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MANUFACTURING ENG. & PRODUCTION TECH. DEPARTMENT MINI CNC MACHINE (3 AXIS) Presented By: Amir Tawfic Dawa Mohamed Ahmed Abo yadak Ahmed Mohamed Ibrahem Mahmoud Abd El Wahab Ramy Abd El Aziz Waleed Fathy Hamed Supervised By: Prof. Dr. Abd El Naser Zayed July 2012 MODERN ACADEMY FOR ENGINEERING & TECHNOLOGY

Mini CNC (Router Machine)

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MANUFACTURING ENG. & PRODUCTION TECH. DEPARTMENT

MINI CNC MACHINE

(3 – AXIS)

Presented By:

Amir Tawfic Dawa

Mohamed Ahmed Abo yadak

Ahmed Mohamed Ibrahem

Mahmoud Abd El Wahab

Ramy Abd El – Aziz

Waleed Fathy Hamed

Supervised By:

Prof. Dr. Abd El Naser Zayed

July 2012

MODERN ACADEMY

FOR ENGINEERING & TECHNOLOGY

Table of Contents

CHAPTER (1)

INTRODUCTION ......................................................................................... 1

1.1 OVERVIEW ................................................................................................ 1

1.2 CNC SYSTEM ELEMENTS ...................................................................... 1

1.3 COMPUTER NUMERICAL CONTROL (CNC) ...................................... 2

1.4 STRUCTURAL MATERIALS FOR ROUTER ......................................... 2

1.5 CAD / CAM ................................................................................................ 2

1.6 COMPUTER AIDED MANUFACTURING ............................................. 3

1.7 COMPUTER AIDED DESIGN TYPES ..................................................... 4

1.8 MACHINING PROCESS ........................................................................... 5

1.8.1 Roughing .......................................................................................... 5

1.8.2 Semi-Finishing ................................................................................. 5

1.8.3 Finishing ........................................................................................... 6

1.8.4 Contour Milling ................................................................................ 6

1.9 ADVANTAGES OF CNC .......................................................................... 6

1.10 LIMITATIONS OF CNC .......................................................................... 7

CHAPTER(2)

DESIGN .......................................................................................................... 8

2.1 DETAIL DRAWING ........................................................................................... 8

2.2 SELECTION OF SPINDLE ............................................................................. 34

2.2.1 Select work piece and tool type ........................................................... 34

2.2.2 Calculate ( .................................................................................... 34

2.2.3 Calculate (N) ........................................................................................... 34

2.2.4 Calculate machine power ...................................................................... 34

2.2.5 Calculate material removal rate ........................................................... 35

2.2.6 Calculate efficiency factor (E) for m/c tool ....................................... 35

2.2.7 Calculate drive motor power ................................................................ 35

2.2.8 Calculate drive motor torque ................................................................ 35

2.3 ACTING FORCES : .......................................................................................... 37

2.4 DESIGN OF POWER SCREW ....................................................................... 37

2.4.1 TYPES OF POWER SCREW.............................................................. 37

2.5 CALCULATION OF POWER SCREW: ...................................................... 40

2.6 SELECTION OF BEARINGS ......................................................................... 45

2.6.1 PRINCIPLES OF OPERATION ........................................................ 45

2.6.2 MOTIONS ............................................................................................... 46

2.6.3 FRICTION ............................................................................................... 46

2.6.4 LOADS..................................................................................................... 46

2.6.5 SPEEDS ................................................................................................... 47

2.6.6 TYPES OF BEARING .......................................................................... 47

2.6.7 Calculation of Bearing ........................................................................... 48

2.7 DESIGN OF GUIDE WAY ............................................................................... 54

2.7.1 Linear Motion ......................................................................................... 54

2.7.2 Supporting Machine Components ....................................................... 54

2.7.3 Providing Precise Linear Motion......................................................... 54

2.7.4 Supporting Secondary Loads ............................................................... 54

2.7.5 Categories of Linear Motion systems ................................................. 56

2.7.6 Round rail bearings system................................................................... 57

2.7.7 Selection option ...................................................................................... 58

2.7.8 Linear bearing accuracy ........................................................................ 59

2.7.9 Calculation of guide way ...................................................................... 60

CHAPTER(3)

ASSEMBLY ................................................................................................... 78

CHAPTER(4)

CONTROL SYSTEM ................................................................................... 91

4.1 DEFINITION ............................................................................................ 91

4.2 CONROL PARTS ..................................................................................... 91

4.2.1 Controller ....................................................................................... 92

4.2.1.1 Types of Controller (Software) can be used ............................ 92

4.2.1.2 Features of Mach3 Software .................................................... 92

4.2.1.3 Configuration of Software ....................................................... 93

4.2.1.4 Determined Steps per Unit Length .......................................... 97

4.2.2 Power Supply ................................................................................. 99

4.2.3 Breakout Board Or Interface ......................................................... 99

4.2.3.1 Interface features ................................................................... 100

4.2.3.2 Parallel port ............................................................................ 100

4.2.3.3 Input and output ports ............................................................ 101

4.2.4 Motors driver ............................................................................... 101

4.2.4.1 Type of common driver circuits, ........................................... 101

4.2.4.2 Advantages of H-bridge and l297 circuit .............................. 102

4.2.4.3 Driver Circuit ......................................................................... 103

4.2.4.4 Driver PCB ............................................................................ 104

4.2.4.5 Driver Picture ......................................................................... 104

4.2.4.6 Machine Circuits Box ............................................................ 106

4.2.5 Motors .......................................................................................... 106

4.2.5.1 Motors type ............................................................................ 107

4.2.5.2 Open Loop Versus Closed Loop ........................................... 108

4.2.5.3 Stepper Motors Advantages And Disadvantages .................. 109

4.2.6 Switches ....................................................................................... 110

CHAPTER(5)

EXPERIMENTAL WORK AND VERIFICATION ............................... 111

5.1. MACHINING PARTS ............................................................................ 111

5.1.1. First Sample (Mdf) ...................................................................... 111

5.1.1.3. Machined Part ........................................................................... 112

5.1.1.4. G-Codes For First Sample ........................................................ 112

5.1.2. The Second Sample (MDF) ................................................................. 119

5.1.3. The Third Sample (From Aluminum) ................................................. 135

5.2. CONCLUSION ....................................................................................... 143

REFERENCES ............................................................................................. 144

Appendix ...................................................................................................... 145

CHAPTER (1)

INTRODUCTION

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CHAPTER 1

INTRODUCTION

1.1 OVERVIEW

The goal of this project to constrain, design, manufacturing, assemble for min

CNC milling machine tool and design and create the controller for it.

The process of manufacturing machined parts using a computerized

controller to command motors which drive each machine axis.

1.2 CNC SYSTEM ELEMENTS

A typical CNC system consists of six elements:

Part program

Program input device

Machine control unit

Drive system

Machine tool

Feedback system

Fig. ( 1.1 ) CNC System Elements

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1.3 COMPUTER NUMERICAL CONTROL (CNC)

Nowadays, products can be produced by modern technology, which uses

computer software, hardware and firm ware in industries. It is needed to use

CNC mill machine to get more accurate dimensions and irregular shape. End

milling is the most important milling operation, widely used in most of the

manufacturing industries due to its capability of producing complex geometric

surfaces with reasonable accuracy and surface finish. However, with the

inventions of CNC milling machine, the flexibility has been adopted along

with versatility in end milling process. In order to build up a bridge between

quality and productivity and to achieve the same in an economic way, the

present study highlights optimization of CNC end milling process parameters

to provide good surface finish and high material removal rate (MRR).

1.4 STRUCTURAL MATERIALS FOR ROUTER

The overall goal in constructing a CNC router machine is typically to have the

heavy immovable stationary portions to help reduce vibration. Another goal is

to have the movable parts be as light weight as possible (yet strong and stiff

enough to handle the intended loads). Thus, faster accelerations will be

possible because of lower inertia mass of the movable parts.

Wood Composites

Aluminum

1.5 CAD / CAM

Computer Aided Design (CAD) involves the use of computer hardware and

graphics software to generate design drawings. Modern CAD equipment

enables the designer to quickly produce very accurate and realistic images of

products to be manufactured. Computer Aided Manufacturing (CAM) is a

system of automatically producing finished products by using computer

controlled production machines. CAD and CAM work together in that the

digital model generated in CAD is inputted to the CAM software package.

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The CAM software needs to know the physical shape of the product (CAD

model) before it can compose a proper set of fabrication instructions to a

production machine.

1.6 COMPUTER AIDED MANUFACTURING

A computer aided manufacturing system allows the manufacturer to

systematically communicate work instructions to the machine. CAM has

evolved from a technology referred to as the Computer Numerical Control

(CNC), invented in the 1950s. CNC performed a set of coded instructions in a

punched paper tape.

Computer aided manufacturing facilitates effortless and quick computer

programming and faster execution of design changes. The computer aided

management system integrates the computer aided design systems and

controls tasks that involve order placement, scheduling, and replacement of

tools. The implementation of CAM system leads to overall increase in

efficiency of the manufacturing process. CAM systems are used in the

automotive, aviation and furniture manufacturing sectors and areas such as

mechanical engineering and electronic designing. Another significant benefit

of using the computer aided management system is that it allows

customization of the manufacturing process for creating client specific

designs.

A computer aided manufacturing system requires a 3D environment for

making it compliant with CAD systems. The CAM system can cost $18,000

or more along with the appropriate software. CAM allows automated

integration of the manufacturing procedure with other mechanization systems

such as Computer-Integrated Manufacturing (CIM), Integrated Computer-

Aided Manufacturing (ICAM), Flexible Manufacturing System (FMS), Direct

Numerical Control (DNC), and Manufacturing Process Management (MP).

Repetitive tasks involved in the manufacturing process are delegated to

machines using the CAM system, allowing workers involved to concentrate

on quality control and productivity.

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1.7 COMPUTER AIDED DESIGN TYPES

There are several different types of CAD. Each of these different types of

CAD systems requires the operator to think differently about how he or she

will use them and he or she must design their virtual components in a different

manner for each.

There are many producers of the lower-end 2D systems, including a number

of free and open source programs. These provide an approach to the drawing

process without all the fuss over scale and placement on the drawing sheet

that accompanied hand drafting, since these can be adjusted as required during

the creation of the final draft.

