G-code: Difference between revisions

Browse history interactively

← Previous edit

Content deleted Content added

VisualWikitext

Revision as of 08:32, 1 August 2023 edit Thumperward (talk \| contribs) Administrators 123,444 edits WP:NOTMANUAL ← Previous edit		Latest revision as of 06:53, 28 June 2025 edit undo OsFish (talk \| contribs) Extended confirmed users 2,063 edits m Reverted 1 edit by Natalielaurend (talk) to last revision by Alexander Davronov Tags: Twinkle Undo
(23 intermediate revisions by 18 users not shown)
Line 2: {{other uses\|G-code (disambiguation)\|G programming language (disambiguation)}} {{redirect\|RS-274\|the photoplotter format\|Gerber format}} {{More footnotes needed\|date=January 2025}} {{Ambox \| name = G-code \| subst = <includeonly>{{subst:substcheck}}</includeonly> \| issue = This article may require restoring an older revision. \| talk = RfC:_Partially_Reversing_Thumperward's_deletions \| date = May 13, 2025 }} {{Infobox programming language \| name = G-code Line 10 ⟶ 19: \| developer = [[Electronic Industries Alliance\|Electronic Industries Association]] (RS-274), [[International Organization for Standardization]] (ISO-6983) \| implementations = Numerous; mainly [[Siemens]] Sinumerik, [[FANUC]], [[Haas Automation\|Haas]], [[Heidenhain]], [[Yamazaki Mazak Corporation\|Mazak]], [[Okuma Corporation\|Okuma]] \| dialects = \| influenced by = \| influenced = \| programming language = \| platform = \| operating system = \| license = \| website = \| wikibooks = }} '''G-code''' (abbreviation for '''geometric code'''; also called<ref>{{cite tech report \|editor1-last=Barkmeyer \|editor1-first=Edward J. \|editor2-last=Hopp \|editor2-first=Theodore H. \|editor3-last=Michael J. \|editor3-first=Pratt \|editor4-last=Gaylen R. \|editor4-first=Rinaudot \|title=Background Study: Requisite Elements, Rationale, and Technology Overview for the Systems Integration for Manufacturing Applications (SIMA) Program \|date=1995 \|publisher=NIST Technical Series Publications \|___location=Gaithersburg, MD, USA \|pages=45 \|edition=NIST Interagency/Internal Report (NISTIR) 5662 \|url=https://nvlpubs.nist.gov/nistpubs/Legacy/IR/nistir5662.pdf}}</ref> '''RS-274''',<ref>{{cite book \|title=EIA Standard RS-274-D Interchangeable Variable Block Data Format for Positioning, Contouring, and Contouring/Positioning Numerically Controlled Machines \|date=February 1979 \|publisher=Electronic Industries Association \|___location=2001 Eye Street, NW, Washington, D.C. 20006 \|url=https://search.worldcat.org/de/title/11135300 \|ref=RS-274-D}}</ref> standardized today in '''ISO 6983-1'''<ref>{{cite tech report \|editor1-last=Technical Committee ISO/TC 184/SC 1 \|title=ISO 6983-1:2009 Automation systems and integration — Numerical control of machines — Program format and definitions of address words; Part 1: Data format for positioning, line motion and contouring control systems \|date=December 2009 \|publisher=International Standards Organization \|___location=Geneva, Switzerland \|url=https://www.iso.org/standard/34608.html \|ref=ISO 6983:2009}}</ref>) is the most widely used [[computer numerical control]] (CNC) and [[3D printing]] [[programming language]]. It is used mainly in [[computer-aided manufacturing]] to control automated [[machine tool]]s, as well as for [[Slicer (3D printing)\|3D-printer slicer applications]]. G-code has many variants. '''G-code''' (also '''RS-274''') is the most widely used [[computer numerical control]] (CNC) and [[3D printing]] [[programming language]]. It is used mainly in [[computer-aided manufacturing]] to control automated [[machine tool]]s, as well as for [[Slicer (3D printing)\|3D-printer slicer applications]]. The ''G'' stands for geometry. G-code has many variants. G-code instructions are provided to a [[Programmable logic controller\|machine controller]] (industrial computer) that tells the motors where to move, how fast to move, and what path to follow. The two most common situations are that, within a machine tool such as a [[Metal lathe\|lathe]] or [[Milling (machining)\|mill]], a [[cutting tool (machining)\|cutting tool]] is moved according to these instructions through a toolpath cutting away material to leave only the finished workpiece and/or an unfinished workpiece is precisely positioned in any of up to nine axes<ref>Karlo Apro (2008). ''[https://books.google.com/books?id=Ws228Aht0bcC Secrets of 5-Axis Machining]''. Industrial Press Inc. {{ISBN\|0-8311-3375-9}}.