[Dam]

Hello,
I'm a mechanical engineer, and I'm developing a set of macros to ease the work of similar parts on our lathes.

What I need now is to use the G71 built in macro inside a custom macro.
The use of G71 is clear to me: in the second line of the G71 calling I have to put e.g. P100 Q200 (together with some other parameters) to tell the control that my profile is defined between lines N100 and N200.

But how can I put the G71 command inside a CUSTOM MACRO having the profile defined in the MAIN PROGRAM?

In other words, how can I realize something similar to what Fanuc programmed, when it created a macro (G71) that uses a block (of profile definition) in the main program?

I need this for a lot of reasons that I can't explain now.

Any idea?

[Dam]

PS: I work on fanuc 0i, 18 and 21

[stevo1]

What you can do is define the shape using variables in your main program and then use the subprogram to machine the part with G71.

O0001(main program)
#100=10.(od diameter)
#101=1.(z distance to cut)
#102=.01(finish stock on x)
#103=.05(pick size)
#104=.01(feed)
#105=200(speed)
M98P2
M30

O0002(sub program)
…
G0X11.Z1.
Z.1
G96S#200M3
G71P100Q200U#102W0D#103F#104
N100G0X#100
Z-#101
N200X#101+.1
G0Z1.
M99

I just slapped this together as a reference so I am sure that there are some errors in it but it gives you the general idea.

Just as a side note I don’t like canned cycles. They usually have a lot of wasted time in them. If you are going to go this far I would just write a macro designed to do what you need instead of putting a canned cycle in it. But there is nothing wrong with doing it as above.

Stevo