CHAPTER 1

INTRODUCTION

1.1 Project Title

The component shown in Figure 1.1 need to be drilled all holes and machined on the

surface marked. A suitable jig or jigs and a fixture or fixtures are required to be designed.

Use modular fixturing technique.

Figure 1.1: Component

1.2 Introduction to Tool Design

Tool design is the process of designing and developing the tools, methods, and

techniques necessary to improve manufacturing efficiency and productivity. Tool design

is also an integral part of the product-planning process, interacting with product design,

manufacturing, and marketing.

1.3 Tool Design Objectives

The main objective of tool design is to lower manufacturing costs while maintaining

quality and increased production. To accomplish this, the tool designer must satisfy the

following objectives:

i. Provide simple, easy-to-operate tools for maximum efficiency.

ii. Reduce manufacturing expenses by producing parts at the lowest possible cost.

iii. Design tools that consistently produce parts of high quality.

iv. Increase the rate of production with existing machine tools.

v. Design the tool to make it foolproof and to prevent improper use.

vi. Select the materials that will give adequate tool life.

vii. Provide protection in the design of the tools for maximum safety for operators.

CHAPTER 2

TOOL DESIGN

2.0 Tool Design

Tool design is the process of designing and developing the tools, methods, and

techniques necessary to improve manufacturing efficiency and productivity. It gives

industry the machines and special tooling needed for today’s high-volume production. It

is a specialized area of manufacturing engineering which comprises the analysis,

planning, design, construction and application of tools, methods and procedures

necessary to increase manufacturing productivity.

2.1 Creative Tool Design

Tool design is basically an exercise in problem solving. Creative problem solving ca be

described as a five-step process:

1. Defining Requirements

The new tooling might be required either for the first-time production of a new

product, or to improve production of an existing part. When improving and

existing job, the goal might be greater accuracy, faster cycle times, or both.

Tooling might be designed for one part, or an entire family.

2. Gathering and Analyzing Information

In the second design phase, all data is collected and assembled for evaluation. The

main sources of information are the part print, process sheets, and machine

specifications. When collecting this information, make sure that part documents

and records are current. Note taking is an important part of the evaluation process.

Complete and accurate notes allow designer to record an important information.

All ideas, thoughts, observations, and any other data about the part or tool are

then available for later reference. Good notes also minimize the chance that good

ideas will be lost.

Checklist for Design Considerations

Workpiece:

Size

Shape

Required accuracy

Material type

Material condition

Locating points

Locating stability

Clamping surfaces

Production quantity

Pending part-design revisions

Operations:

Types of operations

Number of separate operations

Sequence

Inspection requirements

Equipment:

Machine tools

Cutting tools

Special machinery

Assembly equipment and tools

Inspection equipment and tools

Equipment availability and scheduling

Plant space required

Personnel:

Safety equipment

Safety regulations and work rules

Economy of motion

Operator fatigue

Power equipment available

Possible automation

3. Developing Several Options

This requires the most creativity. A typical workpiece can be located and clamped

many different ways. An important strategy for successful tool design is

brainstorming for several good tooling alternatives, not just choosing one path

right away.

4. Choosing the Best Option

Choosing the best option is a cost or benefit analysis of different tooling option.

Some benefits, such as greater operator comfort and safety, are also important.

Other factors, such as tooling durability, are difficult to estimate. Cost analysis is

sometimes more of an art than a science.

5. Implementing the Design

The final phase of the tool-design process consists of turning the chosen approach

into reality. Final details are decided, final drawings are made, and the tooling is

built and tested.

Guidelines for Economical Design:

Use standard tooling components

The economics of standardized parts apply to tooling components as well

as manufactured products. Never build any component that you can buy.

Use prefinished materials.

Prefinished and performed materials should be used where possible to

lower costs and simplify construction.

Keep tolerances as liberal as possible

Tighter tolerances normally add extra cost to the tool with little benefit to

the process.

Simplify tooling operation.

Elaborate designs often add little or nothing to the function of the jig or

fixture. Reducing design complexity also reduces misunderstandings

between the designer and the machine operator.

