Report Jig and Fixture (Surface Grinding )

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JIGS AND FIXTURES ASSIGNMENT 1 3BMFP Introduction In this project, product that had been chosen is brake disc. To manufacture break disc, there are several process of machining that need to be done but only one machining process will be choose. The critical part processing of brake disc is the surface finishing and to done this process, grinding fixture is required to get the excellent thickness and accuracy of the surface finishing. This surface finishing of break disc is important for the efficiency of the break disc to functioning. Braking system in all vehicles must be works in good condition to make sure the safety of passenger. All things that had been decided of the product, part, process, material and others must be justify and have a reasonable reason. A brief concept taking from researching about some of the jigs and fixtures that already exists today and a new design of jig and fixture for the part product processing has been made where it is able to increase accuracy and precision of the machining and also reduce the load and unload process time. Objective The objective of this assignment is to familiarize the student with process selection issues related to the design of jig and fixture. Students also need to identify material of the product 1

Transcript of Report Jig and Fixture (Surface Grinding )

JIGS AND FIXTURES ASSIGNMENT 1

JIGS AND FIXTURES ASSIGNMENT 13BMFP

IntroductionIn this project, product that had been chosen is brake disc. To manufacture break disc, there are several process of machining that need to be done but only one machining process will be choose. The critical part processing of brake disc is the surface finishing and to done this process, grinding fixture is required to get the excellent thickness and accuracy of the surface finishing. This surface finishing of break disc is important for the efficiency of the break disc to functioning. Braking system in all vehicles must be works in good condition to make sure the safety of passenger. All things that had been decided of the product, part, process, material and others must be justify and have a reasonable reason. A brief concept taking from researching about some of the jigs and fixtures that already exists today and a new design of jig and fixture for the part product processing has been made where it is able to increase accuracy and precision of the machining and also reduce the load and unload process time.

Objective The objective of this assignment is to familiarize the student with process selection issues related to the design of jig and fixture. Students also need to identify material of the product and collect all the detail information about the manufacturing process from raw material until the part becomes a product. Moreover, all the design consideration of jigs and fixtures must be state and illustrate the method of locating, supporting, clamping and guidance of cutting tool in jigs and fixture to simplify the machining process. Student also need to justify the crucial of the process related with it actual performance and cost.

Problem statementIn order to get excellent surface finishing of break disc, there will be some problems in mass production to get continuous accuracy and same thickness of the surface. Higher repeatability will cause a higher cost needed and will not get a good quality every single of break disc that have been produce. This report is to encounter the problem face by industry by propose a fixture to hold, locate and support the break disc during machining process. Student is required to identify the processes that are used in selected part. Student also required having evidence and knowing the process characteristic and then student are able to think on their jigs and fixtures that match the selected part.Jigs and fixture are production work holding devices used to manufacture duplicate parts accurately. The correct alignment between the cutter or other tool, and the workpiece must be maintained. In many cases, it is difficult to design the locating, supporting and clamping for surface grinding. To do this a jig and fixture is designed and built to hold, support and locate the part to ensure that the part machined within the specified limits and accurate.

Part type and purposeAll type of vehicle must have braking system to complete the working system complete. This report is going to discuss further on braking system of motorcycle. Disc brakes were invented in 1902 and patented by Birmingham car maker Frederick William Lanchester. His original design had two discs which pressed against each other to generate friction and slow his car down. It wasn't until 1949 that disc brakes appeared on a production car though. Basically, braking system is disc brake system consists of a brake disc, a brake caliper and brake pads. A disc brake is a type of brake that uses calipers to squeeze pairs of pads against a disc in order to create friction that retards the rotation of a shaft, such as a vehicle axle, either to reduce its rotational speed or to hold it stationary. The energy of motion is converted into waste heat which must be dispersed. Disc brakes are most commonly used for vehicle braking but they are applicable to almost any rotating shaft. The different between car and motorcycle brake disc is the surface which is car brake disc have no drilled hole on the surface while motorcycle have the drilled hole. Despite it has different figure but the mechanism of the braking system is just same which doesnt have any much different.

