Operation Manual

HEIDENHAIN CNC PILOT 640 283
4.6 Thread and undercut cycles
Recut (longitudinal) thread
Call the thread-cutting menu
Select thread cycle
Press the Recut soft key
 On: Inside thread
 Off: Outside thread
This optional cycle reworks a single-start thread. Since you have
already unclamped the workpiece, the CNC PILOT needs to know the
exact position of the thread. Place the cutting tip of the tap drill in the
center of a groove and transfer the positions to the parameters
measured angle and measured position by pressing the Take over
position soft key. From these values the cycle then calculates the
angle of the spindle at the starting point.
This function is available only in manual operation.
Cycle parameters
X1 Starting point of thread
Z2 End point of thread
F1 Thread pitch (= feed rate)
U Thread depth – No input:
 Outside thread: U=0.6134*F1
 Inside thread: U=–0.5413*F1
I Maximum infeed
 I<U: First cut with cutting depth I — further cuts:
reduction of cutting depth
 I=U: One cut
 No input: Calculation from U and F1
C Measured angle
ZC Measured position
A Infeed angle (range: -60° <= A < 60°; default: 30°)
 A<0: Infeed on left thread flank
 A>0: Infeed on left right flank
R Remaining cutting depth—only with GV=4 (default:
1/100 mm)
MT M after T: M function that is executed after the tool call T.
MFS M at beginning: M function that is executed at the
beginning of the machining step.