Jm201 - Cnc Milling
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Transcript of Jm201 - Cnc Milling
CONTENTS PAGES
INTRODUCTION
SAFETY
MACHINE
PROCEDURE
PROJECT PICTURE
CONCLUSION
DISCUSSION
INTRODUCTION
What are CNC?
CNC stands for Computer Numerical Control and it has been around since the
early 1970’s. Before it was christened CNC, it was called NC, for Numerical Control. When
computers were introduced during 1070’s, the name changed. It has stroked almost all
manufacturing forms in almost all stages of production. CNC machines either substitute
some existing manufacturing processes or combine work with them.
A CNC program is just any other set of instructions. It’s written like a sentence and
the order of operation is chronological. The machine will then execute that set of instructions
step-by-step. A special series of CNC words/codes are used to relay what the machine is
supposed to do. CNC codes begin with letter addresses (like S for spindle speed, and X, Y &
Z for common linear axis motions).
When certain codes are arranged together in a coherent method, this group of CNC
codes create a “command” that is like a sentence. A common CNC machine will only be
needing around 40-50 words/codes to program different commands
THE CAM
CAM stands for Computer Aided Manufacturing. It simplifies the programming
processes which are new, and added to the CNC program regularly. Of course, the easy
applications can be programmed with only the simplest machines around: the pen, paper
and calculator. However, more complex programs are vital regularly. It is when composing
these programs become much more tricky and (worse) tedious.
The CAM is a program that runs on a computer that aids the CNC programmer with
the programming. It also works hand-in-hand with the CAD (Computer Aided Design) design
drawing (those designs engineers compose/nurture). With the CAM helping, redefinition of
the work-piece configuration is not needed. What the CNC programmer is left to do is just to
specify the machine operations to be executed and the CAM system will compose the CNC
program automatically.
THE DNC SYSTEM
DNC stands for Distributive Numerical Control. It is a computer that is connected with
one or more CNC machines, forming a network. When a program is manually composed and
ready to be loaded to the CNC control, it is being typed right into the control. However, this is
like using the CNC machine as a luxurious keyboard. Moreover, if the CNC program is
achieved with the help of CAM, it is already in text form and ready to be loaded to the CNC
control. The DNC simply distributes the CNC program to more than one CNC machine.
Fields or industry that are using CNC machine
1. In the metal removal industry
2. In the metal fabrication industry
3. In the electrical discharge machining industry
4. In the woodworking industry
Types of CNC machines
CNC milling machines are traditionally programmed using a set of commands known as G-
codes & M-codes. These types of codes are representing specific CNC functions in
alphanumeric format.
G-codes Description
GOO Rapid positioning
G01 Linear interpolation
G02 Circular interpolation, clockwise
G03 Circular interpolation, counterclockwise
G04 Dwell
G05
P10000
High-precision contour control (HPCC)
G05.1 AI Nano contour control
Q1.