The guidelines should be considered during the final-design process. Application

of these rules makes the work holder less costly, and improves its efficiency and

operation.

CHAPTER 3

JIGS AND FIXTURES

3.1 Introduction

The successful running of any mass production depends upon the interchangeability to

facilitate easy assembly and reduction of unit cost. Mass production methods demand a

fast and easy method of positioning work for accurate operations on it. Jigs and fixtures

are production tools used to accurately manufacture duplicate and interchangeable parts.

Jigs and fixtures are specially designed so that large numbers of components can be

machined or assembled identically, and to ensure interchangeability of components. In

order to do so, a jig or fixture is designed and built to support, hold, and locate every part

to ensure that each is drilled according to its specifications. Both terms are frequently

used incorrectly in shops. A jig is a guiding device and a fixture a holding device.

Jigs and fixtures are used to locate and hold the work that is to be machined.

These devices are provided with attachments for guiding, setting, and supporting the tools

in such a way that all the workpiece produced in a given jig or fixture will be exactly

identical in every way. The employment of unskilled labor is possible when jigs and

fixtures can be used in production work. A jig or fixture can be designed for a particular

job. The form to be used depends on the requirement and shape of the workpiece to be

machined.

3.2 Elements of Jigs and Fixtures

Generally, all the jigs and fixtures consist of the following elements:

i. Locating elements

Locating elements are used to establish and maintain the position of a workpiece

by constraining the movement of the workpiece. These position the workpiece

accurately with respect to the supporting elements tool in the jigs and fixtures. A

locating element is usually a fixed component and is used to establish, maintain

the position of a part by constraining the movement of the part. For workpiece of

greater variability in shapes and surface conditions, a locator can also be

adjustable.

ii. Clamping elements

Clamping elements hold the workpiece securely in the located position during

operation. A clamp is a force-actuating mechanism. The forces exerted by the

clamps hold a part securely against all other external forces.

iii. Tool guiding and setting elements

To aid the setting or guiding of the tools in the correct position with respect to the

workpieces.

3.2 Jigs

A jig is any of a large class of tools in woodworking, metalworking, and some other

crafts that help to control the location or motion (or both) of a tool. The primary purpose

for a jig is for repeatability and exact duplication of a part for reproduction. An example

of a jig is when a key is duplicated, the original is used as a jig so the new key can have

the same path as the old one. Since the advent of automation and CNC machines, jigs are

often not required because the tool path is digitally programmed and stored in memory.

The most-common jigs are drill and boring jigs. These tools are fundamentally the same.

The difference lies in the size, type, and placement of the drill bushings. Boring jigs

usually have larger bushings. These bushings may also have internal oil grooves to keep

the boring bar lubricated. Often, boring jigs use more than one bushing to support the

boring bar throughout the machining cycle.

Jig that expedites repetitive holes center location on multiple interchangeable

parts by acting as a template to guide the twist drill or other boring device into the precise

location of each intended holes center. In metalworking practice, typically a hardened

bushing lines each hole on the jig to keep the twist drill from cutting the jig as shown in

Figure 3.1. Jigs or templates have been known long before the industrial age. There are

many types of jigs, and each one is custom-tailored to do a specific job. Many jigs are

created because there is a necessity to do so by the trades men. Some are to increase

productivity, to do repetitious activities and to do a job more precisely.

Figure 3.1: Jig

Jigs may be divided into two general classes: boring jigs and drill jigs. Boring jigs

as shown in Figure 3.2 are used to bore holes that either is too large to drill or must be

made an odd size. Drill jigs are used to drill, ream, tap, chamfer, counterbore, countersink

and reverse. Basic jig is almost the same for either machining operation. The only

difference is in the size of the bushings used.

Figure 3.2: Boring Jig

3.3 Fixtures

Fixtures have a much-wider scope of application than jigs. These work holders are

designed for applications where the cutting tools cannot be guided as easily as a drill with

fixtures, an edge finder, center finder, or gage blocks position the cutter. Examples of the

more-common fixtures include milling fixtures, lathe fixtures, sawing fixtures, and

grinding fixtures. Moreover, a fixture can be used in almost any operation that requires a

precise relationship in the position of a tool to a workpiece.

