الكتاب الشامل فى ماكينات CNC Programming Handbook – CNC
الكتاب الشامل فى ماكينات CNC
CNC Programming Handbook
A Comprehensive Guide to Practical CNC Programming
Second Edition
Peter Smid
TABLE OF CONTENTS
1 – NUMERICAL CONTROL 1 Axes and Planes
Point of Origin
Quadrants
Right Hand Coordinate System
MACHINE GEOMETRY
Axis Orientation – Milling
Axis Orientation – Turning
Additional Axes
DEFINITION OF NUMERICAL CONTROL
NC and CNC Technology
CONVENTIONAL AND CNC MACHINING
NUMERICAL CONTROL ADVANTAGES
Setup Time Reduction
Lead Time Reduction
Accuracy and Repeatability
Contouring of Complex Shapes
Simplified Tooling and Work Holding
Cutting Time and Productivity Increase
TYPES OF CNC MACHINE TOOLS
Mills and Machining Centers
Lathes and Turning Centers
PERSONNEL FOR CNC
CNC Programmer
CNC Machine Operator
SAFETY RELATED TO CNC WORK
3 5 – CONTROL SYSTEM 19
3
. 4
GENERAL DESCRIPTION
Operation Panel
Screen Display and Keyboard
Handle
SYSTEM FEATURES
Parameter Settings
System Defaults
Memory Capacity
MANUAL PROGRAM INTERRUPTION.
Single Block Operation
Feedhold
Emergency Stop
MANUAL DATA INPUT – MDI .
PROGRAM DATA OVERRIDE .
Rapid Motion Override
Spindle Speed Override
Feedrate Override
Dry Run Operation
Z Axis Neglect
Manual Absolute Setting
Sequence Return
Auxiliary Functions Lock
Machine Lock
Practical Applications
SYSTEM OPTIONS
Graphic Display
In-Process Gauging
Stored Stroke Limits
Drawing Dimensions Input
Machining Cycles
Cutting Tool Animation
Connection to External Devices
2 – CNC MILLING 7 25
25
CNC MACHINES – MILLING
Types of Milling Machines .
Machine Axes
Vertical Machining Centers .
Horizontal Machining Centers
Horizontal Boring Mill .
Typical Specifications .
3 – C N C TURNING 11 28
28
CNC MACHINES – TURNING 29
Types of CNC Lathes
Number of Axes
AXES DESIGNATION
Two-axis Lathe
Three-axis Lathe
Four-axis Lathe
Six-axis Lathe
FEATURES AND SPECIFICATIONS
Typical Machine Specifications .
Control Features
. 14 6 – PROGRAM PLANNING 31
STEPS IN PROGRAM PLANNING .
INITIAL INFORMATION .
MACHINE TOOLS FEATURES
Machine Type and Size
31
4 – COORDINATE GEOMETRY 15
31
REAL NUMBER SYSTEM 31
RECTANGULAR COORDINATE SYSTEM .
I XX Table of Contents
Control System
PART COMPLEXITY
MANUAL PROGRAMMING
Disadvantages
Advantages
CAD/CAM AND CNC
Integration
Future of Manual Programming
TYPICAL PROGRAMMING PROCEDURE .
PART DRAWING
Title Block
Dimensioning
Tolerances
Surface Finish
Drawing Revisions
Special Instructions
METHODS SHEET
MATERIAL SPECIFICATIONS
Material Uniformity
Machinability Rating
MACHINING SEQUENCE
TOOLING SELECTION
PART SETUP
Setup Sheet
TECHNOLOGICAL DECISIONS .
Cutter Path
Machine Power Rating
Coolants and Lubricants
WORK SKETCH AND CALCULATIONS .
Identification Methods
QUALITY IN CNC PROGRAMMING
31
8 – PREPARATORY COMMANDS 47
32
32
DESCRIPTION AND PURPOSE.
APPLICATIONS FOR MILLING .
APPLICATIONS FOR TURNING
G CODES IN A PROGRAM BLOCK
Modality of G-commands
Conflicting Commands in a Block .
Word Order in a Block
GROUPING OF COMMANDS .
Group Numbers 51
. 34
35 G CODE TYPES 52
35
G Codes and Decimal Point 52
36
36
36 9 – MISCELLANEOUS FUNCTIONS 53
36
DESCRIPTION AND PURPOSE.
Machine Related Functions .
Program Related Functions .
TYPICAL APPLICATIONS
Applications for Milling
Applications for Turning . ,
Special MDI Functions
Application Groups
M FUNCTIONS IN A BLOCK .
Startup of M Functions
Duration of M Functions
PROGRAM FUNCTIONS
Program Stop
Optional Program Stop
Program End
Subprogram End
MACHINE FUNCTIONS
Coolant Functions
Spindle Functions
Gear Range Selection
Machine Accessories
7 – PART PROGRAM STRUCTURE 41 58
58
BASIC PROGRAMMING TERMS . 59
Character
Word
Block
Program
PROGRAMMING FORMATS
WORD ADDRESS FORMAT
FORMAT NOTATION
Short Forms
Milling System Format
Turning System Format
Multiple Word Addresses
SYMBOLS IN PROGRAMMING .
Plus and Minus Sign
PROGRAM HEADER
TYPICAL PROGRAM STRUCTURE.
10 – SEQUENCE BLOCK 61
42
42
BLOCK STRUCTURE
Building the Block Structure
Block Structure for Milling
PROGRAM IDENTIFICATION .
Program Number
Program Name
SEQUENCE NUMBERS
Sequence Number Command
Sequence Block Format
Numbering Increment
Long Programs and Block Numbers .
END OF BLOCK CHARACTER .
STARTUP BLOCK OR SAFE BLOCK .
65Table of Contents XI
PROGRAM COMMENTS
CONFLICTING WORDS IN A BLOCK
MODAL PROGRAMMING VALUES
EXECUTION PRIORITY
66 Exact Stop Command
Exact Stop Mode Command
Automatic Corner Override .
Tapping Mode
Cutting Mode
CONSTANT FEEDRATE
Circular Motion Feedrates .
MAXIMUM FEEDRATE .
Maximum Feedrate Considerations
11 – INPUT OF DIMENSIONS
ENGLISH AND METRIC UNITS
Comparable Unit Values
ABSOLUTE AND INCREMENTAL MODES
Preparatory Commands G90 and G91 .
