conventional milling machine to gear cutting. Our product target is to sell

this product to this kind of workshop and for individual user.

This is the criteria that I had to use to the design product for the gear cutting

in lathe machine.

i. Easy to use ii. Safety iii. Light weight

iv. Nice design v. Low cost vi. Strong

3.4 PHASE 2

BASIC DRAWING & DESIGN CONCEPT The purpose of this project is to design the gear cutting attachment in lathe

machine. The motivation for this project is to make gear without bought extra

machine in workshop and reduce cost to done this process. So the new

product and design should have a mechanism which available to gear cutting

and hold on the carriage of lathe machine so that it move on lathe bad. It will

look more efficient and if people who use it, they could be interested in

product because of the design and function that not available in market yet.

This is the idea concept for new design of gear cutting attachment in lathe.

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Proposed basic drawings

Base plate drawing (3.4.1)

Side frames drawing (fig 3.4.2) slider with screw

16

Design of components

Design of base plate (fig 3.4.3)

17

Design of left side frame (fig 3.4.4)

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Design of right side frame (fig 3.4.5)

Design of slider with screw (fig 3.4.6)

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Design of shaft with indexing (fig 3.4.7)

Design of locating pin (fig 3.4.8)

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Design of top plate (fig 3.4.9)

Design of assembled attachment (fig 3.4.10)

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3.5 PHASE 3

ANALYSIS OF DESIGN Final parts and final assembly is analyzed by solid works software. We use

parameters of standard lathe machine and milling cutter for force analysis.The

analysis was done on the basis of –

Static force

Maximum principal elastic strain

Maximum shear stress

Von Mises elastic strain

Von Mises stress

Factor of safety

Force Calculations

There are two forces related to the milling cutter. one is cutting force and another is thrust.

According to the machine specifications,

P = Power = 1 kw

N = Speed of rotation of the spindle = 560 rpm

D = Diameter of the cutter = approx. 50 mm

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Therefore,using the formulae for cutting force

V = πDN / 60

P = F. V

Therefore,

F = P / V

Putting the above values in this equation, we get cutting force

F =680 N.

2. Thrust Force

To calculate the thrust force, following formula was used

Thrust force (th) = K * D * f^0.7 N

D =50mm

f = 0.5mm/min

N =560

K = thrust force constant = 42.35

Putting these values in the above equation, we get

Thrust force (th) = 1290 N

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Study Properties

Study name Study 1

Analysis type Static

Mesh Type: Solid Mesh

Solver type FFEPlus

In plane Effect: Off

Soft Spring: Off

Inertial Relief: Off

Thermal Effect: Input Temperature

Zero strain temperature 298.000000

Units Kelvin

Include fluid pressure effects from SolidWorks Flow Simulation

Off

Friction: Off

Ignore clearance for surface contact Off

Use Adaptive Method: Off

Units

Unit system: SI

Length/Displacement mm

Temperature Kelvin

Angular velocity rad/s

Stress/Pressure N/m^2

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Loads and Restraints

Fixture

Restraint name Selection set Description

Fixed-1 <baseplate-1> on 2 Face(s) fixed.

Load

Load name Selection set Loading type Description

Force-1 <nut-2> on 1 Edge(s) apply force 1290 N normal to reference plane with respect to selected reference Face< 1 > using uniform distribution

Sequential Loading

Force-2 <shaft-3> on 1 Face(s) apply normal force -680 N using uniform distribution

Sequential Loading

Contact

Contact state: Touching faces - Free

Global Contact Contact component: Bonded on gear cutting atachments

Description:

Component Contact-1 Contact component: Bonded on nut-1

Description:

Component Contact-2 Contact component: on baseplate-1

Description:

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Mesh Information

Mesh Type: Solid Mesh

Mesher Used: Standard mesh

Automatic Transition: Off

Smooth Surface: On

Jacobian Check: 4 Points

Element Size: 11.88 mm

Tolerance: 0.59399 mm

Quality: High

Number of elements: 9423

Number of nodes: 16542

Time to complete mesh(hh;mm;ss): 00:00:04

Computer name: Dushyant

Reaction Forces

Selection set Units Sum X Sum Y Sum Z Resultant

Entire Body N 674.682 -513.388 -1183.44 1455.78

Free-Body Forces

Selection set Units Sum X Sum Y Sum Z Resultant

Entire Body N -0.000866733 0.000642514 0.0014296 0.00179104

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Free-body Moments

Selection set Units Sum X Sum Y Sum Z Resultant

Entire Body N-m 0 0 0 1e-033

Study Results

Name Type Min Location Max Location

Stress1 VON: von Mises Stress

0.185681 N/m^2

Node: 11046

(79.976 mm,

27.6158 mm,

-147.677 mm)