Picture 1: Basic brake disc motorcycle Picture 2: Basic brake disc car

Before start to decide which part processing that need to choose, some research had been done in order to find which part is the most critical part in order for the brake disc to be functioning. There are several parts that had been discussed that are the hole, surface and side of the brake disc. The side of the brake disc is not the critical part as it doesnt affect the braking system. Then the drilled hole is one of the critical parts as it functions for the air to pass across and cool down the brakes. Despite it critical part, but it doesnt seem like it had been drilling because it will not productive if every hole had been drilling because it mass production product. In order to known whether the hole is drilled or only stamping process, cross section of the break disc had been taken by cut the break disc using laser cutting machine. After that, the cross sections of the break disc are looked under the microscope to get the structure whether it is circular or linear.

Picture 3: Laser cutting processAfter done the laser cutting machine, the cross section is check under microscope and the results show that the break disc had been done stamping process not a drilling process. There are seen have drawn phenomenon that prove it was undergo the stamping process. This phenomenon basically occurs in industrial sheet metal stamping processes. In the process, a strip with the fixed width is drawn by the elliptical tool and laid freely. Therefore, the primary springback along the longitudinal direction and the secondary springback along the transverse direction of the strip occur at the same time.

Picture 4: Cross-section of break disc

Picture 5: Structure of the break disc under microscope

After done the process, it shows that the drilled hole is not a machining part. Lastly, surface finishing had been chosen as the crucial part of the machining break disc. Surface finishing of the break disc is important for the efficiency of the breaking system. The minimum thickness specification is an important dimension because it is the minimum thickness that provides safe braking. As a rotor wears and becomes thinner, it has less mass. This reduces the rotors ability to absorb and dissipate heat. It also reduces the strength of the rotor, increasing the risk of cracking or even breaking (rotor failure).Thats why the thickness of the rotors should always be measured every time the brakes are serviced. If a rotor is worn down to the minimum thickness specification, or cannot be resurfaced without exceeding the dimension, it must be replaced. So that surface grinding of the brake disc is really the most crucial part.In some cases, rotors may not have to be resurfaced when the pads are replaced. If they are relatively smooth with minimal grooving, they may not need to be cut. However, most professional brake technicians wont take a chance on not resurfacing the rotors for fear the brakes may be noisy or not feel right until the pads are fully seated in. Resurfacing restores a flat, smooth surface that provides the proper friction characteristics, minimizes noise-producing vibrations and allows for maximum pad contact.Installing new pads on a grooved rotor causes the pads to ride on the high spots of the rotor. Eventually, the pads will wear down and make full contact with the rotors as they seat in. But this increases pad wear and decreases overall pad life. So it could also be argued that not resurfacing the rotors is counterproductive to maximizing brake life.The surface finish on the rotors also is important because it affects the friction characteristics of the brakes, pad seating, break-in, wear and noise. Most new OEM rotors today have a surface finish between 30 and 60 inches RA (roughness average), with many falling in the 40 to 50 RA range. Some OEM specifications say that anything less than 80 RA is acceptable. If rotors are resurfaced, they should be cut to meet these specifications using sharp lathe bits and proper rotation and feed speeds.

Brake rotor technologyIf a brake rotor was a single cast chunk of steel, it would have terrible heat dissipation properties and leave nowhere for the vaporised gas to go. Because of this, brake rotors are typically modified with all manner of extra design features to help them cool down as quickly as possible as well as dissipate any gas from between the pads and rotors. The diagram here shows some examples of rotor types with the various modifications that can be done to them to help them create more friction, disperse more heat more quickly, and ventilate gas.Different styles of disc brake rotor1: Basic brake rotor. 2: Grooved rotor - the grooves give more bite and thus more friction as they pass between the brake pads they also allow gas to vent from between the pads and the rotor. 3: Grooved, drilled rotor - the drilled holes again give more bite, but also allow air currents (eddies) to blow through the brake disc to assist cooling and ventilating gas. 4: Dual ventilated rotors - same as before but now with two rotors instead of one, and with vanes in between them to generate a vortex which will cool the rotors even further whilst trying to actually 'suck' any gas away from the pads.