G07 Imaginary axis designation
G09 Exact stop check
G10 Programmable data input
G11 Data write cancel
G12 Full-circle interpolation, clockwise
G13 Full-circle interpolation, counterclockwise
G17 XY plane selection
G18 ZX plane selection
G19 YZ plane selection
G20 Programming in inches
G21 Programming in millimeters (mm)
G28 Return to home position (machine zero, aka machine reference point)
G30 Return to secondary home position (machine zero, aka machine reference
point)
G31 Skip function (used for probes and tool length measurement systems)
G33 Constant-pitch threading
G34 Variable-pitch threading
G40 Tool radius compensation off
G41 Tool radius compensation left
G42 Tool radius compensation right
G43 Tool height offset compensation negative
G44 Tool height offset compensation positive
G45 Axis offset single increase
G46 Axis offset single decrease
G47 Axis offset double increase
G48 Axis offset double decrease
G49 Tool length offset compensation cancel
G50 Scaling function cancel
G52 Local coordinate system (LCS)
G53 Machine coordinate system
G54 to G59 Work coordinate systems (WCSs)
G54.1 P1 to
P48
Extended work coordinate systems
G73 Peck drilling cycle for milling - high-speed (NO full retraction from pecks)
G74 Tapping cycle for milling, left hand thread, M04 spindle direction
G76 Fine boring cycle for milling
G80 Cancel canned cycle
G81 Simple drilling cycle
G82 Drilling cycle with dwell
G83 Peck drilling cycle (full retraction from pecks)
G84 Tapping cycle, right hand thread, M03 spindle direction
G84.2 Tapping cycle, right hand thread, M03 spindle direction, rigid tool holder
G90 Absolute programming
G91 Incremental programming
G92 Position register (programming of vector from part zero to tool tip)
G94 Feedrate per minute
G97 Constant spindle speed
G98 Return to initial Z level in canned cycle
G99 Return to R level in canned cycle
M-codes Description
M00 Compulsory stop
M01 Optional stop
M02 End of program
M03 Spindle on (clockwise rotation)
M04 Spindle on (counterclockwise rotation)
M05 Spindle stop
M06 Automatic tool change (ATC)
M07 Coolant on (mist)
M08 Coolant on (flood)
M09 Coolant off
M10 Pallet clamp on
M11 Pallet clamp off
M13 Spindle on (clockwise rotation) and coolant on (flood)
M19 Spindle orientation
M21 Mirror, X-axis
M22 Mirror, Y-axis
M23 Mirror OFF
M30 End of program with return to program top
M48 Federate override allowed
M49 Federate override NOT allowed
M60 Automatic pallet change (APC)
M98 Subprogram call
M99 Subprogram end
CNC Milling
Computer Numerical Control (CNC) Milling is the most common form of CNC. A milling
machine is a machine tool used to machine solid materials .Milling machines are often
classed in two basic forms, horizontal and vertical. CNC mills are classified according to the
number of axes that they passes .Axes are labeled as x and y for horizontal movement, and
z for vertical movement .A standard manual light-duty mill (such as a Bridgeport) is
typically assumed to have four axes:
1. Table x.
2. Table y.
3. Table z.
4. Milling Head z.
Other than that, CNC milling can perform the functions of drilling and often turning.
The number of axis of a milling machine is a common subject of casual "shop talk"
and is often interpreted in varying ways. A five-axis CNC milling machine has an extra axis in
the form of a horizontal pivot for the milling head, as shown below. This allows extra
flexibility for machining with the end mill at an angle with respect to the table. A six-axis CNC
milling machine would have another horizontal pivot for the milling head, this time
perpendicular to the fifth axis.
COMPENANT OF MECHINE
Objective
Introduced to CNC (computer numerical control) of its uses.
Can differentiate the programmer code of G-codes and M-codes
Can understand the description of the G-code and M-code
Can prepare programmer code for the project that have been given after been
introduced to its codes.
Know how to key-in the programmer into the computer for see its simulation.
Can operate the CNC machine without any problem.
Always aware with the vital of self, machine and workshop safety
Project
We have been given an project where we need to construct name of one of
the polytechnic in Malaysia in a graph paper with its scales for each symbol. Then,
we have prepare the programmer code for the name .We have been told that, the
project must be try its simulation before key-in into the CNC milling machine so that
the works done will more accurate or perfect .These project can be done using CNC
milling through an drilling process.
SAFETY
Self - Safety
1. Wear safety glasses and side shields at all times.
2. Do not wear rings or jewelry that could get caught in a machine.
3. Keep long hair covered or tied back while operating machine.
4. Keep hands away from moving machine parts.
5. Use proper materials to lift heavy materials. A back injury can ruin your
career.
6. Safety shoes with steel toes and oil-resistant soles should be worn to protect
our feet from dropped objects.
7. Watch out for burrs on machined parts.
8. Always obey your lecturer’s directive before doing any work.
Machine Safety
1. Do not operate a machine unless all safety guards in place.
2. Never remove chips from a moving tool.
3. Securely clamp all parts.
4. Stop the spindle completely before doing any setup or piece loading and
unloading.
