HEIDENHAIN TNC 360 ISO Programming - Manual (Page 118)

5-35 TNC 360
5 Programming Tool Movements
5.5 Path Contours - Polar Coordinates
Example for exercise: Tapping
Given data
Thread:
Right-hand internal thread
M64 x 1.5
Pitch P: 1.5 mm
Start angle A
S
: 0°
End angle A
E
: 360° = 0° at Z
E
= 0
Thread revolutions n
T
: 8
Thread overrun
• at start of thread n
S
: 0.5
• at end of thread n
E
: 0.5
Number of cuts: 1
A =0
°
E
A =0
°
S
A = 0
°
G13
A = –180
°
Calculating the input values
• Total height h: H = P . n
P = 1.5 mm
n = n
T
+ n
A
+ n
E
= 9
h = 13.5 mm
• Incremental polar coordinate angle H: H = n . 360°
n = 9 (see total height H)
IPA = 360°
. 9 = 3240°
• Start angle A
S
with thread overrun n
S:
n
S
= 0.5
The start angle of the helix is advanced by 180° (n = 1 corresponds
to 360°). With positive rotation this means that
A
S
with n
S
= A
S
– 180° = –180°
• Starting coordinate: Z = P . (n
T
+ n
S
)
= –1.5 . 8.5 mm
= –12.75 mm
The thread is being cut in an upward direction towards Z
E
= 0;
therefore Z
S
is negative.
Part program
%S536I G71 * ........................................... Begin program
N10 G30 G17 X+0 Y+0 Z–20 * ................. Define the workpiece blank
N20 G31 G90 X+100 Y+100 Z+0 *
N30 G99 T11 L+0 R+5 * ........................... Define the tool
N40 T11 G17 S2500 * ............................... Call the tool
N50 G00 G40 G90 Z+100 M06 * .............. Retract the spindle and insert the tool
N60 X+50 Y+30 * ..................................... Pre-position in the bore center in X, Y
N70 G29 * ................................................. Capture position as a pole
N80 Z–12 M03 * ....................................... Move the tool to starting depth
N90 G11 G41 R+32 H–180 F100 * ........... Move with radius compensation and reduced feed to the first contour
.................................................................. point
N100 G13 G91 H+3240 Z+13.5 F200 * Helical interpolation; incremental angle and tool movement in the Z axis
N110 G00 G40 G90 X+50 Y+30 * ............ Retract in X, Y(absolute values), cancel radius compensation
N120 Z+100 M02 * ................................... Retract in Z
N9999 %S536I G71 *