Material break discHardened steel is a type of carbon steel used for making tools and heavy machine parts. This material consists of steel that has been specially treated to improve its hardness and strength. Compared to standard steel, the hardened type offers greater wear resistance and durability, making it well-suited to heavy-duty applications. Basically, many parts of motorcycle including the break disc are used hardened steel material.To make hardened steel, manufacturers heat carbon steel to high temperatures, then subject it to a process called quenching. During quenching, the steel is rapidly cooled in a solution of brine or water. After quenching, the steel is very hard, yet also extremely brittle. To reduce brittleness while maintaining the added hardness of the steel, manufacturers then temper the metal by reheating it once again and letting it cool naturally. By combining quenching and tempering, steel makers can create products that are harder than standard carbon steel, yet durable enough to withstand cracking or damage caused by sharp impacts.The term hardened steel may also refer to metal that has been case hardened. This type of metal goes through a slightly different quenching and tempering process, which gives it a tough and wear-resistant exterior while eliminating all brittleness within the core of the steel. Cased steel is used to make objects like handguns, where exterior wear resistance must be coupled with maximum strength throughout the material.One of the primary advantages to hardened steel is its added resistance against wear and abrasion. This material can withstand frequent abuse and heavy loads without damage or failure. It is also better able to resist rust and corrosion than standard steel products.Despite its many advantages, hardened steel may not be appropriate for all types of applications. Compared to standard carbon steel, this material is fairly brittle, even after going through the tempering process. This means it is unable to withstand damage from sharp impacts. Quenching and tempering also lowers the melting point of steel, which could pose problems in terms of fire safety. This could also prevent hardened steel from being used in some projects where it will be subject to high temperatures, such as near engines or other large machines.Braking system worksAs mention earlier, braking system of car basically has same mechanism as the motorcycle. Here is the location of the disc brakes:

The main components of a disc brake are:The brake padsThe caliper, which contains a pistonThe rotor, which is mounted to the hub

Motorcycle brakes have a caliper, which squeezes the brake pads against the wheel. In a disc brake, the brake pads squeeze the rotor instead of the wheel, and the force is transmitted hydraulically instead of through a cable. Friction between the pads and the disc slows the disc down. A moving motorcycle has a certain amount of kinetic energy, and the brakes have to remove this energy from the motorcycle in order to stop it. Each time it stops, the brakes convert the kinetic energy to heat generated by the friction between the pads and the disc.

Self-Adjusting BrakesThe single-piston floating-caliper disc brake is self-centering and self-adjusting. The caliper is able to slide from side to side so it will move to the center each time the brakes are applied. Also, since there is no spring to pull the pads away from the disc, the pads always stay in light contact with the rotor (the rubber piston seal and any wobble in the rotor may actually pull the pads a small distance away from the rotor). This is important because the pistons in the brakes are much larger in diameter than the ones in the master cylinder. If the brake pistons retracted into their cylinders, it might take several applications of the brake pedal to pump enough fluid into the brake cylinder to engage the brake pads.

Brake actuatorsBrakes are all well and good, but you need some method of applying them in order for them to work. The method by which the force from your hand or foot reaches the brake itself is all to do with the brake actuator system. Mostly type of brake actuators used is a single-circuit hydraulic. It is the type of brake system used on most cars and motorbikes today. Gone are the cables and bars, replaced instead with a system of plungers, reservoirs and hydraulic fluid. Single-circuit hydraulic systems have three basic components - the master cylinder, the slave cylinder and the reservoir. They're joined together with hydraulic hose and filled with a non-compressible hydraulic fluid (see brake fluid below). When you press your foot on the brake, or squeeze the brake lever, you compress a small piston assembly in the master cylinder. Because the brake fluid does not compress, that pressure is instantaneously transferred through the hydraulic brake line to the slave cylinder where it acts on another piston assembly, pushing it out. That slave assembly is either connected to a lever to activate the brakes, or more commonly, is the brake caliper itself, with the slave cylinder being the piston that acts directly on the brake pads. Because of the arrangement of the slave cylinder, heat from the brakes can be transferred back into the brake fluid.

