CNC-Master: NC code, G-code & CNC knowledge on CNC-Master

The 3D part file: STEP and Parasolid X_T

Mon, 01 Jan 0001 00:00:00 +0000

The 3D part, meaning the 3D file, is the interface between CAD and CAM. It is used to exchange data between CAD and CAM and also to exchange information between different CAD systems. Two formats have become widely established for this: STEP as a vendor-neutral standard and X_T through the widespread use of the Parasolid kernel.

STEP / STP file

The STEP format (Standard for the Exchange of Product Data) is an industrial file format for exchanging 3D models and product information between different CAD systems. It has been standardized by the International Organization for Standardization (ISO) and is based on a neutral, platform-independent data model.

Cartesian coordinate system

Mon, 01 Jan 0001 00:00:00 +0000

The Cartesian coordinate system, named after the French mathematician René Descartes, is used to describe points in a plane or in space unambiguously. In CNC technology it is the foundation of every position: each point the tool moves to is defined by coordinates.

Two dimensions: X and Y

In the two-dimensional coordinate system, two axes are perpendicular to each other: the X-axis runs horizontally, the Y-axis vertically. The point where the two axes intersect is called the origin and carries the coordinate pair (0, 0).

Control flow basics: how a program makes decisions

Mon, 01 Jan 0001 00:00:00 +0000

A G-code program runs from top to bottom, block by block. Every value is written in the program: X50, Z-12, F200. If the part changes, the program has to be changed.

A macro program can do more. It stores values under a name, calculates new values from them, checks conditions and jumps to another part of the program depending on the result. These tools are called control flow, because they control in which order the blocks are executed.

Definition: grammar of the NCX language

Mon, 01 Jan 0001 00:00:00 +0000

The NCX language is defined as a formal grammar in Backus-Naur form (BNF). An NC program consists of blocks (lines) made up of cells of the form [KEYWORD:ADDRESS=VALUE].

Grammar

<program> ::= ( <block> <new-line> )+
<new-line> ::= "\n"
<block> ::= <cell>+
<cell> ::= "[" <content> "]"
<content> ::= <function> "=" <target>
<function> ::= <text> | <text> ":" <address>
<address> ::= <text>
<target> ::= <value> | <value> "," <target>
<value> ::= <text> | <decimal> | <integer>
<decimal> ::= <integer> "." <digits>
<integer> ::= <digits> | "-" <digits>
<digits> ::= <digit>+
<digit> ::= "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"
<text> ::= <character>+
<character> ::= "A" ... "Z" | <digit> | "_" | "+"

The productions in detail

<program>: A program consists of one or more blocks, each terminated by a new line.
<block>: A block is a sequence of one or more cells and corresponds to one program line.
<cell>: The cell is the basic unit of a program. Each cell consists of content enclosed in square brackets […].
<content>: The content of a cell is made up of a function and a target, separated by an equals sign =.
<function>: The function specifies which action the cell performs. It consists either of text alone or of text followed by a colon : and an address.
<address>: The address is optional and is only used when the function requires one. It consists of text.
<target>: The target specifies what the function is applied to: a single value or a comma-separated list of values (e.g. INTERPO=ARC,CCW).
<value>: A value can be text, a decimal number or an integer.
<decimal>: A decimal number consists of an integer part and a fractional part, separated by a decimal point . (e.g. -22.543).
<integer>: An integer is a positive or negative whole number without decimal places; negative numbers start with a minus sign -.
<digits>: A sequence of one or more digits.
<text>: Text is a sequence of one or more characters.
<character>: A single character is an uppercase letter A–Z, a digit, the underscore _ or the plus sign + (e.g. in WORKPLANE=XY+Z). Spaces are not permitted.

Example

A block, here a clockwise arc with a center point, consists of several cells:

Fanuc G-codes: reference table

Mon, 01 Jan 0001 00:00:00 +0000

This reference lists the G-codes of the Fanuc control. The first table shows the most important everyday commands, the second the complete list from G00 to G113. The functions actually available depend on the control model and its options.

To learn how to read and write the work offsets G54 to G59 via macro variables, see Work offset parameters.

Essential G-codes

Code	Description
G00	Positioning (rapid traverse)
G01	Linear interpolation (cutting feed)
G02	Circular interpolation clockwise or helical interpolation clockwise
G03	Circular interpolation counterclockwise or helical interpolation counterclockwise
G17	XpYp plane selection
G18	ZpXp plane selection
G19	YpZp plane selection
G68	Start coordinate system rotation or activate three-dimensional coordinate conversion
G69	Cancel coordinate system rotation or deactivate three-dimensional coordinate conversion
G80	Canned cycle cancel
G81	Drilling cycle or spot drilling cycle
G83	Deep-hole drilling cycle
G84	Tapping cycle
G90	Absolute programming
G91	Incremental programming
G94	Feed per minute
G95	Feed per revolution
G96	Constant surface speed control
G97	Constant surface speed control cancel