5. Keep tools off the machine and its moving parts.
6. Use proper speeds and feeds. Reduce feed and speed if you notice unusual
vibration or noise.
7. Dull or damaged tools break easily and unexpectedly.
8. Make sure coolant is in “ON” mode when a project is in progress.
9. Make sure the emergency stop button at the machine is operational.
Workshop Safety
1. Keep area clean.
2. Do not play or run inside the workshop.
3. Keep the used tools in its original place.
4. Sweep up chips and clean up any oil or coolant that people could slip on.
5. Always obey the workshop safety rules and its precaution.
6. Always be aware of self-safety and machine which can cause dangerous to
our self and other people in the workshop.
7. Do not pour any slippery liquids to the ground of the workshop.
8. Make sure the workshop is clean and all the tools are in their original places
before leaving the workshop.
MACHINE
CNC Milling Machine
PROCEDURE
N01 G71 G90 G17 G40
N02 G54
N03 M27
N04 T=”DRILL 10”
N05 M06
N06 M07
N07 S1200 M03
N08 G00 X10 Y88
N09 G01 Z-5 F100
N10 G01 X10 Y90
N11 G01 X20 Y90
N12 G01 X20 Y88
N13 G00 Z10 F100
N14 G00 X15 Y90
N15 G01 Z-5 F100
N16 G01 X15 Y70
N17 G00 Z10 F100
N18 G00 X27 Y90
N19 G01 Z-5 F100
N20 G01 X25 Y90
N21 G01 X25 Y75
N22 G03 X35 Y75 I=AC(30) J=AC(75)
N23 G01 X35 Y90
N24 G01 X33 Y90
N25 G00 Z10 F100
N26 G00 X42 Y70
N27 G01 Z-5 F100
N28 G01 X40 Y70
N29 G01 X40 Y90
N30 G01 X50 Y70
N31 G01 X50 Y90
N32 G01 X40 Y90
N33 G00 Z10 F100
N34 G00 X12 Y60
N35 G01 Z-5 F100
N36 G01 X10 Y60
N37 G01 X10 Y40
N38 G01 X12 Y40
N39 G00 Z10 F100
N40 G00 X10 Y40
N41 G01 Z-5 F100
N42 G01 X20 Y40
N43 G01 X20 Y60
N44 G01 X10 Y60
N45 G00 Z10 F100
N46 G00 X10 Y50
N47 G01 Z-5 F100
N48 G01 X20 Y50
N49 G00 Z10 F100
N50 G00 X27 Y60
N51 G01 X25 Y60
N52 G01 X25 Y45
N53 G03 X35 Y45 I=AC(30) J=AC(45)
N54 G01 X35 Y60
N55 G01 X33 Y60
N56 G00 Z10 F100
N57 G00 X42 Y45
N58 G01 Z-5 F100
N59 G01 X40 Y45
N60 G03 X45 Y50 I=AC(45) J=AC(45)
N61 G02 X50 Y55 I=AC(45) J=AC(55)
N62 G01 X40 Y55
N63 G00 Z10 F100
N64 G00 X57 Y45
N65 G01 Z-5 F100
N66 G01 X55 Y45
N67 G03 X60 Y50 I=AC(60) J=AC(45)
N68 G02 X65 Y55 I=AC(60) J=AC(55)
N69 G01 X63 Y55
N70 G00 Z10 F100
N71 G00 X80 Y50
N72 G01 Z-5 F100
N73 G01 X80 Y60
N74 G01 X75 Y60
N75 G03 X70 Y55 I=AC(75) J=AC(55)
N76 G01 X70 Y45
N77 G03 X75 Y40 I=AC(75) J=AC(45)
N78 G01 X80 Y40
N79 G01 X80 Y42
N80 G00 Z10 F100
N81 G00 X70 Y50
N82 G01 Z-5 F100
N83 G01 X80 Y50
N84 G00 Z10 F100
N85 G00 X85 Y58
N86 G01 Z-5 F100
N87 G01 X85 Y60
N88 G01 X95 Y60
N89 G01 X95 Y50
N90 G00 Z10 F100
N91 G00 X90 Y60
N92 Z-5 F100
N93 G01 X90 Y40
N94 G01 X85 Y40
N95 G01 X85 Y42
N96 G01 X85 Y40
N97 G01 X95 Y40
N98 G01 X95 Y42
