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canned cycle for lathe with fanuc control 
Depending on your control the normal calls are:
G70 (Finishing Cycle)
G71 (OD or ID turning cycle)
G72 (Facing Cycle)
Depending on your control the cycles are sometimes different in their build up.
Fanuc 6T Cycle Line requires a one line cycle as follows:
G71 P1 Q7 D4000 R2.0 U0.5 W0.2 F0.1
G71 - Is the cycle type
P1 - is the first profile line sequence number
Q7 - is the last prifile line sequence number
D4000 - is the depth of cut in microns
R2.0 - is the clearance of the X axis when rapid traversing back for the next cut in mm
U0.5 - is the amount of material to be left on the OD (X) incremental
W0.2 - is the material to be left on the shoulders (Z) incremental
F0.1 - is the feed rate (either in mm/rev or mm/min depending on your feed type)
On later controls a two line cycle is required as follows:
G71 U4.0 R2.0
G71 P1 Q7 F0.1 U0.5 W0.2
LINE 1
G71 - Is the cycle type
U4.0 - is the depth of cut in mm
R2.0 - is the clearance of the X axis when rapid traversing back for the next cut in mm
F0.1 - is the feed rate (either in mm/rev or mm/min depending on your feed type)
LINE 2
G71 - Is the cycle type
P1 - is the first profile line sequence number
Q7 - is the last prifile line sequence number
U0.5 - is the amount of material to be left on the OD (X) incremental
W0.2 - is the material to be left on the shoulders (Z) incremental
Excuse me for being a metric type person.
You must first move to your start position eg: Z clearance from the face of you billet and X to the outside diameter of your billet.
I might be a bit rusty here as it was a while ago but it is something like this->>
ONE LINE CYCLE (Fanuc 6T)
Billet diameter is 80mm
G0 X80.0 Z2.0 (Start Position before commanding the cycle)
G71 P1 Q7 D4000 R2.0 U0.5 W0.2 F0.1
N1 G0 X32.0
N2 G1 Z0.0
N3 G1 X40.0 Z-4.0
N4 G1 Z-30.0
N5 G1 X60.0 Z-60.0
N6 G1 Z-75.0
N7 G1 X80.0
G70 P1 Q7 F0.02 (This line is optional - If you command this line after the roughing cycle it will read sequence number N1 - N7 and do one complete finish profile cut)
TWO LINE CYCLE
Billet diameter is 80mm
G0 X80.0 Z2.0 (Start Position before commanding the cycle)
G71 U4.0 R2.0
G71 P1 Q7 F0.1 U0.5 W0.2
N1 G0 X32.0
N2 G1 Z0.0
N3 G1 X40.0 Z-4.0
N4 G1 Z-30.0
N5 G1 X60.0 Z-60.0
N6 G1 Z-75.0
N7 G1 X80.0
G70 P1 Q7 F0.02 (This line is optional - If you command this line after the roughing cycle it will read sequence number N1 - N7 and do one complete finish profile cut)
The build up of an ID profile is the same but you start at your drill hole diameter prior to executing the cycle and your R, U and W figures are negitive figures.
I hope this helps
Originally Posted by CNC PGMR 