Full reference

Code	Description
G00	Positioning (rapid traverse)
G01	Linear interpolation (cutting feed)
G02	Circular interpolation clockwise or helical interpolation clockwise
G03	Circular interpolation counterclockwise or helical interpolation counterclockwise
G02.2	Involute interpolation clockwise
G03.2	Involute interpolation counterclockwise
G02.3	Exponential interpolation clockwise
G03.3	Exponential interpolation counterclockwise
G02.4	Three-dimensional coordinate transformation clockwise
G03.4	Three-dimensional coordinate transformation counterclockwise
G04	Dwell
G05	AI contour control (command compatible with high-precision contour control)
G05.1	AI contour control / nano smoothing / smooth interpolation
G05.4	HRV3/4 on/off
G06.2	NURBS interpolation
G07	Interpolation with a virtual axis
G07.1	Cylindrical interpolation (G107)
G08	AI contour control (command compatible with advanced look-ahead control)
G09	Exact stop
G10	Data input by program
G10.6	Tool retraction and recovery
G10.9	Programmable switching of the diameter/radius specification
G11	Data input by program mode cancel
G12.1	Polar coordinate interpolation mode
G13.1	Polar coordinate interpolation mode cancel
G15	Polar coordinate command cancel
G16	Polar coordinate command
G17	XpYp plane selection
G18	ZpXp plane selection
G19	YpZp plane selection
G20	Input in inches (G70)
G21	Input in mm (G71)
G22	Soft limit monitoring on
G23	Soft limit monitoring off
G25	Spindle speed deviation monitoring off
G26	Spindle speed deviation monitoring on
G27	Reference point check
G28	Automatic return to reference point
G29	Return from reference point
G30	Move to the 2nd, 3rd and 4th reference points
G30.1	Move to the shiftable reference point
G31	Skip function
G31.8	Skip for EGB axis
G33	Thread cutting
G34	Thread cutting with variable lead
G35	Circular thread cutting clockwise
G36	Circular thread cutting counterclockwise
G37	Automatic tool length measurement
G38	Cutter or tool nose radius compensation: preserve vector
G39	Cutter or tool nose radius compensation: corner circular interpolation
G40	Cutter or tool nose radius compensation cancel; three-dimensional tool radius compensation cancel
G41	Cutter or tool nose radius compensation left; three-dimensional tool radius compensation left
G41.2	Cutter compensation for 5-axis machining: left (type 1)
G41.3	Cutter compensation for 5-axis machining (leading-edge compensation)
G41.4	Tool radius compensation for 5-axis machining: left (type 1, FS16i-compatible command)
G41.5	Tool radius compensation for 5-axis machining: left (type 1)
G41.6	Tool radius compensation for 5-axis machining: left (type 2)
G42	Cutter or tool nose radius compensation right; three-dimensional tool radius compensation right
G42.2	Cutter compensation for 5-axis machining: right (type 1)
G42.4	Tool radius compensation for 5-axis machining: right (type 1)
G42.5	Tool radius compensation for 5-axis machining: right (type 1)
G42.6	Tool radius compensation for 5-axis machining: right (type 2)
G40.1	Normal direction control mode cancel
G41.1	Normal direction control on: left
G42.1	Normal direction control on: right
G43	Tool length compensation +
G44	Tool length compensation −
G43.1	Tool length compensation in the tool axis direction
G43.4	Tool center point control (type 1)
G43.5	Tool center point control (type 2)
G45	Increase tool compensation amount
G46	Decrease tool compensation amount
G47	Double increase of tool compensation amount
G48	Double decrease of tool compensation amount
G49	Tool length compensation cancel (G49.1)
G50	Scaling cancel
G51	Scaling
G50.1	Programmable mirror image cancel
G51.1	Programmable mirror image
G50.2	Polygon turning cancel
G51.2	Polygon turning
G52	Local coordinate system setting
G53	Machine coordinate system setting
G53.1	Tool axis direction control
G54	Workpiece coordinate system 1 selection (G54.1)
G55	Workpiece coordinate system 2 selection
G56	Workpiece coordinate system 3 selection
G57	Workpiece coordinate system 4 selection
G58	Workpiece coordinate system 5 selection
G59	Workpiece coordinate system 6 selection
G60	Single-direction positioning
G61	Exact stop mode
G62	Automatic corner override
G63	Tapping mode
G64	Cutting mode
G65	Macro call
G66	Modal macro call A
G66.1	Modal macro call B
G67	Modal macro call A/B cancel
G68	Start coordinate system rotation or activate three-dimensional coordinate conversion
G69	Cancel coordinate system rotation or deactivate three-dimensional coordinate conversion
G68.2	Feature coordinate system selection
G72.1	Figure copying (rotational copy)
G72.2	Figure copying (linear copy)
G73	Deep-hole drilling cycle
G74	Left-hand tapping cycle
G76	Fine boring cycle
G80	Canned cycle cancel
G80.5	Electronic gearbox with 2 axis pairs: end of synchronization
G80.8	Electronic gearbox: end of synchronization
G81	Drilling cycle or spot drilling cycle
G81.1	Chopping (reciprocating axis motion)
G81.5	Electronic gearbox with 2 axis pairs: start of synchronization
G81.8	Electronic gearbox: start of synchronization
G82	Drilling cycle or counterboring cycle
G83	Deep-hole drilling cycle
G84	Tapping cycle
G84.2	Tapping cycle without floating tap holder (FS15 format)
G84.3	Left-hand tapping without floating tap holder (FS15 format)
G85	Boring cycle
G86	Boring cycle
G87	Back boring cycle
G88	Boring cycle
G89	Boring cycle
G90	Absolute programming
G91	Incremental programming
G91.1	Check of the maximum specified incremental amount
G92	Workpiece coordinate system setting or maximum spindle speed clamp
G92.1	Workpiece coordinate system preset
G93	Inverse-time feed
G94	Feed per minute
G95	Feed per revolution
G96	Constant surface speed control
G97	Constant surface speed control cancel
G98	Canned cycle: return to initial level
G99	Canned cycle: return to R point level
G107	Cylindrical interpolation
G112	Polar coordinate interpolation
G113	Polar coordinate interpolation cancel

