Design Of Mini Milling Machine.docx

Design and Manufacturing of Mini Milling Machine

CHAPTER 1 INTRODUCTION 1.1 General: In this century, we have seen many new developments in very advanced manner at various fields. Many new products, machines have been innovated with available technology and other resources. In future it may be further developed in advance manner. Before selecting this mini milling machine as our project work, we have dealt in several fields related to mechanical for selecting a better project work But we hope that by doing this mini milling machine as our project work in a successful manner it may helps us in future to carry out different works. This machine we have manufactured is set to be the father of all machine tools. By the help of this machine, various operations can be performed. Various types of milling machines are available in the market but the machine manufactured by us is highly economical in all aspects i.e. the cost of manufacturing is less; more number of operations can be performed. It is compact in size; It occupies only less area; It can be operated manually even by an unskilled labour; this machine can be modified into a Semi-Automatic and Automatic milling machine by changing and fixing some of the necessary components. Initially it was made up of mild steel but now we have seen different types of milling machines. The most advanced type of milling machine is NC and CNC milling machines which are fully automatic and is numerically controlled by feeding dates and programming is done for various operations to be performed in the Job. A milling machine is a machine tool used for the complex shaping of metal and other solid materials. Its basic form is that of a rotating cutter or end mill which rotates about the spindle axis (similar to a drill), and a movable table to which the work piece is affixed. That is to say, the cutting tool generally remains stationary (except for its rotation) while the work piece moves to accomplish the cutting action. Milling machines may be operated manually or under computer numerical control.

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Design and Manufacturing of Mini Milling Machine

Milling machines can perform a vast number of complex operations, such as slot cutting, planning, drilling, rebating, routing, etc. In our project is deals with smaller operation using mini milling machine. Milling can be done with a wide range of machine tools. The original class of machine tools for milling was the milling machine (often called a mill). After the advent of computer numerical control, milling machines evolved into machining centres (milling machines with automatic tool changers, tool magazines or carousels, CNC control, coolant systems, and enclosures), generally classified as vertical machining centres (VMCs) and horizontal machining centres (HMCs). The integration of milling into turning environments and of turning into milling environments, begun with live tooling for lathes and the occasional use of mills for turning operations, led to a new class of machine tools, multitasking machines (MTMs), which are purpose-built to provide for a default machining strategy of using any combination of milling and turning within the same work envelope. The advantages of mini milling machine is that small components are easily machined, operating cost is less, more number of operations are performed, production time is less, unskilled person can also use it, simple mechanism is used, occupies less space while the disadvantages are complex parts cannot be machined. 1.2 Milling Processes:

Fig.No.1.1 Face Milling Process (Cutter Axis is Vertical) Milling is a cutting process that uses a milling cutter to remove material from the surface of a workpiece. The milling cutter is a rotary cutting tool, often with multiple cutting points. As opposed to drilling, where the tool is advanced along its

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Design and Manufacturing of Mini Milling Machine

rotation axis, the cutter in milling is usually moved perpendicular to its axis so that cutting occurs on the circumference of the cutter. As the milling cutter enters the workpiece, the cutting edges (flutes or teeth) of the tool repeatedly cut into and exit from the material, shaving off chips from the workpiece with each pass. The cutting action is shear deformation; material is pushed off the workpiece in tiny clumps that hang together to a greater or lesser extent (depending on the material) to form chips. This makes metal cutting somewhat different (in its mechanics) from slicing softer materials with a blade. The milling process removes material by performing many separate, small cuts. This is accomplished by using a cutter with many teeth, spinning the cutter at high speed, or advancing the material through the cutter slowly; most often it is some combination of these three approaches. The speeds and feeds used are varied to suit a combination of variables. The speed at which the piece advances through the cutter is called feed rate, or just feed; it is most often measured in length of material per full revolution of the cutter. There are two major classes of milling process: 

In face milling, the cutting action occurs primarily at the end corners of the milling cutter. Face milling is used to cut flat surfaces (faces) into the workpiece, or to cut flat-bottomed cavities.



In peripheral milling, the cutting action occurs primarily along the circumference of the cutter, so that the cross section of the milled surface ends up receiving the shape of the cutter. In this case the blades of the cutter can be seen as scooping out material from the work piece. Peripheral milling is well suited to the cutting of deep slots, threads, and gear teeth.

1.3 Problem Statement: The aim of our project is to design & manufacturing of mini-milling machine to reduce the time required for milling small parts as well as to reduce set up time for milling and increasing production rate.

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1.4 Project Objectives: General objective of this project is to develop a mini-milling machine up to industrially acceptable precision and repeatability with a very limited budget (10,000 RS).This newly designed mini milling machine is used to either reduce cost or improve performance. In addision to cost reduction this machine can be used to reduce set up time for operations and increasing production rate. This project represents all process for developing mini milling machine from early stage to performance stage. To accomplish these objectives, this project work is divided into a number of tasks. The tasks can be summarized as follows: (1) Market analysis: Determine the current market status of small scale machine tools and predict the market potential of the new small scale CNC machine. (2) Machine design: Various structure designs will be compared and analyzed to come up with an optimal structure for the machine. Critical components required such as motor and linear guides will be carefully compared and selected. (3) Machine fabrication: All the body parts will be machined and the components will be purchased through various suppliers. Machine will be assembled inside the workshop. (4) Machine test and calibration: The finished prototype machine will be tested using circular testing method. (5) Total machine cost will be analyzed. 1.5 Project Scope: (1) Design of various components of mini milling machine i.e. bed, spindle, column, lead screw, overhanging arm. (2) Selection of material for different components. (3) Manufacturing of different parts as per process sheet. (4) Assembly & testing

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1.6 Methodology: START

Literature Review

Data Collection & System Design

Selection of Material & Mechanical Design

Process planning & Material Procurement

Manufacturing & Assembly-Test &Trial

Report Preparation

END

Fig.No. 1.2 Methodology of Project

1.5.1 Literature Review: In this phase analyse the work done by previous researchers and find out scope for work. 1.5.2. Data Collection & System Design: Data collection phase involves the collection of reference material for project concept; the idea is taken from book ingenious mechanisms for designers and inventors.