Absolute Data Input – G90
Incremental Data Input – G91
Combinations in a Single Block
DIAMETER PROGRAMMING .
MINIMUM MOTION INCREMENT
FORMAT OF DIMENSIONAL INPUT .
Full Address Format
Zero Suppression
Decimal Point Programming
Input Comparison
CALCULATOR TYPE INPUT .
69
70 FEEDHOLD AND OVERRIDE . 91
Feedhold Switch
Feedrate Override Switch .
Feedrate Override Functions
72 E ADDRESS IN THREADING 92
72
73 14 – TOOL FUNCTION 93
73
73 T FUNCTION FOR MACHINING CENTERS
Tool Storage Magazine
Fixed Tool Selection
Random Memory Tool Selection
Registering Tool Numbers
Programming Format
Empty Tool or Dummy Tool
TOOL CHANGE FUNCTION – M06 .
Conditions for Tool Change
AUTOMATIC TOOL CHANGER – ATC
Typical ATC System
Maximum Tool Diameter
Maximum Tool Length
Maximum Tool Weight
ATC Cycle
MDI Operation
PROGRAMMING THE ATC
Single Tool Work
Programming Several Tools
Keeping Track of Tools
Any Tool in Spindle – Not the First
First Tool in the Spindle
No Tool in the Spindle
First Tool in the Spindle with Manual Change 101
No Tool in the Spindle with Manual Change
First Tool in the Spindle and an Oversize Tool 102
No Tool in the Spindle and an Oversize Tool
T FUNCTION FOR LATHES .
Lathe Tool Station
Tool Indexing
TOOL OFFSET REGISTERS .
Geometry Offset
Wear Offset
Wear Offset Adjustment
The R and T Settings
12 – SPINDLE CONTROL
SPINDLE FUNCTION
Spindle Speed Input
DIRECTION OF SPINDLE ROTATION
Direction for Milling
Direction for Turning
Direction Specification
Spindle Startup
SPINDLE STOP
SPINDLE ORIENTATION
SPINDLE SPEED – R/MIN
SPINDLE SPEED – SURFACE
Material Machinability
Spindle Speed – English Units
Spindle Speed – Metric Units
CONSTANT SURFACE SPEED
Maximum Spindle Speed Setting
Part Diameter Calculation in CSS
13 – FEEDRATE CONTROL
FEEDRATE CONTROL
FEEDRATE FUNCTION
Feedrate per Minute
Feedrate per Revolution
FEEDRATE SELECTION
ACCELERATION AND DECELERATION .
88 15 – REFERENCE POINTS
88 REFERENCE POINT GROUPS 107XII Table of Contents
TOOL SETUP
Center Line Tools
Turning Tools
Boring Tools
Command Point and Tool Work Offset
Reference Po ;nt Groups Relationship 129
MACHINE REFERENCE POINT .
-etum to Machine Zero
PART REFERENCE POINT
-‘ocram Zero Selection
-‘ogram Zero – Machining Centers.
Drogram Zero – Lathes
TOOL REFERENCE POINT
112 19 – TOOL LENGTH OFFSET 131
112
GENERAL PRINCIPLES
Actual Tool Length
Gauge Line
Table Top Face
TOOL LENGTH OFFSET COMMANDS
Distance-To-Go in Z Axis
TOOL LENGTH SETUP
On-Machine Tool Length Setting
Off-Machine Tool Length Setting
Tool Length Offset Value Register
Z AXIS RELATIONSHIPS
Preset Tool Length
Tool Length by Touch Off
Using a Master Tool Length
G43-G44 Difference
PROGRAMMING FORMATS
Tool Length Offset not Available
Tool Length Offset and G92
Tool Length Offset and G54-G59
Tool Length Offset and Multiple Tools
CHANGING TOOL LENGTH OFFSET .
HORIZONTAL MACHINE APPLICATION
TOOL LENGTH OFFSET CANCEL
16 – REGISTER COMMANDS
POSITION REGISTER COMMAND . 113 132
Position Register Definition 1 3 2
Programming Format
Tool Position Setting
MACHINING CENTERS APPLICATION .
Tool Set at Machine Zero
Tool Set Away from Machine Zero
Position Register in Z Axis
Programming Example
LATHE APPLICATION
Tool Setup
Three-Tool Setup Groups
Center Line Tools Setup
External Tools Setup
Internal Tool Setup
Corner Tip Detail
Programming Example
POSITION COMPENSATION
DESCRIPTION
Programming Commands
Programming Format
Incremental Mode
Motion Length Calculation
Position Compensation Along the Z axis
Using G47 and G48
Face Milling
119 20 – RAPID POSITIONING
RAPID TRAVERSE MOTION
GOO Command
RAPID MOTION TOOL PATH
Single Axis Motion
Multiaxis Motion
Straight Angular Motion
Reverse Rapid Motion
TYPE OF MOTION & TIME COMPARISON .
REDUCTION OF RAPID MOTION RATE
RAPID MOTION FORMULAS
APPROACH TO THE PART
18 – WORK OFFSETS
WORK AREAS AVAILABLE
Additional Work Offsets
WORK OFFSET DEFAULT AND STARTUP .
Work Offset Change
2 Axis Application
HORIZONTAL MACHINE APPLICATION
EXTERNAL WORK OFFSETS
LATHE APPLICATIONS
Types of Offsets
Geometry Offset
Wear Offset
Tool and Offset Numbers
127 21 – MACHINE ZERO RETURN
128 MACHINE REFERENCE POSITION .
Machining Centers
Lathes
Setting the Machine Axes
Program Commands
Command Group
LONG DWELL TIME
Machine Warm-Up
X Axis is the Dwelling Axis
Safety and Dwell
FIXED CYCLES AND DWELL
RETURN TO PRIMARY MACHINE ZERO .
Intermediate Point
Absolute and Incremental Mode
Return from the Z Depth Position
Axes Return Required for the ATC
Zero Return for CNC Lathes
RETURN POSITION CHECK COMMAND .
RETURN FROM MACHINE ZERO POINT .
RETURN TO SECONDARY MACHINE ZERO
157 25 – FIXED CYCLES 177
POINT-TO-POINT MACHINING
Single Tool Motions vs. Fixed Cycles
FIXED CYCLE SELECTION
PROGRAMMING FORMAT
GENERAL RULES
ABSOLUTE AND INCREMENTAL VALUES .