Mazak G-codes: reference table

Mon, 01 Jan 0001 00:00:00 +0000

This reference lists the G-codes used in EIA/ISO programs on Mazatrol controls (Fusion 640M, Matrix, Matrix 2, SmoothG). Conversational Mazatrol programs do not use them. The available set depends on the control generation and the installed options. A G-code the control does not know, or one whose option is missing, stops the program with alarm 808.

The fixed cycles are described in detail on the page Fixed cycles.

Modal groups

Codes in group 00 act only in the block in which they are written. All other groups are modal. G-codes from different groups can share a block, and the control processes them in ascending group order. If two codes from the same group appear in one block, the last one is valid.

Sinumerik 840D G-codes: reference by group

Mon, 01 Jan 0001 00:00:00 +0000

On a Sinumerik control, G commands are organized in numbered G groups. Only one command per group can be written in a block. A command stays active until another command of the same group replaces it (modal), or it acts only in its own block (non-modal). Many groups contain keywords instead of G numbers, for example TRANS, BRISK or CUT2D.

This page lists the groups that matter for everyday milling and turning. Groups for punching, nibbling, grinding, spline transitions and OEM extensions are left out. The “Default” column shows the command that is active after power-on, reset or program end in the delivery state. The machine builder can change these defaults, so the actual state on a machine may differ.

Heidenhain M-codes: reference table

Mon, 01 Jan 0001 00:00:00 +0000

M-codes, called miscellaneous functions on Heidenhain controls, switch machine functions such as the spindle, coolant, and program run. Some of them are machine-dependent and defined by the machine tool builder; the manual of your specific TNC control describes their exact behavior.

Essential M-codes

These are the M-codes you will use most often in day-to-day work on a Heidenhain control.

Code	Description
M03	Spindle ON clockwise
M05	Spindle STOP
M08	Coolant ON
M09	Coolant OFF
M30	Same function as M02 (end of program)
M91	In the positioning block: coordinates refer to the machine zero point
M92	In the positioning block: coordinates refer to a position defined by the machine manufacturer, e.g. the tool change position
M94	Reduce the rotary axis display to a value below 360°
M99	Blockwise cycle call
M116	Feed rate for rotary axes in mm/min
M126	Shortest-path traverse of rotary axes
M128	Maintain the position of the tool tip when positioning tilting axes (TCPM)
M129	Reset M128
M130	In the positioning block: points refer to the untilted coordinate system
M136	Feed rate F in millimeters per spindle revolution
M137	Reset M136
M140	Retract from the contour in the tool axis direction
M150	Suppress limit switch message

Full reference

All M-codes at a glance, sorted by number.

Hurco M-codes: reference table

Mon, 01 Jan 0001 00:00:00 +0000

On Hurco machining centers, M-codes control the machine functions: spindle, coolant, tool changes, rotary axis clamping, probing, and laser functions. The basics of tool changes and spindle commands apply here just as on any other control.

Essential M-codes

Code	Function
M00	Program stop: stops the spindle, coolant, and program execution.
M01	Optional program stop, often used when the operator needs to re-clamp the workpiece.
M02	End of program: stops spindle, coolant, and axis feed.
M03	Starts the spindle clockwise.
M04	Starts the spindle counterclockwise.
M05	Turns off the spindle.
M06	Triggers an automatic tool change.
M08	Turns on coolant system 1.
M09	Turns off coolant systems 1 and 2.
M30	End of program: marks the end of the main program.
M98	Calls a subprogram.
M99	Return from a subprogram.