</ref> around the three dimensions relative to a toolpath and, either or both can move relative to each other. The same concept also extends to noncutting tools such as [[Forming (metalworking)\|forming]] or [[Burnishing (metal)\|burnishing]] tools, [[Gerber format\|photoplotting]], additive methods such as [[3D printing]], and measuring instruments. == History == ~~==Background and implementations==~~ The first implementation of a numerical control programming language was developed at the [[MIT Servomechanisms Laboratory]] in the 1950s. In the decades that followed, many implementations were developed by numerous organizations, both commercial and noncommercial. Elements of G-code had often been used in these implementations.<ref>{{cite book \| last=Xu \| first=Xun \| date=2009 \| url=https://www.google.com/books/edition/Integrating_Advanced_Computer_Aided_Desi/habcATPQWJ4C \| title=Integrating Advanced Computer-aided Design, Manufacturing, and Numerical Control: Principles and Implementations \| publisher=Information Science Reference \| page=166 \| isbn=9781599047164 \| via=Google Books}}</ref><ref>{{cite book \| last=Harik \| first=Ramy \| author2=Thorsten Wuest \| date=2019 \| url=https://www.google.com/books/edition/Introduction_to_Advanced_Manufacturing/O3h0EAAAQBAJ \| title=Introduction to Advanced Manufacturing \| publisher=SAE International \| page=116 \| isbn=9780768090963 \| via=Google Books}}</ref> The first [[Technical standard\|standardized]] version of G-code used in the United States, ''RS-274'', was published in 1963 by the [[Electronic Industries Alliance]] (EIA; then known as Electronic Industries Association).<ref>{{cite book \| last=Evans \| first=John M., Jr. \| date=1976 \| url=https://www.govinfo.gov/content/pkg/GOVPUB-C13-2ef4aaa5a150eedcb85a1e6985e90bfa/pdf/GOVPUB-C13-2ef4aaa5a150eedcb85a1e6985e90bfa.pdf \| title=National Bureau of Standards Information Report (NBSIR) 76-1094 (R): Standards for Computer Aided Manufacturing \| publisher=National Bureau of Standards \| page=43}}</ref> In 1974, EIA approved ''RS-274-C'', which merged ''RS-273'' (variable block for positioning and straight cut) and ''RS-274-B'' (variable block for contouring and contouring/positioning). A final revision of ''RS-274'' was approved in 1979, as ''RS-274-D''.<ref>{{cite journal \| last=Schenck \| first=John P. \| date=January 1, 1998 \| url=https://link.gale.com/apps/doc/A20429590/GPS?sid=wikipedia \| title=Understanding common CNC protocols \| work=Wood & Wood Products \| publisher=Vance Publishing \| volume=103 \| issue=1 \| page=43 \| via=Gale}}</ref><ref>{{citation\| title = EIA Standard RS-274-D Interchangeable Variable Block Data Format for Positioning, Contouring, and Contouring/Positioning Numerically Controlled Machines \|publisher = Electronic Industries Association \|___location= Washington D.C. \|date=February 1979}}</ref> In other countries, the standard ''[[International Organization for Standardization\|ISO]] 6983'' (finalized in 1982) is often used, but many European countries use other standards.<ref>{{cite book \| last=Stark \| first=J. \| author2=V. K. Nguyen \| date=2009 \| url=https://www.google.com/books/edition/Advanced_Design_and_Manufacturing_Based/RIgLRe12RD4C \| chapter=STEP-compliant CNC Systems, Present and Future Directions \| title=Advanced Design and Manufacturing Based on STEP \| editor-last=Xu \| editor-first=Xun \| editor2=Andrew Yeh Ching Nee \| publisher=Springer London \| page=216 \| isbn=9781848827394 \| via=Google Books}}</ref> For example, ''[[Deutsches Institut für Normung\|DIN]] 66025'' is used in Germany, and PN-73M-55256 and PN-93/M-55251 were formerly used in Poland. The first implementation of a numerical control programming language was developed at the [[MIT Servomechanisms Laboratory]] in the 1950s. In the decades that followed, many implementations were developed by numerous organizations, both commercial and noncommercial. Elements of G-code had often been used in these implementations.<ref>{{cite book \| last=Xu \| first=Xun \| date=2009 \| url=https://books.google.com/books?id=habcATPQWJ4C \| title=Integrating Advanced Computer-aided Design, Manufacturing, and Numerical Control: Principles and Implementations \| publisher=Information Science Reference \| page=166 \| isbn=978-1-59904-716-4 \| via=Google Books}}</ref><ref>{{cite book \| last=Harik \| first=Ramy \| author2=Thorsten Wuest \| date=2019 \| url=https://books.google.com/books?id=O3h0EAAAQBAJ \| title=Introduction to Advanced Manufacturing \| publisher=SAE International \| page=116 \| isbn=978-0-7680-9096-3 \| via=Google Books}}</ref> The first [[Technical standard\|standardized]] version of G-code used in the United States, ''RS-274'', was published in 1963 by the [[Electronic Industries Alliance]] (EIA; then known as Electronic Industries Association).