INITIAL LEVEL SELECTION
R LEVEL SELECTION
Z DEPTH CALCULATIONS
DESCRIPTION OF FIXED CYCLES .
G81 – Drilling Cycle
G82 – Spot-Drilling Cycle
G83 – Deep Hole Drilling Cycle – Standard .
G73 – Deep Hole Drilling Cycle – High Speed
G84 – Tapping Cycle – Standard
G74 – Tapping Cycle – Reverse
G85 – Boring Cycle
G86 – Boring Cycle
G87 – Backboring Cycle
G88 – Boring Cycle
G89 – Boring Cycle
G76 – Precision Boring Cycle
FIXED CYCLE CANCELLATION
FIXED CYCLE REPETITION
The L or K Address
LO or KO in a Cycle
22 – LINEAR INTERPOLATION
LINEAR COMMAND . 159
Start and End of the Linear Motion
Single Axis Linear Interpolation .
Two Axes Linear Interpolation
Three Axis Linear Interpolation .
PROGRAMMING FORMAT .
LINEAR FEEDRATE .
Feedrate Range
Individual Axis Feedrate
PROGRAMMING EXAMPLE .
BLOCK SKIP FUNCTION
TYPICAL APPLICATIONS
BLOCK SKIP SYMBOL
CONTROL UNIT SETTING . ,
BLOCK SKIP AND MODAL COMMANDS
PROGRAMMING EXAMPLES
Variable Stock Removal
Machining Pattern Change
Trial Cut for Measuring
Program Proving
Barfeeder Application
Numbered Block Skip
MACHINING HOLES 191
SINGLE HOLE EVALUATION
Tooling Selection and Applications
Program Data
DRILLING OPERATIONS .
Types of Drilling Operations
Types of Drills
Programming Considerations
Nominal Drill Diameter
Effective Drill Diameter
Drill Point Length
Center Drilling
Through Hole Drilling
Blind Hole Drilling
Flat Bottom Drilling
Indexable Insert Drilling
PECK DRILLING
Typical Peck Drilling Application .
Calculating the Number of Pecks
24 – DWELL COMMAND
PROGRAMMING APPLICATIONS
Applications for Cutting
Applications for Accessories .
DWELL COMMAND .
Dwell Command Structure
DWELL TIME SELECTION .
SETTING MODE AND DWELL
Time Setting
Number of Revolutions Setting
MINIMUM DWELL .
NUMBER OF REVOLUTIONS
System Setting
Time Equivalent
Selecting the Number of Pecks
Controlling Breakthrough Depth
REAMING
Reamer Design
Spindle Speeds for Reaming
Feedrates for Reaming
Stock Allowance
Other Reaming Considerations
SINGLE POINT BORING
Single Point Boring Tool
Spindle Orientation
Block Tools
BORING WITH A TOOL SHIFT
Precision Boring Cycle G76
Backboring Cycle G87
Programming Example
Precautions in Programming and Setup.
ENLARGING HOLES
Countersinking
Counterboring
Spotfacing
MULTILEVEL DRILLING
WEB DRILLING
TAPPING
Tap Geometry
Tapping Speed and Feedrate
Pipe Taps
Tapping Check List
HOLE OPERATIONS ON A LATHE .
Tool Approach Motion
Tool Return Motion
Drilling and Reaming on Lathes
Peck Drilling Cycle – G74
Tapping on Lathes
Other Operations
FACE MILLING
CUTTER SELECTION
Basic Selection Criteria
Face Mill Diameter
Insert Geometry
CUTTING CONSIDERATIONS
Angle of Entry
Milling Mode
Number of Cutting Inserts
PROGRAMMING TECHNIQUES
Single Face Mill Cut
Multiple Face Mill Cuts
USING POSITION COMPENSATION .
CIRCULAR INTERPOLATION
ELEMENTS OF A CIRCLE .
Radius and Diameter
Circle Area and Circumference
QUADRANTS
Quadrant Points
PROGRAMMING FORMAT
Arc Cutting Direction
Circular Interpolation Block
Arc Start and End Points
Arc Center and Radius
Arc Center Vectors
Arc in Planes
RADIUS PROGRAMMING
Blend Radius
Partial Radius
FULL CIRCLE PROGRAMMING .
Boss Milling
Internal Circle Cutting – Linear Start
Internal Circle Cutting – Circular Start
Circle Cutting Cycle
ARC PROGRAMMING
FEEDRATE FOR CIRCULAR MOTION
Feedrate for Outside Arcs
Feedrate for Inside Arcs
PATTERN OF HOLES
TYPICAL HOLE PATTERNS .
RANDOM HOLE PATTERN .
STRAIGHT ROW HOLE PATTERN .
ANGULAR ROW HOLE PATTERN .
Pattern Defined by Coordinates
Pattern Defined by Angle
CORNER PATTERN
GRID PATTERN
Angular Grid Pattern
ARC HOLE PATTERN
BOLT HOLE CIRCLE PATTERN
Bolt Circle Formula
Pattern Orientation
POLAR COORDINATE SYSTEM
Plane Selection . .
Order of Machining
CUTTER RADIUS OFFSET
MANUAL CALCULATIONS
Tool Path Center Points
Cutter Radius
Center Points Calculation
COMPENSATED CUTTER PATH .
Types of Cutter Radius Offset .
Definition and Applications
PROGRAMMING TECHNIQUES .
Direction of Cutting Motion
251Table of Contents XV
Left or Right – not CW or CCW
Offset Commands
Radius of the Cutter
History of Offset Types
Programming Format
Address H or D ?
Geometry and Wear Offsets
APPLYING CUTTER RADIUS OFFSET .
Startup Methods
Offset Cancellation
Cutter Direction Change
HOW THE RADIUS OFFSET WORKS .
Look-Ahead Offset Type
Rules for Look-Ahead Cutter Radius Offset
Radius of the Cutter
Radius Offset Interference
Single vs. Multiaxis Startup
OVERVIEW OF GENERAL RULES
PRACTICAL EXAMPLE – MILLING
Part Tolerances
Measured Part Size
Programmed Offsets
D Offset Amount – General Setting
Offset Adjustment
Offset for External Cutting
Offset for Internal Cutting
One Offset or Multiple Offsets?
Preventing a Scrap
Program Data – Nominal or Middle?
TOOL NOSE RADIUS OFFSET .