Fixtures are essential elements of production processes as they are required in

most of the automated manufacturing, inspection, and assembly operations. Fixtures must

correctly locate a workpiece in a given orientation with respect to a cutting tool or

measuring device, or with respect to another component, as for instance in assembly or

welding. Such location must be invariant in the sense that the devices must clamp and

secure the workpiece in that location for the particular processing operation. There are

many standard work holding devices such as jaw chucks, machine vises, drill chucks,

collets, etc. which are widely used in workshops and are usually kept in stock for general

applications.

Fixtures are normally designed for a definite operation to process a specific

workpiece and are designed and manufactured individually. Jigs are similar to fixtures,

but they not only locate and hold the part but also guide the cutting tools in drilling and

boring operations. These work holding devices are collectively known as jigs and fixture.

Set blocks and feeler or thickness gauges are used with fixtures to reference the cutter to

the work piece. A fixture should be securely fastened to the table of the machine upon

which the work is done. Though largely used on milling machines, fixtures are also

designed to hold work for various operations on most of the standard machine tools.

Fixtures vary in design from relatively simple tools to expensive, complicated devices.

Fixtures also help to simplify metalworking operations performed on special equipment.

Fixtures are most often identified by the machine tool where they are used.

Examples include mill fixtures or lathe fixtures. But the function of the fixture can also

identify a fixture type. So can the basic construction of the tool. Thus, although a tool can

be called simply a mill fixture, it could also be further defined as a straddle-milling,

plate-type mill fixture. Moreover, a lathe fixture could also be defined as a radius-turning,

angle-plate lathe fixture. The tool designer usually decides the specific identification of

these tools. It use set blocks and thickness, or feeler, gages to locate the tool relative to

the workpiece as shown in Figure 3.3.

Figure 3.3: Set Block

Fixtures are normally classified by the type of machine on which they are used.

Fixtures can also be identified by a sub classification. For example, if a fixture is

designed to be used on a milling machine, it is called a milling fixture. If the task it is

intended to perform is straddle milling, it is called a straddle milling fixture. The same

principle applies to a lathe fixture that is designed to machine radii. It is called a lathe-

radius fixture.

The following is a partial list of production operations that use fixtures:

Assembling, lapping, boring, milling, broaching, planning, drilling, sawing, forming,

shaping, gauging, stamping, grinding, tapping, heat treating, testing, honing, turning,

inspecting and welding.

3.4 Advantages of Jigs and Fixtures

i. Productivity

Jigs and fixtures eliminate individual marking, positioning, and frequent

checking. This can reduce operation time and increase productivity. Two or more

workpieces can be machined simultaneously. Besides, jigs and fixtures enable

complex parts to be machined by being held rigidly to the machine.

ii. Interchangeability

Jigs and fixtures facilitate uniform quality in manufacturing. There is no need

of selective assembly. Any parts of the machine fit properly in assembly and all

similar components are interchangeable. Marking out and setting before

machining can be eliminated.

iii. Skill Reduction

Jigs and fixtures simplify locating and clamping of the workpieces. Tool

guiding elements ensure correct positioning of the tools with respect to the

workpieces, the make the use of lower skilled labor possible.

iv. Cost Reduction

Higher production, reduction in scrap, easy assembly and savings in labor

costs result in substantial reduction in the cost of workpieces produced with jigs

and fixtures. They decrease the expenditure on the quality controls of the

machine parts.

CHAPTER 4

MACHINING

4.0 Machining

Machining can me defined as the process of removing material from a workpiece in the

form of chips to removes unwanted material produce the desired shape. Most machining

has a very low set-up cost compared to forming, molding and casting processes.

However, machining is much more expensive for high volumes. Machining is necessary

where tight tolerances on dimensions and finished are required.