<ref>{{cite book \| last=Evans \| first=John M. Jr. \| date=1976 \| url=https://www.govinfo.gov/content/pkg/GOVPUB-C13-2ef4aaa5a150eedcb85a1e6985e90bfa/pdf/GOVPUB-C13-2ef4aaa5a150eedcb85a1e6985e90bfa.pdf \| title=National Bureau of Standards Information Report (NBSIR) 76-1094 (R): Standards for Computer Aided Manufacturing \| publisher=National Bureau of Standards \| page=43}}</ref> In 1974, EIA approved ''RS-274-C'', which merged ''RS-273'' (variable block for positioning and straight cut) and ''RS-274-B'' (variable block for contouring and contouring/positioning). A final revision of ''RS-274'' was approved in 1979, as ''RS-274-D''.<ref>{{cite journal \| last=Schenck \| first=John P. \| date=January 1, 1998 \| url=https://link.gale.com/apps/doc/A20429590/GPS?sid=wikipedia \| title=Understanding common CNC protocols \| journal=Wood & Wood Products \| publisher=Vance Publishing \| volume=103 \| issue=1 \| page=43 \| via=Gale}}</ref><ref>{{citation\| title = EIA Standard RS-274-D Interchangeable Variable Block Data Format for Positioning, Contouring, and Contouring/Positioning Numerically Controlled Machines \|publisher = Electronic Industries Association \|___location= Washington D.C. \|date=February 1979}}</ref> In other countries, the standard ''[[International Organization for Standardization\|ISO]] 6983'' (finalized in 1982) is often used, but many European countries use other standards.<ref>{{cite book \| last=Stark \| first=J. \| author2=V. K. Nguyen \| date=2009 \| url=https://books.google.com/books?id=RIgLRe12RD4C \| chapter=STEP-compliant CNC Systems, Present and Future Directions \| title=Advanced Design and Manufacturing Based on STEP \| editor-last=Xu \| editor-first=Xun \| editor2=Andrew Yeh Ching Nee \| publisher=Springer London \| page=216 \| isbn=978-1-84882-739-4 \| via=Google Books}}</ref> For example, ''[[Deutsches Institut für Normung\|DIN]] 66025'' is used in Germany, and PN-73M-55256 and PN-93/M-55251 were formerly used in Poland. Extensions and variations have been added independently by control manufacturers and machine tool manufacturers, and operators of a specific controller must be aware of the differences between each manufacturer's product. During the 1970s through 1990s, many CNC machine tool builders attempted to overcome compatibility difficulties by standardizing on machine tool controllers built by [[Fanuc]]. [[Siemens]] was another market dominator in CNC controls, especially in Europe. In the 2010s, controller differences and incompatibility were mitigated with the widespread adoption of CAD/CAM applications that were capable of outputting machine operations in the appropriate G-code for a specific machine through a software tool called a post-processor (sometimes shortened to just a "post"). One standardized version of G-code, known as ''BCL'' (Binary Cutter Language), is used only on very few machines. Developed at MIT, BCL was developed to control CNC machines in terms of straight lines and arcs.<ref>{{Cite book\|url=https://books.google.com/books?id=GE8vBQAAQBAJ&q=binary+cutter+language+gcode&pg=PA321\|title=Information Technology Standards : Quest for the Common Byte.\|last=Martin.\|first=Libicki\|date=1995\|publisher=Elsevier Science\|isbn=9781483292489\|___location=Burlington\|pages=321\|oclc=895436474}}</ref> == Syntax == During the 1970s through 1990s, many CNC machine tool builders attempted to overcome compatibility difficulties by standardizing on machine tool controllers built by [[Fanuc]]. [[Siemens]] was another market dominator in CNC controls, especially in Europe. In the 2010s, controller differences and incompatibility are not as troublesome because machining operations are usually developed with CAD/CAM applications that can output the appropriate G-code for a specific machine through a software tool called a post-processor (sometimes shortened to just a "post"). G-code began as a limited language that lacked constructs such as loops, conditional operators, and programmer-declared variables with [[Natural language\|natural]]-word-including names (or the expressions in which to use them). It was unable to encode logic but was just a way to "connect the dots" where the programmer figured out many of the dots' locations longhand. The