3D wireframe is basically an extension of 2D drafting (not often used today).

Each line has to be manually inserted into the drawing. The final product has

no mass properties associated with it and cannot have features directly added

to it, such as holes. The operator approaches these in a similar fashion to the

2D systems, although many 3D systems allow using the wireframe model to

make the final engineering drawing views.

3D "dumb" solids are created in a way analogous to manipulations of real

world objects (not often used today). Basic three-dimensional geometric

forms (prisms, cylinders, spheres, and so on) have solid volumes added or

subtracted from them, as if assembling or cutting real-world objects. Two-

dimensional projected views can easily be generated from the models. Basic

3D solids don't usually include tools to easily allow motion of components,

set limits to their motion, or identify interference between components.

3D parametric solid modeling requires the operator to use what is referred to

as "design intent". The objects and features created are adjustable. Any future

modifications will be simple, difficult, or nearly impossible, depending on

how the original part was created. One must think of this as being a "perfect

world" representation of the component. If a feature was intended to be

located from the center of the part, the operator needs to locate it from the

center of the model, not, perhaps, from a more convenient edge or an arbitrary

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point, as he could when using "dumb" solids. Parametric solids require the

operator to consider the consequences of his actions carefully.

Some software packages provide the ability to edit parametric and non-

parametric geometry without the need to understand or undo the design intent

history of the geometry by use of direct modeling functionality. This ability

may also include the additional ability to infer the correct relationships

between selected geometry (e.g., tangency, concentricity) which makes the

editing process less time and labor intensive while still freeing the engineer

from the burden of understanding the model’s.

1.8 MACHINING PROCESS

Most machining progresses through four stages, each of which is implemented

by a variety of basic and sophisticated strategies, depending on the material

and the software available.

The stages are:

1.8.1 Roughing

This process begins with raw stock, known as billet, and cuts it very roughly

to shape of the final model. In milling, the result often gives the appearance of

terraces, because the strategy has taken advantage of the ability to cut the

model horizontally. Common strategies are zigzag clearing, offset clearing,

and plunge roughing, rest-roughing.

1.8.2 Semi-Finishing

This process begins with a roughed part that unevenly approximates the model

and cuts to within a fixed offset distance from the model. The semi-finishing

pass must leave a small amount of material so the tool can cut accurately

while finishing, but not so little that the tool and material deflect instead of

shearing. Common strategies are raster passes, waterline passes, constant step-

over passes, pencil milling.

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1.8.3 Finishing

Finishing involves a slow pass across the material in very fine steps to

produce the finished part. In finishing, the step between one pass and another

is minimal. Feed rates are low and spindle speeds are raised to produce an

accurate surface.

1.8.4 Contour Milling

In milling applications on hardware with five or more axes, a separate

finishing process called contouring can be performed. Instead of stepping

down in fine-grained increments to approximate a surface, the work piece is

rotated to make the cutting surfaces of the tool tangent to the ideal part

features. This produces an excellent surface finish with high dimensional

accuracy.

1.9 ADVANTAGES OF CNC

Flexibility of operation is improved, as is the ability toproduce complex

shapes with good dimensional accuracy, repeatability, reduced scrap

loss, and high production rates, productivity, and product quality.

Tooling costs are reduced, since templates and other fixtures are not

required.

Machine adjustments are easy to make with microcomputers and digital

readouts.

More operations can be performed with each setup, and less lead time

for setup and machining is required compared to conventional methods.

Design changes are facilitated, and inventory is reduced.

Programs can be prepared rapidly and can be recalled at any time

utilizing microprocessors. Less paperwork is involved.

Faster prototype production is possible.

Required operator skill is less than that for a qualified machinist, and

the operator has more time to attend to other tasks in the work area.

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1.10 LIMITATIONS OF CNC

Relatively high initial cost of the equipment.

The need and cost for programming and computer time.

Special maintenance with trained personnel.

High preventative maintenance since breakdowns are costly.

CHAPTER (2)

DESIGN

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CHAPTER 2

DESIGN

2.1 DETAIL DRAWING

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THE SPECIFICATION:

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2.2 SELECTION OF SPINDLE

2.2.1 Select work piece and tool type

Work piece…Aluminum

Tool………...shank end mill Φ40 (high speed steel)

2.2.2 Calculate (

f ……feed

Range of from 150 to 360 [ ⁄ ]

Range of feed from 0.12 to 0.3

2.2.3 Calculate (N)

(2.1)

N…..rotational speed

D….diameter of tool

N=

2.2.4 Calculate machine power

c….feed factor

C= from 1 to 1.2

w….tool wear factor

w= from 1.1 to 1.25 for light and medium milling

For Aluminum

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2.2.5 Calculate material removal rate

(2.2)

d….depth of cut d=2

w….width of cut w=40

f….feed rate f=0.3

*

⁄ +

2.2.6 Calculate efficiency factor (E) for m/c tool

For direct and belt drive E=0.9

2.2.7 Calculate drive motor power

(2.3)

2.2.8 Calculate drive motor torque

(2.4)

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2.3 -ACTING FORCES :

Fig. (2.2) Acting Forces

(2.5)

t Depth of cut

t = 2

feed per tooth

0.86 0.72 0.018 – 0.08

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2.4 DESIGN OF POWER SCREW

Power Screws are used for providing linear motion in a smooth uniform manner. They are linear actuators that transform rotary motion into linear motion. Power screws are are generally based on Acme , Square, and Buttress threads. Ball screws are a type of power screw. Efficiencies of between 30% and 70% are obtained with conventional power screws. Ball screws have efficiencies of above 90%. Power Screws are used for the following three reasons

To obtain high mechanical advantage in order to move large loads with minimum effort. e.g Screw Jack.

To generate large forces e.g A compactor press. To obtain precise axial movements e.g. A machine tool lead screw.

2.4.1 TYPES OF POWER SCREW

2.4.1.1 Square Form

This form is used for power/force transmission i.e. linear jacks,

clamps. The friction is low and there is no radial forces imposed on the

mating nuts. The square thread is the most efficient conventional power

screw form. It is the most difficult form to machine. It is not very

compatible for using split nuts-as used on certain machine tool system for

withdrawing the tool carriers

Fig. (2.3) Square Form

2.4.1.2 Acme Form

Used for power transmission i.e. lathe lead screws. Is easier to manufacture compared to a square thread. It has superior root strength characteristics compared to a square thread. The acme screw thread has been developed for machine tool drives. They are easy to machine and can be used with split

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nuts. The thread has an optimum efficiency of about 70% for helix angles

between 25o and 65o. Outside this range the efficiency falls away.

Fig. (2.4) Acme Form

2.4.1.3 Buttress Form

A strong low friction thread. However it is designed only to take large

loads in on direction. For a given size this is the strongest of the thread

forms. When taking heavy loads on the near vertical thread face this thread

is almost as efficient as a square thread form.

Fig. (2.5) Buttress Form

2.4.1.4 Recirculating Ball Screw

This type of power screw is used for high speed high efficiency

duties. The ball screw is used for more and more applications previously

completed by the conventional power screws.

The ball screw assembly is as shown below and includes a circular shaped

groove cut in a helix on the shaft. The ball nut also includes an internal

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circular shaped groove which matches the shaft groove. The nut is

retained in position on the shaft by balls moving within the groove. When

the nut rotates relative to the shaft the balls move in one direction along

the groove supporting any axial load. When the balls reach one end of the

nut they are directed back to the other end via ball guides. The balls are

therefore being continuously recirculated.

Fig. (2.6) Recirculating Ball Screw

The recirculated ball screw has the following advantages and

disadvantages to the conventional threaded power screws:

Advantages

High Efficiency - Over 90%

Predictable life expectancy -

Precise and repeatable movement

No tendency for slip-stick

Minimum thermal effects

Easily preloaded to eliminate backlash-with minimum friction

penalty

Smoother movement over full travel range

Smaller size for same load

Disadvantages

Requires higher levels of lubrication

Tend to overhaul- Needs additional brakes if locking is required

Susceptible to contamination

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For the same capacity ball screws are not as rigid as conventional

power screw

2.4.1.5 Roller Screw

A recent high specification power screw option is the roller screw. For

this unit the nut includes a number of special threaded rollers arranged

around arround the central screw. The rollers each take a part of the

load. This system is efficient and can withstand high loads.

2.5 CALCULATION OF POWER SCREW:

(2.6)

(2.7)

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Design for strength :

(2.8)

(2.9)

{ }

(2.10)

{ }

(2.11)

Power screw is safe

Design against buckling :

(2.12)

Q <

Power screw is safe

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y –axis:

(2.13)

(2.14)

<

power screw is safe

Design for strength :

(2.15)

{ }

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< { }

Power screw is safe

Design against buckling :

(2.16)

Q <

Power screw is safe

x –axis :

<

power screw is safe

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Design for strength :

(2.17)

(2.18)

{ }

< { }

Power screw is safe

Design against buckling :

Q <

Power screw is safe

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2.6 SELECTION OF BEARINGS

A bearing is any of various machine elements that constrain the relative

motion between two or more parts to only the desired type of motion. This

is typically to allow and promote free rotation around a fixed axis or

free linear movement; it may also be to prevent any motion, such as by

controlling the vectors of normal forces. Bearings may be classified

broadly according to the motions they allow and according to their

principle of operation, as well as by the directions of applied loads they

can handle.

2.6.1 PRINCIPLES OF OPERATION

Fig. (2.7) PRINCIPLES OF OPERATION

There are at least six common principles of operation:

plain bearing, also known by the specific styles: bushings, journal

bearings, sleeve bearings, rifle bearings

rolling-element bearings such as ball bearings and roller bearings

jewel bearings, in which the load is carried by rolling the axle

slightly off-center

fluid bearings, in which the load is carried by a gas or liquid

magnetic bearings, in which the load is carried by a magnetic field

flexure bearings, in which the motion is supported by a load element

which bends.

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2.6.2 MOTIONS

Common motions permitted by bearings are:

axial rotation e.g. shaft rotation

linear motion e.g. drawer

spherical rotation e.g. ball and socket joint

hinge motion e.g. door, elbow, knee

2.6.3 FRICTION

Reducing friction in bearings is often important for efficiency, to reduce

wear and to facilitate extended use at high speeds and to avoid overheating

and premature failure of the bearing. Essentially, a bearing can reduce

friction by virtue of its shape, by its material, or by introducing and

containing a fluid between surfaces or by separating the surfaces with an

electromagnetic field.

