G76 giving an odd result

[dbohm]

I am having trouble programing my NovaTurn for the G76 canned cycle. I don't know what it should look like on this machine so maybe you could help. Here is an example thread.

%
O0000
N10 (FANUC - )
N90 G00 G40 G20 G99
N100 G28 U0.
N110 G28 W0.
N120 G00 G40 G20
N130 G28 U0
N140 G28 W0.
N150 M00
N160 (OD THREAD LEFT 55 DEG)
N170 T0101
N180 F0.05 S600
N190 M03
N200 G00 Z0.05 X2.04
N210 G76 P020100 Q0.01 R0.001
N220 G76 Z-0.5 X1.939 R0. P0307 Q0060 F0.05
N230 (END TOOL)
N240 M09
N250 G28 U0.
N260 G28 W0.
N270 M05
N280 M30
%

the behaviour the machine exhibits is that it starts the thread then just repeats the pass over and over again without end. It should do it about eight times.

Any ideas about how I am mis-programing this? I am at the latest releases of VR turning and the controller firmware.

Thanks in advance!

[Denford Admin]

This program looks to be working in the 3D simulation here:



I changed the top of the program to read:

Code: Select all

N10 (FANUC - ) 
N90 G00 G40 G20 G99 
[BILLET X2 Z3
N100 G28 U0. 

To let the 3D know it has a 2inch billet

The only thing you should be aware of is some of the G76 parameters MUST be in microns, whatever your programmed units are

TIP highlight G76 in the program editor and hit CTRL-F1 to get the help on this cycle

Other than that, I'd suggest you try the program in METRIC units - we occasionally have problems with IMPERIAL unit programs as we tend to do all testing with metric programs