Example

T1 M06 ; load tool 1
S8000 M03 ; spindle clockwise, 8000 rpm
M08 ; coolant on
G01 X50 Y20 F500
M09 ; coolant off
M05 ; spindle off
M30 ; end of program

Reference

Code	Function
M00	Program stop: stops the spindle, coolant, and program execution.
M01	Optional program stop, often used when the operator needs to re-clamp the workpiece.
M02	End of program: stops spindle, coolant, and axis feed.
M03	Starts the spindle clockwise.
M04	Starts the spindle counterclockwise.
M05	Turns off the spindle.
M06	Triggers an automatic tool change.
M07	Turns on coolant system 2.
M08	Turns on coolant system 1.
M09	Turns off coolant systems 1 and 2.
M10	Turns on coolant systems 1 and 2.
M12	Clamps the C axis (rotary table).
M13	Unclamps the C axis (rotary table).
M20	Advances the indexer by one position.
M21	Starts the lubrication cycle.
M25	Retracts the Z axis to its home position (tool change position).
M26	Selects the workpiece probing signal.
M27	Selects the tool probing signal.
M29	Activates synchronous tapping.
M30	End of program: marks the end of the main program.
M32	Clamps the A axis (rotary table).
M33	Unclamps the A axis (rotary table).
M34	Clamps the B axis (rotary table).
M35	Unclamps the B axis (rotary table).
M36	Turns off the servo drives.
M38	Captures and sets the state of the laser “OK” signal.
M39	Captures and sets the state of the static laser signal.
M40	Captures and sets the state of the dynamic laser signal.
M41	Disables two-touch probing with G31.
M42	Enables automatic two-touch probing with G31: if the workpiece probe is triggered during the G31 move, it retracts automatically and probes a second time at reduced feed.
M43	Increases the purge air.
M44	Decreases the purge air.
M45	Opens the shutter.
M46	Closes the shutter.
M47	Turns on the laser transmitter.
M48	Turns off the laser transmitter.
M49	Turns on the laser receiver.
M50	Turns off the laser receiver.
M52	Activates auxiliary output 1.
M53	Activates auxiliary output 2.
M54	Activates auxiliary output 3.
M55	Activates auxiliary output 4.
M56	Rotates the pallet changer for a pallet change without confirmation.
M57	Rotates the pallet changer to pallet 1.
M58	Rotates the pallet changer to pallet 2.
M59	Starts the chip conveyor in forward direction.
M60	Starts the chip conveyor in reverse direction.
M61	Stops the chip conveyor.
M62	Deactivates auxiliary output 1.
M63	Deactivates auxiliary output 2.
M64	Deactivates auxiliary output 3.
M65	Deactivates auxiliary output 4.
M68	Activates flood coolant.
M69	Deactivates flood coolant.
M76	Normal A-axis operation (default setting).
M77	Reverses A-axis operation.
M78	Normal B-axis operation (default setting).
M79	Reverses B-axis operation.
M80	Positive C-axis rotation direction (default setting).
M81	Negative C-axis rotation direction.
M98	Calls a subprogram.
M99	Return from a subprogram.

Machine-dependent availability

Which M-codes are actually available depends on the machine model and its equipment, such as a pallet changer, rotary table, or laser measurement system. The documentation for your specific WinMax control is authoritative.

Okuma M-codes (turning): reference table

Mon, 01 Jan 0001 00:00:00 +0000

Okuma’s OSP control uses M-codes (miscellaneous functions) to switch machine functions such as the spindle, coolant, chuck, tailstock, and tool change. This reference lists the M-codes for Okuma lathes from M00 to M1255.

Machine-dependent assignment

The “Standard/Option” column shows whether a code is part of the base configuration or requires an optional machine function. Which codes are actually available depends on the model and equipment. When in doubt, your machine’s documentation applies.

CNC machine manufacturers: the big list

Mon, 01 Jan 0001 00:00:00 +0000

The number of CNC machine suppliers is usually underestimated. The following list is incomplete by design. It spans milling and turning machines, EDM, laser and waterjet systems, CNC routers and additive manufacturing. Use it when evaluating a new machine, or simply to get a feel for how broad the market really is.