latest implementations of G-code include macro language capabilities somewhat closer to a [[high-level programming language]]. Additionally, all primary manufacturers (e.g., Fanuc, Siemens, [[Heidenhain]]) provide access to [[programmable logic controller]] (PLC) data, such as axis positioning data and tool data,<ref>{{cite web \|archive-date=2014-05-03 \|url=http://www.machinetoolhelp.com/Applications/macro/system_variables.html \|title=Fanuc macro system variables \|access-date=2014-06-30 \|archive-url=https://web.archive.org/web/20140503030834/http://www.machinetoolhelp.com/Applications/macro/system_variables.html }}</ref> via variables used by NC programs. These constructs make it easier to develop automation applications. Some CNC machines use "conversational" programming, which is a [[wizard (software)\|wizard]]-like programming mode that either hides G-code or completely bypasses the use of G-code. Some popular examples are Okuma's Advanced One Touch (AOT), Southwestern Industries' ProtoTRAK, Mazak's Mazatrol, Hurco's Ultimax and Winmax, Haas' Intuitive Programming System (IPS), and Mori Seiki's CAPS conversational software. == Extensions and variations == G-code began as a limited language that lacked constructs such as loops, conditional operators, and programmer-declared variables with [[Natural language\|natural]]-word-including names (or the expressions in which to use them). It was unable to encode logic but was just a way to "connect the dots" where the programmer figured out many of the dots' locations longhand. The latest implementations of G-code include macro language capabilities somewhat closer to a [[high-level programming language]]. Additionally, all primary manufacturers (e.g., Fanuc, Siemens, [[Heidenhain]]) provide access to [[programmable logic controller]] (PLC) data, such as axis positioning data and tool data,<ref>{{cite web \|url-status=dead \|archive-date=2014-05-03 \|url=http://www.machinetoolhelp.com/Applications/macro/system_variables.html \|title=Fanuc macro system variables \|access-date=2014-06-30 \|archive-url=https://web.archive.org/web/20140503030834/http://www.machinetoolhelp.com/Applications/macro/system_variables.html }}</ref> via variables used by NC programs. These constructs make it easier to develop automation applications. Extensions and variations have been added independently by control manufacturers and machine tool manufacturers, and operators of a specific controller must be aware of the differences between each manufacturer's product. ~~==Programming environments==~~ ~~{{Original research section\|date=January 2016}}~~ G-code's programming environments have evolved in parallel with those of general programming—from the earliest environments (e.g., writing a program with a pencil, typing it into a tape puncher) to the latest environments that combine CAD ([[computer-aided design]]), CAM ([[computer-aided manufacturing]]), and richly featured G-code editors. (G-code editors are analogous to [[XML editor]]s, using colors and indents semantically [plus other features] to aid the user in ways that basic [[text editor]]s can't. CAM packages are analogous to [[integrated development environment\|IDEs]] in general programming.) One standardized version of G-code, known as ''BCL'' (Binary Cutter Language), is used only on very few machines. Developed at MIT, BCL was developed to control CNC machines in terms of straight lines and arcs.<ref>{{Cite book\|url=https://books.google.com/books?id=GE8vBQAAQBAJ&q=binary+cutter+language+gcode&pg=PA321\|title=Information Technology Standards: Quest for the Common Byte.\|last=Martin.\|first=Libicki\|date=1995\|publisher=Elsevier Science\|isbn=978-1-4832-9248-9\|___location=Burlington\|page=321\|oclc=895436474}}</ref> ~~Two high-level paradigm shifts have been toward:~~ Some CNC machines use "conversational" programming, which is a [[wizard (software)\|wizard]]-like programming mode that either hides G-code or completely bypasses the use of G-code. Some popular examples are Okuma's Advanced One Touch (AOT), Southwestern Industries' ProtoTRAK, Mazak's Mazatrol, Hurco's Ultimax and Winmax, Haas' Intuitive Programming System (IPS), and Mori Seiki's CAPS conversational software. # abandoning "manual programming" (with nothing but a pencil or text editor and a human mind) for [[:Category:Computer-aided manufacturing software\|CAM software]] systems that generate G-code automatically via postprocessors (analogous to the development of [[Visual programming language\|visual]] techniques