Process IdentificationStandard motorcycle brake discs are mass produced on production lines using stamped parts made cheaply on production machinery. In mass production of product, we need to consider many aspect such as cost effectiveness, optimization of machine, accuracy of product, total production time and volume of scrap produce by the machine. Below are the step of producing brake discs from raw material. The surface grinding process is the process that we focus on.

Stamping process.Thick steel sheet rolled out from big coil is fed into stamping machine and the machine press out the steel sheet with massive force into circular shape blank. The blank then transfer to another stamping machine to punch out and produce the center shape of brake disc.Punching process.Punching machine punch all the brake disc holes with specific designed die. The function of hole on the surface of brake discs are to remove heat during the braking to ensure the brake function efficiently in high temperature. Punching machine also punch hole at the center of brakes disc to make slot for screw to mounted it to motorcycle wheel hub.Skimming process.The brake disc then transfer to the skimming machine to skimming the side and surface of the disc . This process remove the excess material that produce during stamping operation and to obtain the flatness of the disc and follow the given dimension . First quality control inspection.During the first quality control inspection, all the dimension and tolerance of brake disc are checked. For the product that have defect such as bend of not uniform dimension, adjustment must be made until the product achieve the requirement. If the defect is to serious such as crack, the product will be eliminate from the production line.Heat treatment process.Brake rotor that passed the quality control must undergo heat treatment, this process strengthened the steel by heat it until certain temperature. When reaching certain temperature, the furnace will inject carbon and the steel will absorb it for strengthen further. Quenching process.After exit the furnace, the brake rotors was quickly immerse in oil to quench it. Quenching process is a process of hardened the material to improve performance in high temperature during braking . steel can only having high hardness and excellent properties after quenching and after heat treatment is held at the tempering temperature.

Surface grinding process. This is the most crucial process in the manufacturing of brake discs, both surface of brake disc must be grinded to achieve ultrafine surface to ensure the brake disc give excellent performance during operation. Before grinding, the disc need to be mounted on fixture to prevent it from dislocate and need to be really fixed during grinding operation. The fixture must follow the entire requirement to produce excellent surface finishing surface product. The fixture must able to support the force exert on the brake disc due to perpendicular force from grinding wheel. During braking,disc brakeis a type ofbrakethat usescalipersto squeeze pairs ofpadsagainst adiscin order to createfrictionthat retards the rotation of a shaft, such as avehicleaxle, either to reduce its rotational speed or to hold it stationary. The energy of motion is converted intowaste heatwhich must be dispersed. To slow down the wheel, friction material in the form of brake pads, mounted on a device called a brake caliper, forced mechanical, hydraulic, pneumatic or electromagnetic toward both sides of the disc. Friction causes the disc and attached wheel to slow or stop. Brake convert motion into heat, and if the brakes to overheat, they become less effective, a phenomenon known as brake fade.Nowadays, many machine has equip with latest technology to achieve mass production and improve quality of the product. This CNC control disc grinding machine combines with hard industrial personal computer (PC), which is used to convey the motion control module. The motion controller is used, which sends command signals to / carrier servo drive axis control grinding fixture, available in versions compatible with any computer platform. Horizontal spindle or fixture are use to hold part, grinding machine are used to grind the surface by a "park and grind" method. An indexer "parks" the part between parallel grinding wheels. A servomotor is used to drive the indexer, which accelerates rapidly to park the parts, and it decelerates rapidly in removing them after grinding. To optimize surface finish and obtain necessary flatness, a "spin grinding" technique is used, by which the parts themselves rotate between the grinding wheels.

