G and M code definitions

Anyone have a complete list of G and M codes that sheetcam/Langmuir is using in this postprocessor?

G and M codes are standard in the industry.
search the web and you will find some great resources.
I just created a thread for people to post G code shortcuts…hopefully people will post some information there to help us all.
Here is a website I just found that is useful

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I’ve been programming CNC mills and lathes for 30 years there’s code in here that is not standard. They’re probably what’s refered to as user-defined codes. These codes may be common to the plasma table industry but I’m not familiar with them. For instance G38.2 I believe believe it was. I’m thinking this has to do with their torch height control parameters. there’s like 8 or 10 lines of code that keep repeating throughout the programs. Some of that was what I was curious about.

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G38.2 is for probing on an axis. In this case it is probing on the Z axis. The Z axis is slowly lowered until the ‘probe’ (which is system specific) senses contact with the material and, when it does, the motion is stopped. At that point the Z value would be zeroed (or set to some consistent over travel value) and then the torch is moved to a new Z height (typically the pierce height) and cutting can begin. This is usually done before every pierce in case the material is warped or the table isn’t level, etc.

In my experience, G codes for any system are ‘similar’, but I’d never call it a ‘standard’ as the definitions are not guided by any standards authority. De facto standard in some cases, but even there there are variations.

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Sheetcam is looking for.
a crossfire pro/firecontrol post processor, im trying to find same because it seems to not generate a valid code file without it, or am i missing something?

https://www.langmuirsystems.com/downloads
Look under post processors…

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I asked too soon, i answered my own question, bu thankyou i hope it helps someone else out here.

What about H1 I am working a program to cut interior and limited perimeter cuts from bar stock off 2 known datum corners set on the machine 2.00X and .00Y .Currently found to load the .dfx into sheet cam I have been leaving a perimeter of the stock in the .dxf so when it drops it into fire control my datum’s are already set. Iif I cut an edge next to my datum I put a 1/4" piece of stock in , jog the machine 1/4" manually and re zero so I don’t perish my datum corner edge. All that being said In sheet can I have been running a perimeter cut layer operation after all my needed cuts and watch the machine and pause before it tries to cut perimeter. I had some thoughts of just eliminating part of the G code in notepad related to firing the torch for perimeter so we could walk away and not be watching to pause and cancel. Any thought s on that ?. Seems I need a cut profile or some small geometry at my 00 to get my g-code tap files to drop in clean in sheet cam followed fire control. If I do NOT make a operation on perimeter the G code and fire control sets datum as basically geometry to cut and holes edges etc will be on your datum VS the fake edge of stock programmed into a exterior cut that will not actually be cut. I can play with it. I maybe generate the code and delete the H1 command in note pad seems to me H1 is torch on H0 is torch off. maybe just eliminate H1 and H0- or maybe only H1 is only needed, I am tempted to try it. Ken

The H commands are THC on and off. M3 is torch on. M5 is Torch off.

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Thanks so maybe delete H and M commands? Or just truncate the g code after it makes the last cut and moves to next position? Not sure if that will end clean in fire control . Maybe leave the last command in so fire control ends properly? maybe I can handle this in sheet cam to not need to post process in note pad. maybe my operation for perimeter cut can be somehow programmed not to cut but still be part of the file import the perimeter to set my datum?

Have you tried moving your perimeter cut to another layer and not creating an operation for that layer? That may preserve your origin and still just cut the interior features.

If that doesn’t work, create an operation for that layer and uncheck that operation before post processing.

DS,
Yes tried that but once that is post processed in sheet cam it removes any geometry related to outer layer any not used operations. So basically Fire control treats 00 as the 1st start point or maximum XY line to be cut ignoring where the 00 perimeter was since its absent from the G code it seems. I think I need to leave it in there as a path but just dump the THC and Fire torch commands.H and M ? let it dry run the perimeter if we don;'t want to pause and or kill it. it might not be bad to have that in the end as a no cut as in the dry run test initially you can make sure the stock is as it should be in the machine , potentially move that no cut operation 1st watch it trace your perimeter with no cut than cut the interior, repeats are just put stock in hit go to work zero and start .

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