Manufacturer	Website
3D SYSTEMS	de.3dsystems.com
ACCUTEX	www.accutex.com.tw
ACRA	acramachinery.com
ADVANCE CUTTING SYSTEMS	advancecutting.com
AKIRA SEIKI	www.akiraseiki.com
ALZMETALL	alzmetall.de
AMADA	www.amada.eu
AMERA SEIKI	www.ameraseikicnc.com
ANDERSON AMERICA	andersonamerica.com
AP LAZER	aplazer.com
ASSOCIATED PACIFIC	apmcorp.com
ATRUMP	www.atrump.com
AVID	www.avidcnc.com
AWEA	www.awea.com
AXIOM	www.axiomprecision.com
AXYZ	www.axyz.com
BAVELLONI	www.bavelloni.com
BIESSE	www.biesse.com
BIGLIA	www.bigliaspa.it
BOSS LASER	bosslaser.com
BRIDGEPORT	www.hardinge.com
BROTHER	machinetool.global.brother
BURNTABLES	www.burntables.com
C.R. ONSRUD	www.cronsrud.com
CHEVALIER	www.chevaliertw.com
CHIRON	chiron-group.com
CINCINNATI	cinmac.com
CITIZEN	cmj.citizen.co.jp
CLAUSING	clausing-industrial.com
CNC MASTERS	www.cncmasters.com
COBRA	www.cobracnc.com.br
COLCHESTER	www.colchester.co.uk
COLEX	www.colex.com
CONPROFE	www.conprofetech.cn
CORREA	www.nicolascorrea.com
COSINE	www.cosineadditive.com
DATRON	www.datron.com
DEPOMILL	www.depo-cnc.com
DIGITAL WOOD CARVER	www.digitalwoodcarver.com
DMG MORI	www.dmgmori.com
DMS	dmscncrouters.com
DOALL	www.doallsaws.com
DOOSAN	www.doosanmachinetools.com
EMCO	www.emco-world.com
ENSHU	www.enshu.co.jp
EOS	www.eos.info
EPILOG LASER	www.epiloglaser.ch
EUROTECH	eurotechelite.com
EXEL CNC AUTOMATION	www.exelcnc.com
FADAL	fadal.com
FANUC	www.fanuc.eu
FEELER	www.feeler.com
FEMCO	www.femcousa.com
FERMAT	www.fermatmachinery.com
FIDIA	www.fidia.it
FLOW	www.flowwaterjet.com
FMB	www.fmb-machinery.de
FPT	www.fptindustrie.com
FRYER	www.fryermachine.com
GANESH	www.ganeshcnc.com
GIDDINGS & LEWIS	www.fivesgroup.com
HAAS	www.haascnc.com
HACO	www.haco.com
HANWHA	www.hanwha-pm.com
HARDINGE	www.hardinge.com
HEDELIUS	www.hedelius.de
HELLER	www.heller.biz
HENDRICK	www.hendrickmanufacturing.com
HERMLE	www.hermle.de
HG TECH	www.hgtech-laser.com
HOMAG	www.homag.com
HONOR	www.honorseiki.com
HUAHUA	www.huahuacnc.com
HÜLLER HILLE	www.hueller-hille.com
HURCO	www.hurco.com
HWACHEON	www.hwacheon.com
HYUNDAI WIA	machine.hyundai-wia.com
IKEGAI	www.ikegai.co.jp
IMSA	www.imsaitaly.com
INDEX	www.index-group.com
JOHNFORD	www.johnford.com.tw
KAAST	www.kaast.de
KINGSTON	www.kingstonmachine.com
KITAKO	www.smd.co.jp
KITAMURA	www.kitamura-machinery.com
KIWA	www.kiwa-mc.co.jp
KNUTH	www.knuth.com
KOMO	komo.com
KONE	www.kone.com.br
LAGUNA	lagunatools.com
LEADWELL	www.leadwell.com.tw
LUCAS	lucasprecision.com
LVD STRIPPIT	www.lvdgroup.com
MAG	ffg-ea.com
MAKINO	www.makino.com
MATEC	www.matec.de
MATSUURA	www.matsuurausa.com
MAXMILL	maxmill-cnc.com
MAZAK	www.mazak.com
MIGHTY VIPER	www.mightyviper.com
MIKRON	www.mikron.com
MILLTRONICS	milltronics.com
MITSUI SEIKI	www.mitsuiseiki.com
MIYANO	www.citizenmachines.com
MOLLART	mollart.com
MORI SEIKI	dmgmori.com
MULTICAM	www.multicam.com
NAKAMURA TOME	www.nakamura-tome.com
NIIGATA	www.niigata.eu
OHIO TOOL WORKS	www.ohiotoolworks.com
OKAMOTO	www.okamotocorp.com
OKK	www.okkeurope.com
OKUMA	www.okuma.com
OMAX	www.omax.com
PARK INDUSTRIES	www.parkindustries.com
PEDDINGHAUS	www.peddinghaus.com
PIETRO CARNAGHI	www.pietrocarnaghi.it
PITTLER	www.dvs-technology.com
POLYGIM	www.polygim.com.tw
RAVELLI	ravelli.it
REIDEN	reiden.com
ROBOTEC	www.robotec-cnc.com
SAACKE	saacke-pforzheim.com
SAMAG	www.samag.de
SAMCHULLY	www.samchully.com
SAMSUNG	www.smecmachinetools.com
SHARP	sharp-industries.com
SHIBAURA MACHINE	shibaura-machine.com
SHOPSABRE	www.shopsabre.com
SHW	www.shw-wm.de
SIP	www.starrag.com
SMART	www.smartmachinetool.com
SNK	www.snkc.co.jp
SODICK	sodick.com
SORALUCE	www.soraluce.com
SPINNER	www.spinner.eu.com
STAR	starcnc.com
STRATASYS	www.stratasys.com
SUNNEN	www.sunnen.com
TAKAMAZ	www.takamaz.co.jp
TAKISAWA	www.takisawa.co.jp
TAKUMI	www.takumi.com.tw
TARUS	tarus.com
THERMWOOD	www.thermwood.com
TONGTAI	www.tongtai.com.tw
TORMACH	tormach.com
TOSHIBA	shibaura-machine.com
TOSHIBA SHIBAURA	shibaura-machine.com
TOYODA	www.toyoda.com
TRAK	www.southwesternindustries.com
TRAUB	www.index-group.com
TRUMPF	www.trumpf.com
TSUGAMI	www.tsugami.co.jp
VELOX	www.veloxcncrouters.com
VISION WIDE	www.visionwide-tech.com
W.F. WELLS	wfwells.com
WASINO	www.dmgmori.co.jp
WEEKE	www.homag.com
WEISSER	www.weisser-web.com
WFL	www.wfl.at
WILLEMIN	willemin-macodel.com
YAMA SEIKI	www.yamaseiki.com
YASDA	yasda.com
YCM	www.ycmcnc.com
YOU JI	www.youji.com
ZENBOT	www.zenbotcnc.com

