Siemens sinumerik 840D sl Operating Manual page 372

Programming technology functions (cycles)
8.4 Milling
Parameter Description
Machining Face C

surface
Face Y

(only for
Peripheral surface C

ShopTurn)
Peripheral surface Y

∇ (roughing)
Machining 
∇∇∇ (finishing)

Machining direction:
Z0 → Z1

Machining from top to bottom
Z1 → Z0

Machining from bottom to top
Direction of rotation of the thread:
Righthand thread

A righthand thread is cut.
Lefthand thread

A lefthand thread is cut.
Position of the thread:
Internal thread

An internal thread is cut.
External thread

An external thread is cut.
NT Number of teeth per cutting edge
Single or multiple toothed milling inserts can be used. The motions required are
executed by the cycle internally, so that the tip of the bottom tooth on the milling tool
cutting edge corresponds to the programmed end position when the thread end
position is reached. Depending on the cutting edge geometry of the milling insert, the
retraction path must be taken into account at the base of the workpiece.
Machining position:
(only for G code)
Single position

Position pattern (MCALL)

The positions refer to the center point:
X0 Reference point X – (only for single position)
Y0 Reference point Y – (only for single position)
Z0 Reference point Z
(only for G code)
Z1 or X1 End point of the thread (abs) or thread length (inc)
(Z1 for machining surface, face C/Y or X1 for peripheral surface C/Y)
Table Thread table selection:
without

ISO metric

Whitworth BSW

Whitworth BSP

UNC

372
Operating Manual, 07/2010, 6FC5398-8CP40-0BA0
Unit
mm
mm
mm
mm
Turning