
6. Interpolation Functions
6.7 Thread Cutting
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6.7 Thread Cutting
6.7.1 Constant Lead Thread Cutting; G33
Function and purpose
The G33 command exercises feed control over the tool which is synchronized with the spindle
rotation and so this makes it possible to conduct constant-lead straight thread-cutting and tapered
thread-cutting. Multiple thread screws, etc., can also be machined by designating the thread cutting
angle.
Command format
G33 Z__(X__ Y__
α
__) F__ Q__ ;
(Normal lead thread cutting commands)
Z (X Y
α
)
: Thread end point
F
: Lead of long axis (axis which moves most) direction
Q
: Thread cutting start shift angle, (0.000 to 360.000°)
G33 Z__(X__ Y__
α
__) E__ Q__ ;
(Precision lead thread cutting commands)
Z (X Y
α
)
: Thread end point
E
: Lead of long axis (axis which moves most) direction
Q
: Thread cutting start shift angle, (0.000 to 360.000
°
)
Detailed description
(1) The E command is also used for the number of ridges in inch thread cutting, and whether the
ridge number or precision lead is to be designated can be selected by parameter setting.
(Precision lead is designated by setting the parameter "#1229 set 01/bit 1" to 1.)
(2) The lead in the long axis direction is commanded for the taper thread lead.
Tapered thread section
When a<45
°
, the lead is LZ.
When a>45
°
, the lead is LX.
When a=45
°
, the lead can be in either LX or LZ.
LZ
Z
X
LX
a