Tool Nose Tip
Radius Offset Commands
Tool Tip Orientation
Effect of Tool Nose Radius Offset
Sample Program
Minimum Clearance Required
Change of Motion Direction
High Speed Steel End Mills
Solid Carbide End Mills
Indexable Insea End Mills .
Relief Angles
End Mill Size
Number of Flutes
SPEEDS AND FEEDS .
Coolants and Lubricants
Tool Chatter
STOCK REMOVAL .
Plunge Infeed
In and Out Ramping .
Direction of Cut
Width and Depth of Cut
260 33 – SLOTS AND POCKETS 281
261
OPEN AND CLOSED BOUNDARY
Open Boundary
Closed Boundary
PROGRAMMING SLOTS .
Open Slot Example
Closed Slot Example
POCKET MILLING
General Principles
Pocket Types
RECTANGULAR POCKETS
Stock Amount
Stepover Amount
Length of Cut
Semifinishing Motions
Finishing Tool Path
Rectangular Pocket Program Example
CIRCULAR POCKETS
Minimum Cutter Diameter
Method of Entry
Linear Approach
Linear and Circular Approach
Roughing a Circular Pocket
CIRCULAR POCKET CYCLES
31 – PLANE SELECTION
WHAT IS A PLANE?
MACHINING IN PLANES
Mathematical Planes
Machine Tool Planes
Program Commands for Planes Definition.
Default Control Status
STRAIGHT MOTION IN PLANES
CIRCULAR INTERPOLATION IN PLANES
G17-G18-G19 as Modal Commands .
Absence of Axis Data in a Block
Cutter Radius Offset in Planes
PRACTICAL EXAMPLE
FIXED CYCLES IN PLANES .
TURNING AND BORING
TOOL FUNCTION – TURNING
T Address
LATHE OFFSETS
Offset Entry
Independent Tool Offset
Tool Offset with Motion
Offset Change
MULTIPLE OFFSETS .
General Approach
Diameter Tolerances
Shoulder Tolerances
Diameter and Shoulder Tolerances
OFFSET SETTING
PERIPHERAL MILLING
END MILLS 275 298XVI Table of Contents
FUNCTIONS FOR GEAR RANGES
AUTOMATIC CORNER BREAK .
Chamfering at 45 Degrees
Blend Radius at 90 Degrees .
Programming Conditions
Programming Example
ROUGH AND FINISHED SHAPE .
Rough Operations
Finish Operations
Stock and Stock Allowance .
PROGRAMMING A RECESS
SPINDLE SPEED IN CSS MODE .
LATHE PROGRAM FORMAT
Program Format – Templates .
General Program Format
Approach to the Part
298 G70 Cycle Format – All Controls
BASIC RULES FOR G70-G73 CYCLES
G74 – PECK DRILLING CYCLE
G74 Cycle Format – 10T/11T/15T
G74 Cycle Format – 0T/16T/18T/20T/21T .
G75 – GROOVE CUTTING CYCLE
G75 Cycle Format – 10T/11T/15T
G75 Cycle Format – 0T/16T/18T/20T/21T .
BASIC RULES FOR G74 AND G75 CYCLES .
GROOVING ON LATHES
306 GROOVING OPERATIONS
Main Grooving Applications
Grooving Criteria
GROOVE SHAPE
Nominal Insert Size
Insert Modification
GROOVE LOCATION
GROOVE DIMENSIONS
Groove Position
Groove Depth
SIMPLE GROOVE PROGRAMMING .
PRECISION GROOVING TECHNIQUES
Groove Width Selection
Machining Method
Finishing Allowances
Groove Tolerances
Groove Surface Finish
MULTIPLE GROOVES
FACE GROOVES
Radial Clearance
Face Grooving Program Example
CORNER GROOVES / NECK GROOVES
GROOVING CYCLES
G75 Cycle Applications
Single Groove with G75
Multiple Grooves with G75
SPECIAL GROOVES
GROOVES AND SUBPROGRAMS
35 – LATHE CYCLES
STOCK REMOVAL ON LATHES 324
Simple Cycles
Complex Cycles
PRINCIPLES OF LATHE CYCLES
G90 – STRAIGHT CUTTING CYCLE .
Cycle Format
Straight Turning Example
Taper Cutting Example
Straight and Taper Cutting Example
G94 – FACE CUTTING CYCLE
Cycle Format
MULTIPLE REPETITIVE CYCLES
General Description
Cycle Format Types
Cutting Cycles and Part Contour
Chipbreaking Cycles
CONTOUR CUTTING CYCLES
Boundary Definition
Start Point and the Points P and Q
TYPE I AND TYPE II CYCLES
Programming Type I and Type II Cycles
Cycle Formatting
G71 – STOCK REMOVAL IN TURNING
G71 Cycle Format – 10T/11T/15T
G71 Cycle Format – 0T/16T/18T/20T/21T .
G71 for External Roughing
G71 for Internal Roughing
Direction of Cutting in G71
G72 – STOCK REMOVAL IN FACING .
G72 Cycle Format – 10T/11T/15T
G72 Cycle Format – 0T/16T/18T/20T/21T .
G73 – PATTERN REPEATING CYCLE .
G73 Cycle Format – 10T/11T/15T
G73 Cycle Format – 0T/16T/18T/20T/21T .
G73 Example of Pattern Repeating
G70 – CONTOUR FINISHING CYCLE .
– PART-OFF 335
PART-OFF PROCEDURE .
Parting Tool Description .
Tool Approach Motion .
Stock Allowance
Tool Return Motion
Part-off with a Chamfer .
Preventing Damage to the Part
38 – SINGLE POINT THREADING 339
320Table of Contents XVII
THREADING ON CNC LATHES
Form of a Thread
Threading Operations
TERMINOLOGY OF THREADING
THREADING PROCESS
Steps in Threading
Thread Start Position
Thread Cutting Diameter and Depth
Thread Cutting Motion
Retract from Thread
Return to Start Position
THREADING FEED AND SPINDLE SPEED 344
Threading Feedrate Selection
Spindle Speed Selection
Maximum Threading Feedrate
Lead Error
TOOL REFERENCE POINT
BLOCK-BY-BLOCK THREADING .