Final quality control inspection.After surface grinding process, the entire brake disc must undergo final quality inspection. Computer controlled CMM machines inspect every brake discs components for dimensional accuracy. The component also need to inspect using advanced optical inspection processes to ensure each component of brake discs meets tights quality control requirements from factory. One piece or more quantity of brake disc from one production batch will select to betested to determine their performance characteristics under different operating conditions. Test parameters may include repeated stops from high velocity, or extended driving cycles to measure wear life.

3.0 Tooling3.1 Type and purposeFixtures are functioning to hold, support and clamps workpieces. Grinding fixtures has been use as a tooling for doing surface finishing brake disc. The grinding process is usually a finishing operation where the work piece dimensions are held to close tolerances; therefore great accuracy is required in the design and construction of grinding fixture. Surface finishing brake disc is one of the important parts of manufacturing the brake disc. It used to get the finish length and thickness of the brake disc within precise tolerances. To get excellent surface finish, usually magnetic chuck is attached to the work rotating table of the grinder as the clamping. It also can help to fasten the load and unload of the brake disc. There are also help to maintain the accuracy of the thickness and no repeatability will occur thus can improve the mass production.In order to design a good fixture, it must be fulfil the requirement of 3-2-1 principle. In this system, three pins are located in the first plane, two in the second plane perpendicular to the first and one in the third plane. This prevents movement of 9 D.O.F (degree of freedom). Three locator under the workpiece restricts axial movement downward (z axis), two locators on the long edge, and one locator on the short edge.Magnetic clamp is usually consisting of electromagnetic chucks operated electrically. Permanent magnetic chuck uses mechanical lever to active the magnet. There are accessories used to fixture parts where these accessories allow the magnetic force to be transferred. Packing are used to fixed large parts with heavy tool force, or limited holding area of the workpiece.

3.2 Designing the fixture.To design surface grinding fixture of the disc brake, there are several step that must be followed to create one fixture that fulfil all the requirement that meet the industry standard and objective of creating the fixture. The following steps are the step of designing the fixture:

3.2.1 Designing the surface grinding fixture.a. Step1: Organizing all the relative information.Requirement:i. The material of the workpiece is hardened steel.ii. The material is cylindrical plate shape.iii. The thickness of the workpiece is 5mm.iv. The part received has been skimming and undergo heat treatment.v. The operation to be performed is surface grinding process.vi. Mass production fixture.vii. The fixture must able to maintain high accuracy and quality for high repeatability process.viii. The fixture should reduce production time and cost.b. Step 2: Gathering and analyze the information:

The following are the criteria that must be considered when designing jig and fixture:

c. Step 3: Identifying areas to support, locate, and clamp.

From the data gathered in the previous step, some conceptual design must be developed to solve the problem encountered and fulfill the requirement of fixture. Before develop the conceptual design, all the critical part such as support area,locator, and clamp must be identified to support and protect workpieces that will contribute toward precision machining.The concept was generated and few design are created without biased selective method as long as it need the requirements of a tooling as a jig and fixture.

Clamping and support area.Hole for locator

d. Step 4: Develop for Alternative Solution - Concept GenerationConcept GenerationIn this step, all concept design is unbiased and all idea that being visualised is taken into consideration. Every conceptual design has different locating, support and clamping mechanism. After that, the concept will be select according to many other variables for example the ease of manufacturability, ease of use, cost and many other variables that need to be considered taken. The figures below show three of design that has been created. Concept 1

Quick acting knobLocator SupportSlot for Milling tableFigure 3.1: Isometric view of concept 1.

Figure 3.2 : Orthographic projection of concept 1

Concept 2

Spinning fixture basesupportLocator pin Clamping boltFigure 3.3: isometric view of concept 2.