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The system design comprises of development of the mechanism so that the given concept can perform the desired operation. The system design also determines the system components and their shape and overall dimensions, the parts are as shown in the list. 1.5.3 Selection of Material & Mechanical Drawing: Select the materials for different components by considering various factors, explained in subsequent section. The parts mentioned in list will be designed for stress and strain under the given system of forces and appropriate dimensions will be derived. The standard parts will be selected from PSG design data handbook. 1.5.4. Process Planning &Material Procurement: Material is procured as per raw material specifications and part quantity. Part process planning is done to decide the process of manufacture and appropriate machine for the same. 1.5.5 Manufacturing & Assembly-Test & Trial: Parts are produced as per the drawings. Assembly of device is done as per assembly drawing and test and trial is conducted on device for evaluating performance. 1.5.6 Report Preparation: Report preparation of the activities carried out during the above phases is done. 1.7 Organization of Dissertation: The project is presented in seven chapters including introduction, literature review process sheets, cost analysis and conclusion with further modifications. The introduction chapter, which is chapter one, will describe the background for the idea of mini milling machine. The project objectives and scopes have also been declared in this chapter. This chapter also shows the methodology of the project to be completed.

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The chapter two covers the literature review on the researches currently done on the mini milling machine. Some of the literature review shows the selection of optimum parameters for mini milling machine and some literature review shows analysis of structure of machine. The chapter three covers the factor considered for designing the components, specifications of mini milling machine, design of lead screw. It also includes selection of different material for different components of mini milling machine and properties of material. The chapter four covers different operations performed on different components of material and it also includes process sheet, which shows the sequence of operations performed on the material and time required for different operations. The chapter five represents the procedure for performing different operations on mini milling machine. The chapter six covers experimental result, analysis procedure and analysis of different components. The chapter seven covers total cost including cost of standard part. For manufactured part time required for manufacturing is taken from the process sheet and cost is calculated for each and every component. Finally total cost is summation of manufacturing cost, cost of standard parts purchased, accessories cost and miscellaneous cost. Conclusion and future scope included in chapter eight and finally report ends with chapter nine which is reference.

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CHAPTER 2 LITERATURE REVIEW In order to know the current state of art in domain of mini milling machine literature review is undertaken. Also the literature review will be useful to identify the gap to be bridged through this work. 2.1 A Review of Usability of Portable Milling Machine From Micro To Macro Parts By Krishna Dave,Marnish Modi,Prof.A.N.Shyani. From above research paper, the following points are observed: 1. With five axis micro milling machine, 2 D thin wall,3 D curved surface and a mini impeller is machined with precision 2. With three axis milling machine micro gears up to 20 micron thin wall, and a microelectrode machined with accuracy and precision. 3. With the hybrid five face milling machine in one set up have precisely made a work piece with flat surfaces and free from surfaces with cavity contour milling and variable contour milling operations. 2.2 Material Selections In Structural Design of Mini Milling Machine By S.B. Chandgude,S.S.Patil This research paper explains various methods to select material for different parts of mini milling machine. As per this research paper bed is made from cast iron (Grade 35 grey) and steel grade 1080 is better material for structure of spindle column making in mini milling machine which fulfil all the requirements of design and as per analysis of this research paper this analysis will get a hybrid design option for structure with a greater flexibility.

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2.3 Design and Analysis of Table For Micro Milling By R.R.Honkalas, P.M.Pawar, B.P.Ronge This research paper explains performance parameters affecting for the table i.e. direction of motion of sliding, shapes of guides, materials, frictional behavior, lubrication system, construction of table. 2.4 Machining Forces and Tool Deflections In Micro Milling By Ali Mamedov,S.Ehsan Layegh K.,Ismail Lazoglu This paper represents, comprehensive force and deflection models for micro milling were presented. The main focus of this paper were on prediction of cutting forces during micro end milling and estimating the deflection amount of the micro end mill occurred due to cutting force and deflection models were validated through the experiments and showed good agreement. 2.5 FE Analysis of Positioning Slides of Micro Milling Machine By Sushant Thambkar,Bhagyesh Deshmukh This paper represents finite element analysis of slides. In this research paper analysis done by analytical solution and finite element solution and finally the result obtained in both analysis compared with each other. Paper also shows the step by step procedure of finite analysis from creation of geometry to final solution.

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CHAPTER 3 MECHANICAL DESIGN 3.1 Introduction: The subject of machine design deals with the art of designing machine of structure. A machine is a combination of resistance bodies with successfully constrained relative motions which is used for transforming other forms of energy into mechanical energy or transmitting and modifying available design is to create new and better machines or structures and improving the existing ones such that it will convert and control motions either with or without transmitting power. It is the practical application of machinery to the design and construction of machine and structure. In order to design simple component satisfactorily, a sound knowledge of applied science is essential. In addition, strength and properties of materials including some metrological are of prime importance. Knowledge of theory of machine and other branch of applied mechanics is also required in order to know the velocity. Acceleration and inertia force of the various links in motion, mechanics of machinery involve the design. 3.2 Factor Considered: Mechanical design phase is very important from the point view of designer as whole success of the project depends on the correct design analysis of the problem. Many preliminary alternatives are eliminated during this phase. Designer should have adequate knowledge about physical properties of material, loads, stresses, deformation, and failure. Theories and wear analysis, he should identify the external and internal forces acting on the machine parts. These forces may be classified as: a) Dead weight forces b) Friction forces c) Inertia forces d) Centrifugal forces e) Forces generated during power transmission etc.

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which will almost satisfy the functional needs. Assumptions must always be on the safer side. Selection of factor of safety to find working or design stress is another important step in design of working dimensions of machine elements. The correction in the theoretical stress values are to be made according in the kind of loads, shape of arts& service requirements. Selection of material should be made according to the condition of loading shapes of products environment condition & desirable properties of material. Provision should be made to minimize nearly adopting proper lubricating methods. In mechanical design the components are listed down & stored on the basis of their procurement in two categories,  Design parts  Parts to be purchased For design parts a detailed design is done &designation thus obtain are compared to the next highest dimension which is ready available in market. The simplification the assembly as well as post production service work. The various tolerances on the work are specified. The processes charts are prepared & passed on to the work are specified. The parts to be purchased directly are selected from various catalogues &specification so that anybody can purchase the same from retail shop with the given specifications.

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3.3 Bill of Materials:

SR.NO.

PART CODE

PART NAME

QTY.

1.

MMM 01

Base

01

2.

MMM 02

Column

01

3.

MMM 03

Overhanging Arm

01

4.

MMM 04

Lead screw

03

5.

MMM 05

Handle

03

5.

MMM 06

Bolt

03

6.

MMM 06

Washer

03

7.

MMM 07

Guide Rod

06

8.

MMM 08

Square Tube

-

9.