BASIC THREADING CYCLE – G92
MULTIPLE REPETITIVE CYCLE – G76
G76 Cycle Format – 10T/11T/l5T
G76 Cycle Format – 0T/16T/18T
Programming Example
First Thread Calculation
THREAD INFEED METHODS
Radial Infeed
Compound Infeed
Thread Insert Angle – Parameter A
Thread Cutting Type – Parameter P
ONE-BLOCK METHOD CALCULATIONS.
Initial Considerations
Z Axis Start Position Calculation
THREAD RETRACT MOTION
Thread Pullout Functions
Single Axis Pullout
Two-Axis Pullout
HAND OF THREAD
THREADING TO A SHOULDER .
Insert Modification
Program Testing
OTHER THREAD FORMS
Thread Depth
TAPERED THREAD
Depth and Clearances
Taper Calculation
Block by Block Taper Thread
Tapered Thread Using a Simple Cycle
Tapered Thread and a Multi Repetitive Cycle
MULTISTART THREAD
Threading Feedrate Calculation
Shift Amount
Application Example
THREAD RECUTTING
339
339 39 – SUBPROGRAMS 367
340
MAIN PROGRAM AND SUBPROGRAMS .
Subprogram Benefits
Identification of Subprograms
SUBPROGRAM FUNCTIONS
Subprogram Call Function
Subprogram End Function
Block Number to Return to
Number of Subprogram Repetitions
L0 in a Subprogram Call
SUBPROGRAM NUMBERING
Organized Approach
Protected Subprograms
SUBPROGRAM DEVELOPMENT
Repeating Pattern Recognition
Tool Motion and Subprograms
Modal Values and Subprograms
MULTI LEVEL NESTING
One Level Nesting
Two Level Nesting
Three Level Nesting
Four Level Nesting
Nesting Applications
CONTOURING WITH A SUBPROGRAM
TOOL CHANGE SUBPROGRAM
100 000 000 HOLE GRID
40 – DATUM SHIFT
DATUM SHIFT WITH G92 OR G50
Program Zero Shift
LOCAL COORDINATE SYSTEM .
G52 Command
MACHINE COORDINATE SYSTEM
DATA SETTING
Data Setting Command
Coordinate Mode
WORK OFFSETS
Standard Work Offset Input
Additional Work Offset Input
External Work Offset Input
TOOL LENGTH OFFSETS
Valid Input Range
CUTTER RADIUS OFFSETS
LATHE OFFSETS
MDI DATA SETTING
PROGRAMMABLE PARAMETER ENTRY.
Modal G10 Command
Parameters Notation
Program Portability
Bit Type Parameter
Effect of Block Numbers
392XVIII Table of Contents
BARFEEDER ATTACHMENT .
Bar Stopper
ADDITIONAL OPTIONS
Part Catcher or Part Unloader .
Continuous Operation
Parts Counter
Pull-Out Finger
PROGRAMMING EXAMPLE .
41 – MIRROR IMAGE
BASIC RULES OF MIRROR IMAGE .
’oolPathDirection
C’.gmal Tool Path
Mirror Axis
Sign of Coordinates
Milling Direction
Arc Motion Direction
Program Start and End
MIRROR IMAGE BY SETTING
Control Setting
Programming – Manual Mirror Setting
PROGRAMMABLE MIRROR IMAGE .
Mirror Image Functions
Simple Mirror Image Example
Complete Mirror Image Example
MIRROR IMAGE ON CNC LATHES .
45 – HELICAL MILLING
HELICAL MILLING OPERATION
Helical Interpolation
Programming Format
Arc Modifiers for Helical Interpolation
Applications and Usage
THREAD MILLING
Applying Thread Milling
Conditions for Thread Milling
Thread Milling Tool
Premachining Requirements
Clearance Radius
Productivity of Thread Milling
THE HELIX
THREAD MILLING EXAMPLE
Straight Thread
Initial Calculations
Starting Position
Motion Rotation and Direction
Lead-In Motions
Thread Rise Calculation
Milling the Thread
Lead-Out Motions
Complete Program
External Thread Milling
Tapered Thread Milling
Further Considerations
THREAD MILLING SIMULATION METHOD .
HELICAL RAMPING
42 – COORDINATE ROTATION
ROTATION COMMANDS . 419
Center of Rotation
Radius of Rotation
Coordinate Rotation Cancel
Common Applications
PRACTICAL APPLICATION
43 – SCALING FUNCTION
DESCRIPTION
Scaling Function Usage .
PROGRAMMING FORMAT .
Scaling Center
Scaling Factor
Rounding Errors in Scaling
PROGRAM EXAMPLES
46 – HORIZONTAL MACHINING 429
44 – CNC LATHE ACCESSORIES 409
INDEXING AND ROTARY AXES .
INDEXING TABLE (B AXIS)
Units of Increment
Direction of Indexing
Table Clamp and Unclamp Functions
Indexing in Absolute and Incremental Mode .
B AXIS AND OFFSETS
Work Offset and B Axis
Tool Length Offset and B Axis
RETURN TO MACHINE ZERO .
INDEXING AND A SUBPROGRAM
COMPLETE PROGRAM EXAMPLE
AUTOMATIC PALLET CHANGER – APC .
429
CHUCK CONTROL 409
Chuck Functions
Chucking Pressure
Chuck Jaws
TAILSTOCK AND QUILL
Tailstock Body
Quill
Center
Quill Functions
Programmable Tailstock
Safety Concerns
BI-DIRECTIONAL TURRET INDEXING
Programming Example
RUNNING THE FIRST PART .
PROGRAM CHANGES
Program Upgrading
Program Updating
Documentation Change
ALTERNATE MACHINE SELECTION .
MACHINE WARM UP PROGRAM .
CNC MACHINING AND SAFETY
SHUTTING DOWN A CNC MACHINE
Emergency Stop Switch
Parking Machine Slides
Setting the Control System
Turning the Power Off
EQUIPMENT MAINTENANCE
.Vorking Environment
Tees of Pallets
-‘ogramming Commands .
– 5 et Changing Program Structure
-ORIZONTAL BORING MILL .
47 – WRITING A CNC PROGRAM
=ROGRAM WRITING
legibility of Handwriting
Programming Forms
lonfusing Characters
PROGRAM OUTPUT FORMATTING .
-ONG PROGRAMS
^’ogram Length Reduction
Vemory Mode and Tape Mode
51 – INTERFACING TO DEVICES 465
48 – PROGRAM DOCUMENTS 447 RS-232C INTERFACE
PUNCHED TAPE
Tape Reader and Puncher
Leader and Trailer
Tape Identification
Non-printable Characters
Storage and Handling
DISTRIBUTED NUMERICAL CONTROL .