4.1 Drilling

Drilling is easily the most common machining process. Drilling involves the creation of

holes that are right circular cylinders. This accomplished most typically by using a twist

drill. The chip must exit through the flutes to the outside of the tool. This causing the

cutting front is embedded within the workpiece, making cooling difficult. The cutting

area can be flooded, coolant can be delivered through the drill bit shaft.

Figure 4.1: Drilling Machine

4.2 Milling

Milling is as fundamental as drilling among powered metal cutting processes. Milling is

versatile for a basic machining process, but because the milling set up as so many degrees

of freedom, milling is usually less accurate than turning and grinding unless especially

rigid fixturing is implemented.

Figure 4.2: Milling process at the cutting area

CHAPTER 5

SUPPORTS, LOCATORS AND BUSHINGS

5.1 Types of Support

5.1.1 Solid support

Solid support is the simplest type of support to use on tool base. This type of

support can be installed into the tool base. It is used when machined surface acts

as a locating point.

Figure 5.1: Rest Button

5.1.2 Adjustable Support

Adjustable support is used when the surface is rough or uneven. Normally used

with one or more solid locator to allow any adjustment needed to level the work.

Example: Screw Rest Button, Gripper Contact Bolts-Serrated Carbide Tipped,

Gripper Swivel Contact Bolts.

Figure 5.2: Screw Rest Button

Figure 5.3: Gripper Contact Bolts-Serrated Carbide Tipped

5.2 Types of Locator

5.2.1 Pin-type

Pin type locators are used for smaller holes and for aligning members of the tool.

It is a precision locating pins with a tapered tip foe easy loading and a shoulder to

resist downward forces.

Figure 5.4: Pin Type Locator

5.2.2 Diamond or Relieved Locator

Diamond pin is normally used along with the round pin to reduce the time it takes

to load and unload the tool. In use, the round pin locates the part and the diamond

pin prevents the movement around the pin.

Figure 5.5: Diamond Locator

Figure 5.6: Two locating pins mounted on a plate restrict the movement

5.2.3 Vee Locator

Vee locators are used mainly for round work. They can locate flat work with the

rounded or angular ends and flat discs. One advantage of vee locator is that it has

centralizing feature.

Figure 5.7: Vertical V block

Figure 5.8: Horizontal V Block

5.2.4 Fixed-Stop Locator

It is used for parts that cannot be placed in either a nest or a vee locator. They are

either machined into the tool body or installed.

Figure 5.9: Fixed-stop Locator

5.3 Type of Bushing

5.3.1 Renewable Bushing

Renewable bushing is generally used with linear bushing and lockscrew. There

are 2 types of renewable bushing, slip-renewable (Figure 5.10) and fixed-

renewable bushing (Figure 5.11). Fixed & slip renewable bushes are used where

more than one operation is performed in the same hole of the component, such as

drilling, and then reaming or counter boring. The renewable bush is held in place

by a locking screw .Lock screws are used with fixed and slips renewable bushes

to ensure that they do not turn or move during operation.

Figure 5.10: Slipe-renewable bushings

Figure 5.11: Fixed-renewable bushings

5.3.2 Press-Fit Bushings

There are 3 types of press-fit bushing, head, headless and serrated. It is

permanently pressed into the jig plate, usually flush with the top surface. They are

generally used for single-operation drilling or reaming. Headless bushings can be

mounted closer together than headed bushings, but offer less resistance to heavy

axial loads.

Figure 5.12: Headless bushing

Figure 5.13: Head bushing

Figure 5.14: Serrated bushing

5.3.3 Linear Bushing

There are 2 types of liner bushing, head and headless. Liners are permanent

bushings used to hold renewable drill bushings. They are used to provide a

hardened hole for renewable bushing. The liner's internal diameter has a precise

sliding fit with the renewable bushing's outer diameter. The liner accurately

locates the renewable bushing and protects the jig plate from wear and damage

caused by frequent bushing replacement.

Figure 5.15: Headless and head linear bushing

5.3.4 Template Bushing

An economical bushing designed for thin template jig plates from 1/16 to 3/8"

thick. Bushings are held in place by a Retainer. The outer diameter serrations

prevent the bushing from spinning. Bushings can be removed and reused by

breaking the Aluminum Retainer Ring.

