Rockwell Automation 8520-ARM2 9/Series CNC AMP Reference Manual Documentation Set - Manual (Page 409)

Letter Format Parameters
Chapter 17
17-11
The Lead word letter format parameter is covered in Lead: Word Format
on page 17-11.
Function
This parameter is used for lathe controls and cylindrical grinder
applications only. It refers to the F-word that is used to program the thread
lead in one of these threading methods:
G-Code System
Lathe Grinder
A B C Surface Cylindrical Description
G32 G32 G33 G33 G33 Constant lead thread-cutting mode
G33 G33 G34 G34 G34 Variable lead thread-cutting mode
G92 G78 G21 — — Single Pass Threading Cycle
G76 G76 G78 — — Multi-Pass Threading Cycle
This F-word represents the thread lead (in inches or millimeters of axis
travel per spindle revolution) along the axis with the largest programmed
distance to travel to make the thread cut.
This parameter specifies the maximum number of digits that are permitted
to the left and to the right of the decimal point in the F-word format when
in inch or metric modes.
Parameter Parameter Number
Lead: Word Format [477]
Range
Selection Result
(a) 2.5 ipr 3.4 mmpr
(b) 1.5 ipr 2.4 mmpr
(c) 3.4 ipr 4.3 mmpr
(d) 2.4 ipr 3.3 mmpr
(e) 1.4 ipr 2.3 mmpr
(f) 4.3 ipr 5.2 mmpr
(g) 3.3 ipr 4.2 mmpr
(h) 2.3 ipr 3.2 mmpr
(i) 1.3 ipr 2.2 mmpr
Notes
This parameter is a global parameter; it applies to all axes and processes.
17.13
Lead: Word Format
17.14
Lead: Word Format