Locator pinClamping nut

Figure 3.4 : orthographic projection of concept

Locator pin for center hubConcept 3

Adjustable Magnetic clampSupportExtension for front and back surface center hub B.discAdjustable Locator pinFigure 3.5: isometric view of concept 3.

Figure 3.6: orthographic projection of concept 3

From the figures given, three conceptual design are generated to describe the basic concept under consideration for design surface grinding fixture to grind surface of brake discs. All of the concepts have their own ability and function.Concept 1 is the concept of turning grinding fixture consists of quick acting knob, locator pin and support. The fixture will be mounted on cylindrical grinding chuck. The function of locator pin is to guide the workpice accurately and precisely on the actual location. After locate the workpiece at the actual location, quick acting knob is use to clamp the workpiece tightly. The combinations of the support, locator and clamp are able to hold the part neatly. Concept 2 is the concept of indexing fixture which consists of fixture that will spin during surface grinding operation. The fixture will be attached on the surface grinding table tightly. Adjustable locating nut and bolt clamp are used to locate and clamp the brake disc. Disc brake are mounted on the flat support of the fixture itself for ease the surface grinding process happen without the work ability slow. Concept 3 is the combination concept of surface grinding fixture, magnetic clamp and adjustable locator pin. Brake disc is attached on the support by aided by freely spinning supporting center hub consist of two pin locator that align the center of brake disk respect to the center fixture. Center hubs have an extension that can be replace to do front and back brake disk surface grinding. Another two pin on the support table can be adjusted to meet the hole of variety type of brake disc and hold form moving. Magnetic clamping component also can be adjusted to clamp variety size of brake disc. Fixture is mounted on surface grinding spinning table.

e. Step 5 : Concept selectionConcept DescriptionSelection

Turning grinding fixture. 2 locator pin. Quick acting knob. Mounted on machine.Reject. Use lot of time to align the workpiece. Quick acting knob not suitable and can looses due to vibration.

Indexing fixture. Hold workpiece using adjustable nut and bolt clamp. Attach on flat machine table. Spinning during grinding operation.Reject. Accuracy and repeatability is low. High vibration during process. Lot of manual work.

Combination of surface grinding fixture, magnetic clamp and adjustable locator. 2 different type of locator pin use. Adjustable magnetic clamp Extension center hub can be replaced.Select. Fast loading and unloading time. High accuracy. Ergonomic. For variety shape and size. Hold workpiece securely.

3.4 JustificationType of fixture use:Grinding fixture has been choosing as it suitable and fulfils the requirement of 3-2-1 principle to do the surface finishing of the break disc. It widely used in industry to increase the mass production as well as to get a higher quality by get the finish lengths and thickness of the workpieces within precise tolerances.Adjustable magnetic clamp:Type of clamp use is magnetic clamp as it really suitable to use in the grinding surface machine. It helps to clamp the workpiece for not moving during the machining process working. It is also not give vibration to the workpiece while the process of machining runs.Adjustable locating pins:Locating position is made to bring the workpiece contact with the cutting tool prior to an excellent alignment. This locating pins will help the stability and location accuracy of the workpiece. Another two pin on the support table can be adjusted to meet the hole of variety type of brake disc and hold form moving.Extension for front and back surface center hub brake disc:Brake disc is attached on the support by aided by freely spinning supporting center hub consist of two pin locator that align the center of brake disk respect to the center fixture. Center hubs have an extension that can be replace to do front and back brake disk surface grinding. This will help to reduce time for loading and unloading of the workpiece.It also must be consider that the fixture only will be moving during the machining process not the cutting tools. This is because as the cutting tool move, it need a complex mechanism to do and make the machining process become hard. Fixture can be easily design as it follow the machining process and type of the processing.