Figure 5.16: Template bushing

5.3.5 Oil-Groove Bushing

Oil grooves are specially designed coolant passageways in a bushing's internal

diameter wall. Oil grooves are available on almost any bushing type, including

press fit, head press fit, and renewable. Use when you need complete drill

lubrication and cooling, such as when drilling hardened steel, or when bushings

are used as bearings. It is permit positive and complete lubrication of the bushing

for continuous high speed drilling operation.

Figure 5.17: press fit, head press fit, and renewable oil groove bushing

5.3.6 Knurled Bushing

This bushing is designed for cast-in-place or potted installation. Diamond-knurled

outer diameter provides excellent holding strength against both rotational and

axial forces. Since the bushing's OD is not ground, the internal diameter must be

accurately located during casting or potting to ensure accuracy in the finished

tool.

Figure 5.18: Knurled bushing

5.3.7 Serrated Bushing

This bushing can be cast in place or potted, just like a Diamond-Groove Bushing,

or can be pressed into an installation hole. The straight knurl provides excellent

resistance to rotation, but provides less resistance to axial forces than a diamond

knurl. Since the bushing's outer diameter is not ground, the internal diameter must

be accurately located during casting or potting to ensure accuracy in the finished

tool.

Figure 5.19: Serrated bushing

5.3.8 Chip-Breaker Bushing

Specially designed chip-breaking notches on the drill-exit end is use to break up

chips from tough, stringy materials, to reduce friction and heat build-up. Reduces

bushing wear at the drill-exit end and reduces the chance of tool or workpiece

damage. A chip-breaker bushing should extend beyond its liner to allow chips to

escape.

Figure 5.20: Chip-breaker bushing

CHAPTER 6

OPERATION

6.1 Operation Description

The part was formed by casting. To obtain the desired final product, further machining

processes need to be done. The operations listed below are to be carried out.

i. Drilling operations

a. Drilling two holes with ϕ 0.375 inches

b. Drilling a hole with ϕ 0.75 inches

ii. Milling operation 1

a. Milling of surface of two 0.375 inches holes

b. Milling of surface of two 3.500 x 0.800 inches

c. Milling of surfaces 2.500 x 0.800 inches

iii. Milling Operation 2

a. Milling of surfaces 3.500 x 2.500 inches

iv. Milling Operation 3

a. Milling of surfaces of 0.700 inches holes

Box Jig is used to perform the drilling operations. The box jigs is designed with

two identical bushings (two holes with ϕ 0.375 inches) and one other different bushing

(hole with ϕ 0.75 inches). Box jig is chosen because the part can completely machines on

every surface without the need to reposition the part in the jig. This can reduce time and

the inaccuracy caused by the reposition of the part.

Fixture 1 locates the part by using a round pin press-fit and a diamond pin press-

fit. This reduces the time it takes to load and unload the tool. The combination of round

pin and diamond pin can restrict eleven direction of movement of the workpiece. The last

vertical degree of freedom is restricted by using a customized angle plate. A customized

supporter is used to support the workpiece.

Fixture 2 utilizes the holes drilled in earlier process. A round pin and diamond pin

is used to restrict eleven direction of movement of the workpiece. A customized part with

a pin welded is used to restrict the last vertical direction of movement. This is because the

length of diamond and round pin with this diameter is not suitable for the design. Another

customized supporter is used to support the workpiece.

Fixture 3 is by used customized supporter so that is suitable with the design.

Socket head cap locator is used to clamp this supporter.