MMM 09

Drill Machine

01

MATERIAL Mild Steel Mild Steel Mild Steel Phosphorus Bronze Mild Steel Mild Steel Mild Steel Mild Steel Standard Standard

Table No. 3.1 Bill of Materials 3.4 Specifications of Mini Milling Machine: Drilling Capacity

20 mm diameter

Face Mill Capacity

40 mm diameter

Speed

750 RPM

Motor Power

450 Watt

X-Travel

70 mm

Y-Travel

70 mm

Z-Travel

140 mm

Table No.3.2 Specifications of Mini Milling Machine

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3.5 Power Required for Drilling: = 2.82 × 10−6 × 𝑘 × 𝑛 × (𝐷2 − 𝑑 2 )1.5 + 7.875 ×0.02 (From PSG Design Data Book, Page No 12.1) Where, S= Feed/blade/revolution mm K= Material factor N= Rpm Z= No. of cutting edges in contact D= Larger dia. of hole (mm) d = Smaller dia. of hole (mm) h2=𝐶𝑆 × 320 ÷ 𝐷 h2= 18 × 320 ÷ 10=576 = 2.82 × 10−6 × 2.1 × 576 × 2(142 − 72 )1.5 + 7.87 × 0.02 =52.4 watt =0.0524 kW 3.6 Power Required for Face Milling: = 13.2 × 10−3 × 𝑘 × 𝑧 × 𝑣(1.55 × 0.02)𝛽 (From PSG Design Data Book, Page No 12.1) = 13.2 × 10−3 × 2.1 × 2 × 20(1.55 × 0.02)0.80 =0.039KW 3.7 Selection of Motor: Specification of motor are as follows:

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[1] Power= 450 watt [2] Speed=750 rpm

Motor torque: 𝑃 = 2 × 3.14 × 𝑁 × 𝑇/60 T= 60 × 450/2 × 3.14 × 750 T=5.72 N.m 3.8 Design of Lead Screw : Tmotor =5.72 N.m Torque at screw = 5.72 × 60/12 =28.6 N.m Therefore, (Mt) =28.6 N.m Where, 𝑇=(

𝑑𝑚 2

) tan(∅ + 𝜑)

Initially assuming dimensions of screw which we shall check under given system of force Selecting material for screws: Refer Page No. 194, Design of machine elements by V.B.Bhandari

Material

Coefficient of friction(starting)

Coefficient of friction(running)

Soft steel-bronze

0.10

0.08

Basic dimensions of square thread

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Ref. Page No. 5.69, PSG design data Nominal dia. Major

20

Major dia.

dia.(bolt)

(nut)

20

20.5

Minor dia.

pitch

Area of core

18

2

254

Design check: D= Nominal/outer diameter (mm) =20 mm Dc= Core /inner diameter (mm) = 18 mm Dm= Mean diameter =19 mm 𝑑𝑚 𝑀𝑡 = 𝑊 × ( ) tan(∅ + 𝛼) 2 Where, W=axial load φ =friction angle α=helix angle Helix angle: 𝑡𝑎𝑛 𝛼 = 𝐿/𝜋 × 𝐷𝑚 𝐴 = 𝜋𝑟 2 same as, = 6/9 × 16 α = 1.92 Friction angle: Ref. R.S Khurmi (Table 7.5) Coefficient of friction under different condition Condition

Coefficient of friction

Coefficient of friction

Starting

Running

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average quality of material & average running

0.18

condition

Coefficient of friction under different condition µ= tan φ 0.18=tan φ φ=10.2 𝑀𝑡 = 𝑊 × (19/2)tan(10.2 + 1.92) 𝑀𝑡 = 2.04 × 𝑊 𝑁. 𝑚𝑚 28.6 N.mm =2.04×W W=137.53 N.mm W=14.01 kg This is lifting capacity of screw using motor specifications. For screw, Ref (Page No.59-1.12) Tensile strength

Yield strength

600

380

(a) Direct tensile or compressive stress due to axial load: 𝐹𝑐 = 𝑊 × 4/3.14 × 𝑑𝑐 2 𝐹𝑐 = 137.53 × 4/3.14 × 192 𝐹𝑐 = 21.35𝑁/𝑚𝑚2 Screw is safe in compression

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(b) Torsional shear stress: 𝑀𝑡 = 3.14/(16 × 𝐹𝑐 × 𝑑𝑐 3 ) 28.6 × 103 = 3.14 × 𝐹𝑐 × 𝑑𝑐𝑎𝑐𝑡 × 193 /16 𝐹𝑐𝑎𝑐𝑡 = 9.17 𝑁/𝑚𝑚2 The screw is safe in torsion (c) Bearing pressure: 4

𝑃𝑏 = 𝑤 × 𝜋 × (𝑑𝑜2 − 𝑑𝑐 2 ) × 𝑛 Where, Pb= Bearing pressure N= No. of threads in contact. Limiting values of bearing pressure Ref. V.B Bhandari, Table No 6.4 Type of application Lead screw

Material

Sb(N/mm2)

Bronze

1-1.5

Rubbing speed High speed 15 m/min

4

𝑃𝑏 = 137.53 × 𝜋 × (202 − 182 ) × 𝑛 n = 67 Shear stress due to axial load 𝐹𝑠𝑎𝑐𝑡 = 𝑤/𝜋 × 𝑛 × 𝑑𝑐 × 𝑡 t= Thread width=P/2 t=1mm

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𝐹𝑠𝑎𝑐𝑡 = 137.53/𝜋 × 67 × 19 × 1 𝐹𝑠𝑎𝑐𝑡 = 1.51 N/mm2 Screw threads are safe in shear

Stresses due to buckling of screw: According to Rankine formula, 𝐴

𝑊𝑐𝑟 = 𝑓𝑐 × 1 + 𝑎 (𝐿𝑒/𝑘)2 Where, Wcr = Crippling loud on screw A= Area of c/s of root A= Contact Le= Equivalent unsupported length of screw decided by end condition K= Radius of gyration=dc/4 mm fc= Yield stress in compression

Ref. PSG design data Page No. 6.8 𝜋 1 4(192 ) 𝑊𝑐𝑟 = 300 × +( ) (127.6/194.2) 1 7500 𝑊𝑐𝑟 = 77.60 × 103 𝑁 As the critical load is high as compared to actual compressive load of 137.53 N the screw is safe in buckling.

