
B-63782EN/01 NC FUNCTIONS 4.THREAD CUTTING
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4.1 THREAD CUTTING (G33)
The G33 command produces a straight or tapered thread having a
constant lead.
Fig.4.1 (a) Thread
Format
Explanation
In general, thread cutting is repeated along the same tool path in rough
cutting through finish cutting for a screw. Since thread cutting starts
when the position coder mounted on the spindle outputs a 1-turn signal,
threading is started at a fixed point and the tool path on the workpiece is
unchanged for repeated thread cutting. Note that the spindle speed
must remain constant from rough cutting through finish cutting. If not,
incorrect thread lead will occur.
G33 IP_ F_ Q_ ;
F_ : Larger component of lead
Q_ : Angle by which the threading start angle is shifted
(0 to 360deg.)
L
Straight thread
L
L
Taper thread
Front thread
troke thread
L : Lead