By shape, gains advantage usually by using spheres or rollers, or by

forming flexure bearings.

By material exploits the nature of the bearing material used. (An

example would be using plastics that have low surface friction.)

By fluid exploits the low viscosity of a layer of fluid, such as a

lubricant or as a pressurized medium to keep the two solid parts

from touching, or by reducing the normal force between them.

By fields exploits electromagnetic fields, such as magnetic fields, to

keep solid parts from touching.

Combinations of these can even be employed within the same bearing. An

example of this is where the cage is made of plastic, and it separates the

rollers/balls, which reduce friction by their shape and finish.

2.6.4 LOADS

Bearings vary greatly over the size and directions of forces that they can

support.

Forces can be predominately radial, axial (thrust bearings) or bending

moments perpendicular to the main axis.

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2.6.5 SPEEDS

Different bearing types have different operating speed limits. Speed is

typically specified as maximum relative surface speeds, often specified ft/s

or m/s. Rotational bearings typically describe performance in terms of the

product DN where D is the diameter (often in mm) of the bearing and N is

the rotation rate in revolutions per minute.

Generally there is considerable speed range overlap between bearing

types. Plain bearings typically handle only lower speeds, rolling element

bearings are faster, followed by fluid bearings and finally magnetic

bearings which are limited ultimately by centripetal force overcoming

material strength.

2.6.6 TYPES OF BEARING

There are many different types of bearings

Needle Bearing

Cylindrical Bearing

Sleeve Bearing

Spherical Bearing

Linear Bearing

Roller Bearing

Fig. (2.8) Types Of Breaing

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2.6.7 Calculation of Bearing

Z-axis

(x-z) plan :

Ʃ

Ʃ (2.20)

(y-z ) plan :

Ʃ

( )

Ʃ

( )

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At bearing B

(2.21)

(2.23)

(

) (2.24)

,

(

)

at , , ,

At bearing (A)

(

)

(

)

at , , ,

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The bearing is safe

X-axis :

(x-z plan) :

(x-y plan) :

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At bearing B

Back to back:

(

)

(

)

, ,

At bearing A:

(

)

(

)

, ,

The bearing is safe

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Y-axis

x- y plan

X-Z plan

566 ( 70 ) – 147 ( 88 ) =

147 ( 88 ) + 566 ( 70 ) =

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At bearing B

Back to back

(

)

= (0.4 * 107.1) + 2.1 (

= 200.51 [N]

(

)

(

)

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2.7 DESIGN OF GUIDE WAY

2.7.1 Linear Motion

The LM system is responsible for three primary tasks

1. Support machine components.

2. Guide the machine in a precise linear motion with minimal friction.

3. Support secondary loads (Torque, Lateral loads, etc).

Fig. (2.9) Linear Motion

2.7.2 Supporting Machine Components

The LM system must be able to handle the weight of the components

while transporting it along a linear distance and maintaining linearity . For

example, the gantry on a CNC router is supported on a LM system and is

able to move along the X- axis. The LM system must support the weight

of the gantry and still provide allow friction motion.

2.7.3 Providing Precise Linear Motion

While supporting a load, the LM system must also provide a precise linear

motion with minimal friction. This is the primary task of a LM system.

The type of LM system directly related to the accuracy or a CNC router. A

‘‘sloppy’’ linear motion system leads to a ‘‘sloppy’’ CNC machine. That

is why it is important to have the correct LM system installed on each axis.

2.7.4 Supporting Secondary Loads

A side from supporting the weight of the machine, LM systems must also

be able to Support secondary loads such as torque or lateral loads,

depending on the setup. Some applications of LM systems require only

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one dimensional load ratings, such as supporting a vertical load like

weight. Other applications require multi-dimensional load ratings. For

example, the LM system of the CNC router is required to support the

vertical loads caused by the weight of the Z-axis assemble, and also

support torsion forces cause by the cutting action. We will cover more on

load ratings in later sections.

Every LM system is rated for certain loads and certain applications.

Choosing or identifying the right system for your CNC router is a vital

ability to have when buying or building.

2.7.5 Categories of Linear Motion systems

If you could categorize linear motion systems into 2 categories it would

be:

1. Fully Supported Systems

2. Partially/End Supported Systems

Fully supported LM systems are supported throughout the entire length of

the system. This type of system can usually support more lead without

sacrificing linear precision due to deflection. A quality CNC router will

have fully supported LM systems on all axes. Some mid or low range

machines use fully supported systems on the X and Y-axis while using end

supported systems on the Z-axis. As the length of the axis increases the

more vital it is to have fully supported systems. Examples of these

systems include linear rails and guide blocks as well as track rollers.

Partially or end supported LM systems are just what they seam. These

systems are supported on their ends. These systems are due to flex and

deformation because of the machine weight or the forces applied.

However, these systems are more suitable in some applications. The most

common type of end supported of LM systems is the linear rod and

bushing setup.

Of course each category contains many different types of linear motion

system which will be covered in their respective sections.

There are several advantages of linear guide systems. For starters, they are

very robust and accurate due to their construction. Most all guide block

systems use ball bearings to roll the load along the rail, which means high

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efficiency. This high efficiency means less work must be done by the drive

system to move the load.

Rolling element linear-motion bearings guide, supported, locate and

accurately move the machinery components and productizes. Rolling

element linear bearings and guides ensure low friction, smooth, accurate

motion for nearly any moment or normal loading condition.

Understanding the tradeoffs of each bearing type is important to accurately

size and select not only the right bearing, but also the right integrated

controls and components for the application. The right choice ensures

machine accuracy, repeatability, and life.

Fig. (2.10) Categories of linear motion system

You have a range of bearing and guide alternatives for accurate linear

motion. For example, bronze bushings have high load capacity and low

accuracy while profile rail linear guides have high load capacity and

medium accuracy. Linear rolling element bearings are used in most critical

industrial application. They generate much less friction than sliding

bearings so they can use a smaller motor and drive system and can run at

considerably higher speeds. Linear rolling bearings also eliminate the

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stick-slip effect that often causes chatter. They offer a predictable life and

do not lose tolerance over their lives.

2.7.6 Round rail bearings system

The two major types of linear guides are not rail bushing bearings and

profile rail bearings. Round rail ball bushing bearing systems

accommodate torsion misalignment caused by inaccuracies in carriage or

base machining or machine deflection with little increase in stress to the

bearing components. The self-aligning-in-all-directions design is forgiving

of poor parallelism and variations in rail height. These bearings allow for

smooth travel when mounted to wider-tolerance prepared surfaces.

This chart shows the comparative strength of different types of bearings in

end-supported applications, you establish the axis of motion of round rail

guides by fixing the two ends of the shaft. It doesn't matter what surface of

the machine is like between these two points or whether there is one at all.

So round linear bearings can span gaps up to 24 times the shaft diameter,

making them useful in arrange of applications such as pick-end-place

modules and gantry systems. The accuracy of the guide depends only on

the accuracy of the end-support mounting.

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Examples of round rail ball bushing bearing component

Fig. (2.11)

Traditional precision steel round rail bearings provide point contact on the

inner and outer race so they are very low friction, and they offer a

relatively lower load capacity. A more sophisticated design of round rail

ball bushing offers a ball conforming groove on the outer race maintains

point contact on the inner race. This design offers a 3X increase in load

capacity. A more advanced design uses universal self-aligning dual tracks

for a 6X increase in load capacity. The load capacity increase is achieved

by maximize the load reaction between the inner and outer races. This

breakthrough rivals that of linear guides while still retaining the

advantages of the round rail design that enable the linear bearing to avoid

many of the dating factors that can diminish load/life performance of

square rail products.

2.7.7 Selection option

The sizing and selection process is similar but not exactly the same for

round and profile rail bearings. Loads acting on linear bearings and guided

can be vertical loads, horizontal loads or pitch roll or yaw moment loads,

or any combination thereof. Loads may also very in their magnitude and

direction. A resultant load vector at each bearing must be established from

the combination of the various load vectors to which the linear bearing

system load vectors. The load under which each linear bearing is

subjected is called the dynamic equivalent load for that given bearing. The

system is then sized based on the most heavily loaded bearing. For more

information on computation methods for a dynamic equivalent load, refer

to the linear bearing and guide suppliers catalogues.

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Fig. (2.12) Selection option

Roller rail bearings can handle higher loads compared to ball profile rail

bearings because of the greater contact surface .Machine builders can

downsize from atypical ball profile rail assembly to a smaller roller

assembly without compromising load capacity.

2.7.8 Linear bearing accuracy

Linear bearing accuracy is defined as the variation in height over the

length of the travel. The best achievable accuracies for 120 in. rail length

are +/-0.0008 in. for round rail bearings and +/-0.0001 in. for profile rails.

In applications where running accuracy is critical, profile rail bearings

typically can offer better accuracy than inch round rail bearings. Supper or

ultra accuracy class profile rail bearings offer improved accuracy

compared to standard profile rail bearings.

Fig. (2.13) Linear Bearing Accuracy

Accuracy can also be improved by machining the mounting surface to a

higher flatness tolerance and through the addition of a reference edge.

Bearing preload is used in both round and profile rail bearings to minimize

deflection be removing any internal clearance in the bearing. This preload

develops by generating an interference fit between the outer race, rolling

elements, and inner race of the bearing. The heavier the preload in the

bearing, the smaller the initial carriage-to-rail deflection. You can achieve

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preload in a rail round bearing by adjusting or using an undersized housing

bore or an oversized 60case shaft. Be careful not to over-preload the

bearing as this could negatively affect the function of the bearing. Preload

in a profile rail is set in the factory by using oversized rolling elements.

