Fanuc G71 G72 equivalent

I already know there is no G code in linuxcnc for accomplishing the same thing as a Fanuc lathe canned cycle. But the problem is almost all our shop programs have G71,G72 cycles. So my plan is creating a subroutine that does the same as the Fanuc canned cycles.

Anybody tried this before?

I would search the forum and mail list - I remember people working on something like this. (but it might be a different g code)

Chris M

ReinaldoP wrote: I already know there is no G code in linuxcnc for accomplishing the same thing as a Fanuc lathe canned cycle. But the problem is almost all our shop programs have G71,G72 cycles. So my plan is creating a subroutine that does the same as the Fanuc canned cycles.

There is (incomplete) work on adding this to LinuxCNC in this development branch:
github.com/LinuxCNC/linuxcnc/tree/BenPotter/G71

Alternatively the codes are implemented as a Python remap here:
github.com/LinuxCNC/linuxcnc/tree/andypugh/g71type2remap

The latter version does not do tool radius correction in the roughing cycles. It _ought_ to work on the finish pass.
(The reason to move the code into the main LinuxCNC C++ code is to use the already-existing compensation rather than re-code it in Python)

I wrote docs for the G71 cycle here:
github.com/LinuxCNC/linuxcnc/blob/22e10f...ughing-cycle-turning

It should be fairly easy to add the remap to your own installations, but it isn't 100% of all that the cycles should be.

Thanks Andy, Ill look into that. Ive been working with Linuxcnc for years now in our shop and this is going to be a lifesaver. I'm still running 2.6.7 with a modified gmoccapy gui so I'm hesitant on upgrading due to all the tweaks I've done thru the years with gmoccapy

The remap ought to work with 2.6.7

Are there any instructions on how to do a remap using these files? Also which files are needed for this?

github.com/LinuxCNC/linuxcnc/tree/andypugh/g71type2remap

Thank you,

Barry

G71 and G72 now exist built-in to Master:
linuxcnc.org/docs/master/html/gcode/g-code.html#gcode:g71-g72

And that version has different code-letter allocations.

So you have a choice of running the master (devlopment, unstable) version of LinuxCNC from the buildbot, or remapping your existing installation. (and then learning new letter allocations when 2.9 comes out)

To apply the remap, put the whole "python" folder from here in your config folder,
github.com/LinuxCNC/linuxcnc/tree/andypu...configs/sim/axis/g71
And then make these edits to your INI:
github.com/LinuxCNC/linuxcnc/blob/andypu...is/g71/lathe.ini#L39

(ie, work lines 39 to 44 into your own INI in the RS274NGC section)

1st, thank you for the quick reply. You saved me many many hours of struggling and I greatly appreciate it.

2nd yup, I was successful in the end and got the program running following your directions! Yeah! However, a few extra steps were required as listed below.

1) Links for toplevel.py and remap.py had to be placed in the Python Path under usr/lib/python2.7/dist-packages so the program could find the files.
2) There were some commands used in the remap.py that required Machinekit to be downloaded from the git hub.
3) AXES=3 needed to be inserted under [TRAJ] in the .ini file

3rd would you be willing to post a couple of simple examples to use to trial the G71 code to get me going more quickly? I'm not sure I fully understand how to get the most out of this roughing cycle program. I can only seem to get it to follow the final profile right now so I know I'm doing something wrong.

Thank you again,

Barry

Barry wrote: 2) There were some commands used in the remap.py that required Machinekit to be downloaded from the git hub.

Are you running LinuxCNC or Machinekit? That's an either / or situation.

3rd would you be willing to post a couple of simple examples to use to trial the G71 code to get me going more quickly?

Look at the files that begin "G71" here: github.com/LinuxCNC/linuxcnc/tree/andypu...1type2remap/nc_files

OMG! Thank you! Your remap G71 program is amazing!!!!! It does everything that I need. The examples you directed me to helped greatly!

As for the need for Machinekit....I didn't realize that it was an either or deal where you were either running Linuxcnc or Machinekit. Based on your comment and experience I was obviously wrong about the need to download Machinekit. Thank you for educating me on that. I am definitely running LinuxCNC.

What made me think I needed to download Machinekit was that when I did a "locate" command in a terminal to find the stdglue, cycle_prolog, cycle_epilog, init_stdglue commands used in your program, I didn't think that those commands were found. It seemed that after I downloaded Machinekit those commands became available. Again I may have overlooked something here because I was at the beginning of a very steep learning curve and trying a lot of things to get everything working.

Thank you again.

Have a great week,

Barry