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3.9 Selection of Material : The proper selection of material for the different part of a machine is the main objective in the fabrication of machine. For a design engineer it is must that he be familiar with the effect, which the manufacturing process and heat treatment have on the properties of materials. The Choice of material for engineering purposes depends upon the following factors: 1. Availability of the materials. 2. Suitability of materials for the working condition in service. 3. The cost of materials. 4. Physical and chemical properties of material. 5. Mechanical properties of material. The mechanical properties of the metals are those, which are associated with the ability of the material to resist mechanical forces and load. We shall now discuss these properties as follows: 1. Strength: It is the ability of a material to resist the externally applied forces. 2. Stress: Without breaking or yielding. The internal resistance offered by apart to an externally applied force is called stress. 3. Stiffness: It is the ability of material to resist deformation under stresses. The modules of elasticity of the measure of stiffness. 4. Elasticity:

It is the property of a material to regain its original shape

after deformation when the external forces are removed. This property is desirable for material used in tools and machines. It may be noted that steel is more elastic than rubber. 5 Plasticity: It is the property of a material, which retain the deformation produced under load permanently. This property of material is necessary for forging, in stamping images on coins and in ornamental work.

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6. Ductility: It is the property of a material enabling it to be drawn into wire with the application of a tensile force. A ductile material must be both strong and plastic. The ductility is usually measured by the terms, percentage elongation and percent reduction in area. The ductile materials commonly used in engineering practice are mild steel, copper, aluminium, nickel, zinc, tin and lead. 7. Brittleness: It is the property of material opposite to ductile. It is the property of breaking of a material with little permanent distortion. Brittle materials when subjected to tensile loads snap off without giving any sensible elongation. Cast iron is a brittle material. 8.Malleability: It is a special case of ductility, which permits material to Be rolled or hammered into thin sheets, a malleable material should be plastic but it is not essential to be so strong. The malleable materials commonly used in engineering practice are lead, soft steel, wrought iron, copper and aluminium. 9. Toughness: It is the property of a material to resist the fracture due to high impact loads like hammer blows. The toughness of the material decreases when it is heated. It is measured by the amount of absorbed after being stressed up to the point of fracture. This property is desirable in parts subjected to shock an impact loads. 10. Resilience: It is the property of a material to absorb energy and to resist rock and impact loads. It is measured by amount of energy absorbed per unit volume with in elastic limit. This property is essential for spring material. 11. Creep: When a part is subjected to a constant stress at high temperature for long period of time, it will undergo a slow and permanent deformation called creep. This property is considered in designing internal combustion engines, boilers and turbines. 12. Hardness: It is a very important property of the metals and has a wide verity of meanings. It embraces many different properties such as resistance to wear scratching, deformation and mach inability etc. It also means the ability of the metal to cut another metal. The hardness is usually expressed in numbers, which are dependent on the method of making the test. The hardness of a metal may be determined by the following test a) Brinell hardness test

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b) Rockwell hardness test c) Vickers hardness (also called diamond pyramid) test The science of the metal is a specialized and although it over flows in to real ms of knowledge it tends to shut away from the general reader. The knowledge of materials and their properties is of great significance for a design engineer. The machine elements should be made of such a material which has properties suitable for the conditions of operations. In addition to this a design engineer must be familiar with the manufacturing processes and the heat treatment shave on the properties of the materials. In designing the various part of the machine it is necessary to know how the material will function in service. For this certain characteristics or mechanical properties mostly used in mechanical engineering practice are commonly determined from standard tensile tests. In engineering practice, the machine parts are subjected to various forces, which may be due to either one or more of the following. 1. Energy transmitted 2. Weight of machine 3. Frictional resistance 4. Inertia of reciprocating parts 5. Change of temperature 6. Lack of balance of moving parts The selection of the materials depends upon the various types of stresses that are set up during operation. The material selected should with stand it. Another criteria for selection of metal depend upon the type of load because a machine part resist load more easily than a live load and live load more easily than a shock load. Selection of the material depends upon factor of safety, which in turn depends upon the following factors.

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1. Reliabilities of properties 2. Reliability of applied load 3. The certainty as to exact mode of failure 4. The extent of simplifying assumptions 5. The extent of localized 6. The extent of initial stresses set up during manufacturing 7. The extent loss of life if failure occurs 8. The extent of loss of property if failure occurs Materials selected in machine, For Base, column, overhanging arm and bolt material used : Mild steel Reasons: 1. Mild steel is readily available in market 2. It is economical to use 3. It is available in standard sizes 4. It has good mechanical properties i.e. it is easily machinable 5. It has moderate factor of safety, because factor of safety results in unnecessary wastage of material and heavy selection. Low factor of safety results in unnecessary risk of failure 6. It has high tensile strength 7. Low co-efficient of thermal expansion Properties of Mild Steel: 1. Mild steel has a carbon content from 0 .15 % to 0.30%. They are easily wieldable thus can be hardened only. They are similar to wrought iron in properties.

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2. Both ultimate tensile and compressive strength of these steel increases with increasing carbon content. They can be easily gas welded or electric or arc welded. With increase in the carbon percentage weld ability decreases Mild steel serve the purpose and was hence was selected because of the above purpose.

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CHAPTER 4 MANUFACTURING 4.1. Parameters In system design we mainly concentrated on the following parameters:4.1.1 System Selection Based on Physical Constraints:While selecting any machine it must be checked whether it is going to be used in a large scale industry or a small scale industry. In our case it is to be used by a small scale industry .So space is a major constrain. The system is to be very compact so that it can be adjusted to corner of a room. The mechanical design has direct norms with the system design. Hence the foremost job is to control the physical parameters, so that the distinctions obtained after mechanical design can be well fitted into that. 4.1.2 Arrangement of Various Components:Keeping into view the space restrictions the components should be laid such that their easy removal or servicing is possible. More over every component should be easily seen none should be hidden. Every possible space is utilized in component arrangements. 4.1.3 Components of System:As already stated the system should be compact enough so that it can be accommodated at a corner of room. All the moving parts should be well closed and compact .A compact system design gives a high weighted structure which is desired. 4.1.4 Man Machine Interaction:The friendliness of a machine with the operator that is operating in an important criteria of design. Following some of the topics included in this section. 

Design of handle



Energy expenditure in hand operation

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4.1.5 Chances of Failure:losses incurred by owner in case of any failure are important criteria of design. Factor of safety while doing mechanical design is kept high so that there are less chances of failures. Moreover periodic maintenance is required to keep unit healthy. 4.1.6 Servicing Facility:The layout of components should be such that easy servicing is possible. Especially those components which require frequents servicing can be easily disassembled. 4.1.7 Scope of Future Improvement:Arrangement should be provided to expand the scope of work in future. Such as to convert the machine motor operated; the system can be easily configured to required one. 4.1.8 Height of Machine from Ground:For ease and comfort of operator the height of machine should be properly decided so that he may not get tired during operation. The machine should be slightly higher than the ground level, also enough clearance should be provided from the ground for cleaning purpose. 4.2 Parts of Mini Milling Machine: 4.2.1. Base:Base of the machine serves as a foundation member for all other parts of the machine which rest upon it. It carries the column at its one end. In some machines, the base is hollow and serve as a reservoir for cutting fluid. The recommended material for base is mild steel which is mostly used in manufacturing of base of various mini milling machine. A hollow rectangular cross-section of mild steel with dimension 2.5 mm and length 800 mm is selected.

