HEIDENHAIN iTNC 530 (340 49x-01) ISO programming User Manual
Page 303

HEIDENHAIN iTNC 530
303
8.4 Cy
cles f
o
r Milling P
o
c
k
ets, St
uds and Slots
Finishing
5
Inasmuch as finishing allowances are defined, the TNC then 
finishes the pocket walls, in multiple infeeds if so specified. The 
pocket wall is approached tangentially.
6
Then the TNC finishes the floor of the pocket from the inside out. 
The pocket floor is approached tangentially.
Before programming, note the following:
Pre-position the tool in the machining plane to the starting 
position (circle center) with radius compensation R0.
The TNC runs the cycle in the axes (machining plane) with 
which you approached the starting position. For example, 
in X and Y if you programmed G79:G01 X... Y... or in U 
and V if you programmed G79:G01 U... V...
The TNC automatically pre-positions the tool in the tool 
axis. Note Parameter Q204 (2nd set-up clearance).
The algebraic sign for the cycle parameter DEPTH 
determines the working direction. If you program 
DEPTH = 0, the cycle will not be executed.
At the end of the cycle, the TNC returns the tool to the 
starting position.
At the end of a roughing operation, the TNC positions the 
tool back to the pocket center at rapid traverse. The tool is 
above the current pecking depth by the setup clearance. 
Enter the setup clearance so that the tool cannot jam 
because of chips.
Enter in MP7441 bit 2 whether the TNC should output an 
error message (bit 2=1) or not (bit 2=0) if a positive depth 
is entered.
Danger of collision!
Keep in mind that the TNC reverses the calculation for pre-
positioning when a positive depth is entered. This 
means that the tool moves at rapid traverse in the tool axis 
at safety clearance below the workpiece surface!