Structure of an NC program

Mon, 01 Jan 0001 00:00:00 +0000

In most cases, NC code follows a clear structure, especially when it was generated by CAM software. Depending on the section, the program contains different information and instructions: from the program header through tool calls to the actual machining blocks.

The following graphic shows what such a structure looks like:

NC-code simulation: why it matters

Mon, 01 Jan 0001 00:00:00 +0000

NC-code simulation software verifies NC programs in a virtual environment before they run on the real CNC machine. Collisions and programming errors are caught before they can damage the machine, the tool, or the workpiece.

Why CAM simulation is not enough

The simulation built into a CAM system only shows the toolpaths computed by the machining algorithms. The final NC code, however, is generated by the postprocessor, and that is exactly where a potential source of error lies: the postprocessor can apply changes and mathematical operations to the NC code that are never shown in the CAM simulation and remain invisible to the user.

Heidenhain code numbers (TNC 530)

Mon, 01 Jan 0001 00:00:00 +0000

Code numbers work like passwords: entering them on the control unlocks additional settings and functions. The list below applies to the TNC 530 control generation.

For trained service personnel only

Code numbers unlock service-level functions of the TNC 530. Changes to machine parameters, the PLC program, or the kinematics can damage the machine and are intended exclusively for trained service personnel.

Building your own tilt cycle: rotation matrices in NC macros

Mon, 01 Jan 0001 00:00:00 +0000

On machines where a rotary/tilt table has been retrofitted, the control often provides no tilt cycle such as G68.2 or PLANE SPATIAL. This means that for every tilted position, a zero point has to be probed manually and entered into the offset table. The procedure is cumbersome and error-prone: setup time and scrap rates increase because a correction, at a compound angle for example, can only be made after machining.

Linear interpolation: G0 and G1

Mon, 01 Jan 0001 00:00:00 +0000

G0 and G1 are two fundamental G-codes in CNC programming that control the movement of the machine tool. They are like the basic directions that tell a driver where to go and how fast.

G0: rapid traverse

The G0 command, known as rapid traverse, is like a sprinter covering the distance between two points as fast as possible. With G0, the machine moves at maximum speed. The command is used to bring the tool to a new position without cutting any material.

Mazak M-codes: reference table

Mon, 01 Jan 0001 00:00:00 +0000

Mazatrol controls switch machine functions such as spindles, coolant, pallets and chucks with M-codes. This reference lists the common M-codes for Mazak machining centers and Integrex multitasking machines in EIA/ISO programs.

Machine-dependent assignment

Many M-codes are set by the machine builder per model. Some codes in this list are missing on a given machine, and others may be used for different functions. The codes for spindle 1 and 2, tailstock, steady rest and bar feeder only exist on machines with that equipment. When in doubt, the documentation of your machine applies.

Sinumerik 840D M-codes: reference table

Mon, 01 Jan 0001 00:00:00 +0000

M functions are auxiliary functions. The NC passes them to the PLC, and the PLC program switches the machine function. On a Sinumerik control only a small set of M functions is fixed by the control itself. All other numbers are free for the machine builder.

Machine-dependent assignment

Coolant, clamping, doors, chip conveyor and similar functions are defined by the machine builder. The same number can switch different functions on two machines. When in doubt, the documentation of your machine applies.