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The following is the list of operation performed to produce the base with a brief description of each operation arranged sequentially: 1. Cutting: In this operation main target is to cut the available rectangular bar as per required dimension. We cut the four rectangular bar of 150 mm length and two bars of 250 mm length and two more bars of 200 mm length. These eight bars are used to obtain base structure. 2. Surface cleaning: This process is done to make the bar burr free which are produced due to cutting operation. End of each rectangular bar up to particular length is also cleaned to obtain proper welding joint between two bars. 3. Welding: In this process all the rectangular bars are joined as per required orientation to obtain the final structure of base. 4. Fig. 4.1gives constructional details about the frame.

Fig No.4.1 Base of Mini Milling Machine 4.2.2. Column:The column is the main supporting frame mounted vertically on the base. The front vertical face of the column is accurately machined and is provided with guide ways for supporting the overhanging arm .The top of the column is finished to hold an over arm that extends outward at the front of the machine. column is made of same material as that of frame, Mild steel with solid circular stock of outer diameter 25 mm and length 1200 mm. The following are the list of operation performed to produce the column, arranged sequentially:

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1. Cutting: This process is done to cut the starting stock piece into two part of length 600 mm. 2. Facing: This operation is done on lathe machine to make the surface flat of both pieces which are cut in previous step. In this process length of each piece is reduce to give smooth finish to both sides. 3. External turning process: This process is done to reduce the outer diameter of the starting stock piece from 25 mm to 24 mm. 4. Welding: In this process rectangular bars are joined to the base as per required orientation to obtain the final structure of column. Fig. 4.2 gives constructional details about the column.

Fig.No.4.2 Column of Mini Milling Machine 4.2.3. Overhanging arm:The overhanging arm that is mounted on the top of the column extends beyond the column face and serves as a bearing support for the drilling machine. The arm is adjustable to hold different sizes of machine. Take hollow circular rod of internal diameter 18 mm and external diameter 22 mm with length of 200 mm & also take square tube of 2.5 with length 82 mm.

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The following are the list of operation performed to produce the overhanging arm, arranged sequentially: 5. Cutting: This process is done to cut hollow circular rod into two part of length 100 mm. and also cut the square tube in two pieces of length 40 mm 6. Facing: This operation is done on lathe machine to make the surface flat of both pieces which are cut in previous step. In this process length of each piece is reduce to give smooth finish to both sides. 7. External turning process: This process is done to reduce the outer diameter of the starting stock piece from 22 mm to 21 mm. 8. Welding: In this process rectangular bars are joined to the base as per required orientation to obtain the final structure of overhanging arm. Fig. 4.3 gives constructional details about the overhanging arm.

Fig No.4.3 Overhanging Arm 4.2.4 Lead screw:The function of lead screw is to transmit the power. At the end of lead screw handle is attached. By revolving handle motion is transmitted to the table, three lead screws used for moment of three different axis. Take circular rod diameter 14 mm with length of 250 mm. The following are the list of operation performed to produce the lead screw, arranged sequentially:

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9. Facing: This operation is done on lathe machine to make the surface flat of both pieces which are cut in previous step. In this process length of each piece is reduce to give smooth finish to both sides. In this step length is reduced to 240 mm. 10. External turning process: This process is done to reduce the outer diameter of the starting stock piece from 14 mm to 13 mm. 11. Threading: Threading is done on lathe machine thread is produced over the length of rod. Fig. 4.4 gives constructional details about the lead screw.

Fig.No.4.4 Lead screw with X axis 4.2.5 Axies:The mini milling machine is provided with three axis namely X,Y and Z. The purpose of axis is to provide longitudinal, cross and vertical motions of the table. A hollow rectangular cross-section of mild steel with dimension 2.5 mm with length 300 is selected and take circular rod of diameter 12 mm with length 600 mm and hollow circular tube of internal diameter 12 mm and external diameter 18 mm. The following is the list of operation performed to produce the base with a brief description of each operation arranged sequentially:

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5. Cutting: In this operation main target is to cut the available rectangular bar as per required dimension. We cut the two rectangular bar of 300 mm length and two bars of 150 mm length. These four bars are used to obtain base structure. Cut the circular rod into two pieces. Cut hollow circular rod into two pieces of length 100 mm 2. Facing: This operation is done on lathe machine to make the surface flat of both pieces which are cut in previous step. In this process length of each piece is reduce to give smooth finish to both sides. 3. External turning process: This process is done to reduce the outer diameter of the starting stock. 4. Welding: In this process all the rectangular bars, circular rod and hollow (guide rod) are joined as per required orientation to obtain the final structure of Z axis. Fig.4.5 gives constructional details about the Z axis assembly.

Fig 4.5 X & Y Assembly 4.2.6 Handle :Handle is welded at the end of lead screw, handle is rotated by hand and motion is transmitted to the table through lead screw.

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Take circular rod diameter 13 mm with length of 200 mm. The following are the list of operation performed to produce the handle, arranged sequentially: 1. Cutting: In this process rod of circular diameter 13 mm cut into 3 pieces of length 62 mm. 2. Facing: This operation is done on lathe machine to make the surface flat of both pieces which are cut in previous step. In this process length of each piece is reduce to give smooth finish to both sides. In this step length is reduced to 60 mm. 3. External turning process: This process is done to reduce the outer diameter of the starting stock piece from 13 mm to 12 mm. Fig. 4.6 gives constructional details about the lead screw.

Fig.No.4.6 Handle 4.2.7 Vice:Vices are the most common appliances for holding work on milling machine table due to its quick loading and unloading arrangement. There are mainly three types of vices commonly used in milling machines. They are plain vice, swivel vice, and tool makers universal vice. The plain vice bolted directly on the milling machine table is the most common type of machine vice used for plain milling operations. The vice may be fastened to the table with the jaws set either parallel or at right angles to the table T- slots. Work is

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clamped between the fixed and movable jaw and for holding work pieces of irregular shape special jaws sometimes used.

Fig.No.4.7 Vice of Mini Milling Machine 4.3 Constructional Diagram of Mini Milling Machine:

Fig.No.4.8 Constructional Diagram of Mini Milling Machine

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4.4 Process Sheet: The various tolerances on work piece are specified in the manufacturing drawing. .The process chart are prepared and passed on to the manufacturing stage. The parts are to be purchased directly are specified and selected from standard catalogues 4.4.1 Process Sheet of Base: PART CODE: MMM 01 PART NAME : Base Sr . N o.