in general programming) # abandoning hardcoded constructs for parametric ones (analogous to the difference in general programming between hardcoding a constant into an equation versus declaring it a variable and assigning new values to it at will; and to the [[object-oriented programming\|object-oriented]] approach in general). == See also == Macro (parametric) CNC programming uses human-friendly variable names, [[relational operator]]s, and loop structures, much as general programming does, to capture information and logic with machine-readable semantics. Whereas older manual CNC programming could only describe particular instances of parts in numeric form, macro programming describes abstractions that can easily apply in a wide variety of instances. ~~The tendency is comparable to a computer programming evolution from [[low-level programming language]]s to [[High-level programming language\|high-level ones]].{{Citation needed\|date=January 2022}}~~ [[STEP-NC]] reflects the same theme, which can be viewed as yet another step along a path that started with the development of machine tools, jigs and fixtures, and numerical control, which all sought to "build the skill into the tool." Recent developments of G-code and STEP-NC aim to build the information and semantics into the tool. This idea is not new; from the beginning of numerical control, the concept of an end-to-end CAD/CAM environment was the goal of such early technologies as [[DAC-1]] and [[APT (programming language)\|APT]]. Those efforts were fine for huge corporations like GM and Boeing. However, [[small and medium enterprises]] went through an era of simpler implementations of NC, with relatively primitive "connect-the-dots" G-code and manual programming until CAD/CAM improved and disseminated throughout the industry. Any machine tool with a great number of axes, spindles, and tool stations is difficult to program well manually. It has been done over the years, but not easily. This challenge has existed for decades in CNC screw machine and rotary transfer programming, and it now also arises with today's newer machining centers called "turn-mills", "mill-turns", "multitasking machines", and "multifunction machines". Now that [[Computer-aided technologies\|CAD/CAM]] systems are widely used, CNC programming (such as with G-code) requires CAD/CAM (as opposed to manual programming) to be practical and competitive in the market segments these classes of machines serve.<ref name="MMS_2010-12-20_CAM_Sys">{{Citation \|last=MMS editorial staff \|date=2010-12-20 \|title=CAM system simplifies Swiss-type lathe programming \|journal=Modern Machine Shop \|volume=83 \|issue=8 [2011 Jan] \|pages=100–105 \|url=http://www.mmsonline.com/articles/cam-system-simplifies-swiss-type-lathe-programming}} ''Online ahead of print.''</ref> As Smid says, "Combine all these axes with some additional features, and the amount of knowledge required to succeed is quite overwhelming, to say the least."<ref name="Smid2008p457">{{Harvnb\|Smid\|2008\|p=457}}.</ref> At the same time, however, programmers still must thoroughly understand the principles of manual programming and must think critically and second-guess some aspects of the software's decisions. Since about the mid-2000s, it seems "the death of manual programming" (that is, of writing lines of G-code without CAD/CAM assistance) may be approaching. However, it is currently only in ''some'' contexts that manual programming is obsolete. Plenty of CAM programming takes place nowadays among people who are rusty on, or incapable of, manual programming—but it is not true that ''all'' CNC programming can be done, or done ''as well'' or ''as efficiently'', without knowing G-code.<ref name="Lynch_MMS_2010-01-18">{{Citation \|last=Lynch \|first=Mike \|date=2010-01-18 \|title=When programmers should know G code \|journal=Modern Machine Shop \|edition=online \|url=http://www.mmsonline.com/columns/when-programmers-should-know-g-code \|postscript=.