2.7.9 Calculation of guide way

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Guide (1) (Z-axis)

, ] , ,

, ,

W = 5 [kg]

Y-z plan

(2.25)

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]

At point (A)

]

At point (B)

]

Moment

]

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X-Z Plan

(2.26)

(2.27)

]

At point A

(-848.7 * 113) + (848 * 166) =

]

At point B

( 848.7 * 83 ) – ( 848.7 * 30 ) =

]

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Moment

]

M =√

=

(2.28)

Guide ( 2 ) (x- axis)

, ,

, W = 10 [kg]

(

) (2.29)

(

) (2.30)

(

)

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x-z plan

At point (A)

]

At point (B)

Moment

x-y plan

(2.31)

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(2.32)

At point (A)

(393.23 * 245 ) – (393.23 * 131 ) =

(393.23 * 204 ) – ( 393.23 * 90 ) =

Moment

√ = 21.27

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σ =

n =

Guide (3) (y-axis) :

X-Y plan

(

) (2.33)

(

) (2.34)

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At point A

(111.64 * 454.5 ) – (111.64 * 330.5 ) =

At point B

( - 111.64 * 50.5 ) + (111.64 * 174.5 ) =

Y-Z plan

(

) (2.35)

(

)

= 396.47 N

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At point A

( 467.6 * 454.5 ) – ( 467.5 * 330.5 ) =

At point B

( 467.6 * 174.5 ) – ( 467.6 * 50.5 ) =

Moment

=

σ

σ =

n =

2.7.9.1 Design of Guide Way Against Deflection

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Y=

(

)

(2.36)

(2.37)

E=207 GPa = 207000 [N/

]

= 1017.88

Guide ( 1 ) ( Z-axis )

y-z plan

M = F *

= 772.52 *

= 20471.78 [N.mm]

[

]

*

+

At

X = 39.2 [mm] y = -.102 [mm]

X = 58.8 [mm] y = - 0.154 [mm]

X = 78.4 [mm] y = -0.1807 [mm]

X = 98 [mm] y = -0.185 [mm]

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X = 117.6 [mm] y = -0.166 [mm]

X = 137.2 [mm] y = -0.1406 [mm]

X = 156.8 [mm] y = -0.0999 [mm]

X = 176.4 [mm] y = -.0519 [mm]

X = 196 [mm] y = 0 [mm]

X-Z Plan

=

(

)

M = F *

= 848.7*

=22490.55 [N.mm]

[

]

At

X = 19.6 [mm] y = -0.155 [mm]

X = 39.2 [mm] y = -0.1122 [mm]

X = 58.8 [mm] y = -0.17 [mm]

X = 78.4 [mm] y = -0.199 [mm]

X = 98 [mm] y = -0.2034 [mm]

X = 117.6 [mm] y = -0.1825 [mm]

X = 137.2 [mm] y = - 0.1549 [mm]

X = 156.8 [mm] y = -0.11 [mm]

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X = 176.4 [mm] y = -0.0577 [mm]

X = 196 [mm] y = 0 [mm]

Y=√

(2.38)

Y = 0.1563 [mm]

Y = 0.023 [mm]

Y = 0.2294 [mm]

Y = 0.2688 [mm]

Y = 0.2749 [mm] (maximum deflection)

Y = 0.2467 [mm]

Y = 0.2092 [mm]

Y = 0.1486 [mm]

Y = 0.0776 [mm]

Y = 0 [mm]

When we use linear bearing D=12 maximum deflection =0.2749 mm

Guide (2) ( X-axis )

X-Z Plan

=

(

)

M = F *

= 728.62*

= 41531.34 [N.mm]

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[

]

At

X = 33.5 [mm] y = 0.0104 [mm]

X = 67 [mm] y = -0.492 [mm]

X = 100.5 [mm] y = -0.8173 [mm]

X = 134 [mm] y = -0.988 [mm]

X = 167.5 [mm] y = -1.0262 [mm]

X = 201 [mm] y = -0.9535 [mm]

X = 234.5 [mm] y = -0.7923 [mm]

X = 268 [mm] y = -0.565 [mm]

X = 301.5 [mm] y = -0.2395 [mm]

X = 335 [mm] y = 0 [mm]

X-Y Plan

=

(

)

M = F *

= 393.23 *

= 22414.11 [N.mm]

[

]

At

X = 33.5 [mm] y = 0.0056 [mm]

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X = 67 [mm] y = -0.2654 [mm]

X = 100.5 [mm] y = -0.4409 [mm]

X = 134 [mm] y = -0.5329 [mm]

X = 167.5 [mm] y = -0.5535 [mm]

X = 201 [mm] y = -0.5143 [mm]

X = 234.5 [mm] y = -0.4274 [mm]

X = 268 [mm] y = -0.3047 [mm]

X = 301.5 [mm] y = -0.1583 [mm]

X = 335 [mm] y=0 [mm]

Y=√

Y = 0.0118 [mm]

Y = 0.559 [mm]

Y = 0.9286 [mm]

Y = 1.1226 [mm]

Y = 1.166 [mm] (maximum deflection)

Y = 1.0834 [mm]

Y = 0.9002 [mm]

Y = 0.6419 [mm]

Y = 0.3335 [mm]

Y = 0 [mm]

When use linear bearing D=12mm max deflection = 1.166 [mm]

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Guide ( 3 ) ( Y-axis )

x-y plan

=

(

)

M=F *

= 111.64*

=6921.68 [N.mm]

[

]

At

X = 50.5 [mm] y = -0.0982 [mm]

X = 101 [mm] y = -0.277 [mm]

X = 151.5 [mm] y = -0.389 [mm]

X = 202 [mm] y = -0.4423 [mm]

X = 252.5 [mm] y = -0.4453 [mm]

X = 303 [mm] y = -0.4065 [mm]

X = 353.5 [mm] y = -0.3343 [mm]

X = 404 [mm] y = -0.2367 [mm]

X = 454.5 [mm] y = -0.1226 [mm]

X = 505 [mm] y = 0 [mm]

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y-z plan

=

(

)

M = F *

= 467.6 *

= 28991.2 [N.mm]

[

]

At

X = 50.5 [mm] y = -0.4111 [mm]

X = 101 [mm] y = -1.1594 [mm]

X = 151.5 [mm] y = -1.6282 [mm]

X = 202 [mm] y = -1.8512 [mm]

X = 252.5 [mm] y = -1.8638 [mm]

X = 303 [mm] y = -1.7013 [mm]

X = 353.5 [mm] y = -1.3991 [mm]

X = 404 [mm] y = -0.9909 [mm]

X = 454.5 [mm] y = -0.5132 [mm]

X=505 [mm] y = 0 [mm]

`Y=√

Y = 0.4227 [mm]

Y = 0.732 [mm]

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Y = 0.632 [mm]

Y = 0.554 [mm]

Y = 1.175 [mm] (maximum deflection)

Y = 0.792 [mm]

Y = 0.245 [mm]

Y = 1.0188 [mm]

Y = 0.5276 [mm] Y = 0 [mm]

When we use linear bearing D=12mm maximum deflection = 1.175

[mm]

CHAPTER (3)

ASSEMBLY

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CHAPTER 3

ASSEMBLY

1. Assemble parts on x-axis plate

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2. Sub assembly of x -axis

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3. Assemble parts on z axis plate

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4. Sub assembly of z axis

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5. Assemble sub assembly of z- axis and sub assembly of x axis

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6. Assemble left hand side with stepper motor

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7. Sub assembly of left hand side

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8. Assemble sub assembly of left hand side with sub assembly of Z-

axis and Y-axis

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9. Assemble the previous sub assembly with right hand side

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10. Sub assembly of two side and sub assembly of Z-axis and X-axis

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11. Assemble the back base

12. Sub assembly of back base

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13. Assemble the sub assembly of back base and front with

previous sub assembles

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1- Main assembly of machine

CHAPTER (4)

CONTROL

SYSTEM

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CHAPTER 4

CONTROL SYSTEM

4.1 DEFINITION

The CNC controller is the brain of a CNC system. A controller completes the

all-important link between a computer system and the mechanical components

of a CNC machine. The controller's primary task is to receive conditioned

signals from a computer or indexer and interpret those signals into mechanical

motion through motor output. There are several components that make up a

controller and each component works in unison to produce the desired motor

movement.

The word “controller” is a generic term that may refer to one of several

devices, but usually refers to the complete machine control system. This

system may include the protection circuitry, stepper or servo motor drivers,

power source, limit switch interfaces, power controls, and other peripherals.

4.2 CONROL PARTS

1 Controller

2 Power supply unit

3 Breakout board or interface

4 Motors driver

5 Motors

6 Switches

Fig.4.1 control parts

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4.2.1 Controller

The CNC controller is the brain of a CNC system. A controller completes the

all-important link between a computer system and the mechanical components

of a CNC machine. The controller's primary task is to receive conditioned

signals from a computer or indexer and interpret those signals into mechanical

motion through motor output. There are several components that make up a

controller and each component works in unison to produce the desired motor

movement.

Controllers still require operators to create a program for the controller to

follow. Operators today receive help from Software such as Computer-Aided

Design (CAD) packages and Computer-Aided Manufacturing (CAM)

software along with the controller software to create the necessary numerical

code such as G-code

The Controller unit replaced by software controller which can be run from

Computer

4.2.1.1 Types of Controller (Software) Can Be Used

a) Mach3

b) K Cam

c) other

The controller used is mach3 software. Mach3 is a software package which

runs on a PC and turns it into a very powerful and economical Machine

Controller to replace Controller unit.

4.2.1.2 Features of Mach3 Software

a) Converts a standard PC to a fully featured, 6‐axis CNC controller.

b) Allows direct import of DXF, BMP, JPG, and HPGL files through

LazyCam.

c) Visual G‐code display.

d) Generates G‐code via LazyCam or Wizards.

e) Contain many common cycles shown in Fig.4.2

f) Fully customizable interface.

g) Spindle Speed control.

h) Multiple relay control.

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4.2.1.3 Configuration of Software

1. To configure output ports open (Config) – (Ports and Pins), as shown in

Fig.4.3

Fig.4.2 selection of operation

Fig.4.3 configuration menu

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2. The following screen will appear in Fig4.4 Check (Port Enabled) box and

set the port No. to 0x378.

3. Select (Motor Outputs) tab as shown in Fig.4.5 Enable the required axis

and set Step Pin# and Dir Pin# as shown in figure

Fig.4.4 ports configuration

Fig.4.5 motor output configuration

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4. Select (Output Signals) as shown in figure and assign pin number for each

output enable.

