Need Help!- Problem with machine and program zero for tool movements

[merhas06]

Hello,

I’m new in CNC and I have a lathe machine ECOCA equipped with FANUC 0i-TC and rear turret.

After the machine setup (reference return position, tool offset, program zero…) and when I want to execute the program all tool movements are referenced to the zero machine and not to program zero[/B][/COLOR]. If for example I want to execute the bloc N10 G00 X100.0 Y100.0, the tools starts the movement to the right and the over travel alarm appear in the screen.

I find this problem at the beginning of the program and in the tool change position inside the program.

With many other programs this works very well and all tool movements are referenced to the program zero at the right end of the part.

I tried many alternatives to fix the problem, but this happens involuntarily and I can’t locate the problem and how to correct it.

Why this happens with some programs and not with others?

You are all kinds to help me.

[dcoupar]

Please post your program here.

[merhas06]

Hello dear,

These are the main blocs of the program. The simulation is perfect either on machine or on CIMCAD software. I tried G90 but it does not work.

O0000
N1 G21 G40 G99;
N2 T0100;
N3 G97 S1500 M04;
N4 G00 G42 X55.0 Z0 T0101 M08 (here, the tool moves to zero machine and not to the part??)
N5 G01 X-0.5 F0.2
N5 G01 Z1.0;
N6 X52.0;
N7 G71 U2.0 R0.5
N8G71 P11 Q20 U0.4 W0.2 F0.2
N10 G00 X14.0
N11 G01 X15.0 Z0 F0.2
N12 X20.0 Z-2.5
N13 Z-6.0
N14 G02 X20.0 Z-14 R5
N15 G01 Z-22.0
N16 G01 X20 Z-23.79
N17 G02 X30.17 Z-32.5 R10
N18 G01 X40.0 R5.0
N19 Z-70.0
N20 U2.0 W1.0
N21 G00 X100.0 Z100.0 T0100 M09 (here, the tool moves to zero machine and not to the part)
N22 M01
N23 T0200
N24 G97 S1500 M04
N25 T0202
N25 G00 G42 X55.0 Z1.0
N26 G70 P10 Q20
N27 G00 X100.0 Z100.0 T0200 M09 (here, the tool moves to zero machine and not to the part)
N28 M01
N29 ..
.GROOVE CUTTING
.
N35 ..
. (DRILLING operations)
.
M30
%

[dcoupar]

Originally Posted by merhas06 Hello dear, These are the main blocs of the program. The simulation is perfect either on machine or on CIMCAD software. I tried G90 but it does not work. O0000 N1 G21 G40 G99; N2 T0100; N3 G97 S1500 M04; N4 G00 G42 X55.0 Z0 T0101 M08 (here, the tool moves to zero machine and not to the part??) N5 G01 X-0.5 F0.2 N5 G01 Z1.0; N6 X52.0; N7 G71 U2.0 R0.5 N8G71 P11 Q20 U0.4 W0.2 F0.2 N10 G00 X14.0 N11 G01 X15.0 Z0 F0.2 N12 X20.0 Z-2.5 N13 Z-6.0 N14 G02 X20.0 Z-14 R5 N15 G01 Z-22.0 N16 G01 X20 Z-23.79 N17 G02 X30.17 Z-32.5 R10 N18 G01 X40.0 R5.0 N19 Z-70.0 N20 U2.0 W1.0 N21 G00 X100.0 Z100.0 T0100 M09 (here, the tool moves to zero machine and not to the part) N22 M01 N23 T0200 N24 G97 S1500 M04 N25 T0202 N25 G00 G42 X55.0 Z1.0 N26 G70 P10 Q20 N27 G00 X100.0 Z100.0 T0200 M09 (here, the tool moves to zero machine and not to the part) N28 M01 N29 .. .GROOVE CUTTING . N35 .. . (DRILLING operations) . M30 %

What values are in your geometry offsets for T01 and T02?

Please try it without the T0100 and T0200 in the retract move to index.

[hitachibos]

Hi
Everybody relax and slow down.

Try taking out the G42 in your first move line.
if that works then we can talk about tool nose radious compansation.

[merhas06]

Thank you very much for your precious ideas.

The Fanuc system is Fanuc 0i-TC. So it is a new one not an old.
The machine manual indicates that there is no need to write G54 because it is used by default.
I will take out the G42 and T0100 and T0200 and try again.

the big question is why with this program only? With other program it works correctly with G42 and T0100 T0200?????????????

Any way, I will try all these advices saturday. Tomorrow I have other duties outside. I will tell you the result later.

Thanks again dear friends.

[manolo23]

G90 doesnt work on lathe machine as Absolute programming it only works for milling machine

G90 for Lathe are for inside and outside canned cycle turning
ex.
G0 X50. Z1.
G90 X45. Z-20 F.25
X40.
X35.
X30.

usually i used this cycle in reboring of jaws.

i edit the program you just posted, try to run it..

PS. for safe run of program make a standard format method for all your programs safety of the operator and machine first..

dont cancel the compensation when your tool is still near your part.
start the compensation when you start cutting not on rapid positioning.
and dont include in one block the initial homing position and cancellation of tool offset (safety first)

i hope it helps..

Originally Posted by merhas06 Hello dear, These are the main blocs of the program. The simulation is perfect either on machine or on CIMCAD software. I tried G90 but it does not work. O0000 N1 G21 G40 G99; G28 U0. W0. N2 T0100; N3 G97 S1500 M04; T0101 M08 N4 G00 X55.0 Z0 G42 N5 G01 X-0.5 F0.2 N5 G01 Z1.0; N6 X52.0; N7 G71 U2.0 R0.5 N8G71 P11 Q20 U0.4 W0.2 F0.2 N10 G00 X14.0 N11 G01 X15.0 Z0 F0.2 N12 X20.0 Z-2.5 N13 Z-6.0 N14 G02 X20.0 Z-14 R5 N15 G01 Z-22.0 N16 G01 X20 Z-23.79 N17 G02 X30.17 Z-32.5 R10 N18 G01 X40.0 R5.0 ( what is this R5?) N19 Z-70.0 N20 U2.0 W1.0 N21 G00 X100.0 Z100.0 M09 T0100 ( no need to call T# again to cancel the offset just T0. will works) N22 M01 N23 T0200 N24 G97 S1500 M04 N25 T0202 N25 G00 (G42 )X55.0 Z1.0 G42 N26 G70 P10 Q20 N27 G00 X100.0 Z100.0 M09 T0200(T0) N28 M01 N29 .. .GROOVE CUTTING . N35 .. . (DRILLING operations) . M30 %

[merhas06]

Thanks manolo for re-editing the program.

You are perfectly right. For lathe, G90 is for outer diameter/ inner diameter cutting cycle.

Like C for chamfering, the R5.0 is the radius of the corner with the direction X to Z (I can use G03 for the same purpose).

The method that I use in all programs is recommended by Peter Smid in his famous CNC PROGRAMMING HANDBOOK Second Edition.

Your recommendations are well. I think I will review this method.

Thanks again