Thread cutting at actual spindle speed

When cutting a thread, the spindle speed may tend to deviate under load. In order to execute thread tapping in such cases, the motion of the linear axes can be directly coupled to the spindle's actual speed. This means that a path motion is also synchronised to the zero passage of the actual positions.

To avoid set value jumps in path axes, a very noisy actual spindle speed can be smoothed by an averaging filter.

Release Note

Function available as of V3.01.3080.16.

The function is activated either with Thread cutting with actual spindle speed (P-CHAN-00834) or with the NC command #TURN [THREAD_CUT_ACT_SPEED=1 …].

Example

Thread cutting at actual spindle speed]

Define in channel parameters:

thread_cutting.use_actual_speed 1  ( P-CHAN-00834)

thread_cutting.n_cycles         5  ( P-CHAN-00835)

Alternative definition in NC program:

#TURN[THREAD_CUT_ACT_SPEED=1 THREAD_CUT_N_CYCLES=5]

Programing Example

Thread cutting at actual spindle speed

%spindle_test.nc

(Thread cutting at actual speed)

N15 M03 S40           ; Start spindle

N20 G00 X72 Z105      ; Approach

N25 G01 X68.16 F1000  ; Position at thread depth

N30 G33 Z48 K1.5      ; 1. Cut thread turn at command speed

N35 G00 X72           ; Retract

N40 Z105              ; and move

N45 G01 X68.16        ; to next start position

; Thread cutting at actual speed and filtered values

N50 #TURN[THREAD_CUT_ACT_SPEED=1 THREAD_CUT_N_CYCLES=20]

; 2. Cut thread turn at 180° at actual speed

N55 G33 Z10 K1.5 S.OFFSET=180

N60 G00 X72           ; Retract and move

N65 M05 X150 Z200     ; to end position

N70 M30