NC macros and computer code: a comparison with Python

Mon, 01 Jan 0001 00:00:00 +0000

NC macro languages are small programming languages. They were designed decades ago and look old-fashioned, but the ideas behind them are the same as in any modern language. This page puts NC macros next to Python, a language that is often used for teaching because it reads almost like English.

You do not need to install or learn Python. The comparison has two goals. If you have seen Python or a similar language before, you can transfer that knowledge directly. If not, the Python lines help to see the structure behind the cryptic NC syntax.

ModuleWorks: the components behind many CAM systems

Mon, 01 Jan 0001 00:00:00 +0000

ModuleWorks is one of the unsung heroes of the CAM world: few users have ever heard of the company, yet its software components power most CAM systems on the market. This look behind the scenes shows why that plays a decisive role when choosing a CAM system.

A note on perspective

This article is an opinion piece and reflects the author’s personal assessment.

Specification of the NCX elements

Mon, 01 Jan 0001 00:00:00 +0000

Each element of the NCX language is written as one cell of the form [KEYWORD:ADDRESS=VALUE]: the keyword, an optional address and the value. The following overview documents all elements with their addresses, values and examples; where available, the corresponding conventional G or M command is given as well. The underlying grammar is described in the Definition.

Program

`PROGRAM`: Program

Defines the header data of an NC program: name, unit of measurement and an optional comment.

Fanuc work offset parameters: G54–G59 via macro variables

Mon, 01 Jan 0001 00:00:00 +0000

On Fanuc controls, the work offsets G54 to G59 can be read and written through macro variables. The tables below list the variable numbers per axis; for the extended work offsets G54.1 P1 to P48, the variable number is calculated. For an overview of all G-codes, see the Fanuc G-code reference.

G54 to G59

G54

Variable number	Axis
#5221	X
#5222	Y
#5223	Z
#5224	4
#5225	5

G55

Variable number	Axis
#5241	X
#5242	Y
#5243	Z
#5244	4
#5245	5

G56

Variable number	Axis
#5261	X
#5262	Y
#5263	Z
#5264	4
#5265	5

G57

Variable number	Axis
#5281	X
#5282	Y
#5283	Z
#5284	4
#5285	5

G58

Variable number	Axis
#5301	X
#5302	Y
#5303	Z
#5304	4
#5305	5

G59

Variable number	Axis
#5321	X
#5322	Y
#5323	Z
#5324	4
#5325	5

G54.1 P1 to G54.1 P48

The workpiece zero point data for P1 to P48 is stored in the variable numbers #7001 to #7945. It is best to calculate the matching variable number:

CAM systems and vendors: overview

Mon, 01 Jan 0001 00:00:00 +0000

Here is a (non-exhaustive) overview of common CAM systems with a link to each vendor’s website.

Product	Vendor
AlphaCAM	alphacam.com
BobCAD-CAM	bobcad.com
CAMWorks	camworks.com
CATIA V5 Machining	3ds.com
Cimatron	cimatron.com
Creo CAM	ptc.com
Dolphin CAD/CAM	dolphincadcam.com
e-CAM	e-cam.it
EdgeCAM	edgecam.com
Esprit	espritcam.com
EUKLID CAD/CAM	euklid-cadcam.com
Exapt CAM	exapt.de
FeatureCAM	autodesk.com
Fikus Visualcam	metalcam.com
FreeCAD	freecad.org
Fusion 360	autodesk.com
Gibbs CAM	gibbscam.com
Go2CAM	go2cam.net
HSMWorks	autodesk.com
hyperMILL	openmind-tech.com
InventorCAM	solidcam.com
Mastercam	mastercam.com
NCG CAM	ncgcam.com
NX CAM	siemens.com
OPUS CAM	opus-cam.de
PEGASUS CAD-CAM	pegasuscadcam.com
PENTA-NC	penta-tec.com
PEPS	camtek.de
PowerMill	autodesk.com
ProfiCAM	coscom.de
SimplexCAM	simplexcam.ch
SmartCAM	smartcamcnc.com
SolidCAM	solidcam.com
SolidWorks CAM	solidworks.com
SprutCAM	sprutcam.com
SurfCAM	surfcam.com
SYMplus	cnc-keller.de
Tebis	tebis.com
TopSolid CAM	topsolid.com
VectorCAM	vectorcam.com
VISI CAD/CAM	mecadat.de
VisualCAD/CAM	mecsoft.com
WorkNC	worknc.com

Circular interpolation: G2 and G3

Mon, 01 Jan 0001 00:00:00 +0000

After G0 and G1 for straight movements come G2 and G3: the commands for circular interpolation. With them, the machine cuts or engraves circular paths: arcs and full circles.

G2: clockwise

The G2 command stands for clockwise circular interpolation (CW). The tool moves from the start point along a defined arc in a clockwise direction to the end point.

