G72 canned cycle woes.

[Cncsteve]

Hello all,

I’m new to cnc and trying to run a simple facing off program on my lathe by using the g72 cycle, I go to part set z0 and x0 go back to main screen load program press cycle start and the machine rapids to clearance positions but does not move back to z0 to start the job it stays in clearance positions and starts the job from there completely missing the job, attached is the code I’m using for this operation and the graph, is their something I’m doing wrong?

Regards
Steve.

[cnckeith]

Use Intercon for your first time so it creates good g code.




related.

[cnckeith]

post a fresh report.zip and photos , the machine and configuration has to be right before attempting to cut any parts.
here is how.

viewtopic.php?f=60&t=1043

[cncsnw]

So, if the job is running, and you slow it down and press Feed Hold when it gets to the end of line 3 ("G0 X47.0 Z2.0"):
1) Where is the tool tip, relative to the part?
2) What positions does the DRO show?
3) What Tool number does the status window show?

Instead of taking close-up pictures of small parts of the CNC12 screen, take pictures that show the whole screen. It matters what WCS is selected (shown in the upper left corner). It matters what tool offsets are active (shown in the status window at the upper right). It matters what error messages are shown in the message box.

Also, along with your Report, post a copy of the CNC program file. If someone wants to try to reproduce your problem, you don't want to make them waste their time typing in the fragment of your program that was pictured on the screen.

My guess is that your problem is the lack of a tool/offset callout in the CNC program.

It could also be that your G72 command references a profile that begins on line N11 and ends on line N22, but maybe your program file does not have those lines. Impossible to tell without seeing a complete copy of the program file.

[Cncsteve]

Thank you so much for your replies, seems I’m rushing into things trying to get a machine to cut jobs when it’s not right.
At the end of line 3 the machine is 0.800 of the job consistently where it should start from 0.0 the machine does the same in conversational programming too so something is clearly wrong somewhere, I’ll sent the report when I get in from work tonight.

Steve.

[cncsnw]

What does "the machine is 0.800 of the job" mean?

[Cncsteve]

0.8mm away from the face of the part.
And the machine works as it should when I write my own g code without using g72 for some reason.

[suntravel]

Post the suspect g-code.

Uwe

[Cncsteve]

G96 S280 M03;
GO X47.0 Z2.0;
G72 WO.3 R1.0;
G72 P11 Q22 UO W0.5 F200;
N11 GO Z0.0;
G1 X-1.0 F200;
N22 Z2.0;
M05;

[cnckeith]

please post a fresh report.zip otherwise we are just guessing.