TERMINOLOGY OF COMMUNICATIONS
Baud Rate
Parity
Data Bits
Start and Stop Bits
DATA SETTING
CONNECTING CABLES
Null Modem
Cabling for Fanuc and PC
465
466
DATA FILES
“OGRAMDOCUMENTATION .
External Documentation
“ternal Documentation
“’:gram Description
SE’UP AND TOOLING SHEETS .
Se:^o Sheet
~
:c ng Sheet
Ecordinate Sheet
DOCUMENTATION FILE FOLDER
centification Methods
C iterator ‘s Suggestions
r ng and Storage
-9 – PROGRAM VERIFICATION 453
EJECTION OF ERRORS 453 52 – MATH IN CNC PROGRAMMING 471
e.entive Measures 453
:’rective Measures BASIC ELEMENTS
Arithmetic and Algebra
Order of Calculations
GEOMETRY
Circle
PI Constant
Circumference of a Circle
Length of Arc
Quadrants
POLYGONS
TAPERS
Taper Definition
Taper Per Foot
Taper Ratio
Taper Calculations – English Units .
Taper Calculations – Metric Units .
CALCULATIONS OF TRIANGLES.
453 471
GRAPHIC VERIFICATION 471
-. OIDING ERRORS
;.'”.’axErrors
:g cal Errors
I3MMON PROGRAMMING ERRORS .
cram Input Errors 456
1= culation Errors .
– 2’dware Errors
cellaneous Errors
CNC MACHINING
CHINING A NEW PART
tup Integrity
:g’am Integrity
Table of Contents
2r s of Angles and Triangles .
– g~:Triangles
Simi ar Triangles
Sine – Cosine – Tangent
Inverse Trigonometric Functions
Degrees and Decimal Degrees .
Pythagorean Theorem
Solving Right Triangles
ADVANCED CALCULATIONS .
CONCLUSION
477 Hardware Specifications
Typical Hardware Requirements
Utilities and Special Features .
POST PROCESSORS
Customizing Post Processor .
IMPORTANT FEATURES .
Input from User
Machining Cycles
User Interface
CAD Interface
SUPPORT AND MANAGEMENT .
Training
System Management
Technical Support
THE END AND THE BEGINNING .
53 – CNC AND CAD/CAM 483 490
PROGRAMMING MANUALLY ?
CAM Software
Desktop Computer Programming
TOOL PATH GEOMETRY DEVELOPMENT .
TOOL PATH GENERATION
COMPLETE ENVIRONMENT
Multi Machine Support
Associative Operations
Job Setup
Tooling List and Job Comments
Connection Between Computers
Program Text Editor
Printing Capabilities
Pen Plotting
CAD Software Access
Support for Solids
Software Specifications
484 A – REFERENCE TABLES 491
Decimal Equivalents .
English Threads – UNC/UNF
Straight Pipe Taps NPS .
Taper Pipe Taps NPT .
Metric Coarse Threads .
Metric Fine Threads .
487Selective block skip .
Slash symbol
Used for program proving .
Used for trial cut .
Used with modal commands
Bolt hole circle pattern .
Boring operations
Backboring cycle 687
Block tools
Boring tools
Precision boring cycle 676.
Single point boring .
Tool shift
Boss milling
Index
Absolute data input . 70-73. 308, 430 2 0 3
Acceleration and deceleration
Additional axes .
Address format .
Air cutting
Alpha-numerical input
APC
Approach to the part
ATC 8. 95-96
Automatic corner break . 299
Automatic corner override
Automatic pallet change.
Automatic tool change .
ATC cycle
First tool in the spindle
Keeping track of tools .
Manual interference .
Maximum tool diameter
Maximum tool length .
Maximum tool weight .
No tool in the spindle .
Programming ATC .
Several tools .
Using a single tool .
Using oversize tools .
Auxiliary functions lock .
Axes and planes.
Axis orientation – milling .
Axis orientation – turning .
89
CAD/CAM
CAM software
Complete programming environment
Desktop computer programming .
General features
6eometry development
Postprocessors
Support and training
Toolpath generation
Calculation of triangles
Calculations
Calculator type input
Canned cycles
Cartesian coordinate system
Center cutting end mill
Centerline tools
Chamfering
Chamfer diameter
Character
Chuck functions
Circle cutting cycle
Circular interpolation
Arc center and radius
Arc center vectors
Arc cutting direction
Arc in planes
Arc programming
Blend radius
Boss milling
Circular motion direction
Elements of a circle
Feedrate for circular motion .
Full circle programming
Lead-in and lead-out path
Partial radius
Programming format
Quadrants
Radius programming
Start point and end point
Circumscribed circle
Clamp and unclamp functions
Climb milling
CNC machine tools
Four-axis lathe
Horizontal boring mill
Background edit 465 239. 271
Ball nose end mill
Barfeeder
B-axis
Bitwise input
Blend radius
Block
Block format
Block numbering .
Block numbers increment .
Block structure .
Conflicting words .
End-Of-Block (EOB) .
Sequence block
Single block
Status block
Block skip
Barfeeder application .
Numbered block skip .
Cycle start . 21.57. 170
Cycle time .
Horizontal machining center . 9
Lathe accessories
Lathe axes
Machine axes
Milling
Six-axis lathe
Three-axis lathe
Turning centers and lathes .
Two-axis lathe
Types of CNC lathes .
Typical specifications .
Vertical machining center
CNC machining
Alternate machine selection .
Machine shutdown .
New workpiece
Preventive maintenance .
Program i n t e g r i t y
Running the first part .
Safety issues
Setup integrity
Warm-up program
CNC programmer
Conflicting commands
Connection to external devices
Contouring
Continuous path
Equidistant path
Control system
Control panel
Defaults
Features
Memory capacity
Optional features
Conventional machining
Conventional milling.
Conversions
HP to kW
kW to HP
Coolant functions
Coordinate geometry .
Coordinate system rotation .
Counterboring
Countersinking
CSS
Cutter path determination.
Cutter radius offset.
Applying radius compensation .
Cutter direction change .
D amount setting.
Direction of motion .
Interference error.
Look-Ahead t y p e
Offset cancellation
Offset commands G40-G42
Practical example
Programming format .