G3: counterclockwise

G3 is the counterpart: counterclockwise circular interpolation (CCW). The arc is programmed with the same parameters, just in the opposite direction of rotation.

Sinumerik 840D cycles: drilling, milling and turning

Mon, 01 Jan 0001 00:00:00 +0000

Sinumerik cycles are subprograms that are called with a parameter list, for example CYCLE83(…). The input screens of the control write the call with all parameters, but the call can also be typed by hand. The parameter order is fixed: an unused parameter keeps its comma, and parameters at the end of the list can be dropped.

The lists on this page are the classic parameter lists of the 840D. On an 840D sl with SINUMERIK Operate the cycle names are the same, but most cycles have additional parameters at the end of the list. A program written with the short list still runs, the missing parameters take their default values.

Examples: Fanuc G-code to NCX

Mon, 01 Jan 0001 00:00:00 +0000

The following examples show how typical Fanuc G-code blocks are converted into the NCX format, each with the source block and the corresponding NCX cells.

Not yet specified

The rows marked with * use radius programming as well as the extended cycle parameters CYCLE_DELAY, CYCLE_SURFACE_ALTITUDE and CYCLE_DEPTH_INCREMENT. These are not yet covered by the current specification. The language is still in development.

Fanuc Macro B: variables, IF, WHILE and G65 explained

Mon, 01 Jan 0001 00:00:00 +0000

Fanuc Custom Macro B, usually just called Macro B, is the macro language of Fanuc controls and of many controls that copy the Fanuc dialect. This page explains the parts you need for everyday work. The general ideas behind variables, conditions and loops are explained in Control flow basics.

Is Macro B available?

On older controls Macro B is an option. If the offset screen shows a page for macro variables, the function is installed. The available variable ranges and some details depend on the control generation and the machine builder’s settings. When in doubt, test with harmless values in MDI first.

Mazak fixed cycles: drilling, tapping, boring and turning

Mon, 01 Jan 0001 00:00:00 +0000

Mazak fixed cycles carry out positioning, drilling, tapping or boring with a single block. The G-numbers match the usual ISO assignment for the common cases (G81, G83, G84), but the boring cycles G75 to G79 and several addresses work differently from other controls. Programs moved from another machine should be checked cycle by cycle.

Block structure

G□□ X_ Y_ Z_ Q_ R_ P_ D_ K_ I_ J_(B_) E_ H_ F_ L_

The block has four parts: the cycle code, the hole position (X, Y), the machining data and the repeat count L. The hole position and L apply only to the current block. The machining data are modal and stay active for the following hole positions until the cycle is cancelled.

Tool change and spindle commands: T, M6, M3/M4/M5, S

Mon, 01 Jan 0001 00:00:00 +0000

In CNC programming, T, M and S commands control central functions of the machine: selecting and changing the tool, and switching the spindle on and off with the desired direction and speed.

Tool call with T and M6

The tool is called with the T command (e.g. T1, T2, etc.), which selects a specific tool from the tool magazine, comparable to a chef picking the right kitchen tool for a task. The M6 command then performs the actual tool change: the tool selected with T is loaded into the spindle.

CNC-Master: NC code, G-code & CNC knowledge on CNC-Master

The 3D part file: STEP and Parasolid X_T

STEP / STP file

Cartesian coordinate system

Two dimensions: X and Y

Control flow basics: how a program makes decisions

Definition: grammar of the NCX language

Grammar

The productions in detail

Example

Fanuc G-codes: reference table

Essential G-codes

Full reference

Mazak G-codes: reference table

Sinumerik 840D G-codes: reference by group

Heidenhain M-codes: reference table

Essential M-codes

Full reference

Hurco M-codes: reference table

Essential M-codes

Example

Reference

Okuma M-codes (turning): reference table

CNC machine manufacturers: the big list

Structure of an NC program

NC-code simulation: why it matters

Why CAM simulation is not enough

Heidenhain code numbers (TNC 530)

Building your own tilt cycle: rotation matrices in NC macros

Linear interpolation: G0 and G1

G0: rapid traverse

Mazak M-codes: reference table

Sinumerik 840D M-codes: reference table

NC macros and computer code: a comparison with Python

ModuleWorks: the components behind many CAM systems

Specification of the NCX elements

Program

PROGRAM: Program

Fanuc work offset parameters: G54–G59 via macro variables

G54 to G59

G54

G55

G56

G57

G58

G59

G54.1 P1 to G54.1 P48

CAM systems and vendors: overview

Circular interpolation: G2 and G3

G2: clockwise

G3: counterclockwise

Sinumerik 840D cycles: drilling, milling and turning

Examples: Fanuc G-code to NCX

Fanuc Macro B: variables, IF, WHILE and G65 explained

Mazak fixed cycles: drilling, tapping, boring and turning

Block structure

Tool change and spindle commands: T, M6, M3/M4/M5, S

Tool call with T and M6

`PROGRAM`: Program