Descripti on of Operatio n

01 Take . square tube of 2.5*2.5m m& clamp 02 Cut 4 . pieces of 150 mm length 03 Cut 2 . pieces of 250 mm length 04 Cut 2 . pieces of 200 mm length 05 Welding . these pieces as per the drawing

MATERIAL SPECIFICATIONS : Mild Steel RAW MATERIAL SIZE : □ Tube 2.5*2.5 QUANTITY : 1Nos

Jigs & Machi Fixtur ne e Tools

Tools Cuttin Measuri g Tools ng Instrum ent _ _

Vice

_

Vice

_

Hacksa w blade

Vice

_

Vice

Vice

Time in Minutes Settin Machi Total g ne Time Time Time 2

_

2

Scale

5

10

15

Hacksa w blade

Scale

5

15

20

_

Hacksa w blade

Scale

5

15

20

Weldin g machin e

Weldin g rod

5

20

25

_

Table No.4.1 Process Sheet of Base

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4.4.2 Process Sheet of Handle:

PART CODE: MMM 05 PART NAME : Handle S r . N o .

1

2

3

MATERIAL SPECIFICATIONS : Mild Steel RAW MATERIAL SIZE : Ø22 *400 QUANTITY : 3 Nos Tools

Description of Operation

Take circular rod of Ø 22 and cut into 3 pieces of length 125 mm Turn Ø 22 to Ø 20 of all 3 pieces Facing B/S of all 3 pieces

Jigs & Fixtur Machi Cutting ne e Tools Tools

Vice

Three jaw chuck Three jaw chuck

Time in Minutes Measurin g Instrume nt

_

Hacksa w Blade

Vernier

Lathe

Turning Tool

Vernier

Lathe

Facing Tool

Vernier

Setti ng Tim e

Machi ne Time

Total Time

5

15

20

5

15

20

5

10

15

Table No.4.2 Process Sheet of Handle

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4.4.3 Process Sheet of Guide Rod: PART CODE: MMM 07 PART NAME : Guide rod S r . N o .

MATERIAL SPECIFICATIONS : Mild Steel RAW MATERIAL SIZE :ID Ø 26 *400 QUANTITY : 6 Nos Tools

Descriptio n of Operation

1

Take circular rod of ID Ø 26 and cut into 6 pieces of length 50 mm

2

Turn outer diameter

3

Facing B/S of all 6 pieces

Time in Minutes

Measur Jigs & Machin Cutting ing Fixture e Tools Tools Instru ment

Vice

Three jaw chuck Three jaw chuck

_

Hacksa w Blade

Lathe

Turning Tool

Vernier

Lathe

Facing Tool

Vernier

Vernier

Settin g Time

Machin e Time

Tota l Tim e

5

15

20

5

10

15

5

10

15

Table No.4.3 Process Sheet of Guide Rod

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4.4.4 Process Sheet of Overhanging Arm:

PART CODE: MMM 03 MATERIAL SPECIFICATIONS : Mild Steel PART NAME : Overhanging arm RAW MATERIAL SIZE : QUANTITY : 1 Nos Tools Sr. No.

01.

02.

03.

04.

05.

06.

Descriptio n of Operation Take hollow circular tube of internal Ø26 & facing B/S Cut 2 pieces of lengths 170 mm Cut 2 pieces of square tube having length 140mm Welding of square tubes & hollow circular tube as per drawing Take sheet metal of 2 mm thick, bend in circular form Weld circular sheet metal piece between 2 square

Jigs & Machi Cutting Fixture ne Tools Tools

Measuri ng Instrum ent

Three jaw chuck

Lathe

_

Vise

_

Hacksa w blade

Scale

Vise

_

Hacksa w blade

Scale

Vise

Weldi ng machi ne

_

_

Bendi ng machi ne

_

Vise

Weldi ng Machi ne

_

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Vernier

Scale

Vernier

_

Time in Minutes Setti Machi ng Total ne Tim Time Time e

5

10

15

5

10

15

5

15

20

5

15

20

5

15

20

5

15

20

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tubes

Table No.4.4 Process Sheet of Overhanging Arm

4.4.5 Process sheet of Lead Screw:

PART CODE : MMM 04 PART NAME : Lead Screw

MATERIAL SPECIFICATIONS : Mild Steel RAW MATERIAL SIZE : Ø14 *250 QUANTITY : 3 Nos Tools

Sr. No.

01.

02.

03.

04.

05.

Descriptio n of Operation Clamp stock Facing both side total length 250 mm Turn OD Ø 14 to OD Ø 13 Turn OD Ø 13 to OD Ø 12 Threading 0.5 mm pitch

Measur Jigs & Machi Cutting ing Fixture ne Tools Instru Tools ment Three jaw Lathe _ _ chuck Three jaw chuck Three jaw chuck Three jaw chuck Three jaw chuck

Lathe

Facing Tool

Vernier

Lathe

Turning Tool

Vernier

Lathe

Turning Tool

Venier

Lathe

Threadi ng Tool

Vernier

Time in Minutes Tota Settin Machin l g e Time Tim Time e 10

_

10

5

12

17

_

12

12

_

15

15

20

40

60

Table No.4.5 Process Sheet of Lead Screw

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CHAPTER 5 EXPERIMENTAL PROCEDURE 5.1 Experimental Procedure for Drilling on Mini Milling Machine: 1. Clamp the work piece properly on the vice. 2. Change the drill bit of required dimension and as per the material of work piece. 3. Adjust the X,Y and Z axis properly. 4. Start drilling operation and slowly moves down Z axis as per depth requirement. 5.2 Experimental Procedure for Milling on Mini Milling Machine: 1. Clamp the work piece properly on the vice. 2. Change the cutter of required dimension and as per the material of work piece. 3. Adjust the X,Y and Z axis properly. 4. Start milling operation and slowly moves down Z axis as per depth requirement.

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CHAPTER 6 RESULT & DISCUSSION 6.1 Experimental Results: 6.1.1 Test on Nylon: 6.1.1.1 Drilling operation:

Sr.No. 01

Standard cutter

Diameter

Depth

Depth

diameter

achieved

Required

achieved

Ø10 mm

10.1 mm

50 mm

50.2 mm

Table 6.1 Nylon Drilling Operation Result Variation in diameter = 10.1-10 = 0.1 mm Variation in depth = 50.2-50 = 0.2 mm 6.1.1.1 Slot milling operation:

Sr.No. 01

Standard cutter

Slot diameter

Slot length

Slot length

diameter

achieved

Required

achieved

Ø10 mm

10.2 mm

30 mm

30.3 mm

Table 6.2 Nylon Slot Milling Result Variation in slot diameter = 10.2-10 = 0.2 mm Variation in slot length = 30.3-30 = 0.3 mm From above discussion on nylon material, variations in the dimensions are in the acceptable range.

