CNC Report

[CNC Milling Report_2010]

TITLE 

Uses Of CNC Machine

A milling machine is a machin machine e tool tool used used to machine machine solid materials materials.. Millin Milling g machines exist in two basic forms: horizontal and vertical, which terms refer to the 1

[CNC Milling Report_2010] orientation of the cutting tool spindle. Unlike a drill press, in which the workpiece is held stationary and the drill is moved vertically to penetrate the material, milling also involves movement of the workpiece against the rotating cutter, the latter of which is able to cut on its flanks as well as its tip. Workpiece and cutter movement are are preci precisel sely y contr controll olled ed to less less than than 0.001 0.001 in (0.025 (0.025 mm), mm), usuall usually y by means means of precision ground slides and leadscrews or analogous technology. Milling machines may be manually operated, mechanically automated, or digitally automated via computer numerical control (CNC). Milling machines can perform a vast number of operations, some very complex, such as slot and keyway cutting, planing, drilling, diesinking, rebating, routing, etc. Cutting fluid is often pumped to the cutting site to cool and lubricate the cut, and to sluice away the resulting swarf. swarf.

Most CNC milling machines (also called machining centers) centers) are computer controlled vertical mills with the ability to move the spindle vertically along the Z-axis. This extra degree of freedom permits their use in diesinking, engraving applications, and 2.5D surfaces such as relief sculptures. When combined with the use of conical tools or a ball a ball nose cutter , it also significantly improves milling precision without impacting speed, providing a cost-efficient alternative to most flat-surface hand-engraving work. Five-axis machining center with rotating table and computer interface CNC machines can exist in virtually any of the forms of manual machinery, like horizontal mills. The most most advanced advanced CNC milling-ma milling-machines chines,, the multi multiaxis axis machin machinee, add two more axes in addition to the three normal axes (XYZ). Horizontal milling machines also have a C or Q axis, allowing the horizontally mounted workpiece to be rotated, essentially allowing asymmetric and eccentric turning turning.. The fifth axis (B axis) controls the tilt of the tool itself. When all of these axes are used used in conjunct conjunction ion with with each other other,, extrem extremely ely compli complicate cated d geomet geometrie ries, s, even even organi organicc geometries such as a human head can be made with relative ease with these machines. But the skill to program such geometries is beyond that of most operators. Therefore, 5-axis milling machines are practically always programmed with CAM CAM..

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OBJECTIVE Each an every student will be having their own objective for it to makes their project or learning process to be done do ne well and correctly c orrectly.. Regarding this, there’s there’s some main objective o bjective which thought the student like me to successful up my project of CNC MILLING. 3


♦

Learn Learn what’s what’s the uses which h we uses of G-CODE G-CODE in whic learn how to interpret the given figure into a GCODE scale reading .

♦

Learn how to make over a project before it’s done by a machine. Some process will take over here through SIMU SIMULA LATI TION ON by usin using g EX EXSL SL WIN WIN 7 software in computer.

♦

Get Get to know know the the size sizes s and and uses uses of the the mill millin ing g cutter(cutting tool).

♦

Student learns how to change milling cutter(cutting tool).

♦

Opera Operati tion on of CNC CNC mach machin ine e can can be lear learn n by the the student.

INTRODUCTION 4

[CNC Milling Report_2010] 

World of CNC

In

Industry it is not efficient or profitable to make everyday products by hand. On a CNC machine it is possible to make hundreds or even thousands of the same item in a day. First a design is drawn using design software, then it is processed by the computer and manufactured using the CNC machine. The machine featured below is the BOXFORD DUET. This is a small CNC machine and can be used to machine woods, plastics and aluminium. In industry, CNC machines can be extremely large. The Duet is one of the smaller CNCs and is ideal for use in schools.

VICE:

This holds the material to be cut or shaped. Material must be held securely otherwise it may 'fly' out of the vice when the CNC begins to machine. Normally the vice will be like a clamp that holds the material in the correct position.

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[CNC Milling Report_2010] GUARD:

The guard protects the person using the CNC. When the CNC is machining the material small pieces can be 'shoot' off the material at high speed. This could be dangerous dangerous if a piece hit the person operating operating the machine. machine. The guard completely completely encloses the the dangerous areas of the CNC.

CHUCK:

This holds the material that is to be shaped. The material must be placed in it very carefully so that when the CNC is working the material is not thrown out at high speed.