}}</ref><ref name="Lynch_MMS_2011-10-19">{{Citation \|last=Lynch \|first=Mike \|date=2011-10-19 \|title=Five CNC myths and misconceptions [CNC Tech Talk column, Editor's Commentary] \|journal=Modern Machine Shop \|edition=online \|url=http://www.mmsonline.com/columns/five-cnc-myths-and-misconceptions \|postscript=. \|access-date=2011-11-22 \|archive-url=https://web.archive.org/web/20170527082655/http://www.mmsonline.com/columns/five-cnc-myths-and-misconceptions \|archive-date=2017-05-27 \|url-status=dead }}</ref> Tailoring and refining the CNC program at the machine is an area of practice where it can be easier or more efficient to edit the G-code directly rather than editing the CAM toolpaths and re-post-processing the program. Making a living cutting parts on computer-controlled machines has been made both easier and harder by CAD/CAM software. Efficiently written G-code can be a challenge for CAM software. Ideally, a CNC machinist should know both manual and CAM programming well so that the benefits of both brute-force CAM and elegant hand programming can be used where needed. <!-- True, and the references from Mike Lynch above touch on the same concept. --> Many older machines were built with limited [[computer memory]] at a time when memory was very expensive; 32K was considered plenty of room for manual programs whereas modern CAM software can post gigabytes of code. CAM excels at getting a program out quickly that may take up more machine memory and take longer to run. This often makes it quite valuable to machining a low quantity of parts. But a balance must be struck between the time it takes to create a program and the time the program takes to machine a part. It has become easier and faster to make just a few parts on the newer machines with much memory. This has taken its toll on both hand programmers and manual machinists. Given natural [[turnover (employment)\|turnover]] into retirement, it is not realistic to expect to maintain a large pool of operators who are highly skilled in manual programming when their commercial environment ''mostly'' can no longer provide the countless hours of deep experience it took to build that skill; and yet the loss of this experience base can be appreciated, and there are times when such a pool is sorely missed because some CNC or [[3D printing]] runs still cannot be optimized without such skill. ~~==Abbreviations used by programmers and operators==~~ ~~This list is only a selection and, except for a few key terms, mostly avoids duplicating the many abbreviations listed at [[engineering drawing abbreviations and symbols]].~~ ~~<!--~~ ~~\| valign="top" \| {{Visible anchor\|}} \|\| expansion \|\|  ~~ \|- ~~-->~~ ~~{\| class="wikitable"~~ \|- ~~! Abbreviation !! Expansion !! Corollary info~~ \|- ~~\| valign="top" \| {{Visible anchor\|APC}} \|\| automatic pallet changer \|\| See [[#M60\|M60]].~~ \|- ~~\| valign="top" \| {{Visible anchor\|ATC}} \|\| automatic tool changer \|\| See [[#M06\|M06]].~~ \|- ~~\| valign="top" \| {{Visible anchor\|CAD/CAM}} \|\| [[computer-aided design]] and [[computer-aided manufacturing]] \|\|  ~~ \|- ~~\| valign="top" \| {{Visible anchor\|CCW}} \|\| [[clockwise\|counterclockwise]] \|\| See [[#M04\|M04]].~~ \|- ~~\| valign="top" \| {{Visible anchor\|CNC}} \|\| [[numerical control\|computerized numerical control]] \|\|  ~~ \|- ~~\| valign="top" \| {{Visible anchor\|CRC}} \|\| [[cutter ___location\|cutter radius compensation]] \|\| See also [[#G40\|G40]], [[#G41\|G41]], and [[#G42\|G42]].~~ \|- \| valign="top" \| {{Visible anchor\|CS}} \|\| cutting speed \|\| Referring to [[speeds and feeds#Cutting speed\|cutting speed (surface speed)]] in [[surface feet per minute]] (sfm, sfpm) or meters per minute (m/min). \|- ~~\| valign="top" \| {{Visible anchor\|CSS}} \|\| constant surface speed \|\| See [[#G96\|G96]] for explanation.~~ \|- ~~\| valign="top" \| {{Visible anchor\|CW}} \|\| [[clockwise]] \|\| See [[#M03\|M03]].~~ \|- \| valign="top" \| {{Visible anchor\|DNC}} \|\| [[direct numerical control\|direct numerical control ''or'' distributed numerical control]] \|\|  Sometimes referred to as "Drip Feeding" or "Drip Numerical Control" due to the fact that a file can be "drip" fed to a machine, line by line, over a serial protocol such as RS232. DNC allows machines with limited amounts of memory to run larger files. \|- ~~\|DOC~~ ~~\|depth of cut~~ ~~\|Refers to how deep (in the Z direction) a given cut will be~~ \|- \| valign="top" \| {{Visible anchor\|EOB}} \|\| end of block \|\| The G-code synonym of ''end of line (EOL)''. A [[control character]] equating to [[newline]]. In many implementations of G-code (as also, more generally, in many [[programming language]]s), a [[semicolon]] (;) is synonymous with EOB. In some controls (especially older ones) it must be explicitly typed and displayed. Other software treats it as a nonprinting/nondisplaying character, much like [[word processor\|word processing apps]] treat the [[pilcrow]] (¶). \|- ~~\| valign="top" \| {{Visible anchor\|E-stop}} \|\| [[emergency stop#Industrial equipment\|emergency stop]] \|\|  ~~ \|- \| valign="top" \| {{Visible anchor\|EXT}} \|\| external \|\| On the operation panel, one of the positions of the mode switch is "external", sometimes abbreviated as "EXT", referring to any external source of data, such as tape or DNC, in contrast to the [[computer memory]] that is built into the CNC itself. \|- ~~\| valign="top" \| {{Visible anchor\|FIM}} \|\| [[total indicator reading\|full indicator movement]] \|\|  ~~ \|- ~~\| valign="top" \| {{Visible anchor\|FPM}} \|\| feet per minute \|\| See [[#SFM\|SFM]].