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6.1.2 Test on Wood: 6.1.2.1 Drilling operation:

Sr.No.

Standard cutter

Diameter

Depth

Depth

diameter

achieved

Required

achieved

Ø10 mm

10.05 mm

50 mm

50.1 mm

01

Table 6.3 Wood Drilling Operation Result Variation in diameter = 10.05-10 = 0.05 mm Variation in depth = 50.1-50 = 0.1 mm 6.1.2.2 Slot milling operation:

Sr.No.

Standard cutter

Slot diameter

Slot length

Slot length

diameter

achieved

Required

achieved

Ø10 mm

10.15 mm

30 mm

30.15 mm

01

Table 6.2 Wood Slot Milling Result Variation in slot diameter = 10.1-10 = 0.1 mm Variation in slot length = 30.15-30 = 0.15 mm From above discussion on wood, variations in the dimensions are in the acceptable range. 6.2 Analysis Procedure: Numerical simulations are carried out using ANSYS and the procedure incorporated in this session 6.2.1 ANSYS Pre-Processor: 6.2.1.1 Creation of the model geometry To begin with the analysis process, the Model generation is carried out in this processor. A solid Model of the generated in CATIA is imported in ANSYS 6.2.1.2 Define material properties

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In the present work, Mild steel is used as material for design. The young’s modulus and the Poisson ratio is taken as 210 Gpa and 0.35 respectively. 6.2.1.3 Generating the mesh As the material properties for the material selected are defined for the solid model. Due care is required in meshing of a sensitive zone and comparatively insensitive zone. Sensitive zones are hence meshed using fine mesh whereas insensitive zone is meshed using relatively coarse mesh. 6.2.2. ANSYS Solution: The method model is imposed with the boundary conditions and the load steps for the detailed displacement (deformation) and stress analysis. 6.2.2.1 Define analysis type and analysis option In the current work, one of the prime objectives is to attain the micro displacements. Dynamic aspect is not considered as the scope of the study. Static structural analysis module of ANSYS is considered for the analysing the different components of mini milling machine. The static analysis focused on aspects such as force and displacement relationships. 6.2.2.2 Specify boundary conditions After selection of the analysis type, it is then required to impose boundary conditions for the analysis. In this case, the model is fixed at one side and force is applied on the top of the work piece. 6.2.2.3 Obtain Solution This step indicates the solution process of model. The solution is carried out for resulting deformation. The compiler processes the model and keeps the solution ready for further processing. 6.2.3 ANSYS General Postprocessor: One of the most important step is to view the results of an analysis in order to understand how the applied loads affects our design. General processor is used to

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review the results for static or steady state problems. Using this post processor we can see contour displays, deformed shapes, element forces and moments, nodal displacements, stress contour, von misses stresses, principal stresses etc. We can also see the simulation, which indicates variation of stress, displacement at different locations of component 6.3 Modelling & Analysis Results: 6.3.1 Modelling of Base:

Fig No 6.1 Modelling of Base CATIA→ Part modelling→ Select the plane→ Top view→ Sketch→ Rectangle→ Drawn the rectangle as per the dimensions→ Exit workbench→ Extrude (Apply thickness) Select bottom view→ Sketch on the face→ Draw the square of 2.5*2.5→ Extrude the length as per required dimension→ Rectangular pattern to create same part.

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6.3.2 Analysis of Base:

Fig No 6.2 Analysis of Base Maximum deformation occurs at the centre. Here we can see total deformation to be very less, which is very small value and hence acceptable. 6.3.3 Modelling of Column:

Fig No 6.3 Modelling of Column CATIA→ Part modelling→ Select the plane→ Top view→ Sketch→ Circle→ Drawn the circle as per the dimensions→ Exit workbench→ Extrude (Apply length)

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Design and Manufacturing of Mini Milling Machine

Select front view→ Sketch on the face→ Draw the rectangle→ Extrude the length as per required dimension 6.3.4 Analysis of column:

Fig.6.4 Analysis of Column In column, maximum deformation occurs at top portion. The maximum deformation occurred in column is 3.0038e-11 is very less and hence acceptable. 6.3.5 Modelling of Overhanging Arm:

Fig No 6.5 Modelling of Overhanging Arm

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CATIA→ Part modelling→ Select the plane→ Top view→ Sketch→ Circle→ Drawn the circle as per the dimensions→ Exit workbench→ Extrude (Apply length) Select face→ Sketch on the face→ Draw the square→ Extrude the length as per required dimension Select top view→ Sketch on the face→ Draw the circular shape (holder) → Extrude the length as per required dimension 6.3.6 Analysis of Overhanging Arm:

Fig No .6.6 Analysis of Overhanging Arm In overhanging arm deformation occurs in extended part of overhanging arm. Maximum deformation is 7.77e-8 which is very less. Hence deformation is acceptable.

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Design and Manufacturing of Mini Milling Machine

6.3.7 Modelling of Lead Screw:

Fig No 6.7 Modelling of Lead Screw CATIA→ Part modelling→ Select the plane→ Front view→ Sketch→ Circle→ Drawn the circle as per the dimensions→ Exit workbench→ Extrude (Apply length)→ Select the surface→ Apply threads 6.3.8 Analysis of Lead Screw:

Fig No 6.8 Analysis of Lead Screw In lead screw, deformation takes place at end whose connected to the handle. Maximum deformation is 2.20e-7 which is very small. Hence lead screw is safe.

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6.3.9 Modelling of Handle:

Fig No 6.9 Modelling of Handle CATIA→ Part modelling→ Select the plane→ Front view→ Sketch→ Circle→ Drawn the circle as per the dimensions→ Exit workbench→ Extrude (Apply length) 6.3.10 Analysis of Handle:

Fig No 6.10 Analysis of Handle Maximum stresses generated at middle portion of the handle, which is connected to handle. Maximum stress induced within limit, Hence the design is safe.