The points that are taken into consideration for designing a product are as following: a. Jig must be so strong that the deflection in the jig should be as less as possible. The deflection that is mentioned includes the forces of cutting, clamping of workpiece to the machine table. The frame of the fixture should have sufficient mass to prevent vibrations during the machining of the job.b. Another important design consideration is the clamping which should be fast enough and require less amount of effort. c. Arrangement of clamps should be such that they are easily available. They should also have the arrangement for easy removal as well. d. Is swinging of clamp system is provided for removal of workpiece the clamp should swing as far as possible for unclamping the device. e. There should also be provision for easy removal of chip. This will prevent the interference of the chip with the operation on the workpiece i.e. cutting operation.f. The clamps and support points which are to be adjusted in due course of time should be preferred of same size. It will be better if the clamps and adjustable support points can be operated from the front of the fixture.g. If the surface area of clamping is more it damages the workpiece. This can be avoided by making the surface area of clamping as small as possible. h. As it is difficult to get spare parts during the operation so it is designed in such a way that they can be easily replaced on failure.i. The study of the design should be done thoroughly before fabricating. It should always be ensured that the work is done in proper sequence. This will ensure zero loss of material. It 12 should always be preferred that there is maximum operation in a single setting of the workpiece.j. The movement of the workpiece is restricted i.e. there is zero degree of freedom of the workpiece after clamping the workpiece. Sharp corners and redundant locators must be avoided. One should try to maintain at least one datum surface. k. The design must possess enough rigidity and robustness to prevent vibration else it may lead to undesired movement of the workpiece and tools.l. Minimum cost should be incurred during the fabrication of the project and the design should be as simple as possible. In such a way it will help even a lay man to operate the device.

ConclusionThere are many elements in jig and fixture in order to make sure it is always in good condition during used for machining processes. The definition and function of jig and fixture can describe overall about the task that this equipment do to help the machinist for easier works. Jigs and fixtures are manually or partially power operated devices. To fulfil their basic purposes, jigs and fixtures are comprised of several elements as it need base and body or frame with clamping features, locating elements for proper positioning and orientation of the blank, supporting surfaces and base, the clamping elements, and tool guiding frame and bushes (for jig).For the conclusion, the objective for this project are achieved and succeeded. The objective was to establish and hold the proper position of the parts throughout the surface finishing, to identify the related process, cutting tool and also machine tool of the part selected and lastly to improve the productivity of the manufacturing process of excellent surface grinding. After do this project, it give much benefit. Before this, some information and knowledge about jig and fixture are gained but exactly this assignment help to learn and understand more deeply about jigs and fixtures. This is because the jig and fixture is used widely in manufacturing field especially for machining so it is very useful to gain the knowledge about jig and fixture. In order to finish this assignment successfully, identifying the important thing about jigs and fixture have done. These main elements are specified carefully that is suitable for the jig and fixture design.

ReferencesJournal1) Brake disc and Process for producing the same (1978)Hiroma Okunishi, Sayamasi. Brake disc and Process for producing the same. Journal of Management.Vol 49(1), 1978.2) Is Magnetic Workholding For You? Modern Machine Shop (2000)Chris Koepfer. Is Magnetic Workholding For You? Modern Machine Shop. Article 2000

Internet1)http://www.stoptech.com/about/factory-tourFinal quality control of brake disk2)http://www.faqs.org/patents/app/20120125724#ixzz3XS9QonitManufacturing process of brake disc3) http://auto.howstuffworks.com/auto-parts/brakes/brake-types/disc-brake3.htmHow brake disc works4) http://www.counterman.com/brake-rotors-when-to-resurface-and-when-to-replace/The important of the surface finishing of break disc5) http://mikesbikes.com/how-to/disc-brake-basics-pg158.htmBasic about break disc technology6) http://www.totalmotorcycle.com/maintenance/brakes.htmBraking system of motorcycle

7) http://www.makeitfrom.com/material-data/?for=Cast-Iron. Cast Iron - Material Properties Data :MakeItFrom.com. 2014. Cast Iron - Material Properties Data :MakeItFrom.com.8) http://ebcbrakes.com/articles/how-to-make-brakes/. How to make brakes - EBC Brakes. 2014. How to make brakes - EBC Brakes

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