N99 G00 Z10 F100
N100 G00 X102 Y40
N101 Z-5 F100
N102 G01 X100 Y40
N103 G01 X100 Y60
N104 G01 X110 Y40
N105 G01 X110 Y60
N106 G01 X108 Y60
N107 G00 Z10 F100
N108 G00 X10 Y30
N109 Z-5 F100
N110 G01 X10 Y10
N111 G01 X15 Y10
N112 G03 X20 Y15 I=AC(15) J=AC(15)
N113 G01 X20 Y25
N114 G03 X15 Y30 I=AC(15) J=AC(25)
N115 G01 X10 Y30
N116 G01 X10 Y10
N117 G00 Z10 F100
N118 G00 X27 Y10
N119 Z-5 F100
N120 G01 X25 Y10
N121 G01 X25 Y25
N122 G02 X35 Y25 I=AC(30) J=AC(25)
N123 G01 X35 Y10
N124 G01 X33 Y10
N125 G00 Z10 F100
N126 G00 X25 Y20
N127 Z-5 F100
N128 G01 X35 Y20
N129 G00 Z10 F100
N130 G00 X40 Y20
N131 Z-5 F100
N132 G01 X40 Y30
N133 G01 X50 Y30
N134 G01 X50 Y20
N135 G00 Z10 F100
N136 G00 X45 Y30
N137 Z-5 F100
N138 G01 X45 Y10
N139 G00 Z10 F100
N140 G00 X55 Y25
N141 Z-5 F100
N142 G01 X65 Y15
N143 G01 X65 Y25
N144 G03 X55 Y25 I=AC(60) J=AC(25)
N145 G01 X55 Y15
N146 G03 X65 Y15 I=AC(60) J=AC(15)
N147 G00 Z10 F100
N148 G00 X80 Y25
N149 Z-5 F100
N150 G01 X90 Y15
N151 G01 X90 Y25
N152 G03 X80 Y25 I=AC(85) J=AC(25)
N153 G01 X80 Y15
N154 G03 X90 Y15 I=AC(85) J=AC(15)
N155 G00 Z10 F100
N156 G00 X97 Y10
N157 Z-5 F100
N158 G01 X95 Y10
N159 G01 X95 Y30
N160 G01 X105 Y10
N161 G01 X105 Y30
N162 G01 X103 Y30
N163 G00 Z10 F100
N164 G00 X112 Y10
N165 Z-5 F100
N166 G01 X110 Y10
N167 G01 X110 Y30
N168 G01 X120 Y10
N169 G01 X120 Y30
N170 G01 X110 Y30
N171 G00 Z10 F100
N172 M27
N173 T0
N174 M06
N175 M30
PROJECT PICTURE
CONCLUSION
As a conclusion, the CNC milling machines are easy to be operate if we know
and understand about the machine operation very well. Other than that, we need to
know about the programmer code which is G-code and M-code to operate the
machine. It is because this CNC milling machine are an automatically control
machine with the codes and it’s not a manually control machine. We have been
emphasizing on the safety when we are in the workshop.
Finally, we are managed to achieve our objective which to done an program
for an project that have been given by the lecturer. We have been told to prepare the
program to key-in the program into computer to see it simulation of the project before
it has been tested or key-in into the CNC milling machine. We need to done it
because we need to obtain an perfect project without any mistake because the CNC
milling machine is an automatic machine. At the end, our project simulation are
success and its perfect.
DISCUSSION
.: How to solve the problem when the result design difference as we want?
- Firstly, check again the code one by one
- Then, try to change the code when we fell wrong
- After that, try to make change repeat until the design correct same as we want