Programming techniques .
Startup m e t h o d s
Tool nose radius offset
Toolpath center points
Types of offset
Cutting mode
Cutting tool animation
Datum shift 381-392
Cutter radius offset
Data setting .
Lathe offsets.
Program zero change .
Tool length offset.
Using MDI control mode
Using parameters
Work offsets.
Decimal point programming
Defaults
Delta increment
Departure position .
Depth of cut .
Descartes, Rene.
Diameter programming
Distance-To-Go
39 DNC 468
39 Drawing 31, 34
Changes and revisions .
Dimensioning methods .
Special instructions
Surface finish
Title block
Tolerances
Drawing dimension input .
Drilling operations .
Blind holes
Center drilling
Drill point length .
Effective drill diameter
Flat bottom drilling .
Indexable drills .
Multilevel drilling .
Nominal drill diameter.
Peck drilling
Reaming
Through holes
Web drilling
Drip-feeding
Dry run
Dummy tool
Dwell command .
As TAB alternative .
Dwell in number of revolutions
Dwelling axis
Long dwell time .
Minimum dwell .
Safety issues
Setting mode
Time selection .
Used in fixed cycles .
DXF files
Index 499
E G
GOO command
G01 command
G02-G03 commands
G04 command
G09 command
G10 data setting c o m m a n d
G12-G13 cycle
G15 command
G16 command
G17-G19 commands
G20 command
G21 command
G27 command
G28 command
G29 command
G30 command
G32 thread cutting command
G40 command
G41-G42 commands
G43 command
G44 command
G45-G48 commands
G49 command
G50 command
G50-G51 scaling commands
G52 command
G53 machine coordinates command .
G54.1 command
G54-G59 work offsets
G61 command
G62 command
G63 command
G64 command
G68-G69 commands
G70 cycle
G71-G73 cycles
G73 peck drilling cycle
G74 tapping cycle – left hand
G74-G75 lathe cycles
G76 precision boring cycle
G76 threading cycle
G80-G89 commands
G81 drilling cycle
G82 spot drilling cycle
G83 peck drilling cycle
G84 tapping cycle – right hand .
G85 boring cycle
G86 boring cycle
G87 backboring cycle
G88 boring cycle
G89 boring cycle
G90 absolute position command .
G90 lathe cycle
G91 incremental motion command
G92 position register command.
G92 threading cycle
G94 feedrate command
G94 lathe cycle
G95 feedrate command
G97 command
G98-G99 commands
Emergency stop . 21, 25
Empty tool .
End of block.
English units
EOB
Errors in programming
Calculation errors.
Hardware errors .
Input errors .
Logical errors
Miscellaneous errors
Syntax errors
E-switch .
Exact stop check
Exact stop check mode
Execution priority
Face milling 122, 227-234 79, 83, 113, 381
Cutter selection
Cutting considerations
Programming techniques .
Using position compensation .
Family part programming
Feedrate control
Circular cutting motion
Circular motion feedrate
Constant feedrate
E address in threading
Feed per minute
Feed per revolution
Feedhold
Feedrate override
Inverse time feedrate
Maximum feedrate
Selection
Fillet radius
Fixed cycles
Absolute and incremental applications
Basic format structure
Cancellation of a cycle
Cycle repetition
Detailed description
General rules
Initial level selection
L0 parameter
Plane selection
Programming format
R-level selection
Selection
Shift amount
Z-depth calculations
Format notation
Milling system format
Turning system f o r m a t
Gauge line . 131
G-c o d e s
Conflicting commands
Group numbers
Milling applications
Modal commands .
Turning applications
Types of G codes .
Using in a block .
With decimal point.
Gear ranges.
Geometry .
Geometry offset .
Graphic display .
Grooving and part-off
Corner groove
Grooving applications
Grooving dimensions
Multiple grooves .
Part-off .
Precision groove .
Simple groove .
Keyboard
L-address
Lathe cycles
Contour finishing cycle
Face cutting cycle
Multiple repetitive cycles .
P and Q blocks .
Pattern repeating cycle .
Principle of cycles
Profile cutting cycle .
Straight cutting cycle .
Lathe offsets .
Master tool setup
Multiple offsets .
Offset change
Offset e n t r y
Offsets and tool motion .
Lathe program format .
Least increment .
Linear interpolation
Cutting feedrate .
Multiaxis motion .
Programming format .
Single axis motion
Start and end of motion .
Live tooling
Local coordinate system
Handle 21-22
Helical milling
Helical interpolation .
Helix
Ramping
Thread milling
Thread milling example
Hockey stick motion
Home position
Horizontal machining centers
MOO function 56
M01 function
M02 program end function
M03 function
M04 function
M05 function
M06 function
M07 function
M08 function
M09 function
M10-M11 functions
M12-M13 functions
M15-M16 functions
M17-M18 functions
Ml9 function
M21-M22 functions
M23-M24 thread finishing functions
M30 program end function
M41-M44 functions
M48-M49 functions
IGES files 33
Incremental data input .
Indexing axis .
Indexing table .
Initial level selection
In-process gauging .
Input of dimensions .
Input format .
Zero suppression .
Inscribed circle .
Interfacing to devices 465-470
Connecting cables
Data setting .
DNC . 468 411
Punched tape 466
RS-232C interface .
Terminology of communications
Intermediate point .
Inverse time feedrate.
. 60.357
465, 467. 469 58
469 298
151 92
87Index 501
Mirror image . 393-398
Control setting .
Lathe applications
Programmable setting.
Programming functions
Miscellaneous functions
Application in a block
Description
Machine related functions .
Program related functions .
Special MDI functions .
Modal commands .
M-S-T lock
Multilevel drilling
Multiple repetitive cycles .
M60 function 60.439
M71-M72 function
M73-M74 functions
M88-M89 functions
M98-M99 subprogram functions .
Machinability rating
Machine accessories.
Machine coordinate system .
Machine geometry
Machine lock
Machine warm-up
Machine zero
Absolute and incremental mode
Intermediate point
Machine zero return .
Primary machine zero .
Program commands .
Return from machine zero .
Secondary machine zero .
Zero position check .
Machine zero return
Machining a workpiece
Machining cycles
Machining holes
Drilling
Hole enlargement .
Lathe applications
Peck drilling
Reaming
Single point boring .
Tapping
Tooling selection
Web drilling
Machining sequence
Manual absolute
Manual data input
Manual programming
Material specifications .