MOTOR:

The motor is enclosed inside the machine. This is the part that rotates the chuck at high speed.

LATHE BED: The base of the machine. Usually a CNC is bolted down so that it cannot move

through the vibration of the machine when it is working. CUTTER:

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This is usually made from high quality steel and it is the part that actually cuts the material to be shaped.

Technology of CNC

1810s-1830s

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[CNC Milling Report_2010] Milling machines evolved from the practice of rotary filing. That is, running a circular cutter with file file-like -like teeth in the headstock of a lathe lathe.. Both rotary filing and later true milling were developed in order to reduce the time and effort spent on hand-filing. The full, true story of the milling machine's development will probably never be known, because much of the early development took place in individual shops where generally no one was taking down records for posterity. posterity. However, the broad outlines are known. Rotary filing long predated milling. 1840s-1860s

Some of the key men in milling machine development during this era. During this era there was a continued blind spot in milling machine design, as various designers failed to develop a truly simple and effective means of providing slide travel in all three of the archetypal milling axes (X, Y, and Z—or as they were known in the past, longitudinal, longitudinal, traverse, and vertical). Vertical Vertical positioning ideas were either absent or underdeveloped.

1860s In 1861, Frederick W. Howe asked Joseph R. Brown of Brown of Brown & Sharpe for a solution to the problem of milling spirals, such as the flutes of twist drills. These were filed by hand at the time. Brown designed a "universal milling machine" that, starting from its first sale in March 1862, was wildly successful. It solved the problem of 3-axis (XYZ) travel much more elegantly than had been done in the past, and it allowed for the milling of spirals using an indexing head fed in coordination with the table feed. The term "universal" was applied to it because it was ready for any kind of work and was not as limited limited in application application as previous designs. (Howe had designed a "universal miller" in 1852, but Brown's of 1861 is the one considered a groundbreaking success.)

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1870s-1930s Two Two firms firms which which most most domina dominated ted the millin milling g machin machine e field field during during these these decades were Brown & Sharpe and the Cincinnati Milling Machine Company. Company . However, However, hundreds hundreds of other firms firms built built milling milling machin machines es during during this time, time, and many were significant in one way or another. another. The archetypal workhorse milling machine of the late 19th and early 20th centuries was a heavy knee-andcolumn horizontal-spindle design with power table feeds, indexing head, and a stout overarm to support the arbor. Around the end of World of World War I, I, machine tool control advanced in various ways that laid the groundwork for later CNC technology. technology. The jig The jig borer popularized the ideas of coordinate dimensioning working routinely in "tenths" "tenths" as an everyday everyday machine machine capability capability;; and using the control control to go straight straight from drawing to part, circumventing jig-making. In 1920 the new tracer design of J.C. Shaw was applied to Keller tracer milling machines for die-sinking via the three-dimensional copying of a template. This made diesinking faster and easier easier just as dies dies were were in high higher er dema demand nd than than ever ever befo before, re, and was very very helpful helpful for large large steel dies such as those used to stamp sheets in automobil automobile e manufacturing. Such machines translated the tracer movements to input for servos that worked the machine leadscrews or hydraulics. 1940s-1970s By 1940 1940,, auto automa mati tion on via cams cams,, such such as in scre screw w mach machin ines es and and automa automatic tic chuck chuckers ers,, had alrea already dy been been very very well well deve develop loped ed for decades. decades. These were soon combined with with the emerging emerging technology technology of digital computers computers.. During the 1950s, numerical control made its commer commercia ciall appear appearanc ance. e. The techn technolo ology gy trans transfer fer drasti drastica cally lly adva advanc nced ed mach machin ine e to tool ol cont contro rol, l, and and deep deeply ly tran transf sfor orme med d the the cultur culture e of manuf manufact acturi uring. ng. During During the 1960s 1960s and 1970s 1970s,, NC evol evolve ved d into into CNC, CNC, data data stor storag age e and and inpu inputt medi media a evol evolve ved, d, computer computer process processing ing power power and memory memory capacit capacity y steadily steadily increased, and NC and CNC machine tools gradually disseminated from the level of huge corporations to the level of medium-sized medium-sized corporations.