5. Select (Input Signals) as shown in figure and assign pin number for the

input corresponding to axis.

Fig.4.6 output signals configuration

Fig.4.7 input signals configuration

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6. To configure the operating keys used in manual testing open (Config) –

(System Hotkeys) as shown in Fig.4.8

7. The following screen will appear then adjust the keys

Fig.4.8 keys configuration

Fig.4.9 System hot keys setup

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8. Adjusting motor tuning

4.2.1.4 Determined Steps per Unit Length

a) Calculation Method

Stepper motor specifications:

Model SANYO DENKI

1.8 deg. per step

3.4 V

2 A

No. of steps per 1 rev = 200 steps/rev.

For X,Y and Z-axis

Power screw Pitch = 4 mm

From above No. of steps per 1 rev = 200 steps/rev.

Then the No. of steps per mm = 200/4 = 50 steps/mm.

Fig.4.10 motor tuning configuration

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b) Calibration Method

Open setting tap and press on (set steps per unit), the dialog box will

appear select the axis which need calibrate

Enter the required moved distance

Fig.4.11 calibration window

Fig.4.12 distance box

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After the motor stop enter the measured distance

4.2.2 Power Supply

The power converter usually refered to as the “power supply unit (PSU)” is

often used to change the form from supplied power from alternating current

(AC) from the power grid. To direct current (DC) that is more easily used by

the machines drive motor

4.2.3 Breakout Board Or Interface

This board is really only a gateway that allows the computer to send and

receive signals to the drivers and limit switches. There isn’t much to it aside

from a connector for the straight‐through parallel port cable and some

connections for the wires coming from each of the driver boards and limit

switches. Shown as Fig.4.14

Fig.4.13 measured value box

Fig.4.14 interface board

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This board is a simple, cheap, buffered no isolated parallel breakout board. It

supports four output control signal groups to drive four axis CNC machine.

Each signal group supports three control signals ( Enable , Direction and

Clock ) . Two output relays could be enabled via DIP switch for additional

spindle control. The interface also supports five dry contact inputs for travel

limit switches.

4.2.3.1 Interface Features

1. Four output control signal groups. labeled X-axis, Y-axis, Z-axis, V-

Axis.

2. Ena , Dir , Clk control signals are available. For pin assignment and

address show table 4.1.

3. Two output relays 5V coil / 10A contacts (resistive load).

4. Normally open and normally closed contacts are available..

5. Five external inputs (dry contact).

4.2.3.2 Parallel Port

It link between computer and interface, which the signal path through it

Shown as Fig.4.15

Fig.4.15 parallel port

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4.2.3.3 Input And Output Ports

4.2.4 Motors Driver

There are many driver circuits can use to drive stepper ,according to the

motor type the drive circuit is create according to it is required voltage and

current .

4.2.4.1 Type of Common Driver Circuits,

1 uln2003 driver

2 transistorized driver

3 micro driver

4 H-bridge and l297 circuit

Table 4.1 input and outputs Pins

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Using H-bridge and l297 circuit

It is the last driver that has been made and the simplest one because it solve

the problems of above circuits, it solve the problem of the need to a

programmer to create the program in micro controller chip by using l297

chip and it don’t need program. And it solve the problem of the transistor

connection and installation by using l298 chip which the is have transistors

inside and it is easy to connect it .

4.2.4.2 Advantages of H-bridge and l297 circuit

1 Easy to build

2 More reliable

3 Its component is available and cheap

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4.2.4.3 Driver Circuit

Fig.4.16 driver circuit (H-Bridge)

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4.2.4.4 Driver PCB

4.2.4.5 Driver Picture

Fig.4.17 printed circuit

board

a) Top copper b) Bottom copper

Fig.4.18 driver

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4.2.4.6 Machine Circuits Box

Fig.4.19 machine circuits box

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4.2.5 Motors

It a device which convert electric power into mechanical power which provide

required torque

Fig.4.20 driver axis

Fig.4.21 stepper motor

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4.2.5.1 Motors Type

There are two types of motors that are typically used in CNC machinery:

stepper and servo. Each of these motor types get both their power and

direction/ rotation information from a drive or amplifier. If you have spent any

amount of time looking into the contrast of using a stepper as compared to a

servo motor, you will find that there are distinct differences between the two.

The basic operation of each type of these motors will be presented here for

you to make your own determination regarding which type of motor would

most benefit your system. After a discussion on each motor type, a contrast

comparison of the two is presented. Hybrid configurations are also possible

with the addition of an encoder to a stepper motor.

Fig.4.22 illustrates some basic differences in stepper

and DC motor rotation.

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4.2.5.2 Open Loop (Stepper) Versus Closed Loop (Servo) Commutation

a) Open Loop

Open loop refers to a system where communication between the control

system and the motor is one way (no feedback) as shown in Fig.4.1

Open loop system use stepper motor, which the stepper motor doesn’t

required feedback hardware, the price for an open loop CNC system is

much cheaper and simpler than closed loop, which the servo motor cannot

use in open loop system

b) Closed Loop

The closed loop system has a feedback system (encoder) to monitor the

output of the motors.as shown in Fig.4.24

Closed systems are able to correct errors in position, velocity, and

acceleration

Fig.4.23 open loop

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The stepper motor used in our machine is [unipolar motor converted to half

coil (High Torque) bipolar stepper]. As illustrated in Fig.

4.2.5.3 Stepper Motors Advantages and Disadvantages

Stepper motors have several advantages:

a) They can be operated in open loop systems

b) Position error is that of a single step.

c) Error is non‐cumulative between steps

d) Discrete pulses control motor position

Stepper Motors Disadvantages are:

a) Fixed increments of motion.

b) Low efficiency, driver choice important.

c) High oscillation and overshoot to a step input.

Fig.4.24 closed loop

Fig.4.25 unipolar motor as bipolar

MINI CNC MACHINE (3-AXIS) CH.4

110

d) Limited power output.

e) Limited ability to handle large inertial loads.

f) Friction errors can increase position error.

4.2.6 Switches

Most machines use limit switches or proximity switches at the limits

of travel to prevent the machine from driving itself beyond its own

physical limits. Literally, the machine could drive itself off the end of

the linear motion system and fall on the floor if you (accidentally) tell

it to do so and there are no mechanical stops. So by adding limit

switching to all axes of the machine it is give more safety and if

anything happened it send signals to interface then from interface to

mach3 to tell that there are errors happened. Another switches that use

it is emergency stop which is provide an immediately stop when press

in it.

CHAPTER (5)

EXPERIMENTAL

WORK AND

VERIFICATION

MINI CNC MACHINE (3-AXIS) CH.5

111

Fig.6.1 Raw material

CHAPTER 5

EXPERIMENTAL WORK AND VERIFICATION

5.1. MACHINING PARTS

Mini CNC machine has Machined three samples each sample

100 mm *100 mm two sample of wood (MDF) and one sample from

aluminum to testing the machine and calculate error percentage

5.1.1. First Sample (Mdf)

5.1.1.1. Raw Material

5.1.1.2. Detail Drawing For Machined Part

Fig.6.2 Part Drawing

MINI CNC MACHINE (3-AXIS) CH.5

112

Fig.6.3 Sample 1

5.1.1.3. Machined Part

5.1.1.4. G-Codes For First Sample

(WinCAM by EMCO [c] 95-96, NC-program FANUC Series 0M )

N0005 G54

N0010 G97 G94

N0015 G52 X0. Y0. Z0.

N0020 F300

N0025 S1000

N0030 G49

MINI CNC MACHINE (3-AXIS) CH.5

113

N0035 T3 H5 G43 M6 (* Slot mill cutter 4mm *)

N0040 M3

(**#00002 Contour milling, ISO format **)

N0045 G94 F200 G97 S1000

N0050 G0 Z0.

N0055 G1 Z-0.5 F200

N0060 G1 G42 H6 X24.755 Y47.086 F300

N0065 G3 X26.23 Y45.332 I5.245 J2.914

N0070 G2 X29.892 Y36.493 I-6.283 J-7.78

N0075 G3 X36.493 Y29.892 I5.966 J-0.635

N0080 G2 X45.332 Y26.23 I1.059 J-9.944

N0085 G3 X54.668 Y26.23 I4.668 J3.77

N0090 G2 X63.507 Y29.892 I7.78 J-6.283

N0095 G3 X70.108 Y36.493 I0.635 J5.966

N0100 G2 X73.77 Y45.332 I9.944 J1.059

N0105 G3 X73.77 Y54.668 I-3.77 J4.668

N0110 G2 X70.108 Y63.507 I6.283 J7.78

N0115 G3 X63.507 Y70.108 I-5.966 J0.635

N0120 G2 X54.668 Y73.77 I-1.059 J9.944

N0125 G3 X45.332 Y73.77 I-4.668 J-3.77

N0130 G2 X36.493 Y70.108 I-7.78 J6.283

N0135 G3 X29.892 Y63.507 I-0.635 J-5.966

MINI CNC MACHINE (3-AXIS) CH.5

114

N0140 G2 X26.23 Y54.668 I-9.944 J-1.059

N0145 G3 X24.755 Y47.086 I3.77 J-4.668

N0150 G1 G40 X-60. Y0.

N0155 G1 Z-1. F200

N0160 G1 G42 H6 X24.755 Y47.086 F300

N0165 G3 X26.23 Y45.332 I5.245 J2.914

N0170 G2 X29.892 Y36.493 I-6.283 J-7.78

N0175 G3 X36.493 Y29.892 I5.966 J-0.635

N0180 G2 X45.332 Y26.23 I1.059 J-9.944

N0185 G3 X54.668 Y26.23 I4.668 J3.77

N0190 G2 X63.507 Y29.892 I7.78 J-6.283

N0195 G3 X70.108 Y36.493 I0.635 J5.966

N0200 G2 X73.77 Y45.332 I9.944 J1.059

N0205 G3 X73.77 Y54.668 I-3.77 J4.668

N0210 G2 X70.108 Y63.507 I6.283 J7.78

N0215 G3 X63.507 Y70.108 I-5.966 J0.635

N0220 G2 X54.668 Y73.77 I-1.059 J9.944

N0225 G3 X45.332 Y73.77 I-4.668 J-3.77

N0230 G2 X36.493 Y70.108 I-7.78 J6.283

N0235 G3 X29.892 Y63.507 I-0.635 J-5.966

N0240 G2 X26.23 Y54.668 I-9.944 J-1.059

N0245 G3 X24.755 Y47.086 I3.77 J-4.668

MINI CNC MACHINE (3-AXIS) CH.5

115

N0250 G1 G40 X-60. Y0.