Math in programming .
Calculations of triangles .
Circle elements
Order of calculations .
M-codes
Machine related
MDI functions
M-function duration
Milling applications
Program related
Turning applications
Numerical control . 1-6
Advantages
Definition .
Hardwired controls
Softwired controls
Offsets . 298.315
Operation panel .
Optional stop
Orthographic orientation
Overtravel
Pallet c h a n g e r 429. 437
Pallet types
Parameters.
Parsons. John
Part catcher or unloader .
Part complexity .
Part reference point .
Part setup
Setup sheet .
Part-off
Parts counter .
Pattern of holes
Angular row hole pattern .
Arc hole pattern .
Bolt hole circle pattern
Corner pattern .
Grid pattern .
Random hole pattern .
Straight row hole pattern .
MDI , 26, 389 1
Memory capacity 24 414
Messages in a program .
Methods sheet .
Metric units.
Milling – G-codes.
Milling – M-codes
Milling operations
Direction of cut .
End mills
Peripheral milling .
Slots and pockets
Speeds and feeds
Stock removal .
Width and depth of cut
Minimum axis increment .
Lathes . 112
Machining centers
Selection methods
Programming formats
Format notation .
Word address format
Programming procedure
Programming terms .
Pull-Out finger .
Punched tape .
Pythagorean Theorem
Typical patterns . 217
Peck drilling
Percent sign
Peripheral spindle speed .
PI constant
Planes
Absence of axis data .
Circular interpolation in planes
Cutter radius offset
Definition
Fixed cycles
Machining in planes .
Mathematical planes .
Selection of planes .
Pocket milling
Circular pocket cycles .
Circular pockets .
Rectangular pockets .
Point of origin
Point-to-point machining.
Polar coordinate system .
Position compensation .
Incremental mode
Motion length calculation .
Programming commands .
Z-axis
Position register commands .
Definition
Lathes
Milling
Turning
Z-axis setting
Post p r o c e s s i n g
Power rating
Preparatory commands
Process sheet
Program
Program changes.
Program comments
Program end
Program header .
Program length reduction .
Program structure .
Program documents
Documentation file folder .
Documenting a program
Setup sheet
Tooling sheet
Program identification
Program name
Program number .
Program planning .
Program stop
Program verification.
Avoidance of errors .
Detection of errors .
Graphic method .
Input errors
Thread cutting .
Program writing
Confusing characters .
Long programs .
Output formatting
Programming forms .
Program zero
Quadrants 16, 236
Quality in CNC programming 40
Radius programming 240
Rapid positioning .
Approach to the part .
Hockey stick motion .
Motion formulas .
Reduction of rapid rate.
Tool path motion .
Real number system .
Reaming operations
Recess programming .
Rectangular coordinate system
Reference points .
Fixed point
Flexible point.
Machine zero .
Machine zero (home) .
Part reference point .
Reference point groups .
Tool reference point .
Register commands.
Return to machine zero .
Rigid tapping
R-level selection .
Roughing and finishing .
RS-232C interface .
Safe block . 65
Safety in CNC work .
Scaling function
G50-G51 commands
Scaling center .
Scaling factor
442 6
445 405-408
443 405
442 406
16. 109, 273 . 406Index 503
Target position .
Technological decisions .
Thread milling .
Example
Simulation method .
Tapered thread .
Threading
Block-by-block threading .
Depth of thread .
Forms of thread .
G76 cycle
Hand of thread .
Infeed methods .
Lead error
Maximum feedrate .
Multistart threads
Pitch vs. lead
Program testing .
Retract from thread .
Single point threading.
Speeds and feeds
Tapered thread .
Terminology
Thread forms
Thread recutting .
Threading process
Threading to a shoulder .
Tooling reference.
Tool function
Chip-to-chip time .
Lathes
Machining centers.
Tool indexing – lathes .
Tool length offset .
Cancellation
Change of offset .
Datum shift
Distance-To-Go calculation
G43-G44 difference .
Horizontal application.
Offset commands
Used with G54-59
Used with G92 .
Tool length setup .
O f f-m a c h i n e
Offset register .
O n-m a c h i n e
Preset tool length.
Using master tool
Tool magazine.
Tool memory type
Fixed type .
Random memory type .
Tool nose radius offset .
Change of motion direction
Radius offset commands
R-settmg
Tool tip orientation .
T-setting
Tool number registration .
Tool offset registers.
Geometry offset .
Wear offset
Tool position setting
Tool setup groups .
Screen display 21 . 39, 159
Sequence block
Sequence return
SETTINGS screen
Setup sheet
Similar triangles
Single block
Slash symbol
Slot drill
Slots and pockets
Speeds and feeds
Spherical end mill
Spindle control
Constant surface speed
Empty spindle
Maximum spindle speed setting.
Spindle rotation
Spindle speed – CSS
Spindle speed – RPM
Startup
Spindle functions
Spindle orientation
Spindle speed formulas
English version
Metric version
Spindle speed override
Spindle stop
Spotfacing
Status block
Stock allowance
Stock removal
Stored stroke limits
Subprograms
100 000 000 hole grid.
Development strategies .
Grooving applications
Identification
M98-M99 functions
Multi-level nesting
Numbering methods
Protected subprograms ,
Repetition
Subprogram call
Subprogram end
Using B-axis
Symbols in programming .
Tailstock functions . 410 266
Taper programming
Tapers
Tapping
Check list
Pipe taps
Speeds and feeds
Tap chamfer geometry
Tap flute geometry .
Tap geometry
Tapping mode.
Tapping on lathes.
Web drilling 208
Word address format.
Multiple addresses
Order of words in block .
Word
Work area
Work coordinate system.
Work offsets
Additional work offsets .
Common offset (COM)
Datum shift
Defaults
External offset (EXT) .
G54-G59 commands .
Horizontal machine application
Lathe applications
Startup
Work areas available .
Work offset change .
Z-axis application.
Work sketch
Center line tooling 1 1 6
External tooling .
Internal tooling .
Tooling selection.
Tooling sheet .
Trial cut .
Trigonometric table .
Trigonometry .
Turning – G-codes
Turning – M-codes .
Turning and boring .
Turning tools .
Turret indexing .
U/W commands 160 40
Undercut programming 304
w
Z-axis neglect . 28
W-axis . 10
Wear offset
Adjustment
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