1980s-Present Comput Computers ers and CNC machin machine e tools tools contin continue ue to develo develop p rapidl rapidly y. The PC revolu revolutio tion n has a great great impact impact on this this develo developme pment. nt. By the late 1980s small 8

[CNC Milling Report_2010] machin machine e shops shops had deskto desktop p comput computers ers and CNC machine machine tools. tools. After After that that hobbyists began obtaining CNC mills and lathes.

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Advantage and Disadvantage of CNC

Advantages Efficiency - Aside from the need for periodic maintenance, CNC machines can operate almost continuously. One person can oversee the operation of several CNC machines at a time. Easy Use

- CNC machines are easier for beginners to use than lathes and milling machines.

Expanding - Software changes and updates make it possible to expand the

Opti Op tion onss

No Proto Pr ototyp typee

mach ma chin ine' e'ss cap capab abil ilit itie iess rat rathe herr tha than n rep repla laci cing ng th thee mac machi hine ne..

- New desi designs gns and par parts ts can be pro progra gramme mmed d dir directl ectly y into a CNC CN C mach machine ine,, elim elimina inatin ting g the the need need to to buil build d a proto prototyp type. e.

Disadvantages Price

- CNC machines are more expensive than manually operated

machines,

although slowly coming down. Skills - The CNC machine operator only needs basic training and skills, enough to supervise several machines. In years gone by, engineers needed years of training to operate centre lathes, milling machines and other manually operated machines. This means many of the old skills are been lost. 9

[CNC Milling Report_2010] Workers

- Less workers are required to operate CNC machines

compared to manually operated machines. Investment in CNC machines can lead to unemployment. Teaching - Many countries no longer teach pupils / students how to use manually operated lathes / milling machines etc... Pupils / students no longer develop the detailed skills required by engineers of the past. These include mathematical and engineering skills.

Theory G-Code, or preparatory code or function, are functions in the Numerical control programming language. language. The G-codes are the codes that position the tool and do the actual work, as opposed to M-codes, that manages the machine; T for tool-related code codes. s. S and and F are are tool tool-S -Spe peed ed and and tool tool-F -Fee eed, d, and and fina finall lly y D-co D-code des s for for tool tool compensation. G-codes are also called preparatory codes, and are any word in a CNC program that begins with the letter 'G'. Generally it is a code telling the machine tool what type of action to perform, such as: •

rapid move

•

controlled feed move in a straight line or arc

•

series of controlled feed moves that would result in a hole being bored, a workpiece cut (routed) to a specific dimension. .

•

change a pallet a pallet

•

set tool information such as offset

There are other codes; the type codes can be thought of like registers in a computer • • • • •

X = Absolute position Y = Absolute position Z = Absolute position M = Referred to as a "Miscellaneous" function F = Feed rate

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[CNC Milling Report_2010] • • •

S = Spindle speed N = Line number R = Arc radius or optional word passed to a subprogram/canned cycle

M codes control the overall machine, causing it to stop, start, turn on coolant, etc., whereas other codes pertain to the path traversed by cutting tools. Different machine tools may use the same code to perform different functions; even machines that use the same CNC control. •

Partial list of M-Codes             

M00 = Program Stop (non-optional) M01 = Optional Stop, machine will only stop if operator selects this option M02 = End of Program M03 = Spindle on (CW rotation) M04 = Spindle on (CCW rotation) M05 = Spindle Stop M06 = Tool Change M07 = Coolant on (flood) M08 = Coolant on (mist) M09 = Coolant off M10 = Pallet clamp on M11 M11 = Pallet clamp off M30 = End of program/rewind tape (required for older CNC machines)

Common FANUC G Codes for Mill 

G00 = Rapid positioning

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G01 = Linear interpolation

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G02 = Clockwise circular interpolation

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G03 = Counter Clockwise circular interpolation

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G90 = Absolute programming (type B and C systems)

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G91 = Incremental programming (type B and C systems)

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Tools 1. Machine Of CNC MILLING ♦

Used to cut off the work piece as we stated in the G-CODE

program

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2. Milling cutter(Cutting tools) ♦

Used

to cut the work piece as we want in which the milling cutter comes in various size with its diameter.

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[CNC Milling Report_2010] 3. Cutter/Tool Holder ♦

Used to hold the milling cutter tightly because it will be

spining in high speed.

4. Vernier Caliper ♦

Used to measure the size of milling cutter(cutting tool)

manualy.