N0255 G1 Z-1.5 F200

N0260 G1 G42 H6 X24.755 Y47.086 F300

N0265 G3 X26.23 Y45.332 I5.245 J2.914

N0270 G2 X29.892 Y36.493 I-6.283 J-7.78

N0275 G3 X36.493 Y29.892 I5.966 J-0.635

N0280 G2 X45.332 Y26.23 I1.059 J-9.944

N0285 G3 X54.668 Y26.23 I4.668 J3.77

N0290 G2 X63.507 Y29.892 I7.78 J-6.283

N0295 G3 X70.108 Y36.493 I0.635 J5.966

N0300 G2 X73.77 Y45.332 I9.944 J1.059

N0305 G3 X73.77 Y54.668 I-3.77 J4.668

N0310 G2 X70.108 Y63.507 I6.283 J7.78

N0315 G3 X63.507 Y70.108 I-5.966 J0.635

N0320 G2 X54.668 Y73.77 I-1.059 J9.944

N0325 G3 X45.332 Y73.77 I-4.668 J-3.77

N0330 G2 X36.493 Y70.108 I-7.78 J6.283

N0335 G3 X29.892 Y63.507 I-0.635 J-5.966

N0340 G2 X26.23 Y54.668 I-9.944 J-1.059

N0345 G3 X24.755 Y47.086 I3.77 J-4.668

N0350 G1 G40 X-60. Y0.

N0355 G1 Z-2. F200

MINI CNC MACHINE (3-AXIS) CH.5

116

N0360 G1 G42 H6 X24.755 Y47.086 F300

N0365 G3 X26.23 Y45.332 I5.245 J2.914

N0370 G2 X29.892 Y36.493 I-6.283 J-7.78

N0375 G3 X36.493 Y29.892 I5.966 J-0.635

N0380 G2 X45.332 Y26.23 I1.059 J-9.944

N0385 G3 X54.668 Y26.23 I4.668 J3.77

N0390 G2 X63.507 Y29.892 I7.78 J-6.283

N0395 G3 X70.108 Y36.493 I0.635 J5.966

N0400 G2 X73.77 Y45.332 I9.944 J1.059

N0405 G3 X73.77 Y54.668 I-3.77 J4.668

N0410 G2 X70.108 Y63.507 I6.283 J7.78

N0415 G3 X63.507 Y70.108 I-5.966 J0.635

N0420 G2 X54.668 Y73.77 I-1.059 J9.944

N0425 G3 X45.332 Y73.77 I-4.668 J-3.77

N0430 G2 X36.493 Y70.108 I-7.78 J6.283

N0435 G3 X29.892 Y63.507 I-0.635 J-5.966

N0440 G2 X26.23 Y54.668 I-9.944 J-1.059

N0445 G3 X24.755 Y47.086 I3.77 J-4.668

N0450 G1 G40 X-60. Y0.

N0455 G1 Z-2.5 F200

N0460 G1 G42 H6 X24.755 Y47.086 F300

N0465 G3 X26.23 Y45.332 I5.245 J2.914

MINI CNC MACHINE (3-AXIS) CH.5

117

N0470 G2 X29.892 Y36.493 I-6.283 J-7.78

N0475 G3 X36.493 Y29.892 I5.966 J-0.635

N0480 G2 X45.332 Y26.23 I1.059 J-9.944

N0485 G3 X54.668 Y26.23 I4.668 J3.77

N0490 G2 X63.507 Y29.892 I7.78 J-6.283

N0495 G3 X70.108 Y36.493 I0.635 J5.966

N0500 G2 X73.77 Y45.332 I9.944 J1.059

N0505 G3 X73.77 Y54.668 I-3.77 J4.668

N0510 G2 X70.108 Y63.507 I6.283 J7.78

N0515 G3 X63.507 Y70.108 I-5.966 J0.635

N0520 G2 X54.668 Y73.77 I-1.059 J9.944

N0525 G3 X45.332 Y73.77 I-4.668 J-3.77

N0530 G2 X36.493 Y70.108 I-7.78 J6.283

N0535 G3 X29.892 Y63.507 I-0.635 J-5.966

N0540 G2 X26.23 Y54.668 I-9.944 J-1.059

N0545 G3 X24.755 Y47.086 I3.77 J-4.668

N0550 G1 G40 X-60. Y0.

N0555 G1 Z-3. F200

N0560 G1 G42 H6 X24.755 Y47.086 F300

N0565 G3 X26.23 Y45.332 I5.245 J2.914

N0570 G2 X29.892 Y36.493 I-6.283 J-7.78

N0575 G3 X36.493 Y29.892 I5.966 J-0.635

MINI CNC MACHINE (3-AXIS) CH.5

118

N0580 G2 X45.332 Y26.23 I1.059 J-9.944

N0585 G3 X54.668 Y26.23 I4.668 J3.77

N0590 G2 X63.507 Y29.892 I7.78 J-6.283

N0595 G3 X70.108 Y36.493 I0.635 J5.966

N0600 G2 X73.77 Y45.332 I9.944 J1.059

N0605 G3 X73.77 Y54.668 I-3.77 J4.668

N0610 G2 X70.108 Y63.507 I6.283 J7.78

N0615 G3 X63.507 Y70.108 I-5.966 J0.635

N0620 G2 X54.668 Y73.77 I-1.059 J9.944

N0625 G3 X45.332 Y73.77 I-4.668 J-3.77

N0630 G2 X36.493 Y70.108 I-7.78 J6.283

N0635 G3 X29.892 Y63.507 I-0.635 J-5.966

N0640 G2 X26.23 Y54.668 I-9.944 J-1.059

N0645 G3 X24.755 Y47.086 I3.77 J-4.668

N0650 G1 G40 X-60. Y0.

N0655 G0 Z2.

(**#00002 end **)

N0660 G0 Z30.

N0665 M5

N0670 M30

MINI CNC MACHINE (3-AXIS) CH.5

119

Fig.6.4 Drawing

Fig.6.5 Sample 2

5.1.2. The Second Sample (MDF)

Work piece Dimension 100*100

Depth of contour = 3 [mm]

5.1.2.1. Detail Drawing For Machined Part

5.1.2.3. Machined Part

MINI CNC MACHINE (3-AXIS) CH.5

120

5.1.2.4. G-Codes For Machined Part

(* WinCAM by EMCO [c] 95-96, NC-program FANUC Series 0M *)

N0005 G54

N0010 G97 G94

N0015 G52 X0. Y0. Z0.

N0020 F100

N0025 S1000

N0030 F300

N0035 G49

N0040 T2 H3 G43 M6 (* Slot mill cutter 5mm *)

N0045 G0 Z3.

N0050 G0 X1.564 Y2.356

N0055 M3

N0060 G49

N0065 T2 H3 G43 M6 (* Slot mill cutter 5mm *)

(**#00002 Contour milling, ISO format **)

N0070 G94 F300 G97 S1000

N0075 G0 Z1.

N0080 G1 Z0. F300

N0085 G1 G42 H4 X5. Y5. F300

N0090 G1 X55. Y5.

MINI CNC MACHINE (3-AXIS) CH.5

121

N0095 G2 X65. Y15. I10. J0.

N0100 G1 X65. Y55.

N0105 G1 X55. Y65.

N0110 G1 X15. Y65.

N0115 G3 X5. Y55. I0. J-10.

N0120 G1 X5. Y5.

N0125 G1 G40 X1.564 Y2.356

N0130 G1 Z-1. F300

N0135 G1 G42 H4 X5. Y5. F300

N0140 G1 X55. Y5.

N0145 G2 X65. Y15. I10. J0.

N0150 G1 X65. Y55.

N0155 G1 X55. Y65.

N0160 G1 X15. Y65.

N0165 G3 X5. Y55. I0. J-10.

N0170 G1 X5. Y5.

N0175 G1 G40 X1.564 Y2.356

N0180 G1 Z-2. F300

N0185 G1 G42 H4 X5. Y5. F300

N0190 G1 X55. Y5.

N0195 G2 X65. Y15. I10. J0.

N0200 G1 X65. Y55.

MINI CNC MACHINE (3-AXIS) CH.5

122

N0205 G1 X55. Y65.

N0210 G1 X15. Y65.

N0215 G3 X5. Y55. I0. J-10.

N0220 G1 X5. Y5.

N0225 G1 G40 X1.564 Y2.356

N0230 G1 Z-3. F300

N0235 G1 G42 H4 X5. Y5. F300

N0240 G1 X55. Y5.

N0245 G2 X65. Y15. I10. J0.

N0250 G1 X65. Y55.

N0255 G1 X55. Y65.

N0260 G1 X15. Y65.

N0265 G3 X5. Y55. I0. J-10.

N0270 G1 X5. Y5.

N0275 G1 G40 X1.564 Y2.356

N0280 G1 Z-4. F300

N0285 G1 G42 H4 X5. Y5. F300

N0290 G1 X55. Y5.

N0295 G2 X65. Y15. I10. J0.

N0300 G1 X65. Y55.

N0305 G1 X55. Y65.

N0310 G1 X15. Y65.

MINI CNC MACHINE (3-AXIS) CH.5

123

N0315 G3 X5. Y55. I0. J-10.

N0320 G1 X5. Y5.

N0325 G1 G40 X1.564 Y2.356

N0330 G1 Z-5. F300

N0335 G1 G42 H4 X5. Y5. F300

N0340 G1 X55. Y5.

N0345 G2 X65. Y15. I10. J0.

N0350 G1 X65. Y55.

N0355 G1 X55. Y65.

N0360 G1 X15. Y65.

N0365 G3 X5. Y55. I0. J-10.

N0370 G1 X5. Y5.

N0375 G1 G40 X1.564 Y2.356

N0380 G0 Z2.

(**#00002 end **)

(**#00004 rectangular pocket, ISO format **)

N0385 G94 F300 G97 S1000

N0390 G0 X40. Y35. M3

N0395 G1 Z1.