5.36901e+007 N/m^2

Node: 11882

(-66.3766 mm,

-0.896929 mm,

-147.045 mm)

Displacement1 URES: Resultant Displacement

0 mm

Node: 32

(30.459 mm,

-13.8979 mm,

-9.63401 mm)

0.0936979 mm

Node: 11001

(-140.034 mm,

3.95554 mm,

-145.318 mm)

Strain1 ESTRN: Equivalent Strain

7.73579e-013

Element: 6289

(81.6661 mm,

18.116 mm,

-106.54 mm)

0.000176823

Element: 6243

(-65.899 mm,

1.46701 mm,

-145.064 mm)

Stress2 VON: von Mises Stress

0.185681 N/m^2

Node: 11046

(79.976 mm,

27.6158 mm,

-147.677 mm)

5.36901e+007 N/m^2

Node: 11882

(-66.3766 mm,

-0.896929 mm,

-147.045 mm)

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gear cutting attachment-static stress analysis (fig 3.5.1)

gear cutting attachment-displacement analysis (fig 3.5.2)

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gear cutting attachment-strain analysis (fig 3.5.3)

gear cutting attachment-Study factor of safety (fig 3.5.4)

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Conclusion

It is evident from the above simulation images that all the values of stresses and strain were in the permissible limits.The factor of safety of wholegear cutting attachmentis very high.

3.6 PHASE 4

SELECTION OF COMPONANTS AS PER SUITABILITY After the design and analysis, the best design is studied to relate it with

criteria selection. Then make decision which components are suitable. For

this project, As per the suitability of dimensions according to the lathe

machine designed the various parts which are the best after considering the

criteria selection.

3.7 PHASE 5

SELECTION OF MATERIAL After the analysis we specified the material of various components which use

in this project. For this project, I plan to use mild steel and galvanized iron.

Mild steel is used as body for main part in this project to hold the slider as

well as indexing plate support. Besides that, galvanize iron is use as a screw

with thread and in shaft which use for holding work piece with the help of nut

and collar. A spring of mild steel is also use which support locating pin.

Table below is the list of material that needed to fabricate this project. I chose

to use all this material because of the safety factor and all this material are

easily available.

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Material Properties No. Body Name Material Mass Volume

1 Slider with screw 1023 Carbon Steel Sheet (SS)

2.44255 kg 0.000310837 m^3

2 Shaft with indexing plate

1023 Carbon Steel Sheet (SS)

0.996566 kg 0.000126822 m^3

3 Base plate 1023 Carbon Steel Sheet (SS)

4.11032 kg 0.000523074 m^3

4 Side frame 1023 Carbon Steel Sheet (SS)

2.16095 kg 0.000275 m^3

5 Side frame 1023 Carbon Steel Sheet (SS)

2.16095 kg 0.000275 m^3

Material name: 1023 Carbon Steel Sheet (SS)

Material Source: Market

Material Model Type: Linear Elastic Isotropic

Default Failure Criterion: Max von Mises Stress

Application Data:

Property Name Value Units Value Type

Elastic modulus 2.05e+011 N/m^2 Constant

Poisson's ratio 0.29 NA Constant

Shear modulus 8e+010 N/m^2 Constant

Mass density 7858 kg/m^3 Constant

Tensile strength 4.25e+008 N/m^2 Constant

Yield strength 2.8269e+008 N/m^2 Constant

Thermal expansion coefficient

1.2e-005 /Kelvin Constant

Thermal conductivity 52 W/(m.K) Constant

Specific heat 486 J/(kg.K) Constant

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Hardening factor (0.0-1.0; 0.0=isotropic; 1.0=kinematic)

0.85 NA Constant

Part such as Screw, Nut, washer, and spring is available in the market.

3.8 PHASE 6

FABRICATION OF COMPONANTS

Base plate

Base plate cut by gas cutting of dimension 200x165x16 and than finishing is

done on grinding machine .Two hole of diameter 14 mm done by the vertical

drilling machine as shown in fig.

Side frames

First we cut the galvanized plate by gas cutting of dimension 200x140x16

then cut it into trapezoidal shape which have sides140mm ,200mm &

80mm.after this a groove of depth 7 mm is cut by the face milling machine of

width 55 mm. Side frame is shown in fig.

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Fabricatedbase plate with side frames

Slider with screw-

A block of dimension of 105x55x55 is cut by power saw and hole is done by

drill machine throughout 55 mm from center point .A screw of length 120

mm which consist Mx20x3 thread is weld on block at center.