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5. Opener ♦

Use to tighten and unlock the nut which will hold the work

piece.

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6. Brush ♦

Used to clean up the wastage of work piece which has been

cuuten off from it.

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PROCEDURE OF PROJECT 

Steps Involved in SIMULATION by using (EXCL WIN 7)

1. Program of EXCL EXCL WIN 7 is clicked. 2. Then Project is clicked once its fully loaded. 3. Management is choosen and then New Project. 4. Choose Project Name : Example (HaRThi) 5. Then Fanuc OTC is clicked from the entire list, click Apply Apply once done.

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[CNC Milling Report_2010] 6. The common code such as M Code and G Code is typed from the beginning until the end. 7. Once done, its Save As(Using Same Programme Number: O0001;) 8. Once save, chose Edit on the right hand side of the program. Chan ger. 9. Then select Empty Tool Changer.

10.Select 10. Select Changer 24 and click Load Load 11.

12. Click

Select the most suitable tools (Example: End Mill d : 3mm)

to insert insert the tool in the correct correct T

13.Click 13. Click Corrections, then Measure and Close. 14. Blank Blank is clicked select The Blank Profile : Square Bar 15. Insert Insert the value of work piece from its Length, width and height and click OK. 16. Zero Zero Reference Point is clicked and its Origin is stated. 17.Once 17. Once all done, Select Simulation and then Full Sequence to view your work piece . with its project on it .

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

Steps Involved in CUTTING process by using BRIDGEPORT

VMX 600X

All of the instrument such as milling cutter(cutting tool), work piece and needed material with its tools are placed.

1.

2.

3.

Main switch of power is switched on.

Air Compressor which needed to power up the

machine is switched on. Its used when changing the Cutting Tool.

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Switch on machine is on press at NC Panel. Wait until the monitor shows its functions. 4.

5.

Pull “Emergency Stop” and Press “Power On” button.

On screen will be shown “Machine Not Reference”. Press button “JOG”, “REF RETURN” and “CYCLE START” . 6.

7.

Once the machine is start on, monitor will be showing “Spindle Warm

Up”. 8.

Press button “REF RETURN” and “Spindle %S” on the same time.

9.

Insert the program by manually key in it or insert by using computer

Use the new program name By EDIT – PROG – DIR- Insert the program number as O0013; 10.

11.

Then press + on screen. Press READ – EXEC(LSK will be blinking)

On computer, make sure its at EDIT – DATA TRANSFER – choose FILE NAME of the program which insert and press START. 12.

For work piece setting, press “HANDLE” for using “hand wheel” to manually movement. 13.

Brin Bring g the the poin pointe terr to the the work work piec piecee on the the coor coordi dina nate te of Z . Pres Presss WORKSHIFT”. Take the reading, example -467.018 and radius 2.000. 14.

X by Adjust the coordinate of X by bringing the milling cutter towards the work piece. Press WORKSHIFT”. Take the reading, example -467.018 and the radius 2.000 is been minus. Its enter on the place of G54. 15.

16.

Repeat the steps 10 for Y coordinates( coordinates(exampl examplee -434.012). -434.012). Example Example as

below. X Y

-465.018 -432.012

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[CNC Milling Report_2010] To see the coordinate X, Y and Z, bring the milling cutter(cutting tool) to the work piece by using “hand wheel”.

17.

Once u are confidence of its coordinate ORIGIN and press “POS”, and X. X will be blinking and press ORIGIN. then click X. 18.

19.

Repeat the steps of 15 for Y and Z.

20.

“PROG”

21.

“AUTO” “CYCLE START”.

22.

Cutting process will start on.

Close the machine once the work piece is taken out and clean up the machine before close it.

23.

P

24.

ress “Emergency Stop” and main switch is switched off.

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PROJECT OUTCOMES Coordinates of the work piece of “XP LOGO” based on the graph paper.

No.