~~ \|- ~~\| valign="top" \| {{Visible anchor\|HBM}} \|\| horizontal boring mill \|\| A type of machine tool that specializes in boring, typically large holes in large workpieces.~~ \|- ~~\| valign="top" \| {{Visible anchor\|HMC}} \|\| [[milling machine\|horizontal machining center]] \|\|  ~~ \|- \| valign="top" \| {{Visible anchor\|HSM}} \|\| high speed machining \|\| Refers to machining at [[speeds and feeds\|speeds]] considered high by traditional standards. Usually achieved with special geared-up spindle attachments or with the latest high-rev spindles. On modern machines HSM refers to a cutting strategy with a light, constant chip load and high feed rate, usually at or near the full depth of cut.<ref>{{Cite web\|url=https://www.mmsonline.com/articles/tool-path-strategies-for-high-speed-machining\|title=Tool Path Strategies For High-Speed Machining\|last=Marinac\|first=Dan\|website=www.mmsonline.com\|date=15 February 2000 \|access-date=2018-03-06}}</ref> \|- \| valign="top" \| {{Visible anchor\|HSS}} \|\| [[high-speed steel]] \|\| A type of [[tool steel]] used to make cutters. Still widely used today (versatile, affordable, capable) although carbide and others continue to erode its share of commercial applications due to their higher rate of material removal. \|- ~~\| valign="top" \| {{Visible anchor\|in}} \|\| [[inch]](es) \|\|  ~~ \|- ~~\| valign="top" \| {{Visible anchor\|IPF}} \|\| inches per flute \|\| Also known as ''chip load'' or [[#IPT\|IPT]]. See [[#F\|F address]] and [[speeds and feeds#Feed rate\|feed rate]].~~ \|- ~~\| valign="top" \| {{Visible anchor\|IPM}} \|\| inches per minute \|\| See [[#F\|F address]] and [[speeds and feeds#Feed rate\|feed rate]].~~ \|- ~~\| valign="top" \| {{Visible anchor\|IPR}} \|\| inches per revolution \|\| See [[#F\|F address]] and [[speeds and feeds#Feed rate\|feed rate]].~~ \|- ~~\| valign="top" \| {{Visible anchor\|IPT}} \|\| inches per tooth \|\| Also known as ''chip load'' or [[#IPF\|IPF]]. See [[#F\|F address]] and [[speeds and feeds#Feed rate\|feed rate]].~~ \|- ~~\| valign="top" \| {{Visible anchor\|MDI}} \|\| manual data input \|\| A mode of operation in which the operator can type in lines of program (blocks of code) and then execute them by pushing cycle start.~~ \|- \| valign="top" \| {{Visible anchor\|MEM}} \|\| memory \|\| On the operation panel, one of the positions of the mode switch is "memory", sometimes abbreviated as "MEM", referring to the [[computer memory]] that is built into the CNC itself, in contrast to any external source of data, such as tape or DNC. \|- \| valign="top" \| {{Visible anchor\|MFO}} \|\| manual feed rate override \|\| The MFO dial or buttons allow the CNC operator or machinist to multiply the programmed feed value by any percentage typically between 10% and 200%. This is to allow fine-tuning of [[speeds and feeds]] to minimize [[machining vibrations\|chatter]], improve [[surface finish]], lengthen tool life, and so on. The [[#SSO\|SSO]] and MFO features can be locked out for various reasons, such as for synchronization of speed and feed in threading, or even to prevent "soldiering"/"dogging" by operators. {{Anchor\|Arbitrary-speed_threading}} On some newer controls, the synchronization of speed and feed in threading is sophisticated enough that SSO and MFO can be available during threading, which helps with fine-tuning speeds and feeds to reduce chatter on the threads or in repair work involving the picking up of existing threads.<ref name="Korn_2014-05-06">{{Citation \|last=Korn \|first=Derek \|date=2014-05-06 \|title=What is arbitrary speed threading? \|journal=[[Modern Machine Shop]] \|url=http://www.mmsonline.com/blog/post/what-is-arbitrary-speed-threading \|postscript=.}}</ref> \|- ~~\| valign="top" \| {{Visible anchor\|mm}} \|\| [[millimetre]](s) \|\|  ~~ \|- ~~\| valign="top" \| {{Visible anchor\|MPG}} \|\| [[manual pulse generator]] \|\| Referring to the handle (handwheel) (each click of the handle generates one pulse of servo input)~~ \|- ~~\| valign="top" \| {{Visible anchor\|NC}} \|\| [[numerical control]] \|\|  ~~ \|- ~~\| valign="top" \| {{Visible anchor\|OSS}} \|\| oriented spindle stop \|\| See comments at [[#M19\|M19]].