N0400 G1 X30. Y35.

N0405 G1 Z0. F300

MINI CNC MACHINE (3-AXIS) CH.5

124

N0410 X50. Y35. F300

N0415 G1 X50. Y32.5

N0420 X27.5 Y32.5

N0425 X27.5 Y37.5

N0430 X52.5 Y37.5

N0435 X52.5 Y32.5

N0440 G1 X52.5 Y30.

N0445 X25. Y30.

N0450 X25. Y40.

N0455 X55. Y40.

N0460 X55. Y30.

N0465 G1 Y27.5 X55.

N0470 G1 X25. Y27.5

N0475 G2 X22.5 Y30. I0. J2.5

N0480 G1 X22.5 Y40.

N0485 G2 X25. Y42.5 I2.5 J0.

N0490 G1 X55. Y42.5

N0495 G2 X57.5 Y40. I0. J-2.5

N0500 G1 X57.5 Y30.

N0505 G2 X55. Y27.5 I-2.5 J0.

N0510 G1 X40. Y27.5

N0515 G2 X40. Y35. I0. J3.75

MINI CNC MACHINE (3-AXIS) CH.5

125

N0520 G1 X30. Y35.

N0525 G1 Z-1. F300

N0530 X50. Y35. F300

N0535 G1 X50. Y32.5

N0540 X27.5 Y32.5

N0545 X27.5 Y37.5

N0550 X52.5 Y37.5

N0555 X52.5 Y32.5

N0560 G1 X52.5 Y30.

N0565 X25. Y30.

N0570 X25. Y40.

N0575 X55. Y40.

N0580 X55. Y30.

N0585 G1 Y27.5 X55.

N0590 G1 X25. Y27.5

N0595 G2 X22.5 Y30. I0. J2.5

N0600 G1 X22.5 Y40.

N0605 G2 X25. Y42.5 I2.5 J0.

N0610 G1 X55. Y42.5

N0615 G2 X57.5 Y40. I0. J-2.5

N0620 G1 X57.5 Y30.

N0625 G2 X55. Y27.5 I-2.5 J0.

MINI CNC MACHINE (3-AXIS) CH.5

126

N0630 G1 X40. Y27.5

N0635 G2 X40. Y35. I0. J3.75

N0640 G1 X30. Y35.

N0645 G1 Z-2. F300

N0650 X50. Y35. F300

N0655 G1 X50. Y32.5

N0660 X27.5 Y32.5

N0665 X27.5 Y37.5

N0670 X52.5 Y37.5

N0675 X52.5 Y32.5

N0680 G1 X52.5 Y30.

N0685 X25. Y30.

N0690 X25. Y40.

N0695 X55. Y40.

N0700 X55. Y30.

N0705 G1 Y27.5 X55.

N0710 G1 X25. Y27.5

N0715 G2 X22.5 Y30. I0. J2.5

N0720 G1 X22.5 Y40.

N0725 G2 X25. Y42.5 I2.5 J0.

N0730 G1 X55. Y42.5

N0735 G2 X57.5 Y40. I0. J-2.5

MINI CNC MACHINE (3-AXIS) CH.5

127

N0740 G1 X57.5 Y30.

N0745 G2 X55. Y27.5 I-2.5 J0.

N0750 G1 X40. Y27.5

N0755 G2 X40. Y35. I0. J3.75

N0760 G1 X30. Y35.

N0765 G1 Z-3. F300

N0770 X50. Y35. F300

N0775 G1 X50. Y32.5

N0780 X27.5 Y32.5

N0785 X27.5 Y37.5

N0790 X52.5 Y37.5

N0795 X52.5 Y32.5

N0800 G1 X52.5 Y30.

N0805 X25. Y30.

N0810 X25. Y40.

N0815 X55. Y40.

N0820 X55. Y30.

N0825 G1 Y27.5 X55.

N0830 G1 X25. Y27.5

N0835 G2 X22.5 Y30. I0. J2.5

N0840 G1 X22.5 Y40.

N0845 G2 X25. Y42.5 I2.5 J0.

MINI CNC MACHINE (3-AXIS) CH.5

128

N0850 G1 X55. Y42.5

N0855 G2 X57.5 Y40. I0. J-2.5

N0860 G1 X57.5 Y30.

N0865 G2 X55. Y27.5 I-2.5 J0.

N0870 G1 X40. Y27.5

N0875 G2 X40. Y35. I0. J3.75

N0880 G1 X30. Y35.

N0885 G1 Z-4. F300

N0890 X50. Y35. F300

N0895 G1 X50. Y32.5

N0900 X27.5 Y32.5

N0905 X27.5 Y37.5

N0910 X52.5 Y37.5

N0915 X52.5 Y32.5

N0920 G1 X52.5 Y30.

N0925 X25. Y30.

N0930 X25. Y40.

N0935 X55. Y40.

N0940 X55. Y30.

N0945 G1 Y27.5 X55.

N0950 G1 X25. Y27.5

N0955 G2 X22.5 Y30. I0. J2.5

MINI CNC MACHINE (3-AXIS) CH.5

129

N0960 G1 X22.5 Y40.

N0965 G2 X25. Y42.5 I2.5 J0.

N0970 G1 X55. Y42.5

N0975 G2 X57.5 Y40. I0. J-2.5

N0980 G1 X57.5 Y30.

N0985 G2 X55. Y27.5 I-2.5 J0.

N0990 G1 X40. Y27.5

N0995 G2 X40. Y35. I0. J3.75

N1000 G1 X30. Y35.

N1005 G1 Z-5. F300

N1010 X50. Y35. F300

N1015 G1 X50. Y32.5

N1020 X27.5 Y32.5

N1025 X27.5 Y37.5

N1030 X52.5 Y37.5

N1035 X52.5 Y32.5

N1040 G1 X52.5 Y30.

N1045 X25. Y30.

N1050 X25. Y40.

N1055 X55. Y40.

N1060 X55. Y30.

N1065 G1 Y27.5 X55.

MINI CNC MACHINE (3-AXIS) CH.5

130

N1070 G1 X25. Y27.5

N1075 G2 X22.5 Y30. I0. J2.5

N1080 G1 X22.5 Y40.

N1085 G2 X25. Y42.5 I2.5 J0.

N1090 G1 X55. Y42.5

N1095 G2 X57.5 Y40. I0. J-2.5

N1100 G1 X57.5 Y30.

N1105 G2 X55. Y27.5 I-2.5 J0.

N1110 G1 X40. Y27.5

N1115 G2 X40. Y35. I0. J3.75

N1120 G0 X40. Y35. Z3.

(**#00004 end **)

(**#00031 Drilling cycle – chip cutting, FANUC 0M **)

N1125 G94 F300 G97 S1000

N1130 G0 Z1.

N1135 G73 X35. Y55. Z-7. R1. Q1.

N1140 G0 Z2.

N1145 G0 X20. Y55.

N1150 G0 Z1.

N1155 G73 X20. Y55. Z-7. R1. Q1.

N1160 G0 Z2.

MINI CNC MACHINE (3-AXIS) CH.5

131

N1165 G0 X50. Y55.

N1170 G0 Z1.

N1175 G73 X50. Y55. Z-7. R1. Q1.

N1180 G0 Z2.

N1185 G80

(**#00031 end **)

N1190 G0 Z3.

X16 Y16

G01 Z-1 F300

G3 Y16 X17 R0.5 F300

Y16 X15 R1

Y16 X18 R1.5

Y16 X14 R2

Y16 X19 R2.5

Y16 X13 R3

Y16 X20 R3.5

Y16 X12 R4

Y16 X20.5 R4.25

Y16 X11.5 R4.5

X20.5 Y16 R4.5

Y16.375 X20.125 R0.375

G00 Z2

MINI CNC MACHINE (3-AXIS) CH.5

132

X16 Y16

G01 Z-2 F300

G3 Y16 X17 R0.5 F300

Y16 X15 R1

Y16 X18 R1.5

Y16 X14 R2

Y16 X19 R2.5

Y16 X13 R3

Y16 X20 R3.5

Y16 X12 R4

Y16 X20.5 R4.25

Y16 X11.5 R4.5

X20.5 Y16 R4.5

Y16.375 X20.125 R0.375

G00 Z2

X16 Y16

G01 Z-3 F300

G3 Y16 X17 R0.5 F300

Y16 X15 R1

Y16 X18 R1.5

Y16 X14 R2

Y16 X19 R2.5

MINI CNC MACHINE (3-AXIS) CH.5

133

Y16 X13 R3

Y16 X20 R3.5

Y16 X12 R4

Y16 X20.5 R4.25

Y16 X11.5 R4.5

X20.5 Y16 R4.5

Y16.375 X20.125 R0.375

G00 Z2

X16 Y16

G01 Z-4 F300

G3 Y16 X17 R0.5 F300

Y16 X15 R1

Y16 X18 R1.5

Y16 X14 R2

Y16 X19 R2.5

Y16 X13 R3

Y16 X20 R3.5

Y16 X12 R4

Y16 X20.5 R4.25

Y16 X11.5 R4.5

X20.5 Y16 R4.5

Y16.375 X20.125 R0.375

MINI CNC MACHINE (3-AXIS) CH.5

134

G00 Z2

X16 Y16

G01 Z-5 F300

G3 Y16 X17 R0.5 F300

Y16 X15 R1

Y16 X18 R1.5

Y16 X14 R2

Y16 X19 R2.5

Y16 X13 R3

Y16 X20 R3.5

Y16 X12 R4

Y16 X20.5 R4.25

Y16 X11.5 R4.5

X20.5 Y16 R4.5

Y16.375 X20.125 R0.375

G00 Z30

M5 M9

M30

MINI CNC MACHINE (3-AXIS) CH.5

135

Fig.6.7 Sample 3

Fig.6.8 Drawing

5.1.3. The Third Sample (From Aluminum)

5.1.3.1. Raw Material

5.1.3.2. Detail Drawing For Machined Part

MINI CNC MACHINE (3-AXIS) CH.5

136

Fig.6.9 Sample 3

5.1.3.3. Machined Part

5.1.3.4. G-Codes For Machined Part

(* WinCAM by EMCO [c] 95-96, NC-program FANUC Series 0M *)

N0005 G54

N0010 G97 G94

N0015 G52 X0. Y0. Z0.