Drilling Operation

No. Part Standard

1. Head Press Fit Bushing H-40-8

2. Head Press Fit Bushing H-64-8

3. Knurled Head Screw CL-23207

4. Quarter Turn Screw CL-2-QTS

Milling Operation 1

No. Part Standard

1. Customized supporter -

2. Customized Angle-plate -

3. Press-fit Round Pin CL-374-RPT

4. Press-fit Diamond Pin CL-374-DPT

5. Socket Head Cap Screw CL-5/16-18X1.75SHCS

6. Shoulder Screw CL-35-SS

7. Washer CL-9-FW

8. Hex Nut CL-5-HN

9. Rectangular Tooling Plate CL-MF25-0150

Milling Operation 2

No. Part Standard

1. Customized Holder -

2. Customized Supporter -

3. Socket head Cap Screw CL-5/16-18X2.50SHCS

4. Diamond Pin CL-3-DPX

5. Round Pin CL-3-RP

6. Rectangular Tooling Plate CL-MF25-0150

Milling Operation 3

No. Part Standard

1. Customized Supporter -

2. Socket Head Screw CL-5/16-18X3.50SHCS

3. Rectangular Tooling Plate CL-MF25-0150

6.2 Tool

All the drill tool used are referred to the Arno catalogue. The tool used to drill ϕ 0.375

inch is HA950-1107-60SPW20. While the ϕ 0.75 hole is drilled using HI1753-2438-

118SPW25.

The milling cutter we use for this process is UNISL200 from metamasa catalog.

The diameter of the cutter is 20mm and the length is 141mm

6.3 Production Plan

PRODUCTION PLAN

P/N PART NAME QUANTITY ORDER NO

DRAWING NO PROCESS PLANNER REVISION NO DATE

19/11/12

PAGE 1 OF 1

OPERATION

NO

DESCRIPTION DEPT. MACH.TOOL

1

2

3

4

5

6

7

DRILL 2 ϕ0.375” HOLES THRU

DRILL ϕ0.75” HOLE THRU

MILL FACE 2 - Ø0.375 INCH TOP SURFACE

MILL END 2 – 0.800 x 3.500 INCH

MILL END 0.800 x 2.500 INCH

MILL FACE 3.500 x 2.500 INCH

MILL FACE 2 - Ø0.75 INCH TOP SURFACE

*10

DRILLING

*10

DRILLING

*20

MILLING

*20

MILLING

*20

MILLING

*20

MILLING

*20

MILLING

DRILL PRESS

*10-01

DRILL PRESS

*10-02

DRILL PRESS

*10-03

HORIZONTAL MILL

*20-10

HORIZONTAL MILL

*20-10

HORIZONTAL MILL

*20-10

HORIZONTAL MILL

*20-10

7

6

5

4

3

2

1

HORIZONTAL MILL CUTTER

HORIZONTAL MILL CUTTER

HORIZONTAL MILL CUTTER

HORIZONTAL MILL CUTTER

HORIZONTAL MILL CUTTER

DRILL

DRILL

Ø 20 MM

Ø 20 MM

Ø 20 MM

Ø 20 MM

Ø 20 MM

1.5”

1.5”

MODULAR

FIXTURE

MODULAR

FIXTURE

MODULAR

FIXTURE

MODULAR

FIXTURE

MODULAR

FIXTURE

TUMBLE BOX JIG

TUMBLE BOX JIG

TOOL DESCRIPTION SIZE SPECIAL TOOL NO.

7.0 Conclusion

As the conclusion, from this project, we learn more about tooling for production.

We must always design the simplest and easiest to operate tools for maximum

production. We also must use as much as possible the standard tools that does not need

for new design if available. We also learned that it is important to make a tool foolproof

to prevent improper use and to ensure correct dimension for the part. However, the safety

of the operators must also be taken seriously.In this project, we designed drilling

operations and milling operations in order to perform machining process to obtain the

final product.

APPENDICES

Standards Parts Used in Drilling Operations

1. Head Press Fit Bushing for ϕ 0.375”

2. Head Press Fit Bushing for ϕ 0.75”

3. Knurled Head Screw Clamp

4. Quarter Turn Screw

5. Φ0.375” inch Hole Drill Tool

6. Φo.75” Hole Drill Tool

Standards Parts Used in Drilling Operations

1. Rectangular Tooling Plate

2. Flat Washer

3. Hex Nut

4. Socket-Head Cap Screw

5. Shoulder Screw

6. Round and Diamond Pin

7. Press-Fit Round and Diamond Locator

8. Milling Cutter