~~ \|- ~~\| valign="top" \| {{Visible anchor\|SFM}} \|\| [[surface feet per minute]] \|\| See also [[speeds and feeds]] and [[#G96\|G96]].~~ \|- ~~\| valign="top" \| {{Visible anchor\|SFPM}} \|\| [[surface feet per minute]] \|\| See also [[speeds and feeds]] and [[#G96\|G96]].~~ \|- ~~\| valign="top" \| {{Visible anchor\|SPT}} \|\| [[Threading (manufacturing)#Single-point threading\|single-point threading]] \|\|  ~~ \|- \| valign="top" \| {{Visible anchor\|SSO}} \|\| spindle speed override \|\| The SSO dial or buttons allow the CNC operator or machinist to multiply the programmed speed value by any percentage typically between 10% and 200%. This is to allow fine-tuning of [[speeds and feeds]] to minimize [[machining vibrations\|chatter]], improve [[surface finish]], lengthen tool life, and so on. The SSO and [[#MFO\|MFO]] features can be locked out for various reasons, such as for synchronization of speed and feed in threading, or even to prevent "[[Scientific_management#Soldiering\|soldiering"/"dogging"]] by operators. On some newer controls, the synchronization of speed and feed in threading is sophisticated enough that SSO and MFO can be available during threading, which helps with fine-tuning speeds and feeds to reduce chatter on the threads or in repair work involving the picking up of existing threads.<ref name="Korn_2014-05-06"/> \|- ~~\| valign="top" \| {{Visible anchor\|TC}} or T/C \|\| tool change, tool changer \|\|  See [[#M06\|M06]].~~ \|- ~~\| valign="top" \| {{Visible anchor\|TIR}} \|\| [[total indicator reading]] \|\|  ~~ \|- ~~\| valign="top" \| {{Visible anchor\|TPI}} \|\| [[screw thread#Lead, pitch, and starts\|threads per inch]] \|\|  ~~ \|- ~~\| valign="top" \| {{Visible anchor\|USB}} \|\| [[Universal Serial Bus]] \|\| One type of connection for data transfer~~ \|- ~~\| valign="top" \| {{Visible anchor\|VMC}} \|\| [[milling machine\|vertical machining center]] \|\|  ~~ \|- \| valign="top" \| {{Visible anchor\|VTL}} \|\| [[turret lathe#Vertical turret lathes\|vertical turret lathe]] \|\| A type of machine tool that is essentially a lathe with its Z-axis turned vertical, allowing the faceplate to sit like a large turntable. The VTL concept overlaps with the vertical boring mill concept. \|- \|} ~~==See also==~~ * [[3D printing]] * [[Canned cycle]] * [[Direct Numerical Control]] * [[LinuxCNC]] - a free CNC software with many resources for G-code documentation * [[LinuxCNC]] * [[Drill file (disambiguation)\|Drill file]] * [[List of computer-aided manufacturing software]] * [[HP-GL]] * [[STL (file format)]] * [[Slicer (3D printing)]] ~~===Extended developments===~~ [[Direct Numerical Control]] (DNC) [[STEP-NC]] [[MTConnect]] ~~===Similar concepts===~~ [[Gerber file]] ~~===Concerns during application===~~ [[Cutter ___location]], cutter compensation, offset parameters [[Coordinate system]]s ~~Industrial robot languages~~ * [[RAPID]] * [[KUKA Robot Language]] == References == {{Reflist~~\|30em~~}} == Bibliography == * {{MachinerysHandbook25e}} * {{Smid2008}} * {{Smid2010}} * {{Citation \|last=Smid \|first=Peter \|year=2004 \|title=Fanuc CNC Custom Macros \|publisher=Industrial Press \|url=https://books.google.com/books?id=YKvH-zYd3VwC&pg=PR11 \|isbn=978-~~0831131579~~0-8311-3157-9 \|postscript=.}} == External links == * [http://carlsonmfg.com/cnc-g-code-m-code-programming CNC G-Code and M-Code Programming] * {{Citation \|last1=Kramer \|first1=T. R. \|last2=Proctor \|first2=F. M. \|last3=Messina \|first3=E. R. \|title=The NIST RS274NGC Interpreter – Version 3 \|date=1 Aug 2000 \|id=NISTIR 6556 \|journal=[[NIST]] \|url=https://www.nist.gov/manuscript-publication-search.cfm?pub_id=823374 \|ref=none}} * http://museum.mit.edu/150/86 {{Webarchive\|url=https://web.archive.org/web/20160319102859/http://museum.mit.edu/150/86 \|date=2016-03-19 }} Has several links (including history of MIT Servo Lab) * [http://reprap.org/wiki/G-code Complete list of G-code used by most 3D printers] at reprap.org * [http://www.cnccookbook.com/CCCNCGCodeList.html Fanuc and Haas G-code Reference] * [http://www.cnccookbook.com/CCCNCGCodeCourse.htm Fanuc and Haas G-code Tutorial] Line 207 ⟶ 80: {{Metalworking navbox\|machopen}} ~~{{DEFAULTSORT:G-Code}}~~ [[Category:Computer-aided engineering]] [[Category:Domain-specific programming languages]]