N0020 F200

N0025 S1000

N0030 G49

N0035 G49

MINI CNC MACHINE (3-AXIS) CH.5

137

N0040 T2 H3 G43 M6 (* Slot mill cutter 5mm *)

N0045 M3

N0050 G49

N0055 T2 H3 G43 M6 (* Slot mill cutter 5mm *)

N0060 G0 X-1.151 Y-2.151

N0065 G0 Z3.

(**#00002 Contour milling, ISO format **)

N0070 G94 F200 G97 S1000

N0075 G0 Z1.

N0080 G1 Z0.5 F200

N0085 G1 G42 H4 X2.494 Y1.915 F200

N0090 G3 X10. Y0.429 I5.006 J5.585

N0095 G2 X50. Y0.429 I20. J-56.569

N0100 G3 X59.571 Y10. I2.5 J7.071

N0105 G2 X59.571 Y50. I56.569 J20.

N0110 G3 X50. Y59.571 I-7.071 J2.5

N0115 G2 X10. Y59.571 I-20. J56.569

N0120 G3 X0.429 Y50. I-2.5 J-7.071

N0125 G2 X0.429 Y10. I-56.569 J-20.

N0130 G3 X2.494 Y1.915 I7.071 J-2.5

N0135 G1 G40 X-1.151 Y-2.151

MINI CNC MACHINE (3-AXIS) CH.5

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N0140 G1 Z0. F200

N0145 G1 G42 H4 X2.494 Y1.915 F200

N0150 G3 X10. Y0.429 I5.006 J5.585

N0155 G2 X50. Y0.429 I20. J-56.569

N0160 G3 X59.571 Y10. I2.5 J7.071

N0165 G2 X59.571 Y50. I56.569 J20.

N0170 G3 X50. Y59.571 I-7.071 J2.5

N0175 G2 X10. Y59.571 I-20. J56.569

N0180 G3 X0.429 Y50. I-2.5 J-7.071

N0185 G2 X0.429 Y10. I-56.569 J-20.

N0190 G3 X2.494 Y1.915 I7.071 J-2.5

N0195 G1 G40 X-1.151 Y-2.151

N0200 G1 Z-0.5 F200

N0205 G1 G42 H4 X2.494 Y1.915 F200

N0210 G3 X10. Y0.429 I5.006 J5.585

N0215 G2 X50. Y0.429 I20. J-56.569

N0220 G3 X59.571 Y10. I2.5 J7.071

N0225 G2 X59.571 Y50. I56.569 J20.

N0230 G3 X50. Y59.571 I-7.071 J2.5

N0235 G2 X10. Y59.571 I-20. J56.569

N0240 G3 X0.429 Y50. I-2.5 J-7.071

N0245 G2 X0.429 Y10. I-56.569 J-20.

MINI CNC MACHINE (3-AXIS) CH.5

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N0250 G3 X2.494 Y1.915 I7.071 J-2.5

N0255 G1 G40 X-1.151 Y-2.151

N0260 G1 Z-1. F200

N0265 G1 G42 H4 X2.494 Y1.915 F200

N0270 G3 X10. Y0.429 I5.006 J5.585

N0275 G2 X50. Y0.429 I20. J-56.569

N0280 G3 X59.571 Y10. I2.5 J7.071

N0285 G2 X59.571 Y50. I56.569 J20.

N0290 G3 X50. Y59.571 I-7.071 J2.5

N0295 G2 X10. Y59.571 I-20. J56.569

N0300 G3 X0.429 Y50. I-2.5 J-7.071

N0305 G2 X0.429 Y10. I-56.569 J-20.

N0310 G3 X2.494 Y1.915 I7.071 J-2.5

N0315 G1 G40 X-1.151 Y-2.151

N0320 G1 Z-1.5 F200

N0325 G1 G42 H4 X2.494 Y1.915 F200

N0330 G3 X10. Y0.429 I5.006 J5.585

N0335 G2 X50. Y0.429 I20. J-56.569

N0340 G3 X59.571 Y10. I2.5 J7.071

N0345 G2 X59.571 Y50. I56.569 J20.

N0350 G3 X50. Y59.571 I-7.071 J2.5

N0355 G2 X10. Y59.571 I-20. J56.569

MINI CNC MACHINE (3-AXIS) CH.5

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N0360 G3 X0.429 Y50. I-2.5 J-7.071

N0365 G2 X0.429 Y10. I-56.569 J-20.

N0370 G3 X2.494 Y1.915 I7.071 J-2.5

N0375 G1 G40 X-1.151 Y-2.151

N0380 G1 Z-2. F200

N0385 G1 G42 H4 X2.494 Y1.915 F200

N0390 G3 X10. Y0.429 I5.006 J5.585

N0395 G2 X50. Y0.429 I20. J-56.569

N0400 G3 X59.571 Y10. I2.5 J7.071

N0405 G2 X59.571 Y50. I56.569 J20.

N0410 G3 X50. Y59.571 I-7.071 J2.5

N0415 G2 X10. Y59.571 I-20. J56.569

N0420 G3 X0.429 Y50. I-2.5 J-7.071

N0425 G2 X0.429 Y10. I-56.569 J-20.

N0430 G3 X2.494 Y1.915 I7.071 J-2.5

N0435 G1 G40 X-1.151 Y-2.151

N0440 G1 Z-2.5 F200

N0445 G1 G42 H4 X2.494 Y1.915 F200

N0450 G3 X10. Y0.429 I5.006 J5.585

N0455 G2 X50. Y0.429 I20. J-56.569

N0460 G3 X59.571 Y10. I2.5 J7.071

N0465 G2 X59.571 Y50. I56.569 J20.

MINI CNC MACHINE (3-AXIS) CH.5

141

N0470 G3 X50. Y59.571 I-7.071 J2.5

N0475 G2 X10. Y59.571 I-20. J56.569

N0480 G3 X0.429 Y50. I-2.5 J-7.071

N0485 G2 X0.429 Y10. I-56.569 J-20.

N0490 G3 X2.494 Y1.915 I7.071 J-2.5

N0495 G1 G40 X-1.151 Y-2.151

N0500 G1 Z-3. F200

N0505 G1 G42 H4 X2.494 Y1.915 F200

N0510 G3 X10. Y0.429 I5.006 J5.585

N0515 G2 X50. Y0.429 I20. J-56.569

N0520 G3 X59.571 Y10. I2.5 J7.071

N0525 G2 X59.571 Y50. I56.569 J20.

N0530 G3 X50. Y59.571 I-7.071 J2.5

N0535 G2 X10. Y59.571 I-20. J56.569

N0540 G3 X0.429 Y50. I-2.5 J-7.071

N0545 G2 X0.429 Y10. I-56.569 J-20.

N0550 G3 X2.494 Y1.915 I7.071 J-2.5

N0555 G1 G40 X-1.151 Y-2.151

N0560 G0 Z2.

(**#00002 end **)

(**#00031 Drilling cycle - chip cutting, FANUC 0M **)

MINI CNC MACHINE (3-AXIS) CH.5

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N0565 G94 F200 G97 S1000

N0570 G0 Z1.

N0575 G73 X7.5 Y7.5 Z-5. R1. Q0.5

N0580 G0 Z2.

N0585 G0 X52.5 Y7.5

N0590 G0 Z1.

N0595 G73 X52.5 Y7.5 Z-5. R1. Q0.5

N0600 G0 Z2.

N0605 G0 X52.5 Y52.5

N0610 G0 Z1.

N0615 G73 X52.5 Y52.5 Z-5. R1. Q0.5

N0620 G0 Z2.

N0625 G0 X7.5 Y52.5

N0630 G0 Z1.

N0635 G73 X7.5 Y52.5 Z-5. R1. Q0.5

N0640 G0 Z30.

N0645 G80

m5

(**#00031 end **)

N0650 M30

MINI CNC MACHINE (3-AXIS) CH.5

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5.2. CONCLUSION

Errors in Machining

When compared dimension in detail drawing with product dimension

found that

Maximum error in this part = 0.44 mm

Reasons

1. There is no encoder, which it provide the system with feedback to

minimize the positional error.

2. Stepper motor are used purchased.

3. Calibration done manually (Calculations of steps per unit see P.91.

CHAPTER (6)

FUTURE WORK

MINI CNC MACHINE (3-AXIS) CH.6

144

CHAPTER 6 FUTURE WORK

During working in the project we were not able to solve all the problems

which we have faced in a satisfactory manner. Such problems were related

with money or advanced technologies. Such problems may be over come in

some future work. Sample of these problems with some future work for

development in machine Are:

Adding fourth axis (A-axis) which can make machine able to make

variety of parts.

Adding encoder

When an encoder is used with a stepper motor it is commonly

referred to as a hybrid configuration. Encoders are devices that

optically, magnetically electronically monitor and provide feedback as

to the actual position of each system axis in near real time.

Replace the present power screws (Acme thread) with ball screws

which reduce the friction, reduce the load on the stepper motor and

torque needed.

Replace the present router with controlled spindle which have two

directions (clock wise and counter clock wise) and have variety of

speed.

MINI CNC MACHINE (3-AXIS)

127

References

1. Koren, J. (1983) Computer Control of Manufacturing Systems, 1st

Edition, McGraw-Hill, Tokyo, 40(2):603–614.

2. McMahon, C. and Browne, J. (1998) CADCAM—Principles,

Practice and Manufacturing Management, 2nd

Edition, Addison-

Wesley, Reading, MA, 47(2):525–540

3. Diamond, W.J. (2001). Practical experiment design for engineers

and scientists. Third edition. John Wiley & Sons. New York.

4. MCP2551 High-Speed CAN Transceiver Data Sheet (2003).

Microchip Technology, Document No.DS21667D.

5. http://tamcam.tamu.edu/courses/inen416/Handouts/AGV%2CNC0Pr

esentation.html

6. http://tamcam.tamu.edu/Courses/Micro%20Controller/books/Contro

ller/KCam,%20EMC2,%20Mach3,%20TurboCNC,and%20other%2

0CNC%20related%20software%20links.htm

7. http://www.stadna.com/forums/index.php?mode=t&t=8279.html

128

Appendex

Table (1)

Table (2)

129

Table (3)

Table (4)

130

Table (5)