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Fabricated slider with screw

Shaft with indexing plate

A shaft is of dia 25 mm is found after turning operation on lathe machine,

length of shaft is 225 mm which is found after cutting by power saw . A

counter turning is done on lathe of dia 20 mm and length 40 mm for

workpiece mounting .For Indexing plate ,we cut a circular plate of dia 70 mm

and 8 mm thick with the help of divider then finish it by surface grinder .Hole

on plate is done by drilling machine in circular way as shown in fig.

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Locating pin arrangement

Locating pin arrangement is done by a mild steel strip of length 230 mm and

3 mm thick.we gave the shape as shown in fig. by the hammer and anvil. Pin

and spring is available in the market.

Fabricated locating arrangement with slider and shaft

3.9 PHASE 7

ASSEMBLY & TESTING Assembly of gear cutting arrangement is done by welding mainly. Side

frames are welded on base plate .The lead screw is fixed on slider by welding

it and a cover plate on the top of the side frames is welded for providing

proper alignment and stability to lead screw. locating pin arrangement is

welded on slider in the side of indexing plate . a compression spring is used

on the pin for getting the pin tightened in desired hole of indexing plate at the

time of operation .Washer and nut are used for the arrangement of this spring

35

A tapping pin is provided for preventing the movement of the shaft in the

slider hole while cutting gear

The tool post on lathe machine is replaced by this whole assembly and a work

piece is mounted on shaft by nut and at moderate speed and low feed rate gear

is cut successfully.

36

ATTACHMENT ASSEMBLY (fig7.1)

37

Atachment mounted on lathe (fig 7.2)

38

CHAPTER 4

RESULT AND DISCUSSION

4.1 HOW TO USE THIS Firstly, remove the tool post from lathe carriage and mount this attachment in

place of tool post. Adjust the cutter tool arbor between chuck and tail stock.

Get the workpiece tightened on the mount shaft with the help of nut. Start the

lathe machine. Feed is given by cross slide and depth is given by screw on

slider.

4.2 HOW THIS PROJECT ACHIVES THE OBJECTIVES

The foremost and primary purpose to cut the gear is satisfactorily achieved with good accuracy. The attachment has build and cutting is to be tested.

By providing gear cutting attachment on the lathe machine ,lathe becomes more versatile.

4.3 BENEFITS AFTER MOUNTING THE ATTACHMET

i. The attachment is to be used on lathe for gear cutting.

ii. It is a simple and low cost device.

iii. With some improvement, it can be used for precision cut and finish.

39

CHAPTER 5

CONCLUSION AND RECOMMENDATION

5.1 CONCLUSION We know that Country’s GDP is largely affected by many small scale

industries. Also, we saw that in this fast moving world a micro industries are

facing very tough competition from large scale industries and it’s almost very

difficult for them to survive and earn their share of bread and butter as they

have an only choice of selecting one or two machine at a time due which there

is a rise of a serious problem called as either sub contraction or renting of

machines which further decreases the overall efficiency of whole machine

and industry. By selecting and incorporating such small but useful ideas a

small scale industrialist can save huge amount of time, energy, and money

hence forth increasing the overall productivity of a firm and hence

contributing more efficiently in countries GDP.

5.2 RECOMMENDATION If direct indexing is replaced by compound indexing then the limitation of

cutting specific number of teeth can be eliminated and we can cut any no of

teeth on gear.

If use of bush come into picture in slider’s hole then wear and tear of shaft

can be minimized upto a commendable level and so life of shaft as well as

slider will increase.

40

REFERENCES: 1.Designing and Fabrication of Multipurpose Tool Post for Lathe Machine

(IJSRD/Vol. 2/Issue 03/2014/033).

2.IMPROVEMENT IN GEAR-CUTTING ATTACHMENTS FOR

LATHES.(Specification forming part of Letters Patent No. 208,491, dated

October 1, 1878 ;application filed March 1l, 1878).

3.MILLING ATTACHMENT FonLÀfrHEsJoseph C. Harbison, Eldorado,

Ill., assignor of forty-three and onefthird per cent to .Obe Roberts, Eldorado.

(Application January 17, 1946, Serial No. 641,783)

4.THOMAS O. MILLS, OF ROGKFOItI), ASSIGNOR OF ONE-HALF ÍHIS

RIGHT TOWILLIAM H. MILLS, OF FREEPORT, ILLINOIS.

(IMPROVEMENT IN GEAR-CUTTING ATTACHMENTS )

(Patent No. 144,214, dated November 4, 1873)

5.Richard A. Maker (1993) “Milling machine lathe attachment” Application

number : US 08/002,967.

6.Production technology by R.K.Jain & Workshop technology by Hajariya

Chaudhry.

7. Wikipedia and GOOGLE SCHOLAR.