COOR DINAT ES X

Y

R

1

10

20

2

25

25

20

3

40

20

20

4

45

50

5

30

55

20

6

15

50

20

7

10

20

8

45

18

9

60

13

20

10

75

18

20

11

80

48 22

[CNC Milling Report_2010] 12

65

43

20

13

50

48

20

14

45

18

15

51

53

16

66

48

20

17

81

53

20

18

86

83

19

71

78

20

20

56

83

20

21

51

53

22

46

55

23

51

85

24

36

90

20

25

21

85

20

26

16

55

27

31

60

20

28

46

55

20

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Simulation code of G90 O0001; N10 G00 G90 G54 G40 G49 G80 G17 G21; N20 M06 T1; N30 G00 G43 H01 D1 Z10.; N40 M03 S1600; N50 G00 X10. Y20. Z10.; N60 G01 Z-5. F300.; N70 G02 X25. Y25. R20.; N80 G02 X40. Y20. R20.; N90 G01 X45. Y50.; N100 G03 X30. Y55. R20.; N110 G03 X15. Y50. R20.; N120 G01 X10. Y20.; N130 G00 Z100.; N140 G00 X45. Y18. Z10.; N150 G01 Z-5. F300.; N160 G03 X60. Y13. R20.; N170 G03 X75. Y18. R20.; N180 G01 X80. Y48.; N190 G02 X65. Y43. R20.; N200 G02 X50. Y48. R20.;

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[CNC Milling Report_2010] N210 G01 X45. Y18.; N220 G00 Z100.; N230 G00 X51. Y53. Z10.; N240 G01 Z-5. F300.; N250 G03 X66. Y48. R20.; N260 G03 X81. Y53. R20.; N270 G01 X86. Y83.; N280 G02 X71. Y78. R20.; N290 G02 X56. Y83. R20.; N300 G01 X51. Y53.; N310 G00 Z100.; N320 G00 X46. Y55. Z10.; N330 G01 Z-5. F300.; N340 G01 X51. Y85.; N350 G03 X36. Y90. R20.; N360 G03 X21. Y85. R20.; N370 G01 X16. Y55.; N380 G02 X31. Y60. R20.; N390 G02 X46. Y55. R20.; N400 M05; N410 M30;

Work Method

1. The design is loaded into the computer which is attached to the CNC machine. The computer changes the design into a special code (numerical) that controls the way the CNC cuts and shapes the material.

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[CNC Milling Report_2010] 3. Knee 4 & 5. Table (x-axis slide is integral) 6. Overarm 7. Arbor (attached to spindle) A horizontal mill has the same sort of x x – y table, but the cutters are mounted on a horizontal arbor (see Arbor milling) milling) across the table. A majority of horizontal mills also feature a +15/-15 degree rotary table that allows milling at shallow angles. While endmills and the other types of tools available to a vertical mill may be used in a horizontal mill, their real advantage lies in arbormounted cutters, called side and face mills, which have a cross section rather like a circular saw, but are generally wider and smaller in diameter. Because the cutters have good support from the arbor, quite heavy cuts can be taken, enabling rapid material removal rates. These are used to mill grooves and slots. Plain mills are used to shape flat surfaces. Several cutters may be ganged together on the arbor to mill a complex shape of slots and planes. Special cutters can also cut grooves, bevels, radii, or indeed any section desired. These specialty cutters tend to be expensive. Simplex mills have one spindle, and duplex mills have two. It is also easier to cut gears on a horizontal mill.

Uses Of CNC Technology Technology

Milling machines can perform a vast number of operations, some very complex, such as slot •

Keyway Cutting

•

Planning

•

Drilling

•

Die sinking

•

Rebating

•

Routing

Cutting fluid is often pumped to the cutting site to cool and lubricate the cut, and to sluice away the resulting swarf .

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Project Based on OBJECTIVE

From the outcome, there some objective been taken to make over the project. There are some of it as list down below; I have been; 

Learned how to use G-CODE by interpret the given figure with its

scale. 

Learned how to use SIMULATION by using EXSL WIN 7 software in

computer. 

Able to learn how to adjust and operate the CNC MILLING machine

properly.

REFERENCE Web Sites •

http://www.ehow.com/facts_4830778_advantages-cnc-

machines.html •

http://www.technologystudent.com/cam/cncman4.htm

•

http://en.wikipedia.org/wiki/Milling_machine

•

http://en.wikipedia.org/wiki/G-code

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[CNC Milling Report_2010] •

http://en.wikipedia.org/wiki/Milling_cutter#Features_of_a_mill

ing_cutter

Books •

Teknologi Worksyop Worksyop – Abdul Rahman Darman

Lecturer •

Pn. Putri Irda Binti Abdul Rahman

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CNC Report

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