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CHAPTER 7 COST ESTIMATION 7.1 Cost Estimation of Raw Material: 7.1.1. For Base: Material is Mild Steel, Density of Mild Steel = 7800 Kg/m3 Volume of the stock = 𝐿 × 𝐵 × 𝐻 = 250 × 25 × 2 = 12500𝑚𝑚3 = 1250 × 10−9 𝑚3 Mass of the material = 𝜌 × 𝑣 = 7800 × 12500 × 10−9 = 0.0975𝑘𝑔 ≈ 0.10 𝑘𝑔 No. of base joints required= 8 Total mass of base = 8 × 0.10 = 0.80 𝑘𝑔 ≈ 1 𝑘𝑔 7.1.2. For Column: Material is Mild Steel, Density of Mild Steel = 7800 Kg/m3 𝜋

Volume of the stock= 4 𝑑 2 × l = 0785 × 18 × 18 × 60 = 152.68 × 103 𝑚𝑚3 = 152.68 × 10 −6 𝑚3 Mass of the material = 𝜌 × 𝑣 = 7800 × 152.68 × 10−6 = 1.16 Kg. No. of rods required

=2

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Total mass of column = 2 × 1.16 𝑘𝑔 = 2.32 𝑘𝑔 ≈ 2.50 𝑘𝑔 7.1.3 For Lead Screw: Material is Mild Steel, Density of Mild Steel= 7800 Kg/m3 𝜋

Volume of the stock = 4 𝑑 2 × l 𝜋

= 4 102 × 260 = 20420.35 mm3 = 20420.35 × 10−9 𝑚3 Mass of the material = 𝜌 × 𝑣 = 7800 × 20420.35 × 10−9 𝑚3 = 0.16 Kg. No. of lead screw = 3 Total mass of lead screw = 3 × 0.16 = 0.48 𝑘𝑔 ≈ 0.50 𝑘𝑔 7.1.4. For Supporting Rod: Material is Mild Steel, Density of Mild Steel= 7800 Kg/m3 𝜋

Volume of the stock = 4 𝑑 2 × l 𝜋

= 4 122 × 300 = 33929.20.35 mm3

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= 33929.20×10-9 m3 Mass of the material = 𝜌 × 𝑣 = 7800 × 33929.20 × 10−9 = 0.26 Kg. No. of supporting rod = 4 Total mass of coupling

= 4 × 0.26 = 1.04 Kg.

7.1.5 For Guide Rod: Material is Mild Steel, Density of Mild Steel= 7800 Kg/m3 𝜋

Volume of the stock= 4 (24 × 24 − 18 × 18) × 300 = 33646.45 mm3 = 33646.45 × 10−9 m3 Mass of the material = 𝜌 × 𝑣 = 7800 × 33646.45 × 10−9 = 0.26 Kg. No. of guide rod = 6 Total mass of guide rod = 6 × 0.26 = 1.6 Kg. Thus the summary of above calculation is depicted in tabular form given below:

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Design and Manufacturing of Mini Milling Machine

Material

Mass (Kg.)

Cost/Kg.

Total Cost

Mild steel for base

1

80

80

2.50

80

200

0.50

80

40

1.6

80

128

1.04

80

84

1.8

80

144

Mild steel for column Mild steel for lead screw Mild steel for supporting rod Mild steel for guide rod Mild steel for supporting frame

Total Raw Material Cost (Rs.)

676

Table 7.1 Raw Material Cost 7.2 Standard Component Cost: Cost/Unit

Sr.No.

Component

Qty.

1

Vice

1

470

470

2

Drill Machine

1

1500

1500

3

Bolts

6

3

18

4

Washer

3

2

6

Qty

Total Cost

Total Cost (Rs.)

1994

Table 7.2 Standard Component Cost

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7.3 Accessories Cost: Cost/Unit

Total

Qty

Cost

1

100

100

2

120

240

Total

340

Sr.No.

Accessory

Qty.

1

Drill bit

2

Mill cutter

Table 7.3: Accessories Cost 7.4 Machining Cost:

Sr. No.

Operation

Rate/Hr.(Rs)

Hours

Total Cost (Rs.)

1

Cutting

------

----

150

2

Facing

120

3

360

3

Turning

120

5

600

4

Threading

140

6

840

6

Grinding

-----

-----

100

7

Welding

----

-----

500

Total Machining Cost (Rs.)

2610

Table 7.4 Standard Machining Cost

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Design and Manufacturing of Mini Milling Machine

7.5 Total Cost: Element

Cost (Rs.)

Raw Material Cost

676

Standard Component Cost

1994

Accessories Cost

340

Machining Cost

2610

Miscellaneous Cost

1080

Total

6700

Table 7.5 Overall Cost

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CHAPTER 8 CONCLUSION AND FUTURE SCOPE 8.1 Conclusion: With the increasing demand for small scale high precision parts in various industries, the market for small scale machine tools has grown substantially. Using small machine tools to fabricate small scale parts can provide both flexibility and effiency in manufacturing approaches and reduce the capital cost, which is beneficial for small business owners. In this project, a small scale three axis mini milling machine is designed and analysed under very limited budget of RS 10,000. 8.2 Future Scope: We can make it computerised, moment of axis can be controlled by using motors. We have to make graduations on the each axis. With the help of these graduations and the sensors, we can find the co-ordinates on X,Y and Z axis. With the help of these co-ordinates, we can move the spindle accordingly and the operations performed at required location. As this system can be made computerised, perfect accuracy will be achieved.

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CHAPTER 9 REFERANCES Reference books: V.B.Bhandari, Design of Machine Elements-3rd edition, Mc Graw Hill Education R.S.Khrmi, Machine Design-5th edition, S-Chand Publication Research papers: Manish Modi , Krishna Dave. ,The review of usability in portable milling machine from micro to macro parts ,IJIRST –International Journal for Innovative Research in Science & Technology| Volume 1 | Issue 6 | November 2014 S.B.Chandgude , S.S.Patil, Material selection in structural design of mini milling machine, International Journal of Research in Advent Technology, Volume 2,Issue 1,Janurary 2014 R.R.Honkalas, P.M.Pawar, B.P.Ronge, Design and analysis of table for micro milling ,International Journal of Engineering Research and Applications, Volume 2,Issue 6, December 2012 Ali Mamedov ,S.Ehsan Layegh K., Machining forces and tool deflections in micro milling,14th CIRP Conference on Modelling of Machining Operations. Sushant Thambkar,Bhagyesh Deshmukh,FE Analysis of positiong slides of micro milling machine, International Journal of Emerging Technology and Advanced Engineering ,Volume 3,Issue10,Octomber 2013 Handbooks: PSG Design Data Book, Faculty of Mechanical Engineering, PSG College of Technology, Coimbatore N.K.Mehta,Machine Tool Design, Tata McGraw-Hill Education 2012

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APPENDIX Drawing of Machine Parts

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