A helix is a cylindrical spiral that is programmed on a circular path with a constant pitch.
Application
Requirements
The path contours for a helix can only be programmed with a circular path CP.
Circular path CP around pole CC
You must define a pole CC before programming with polar coordinates.
Description of function

A helix is a combination of a circular path CP and a linear motion perpendicular to this path. You program the circular path CP in the working plane.
- Helices are used in the following cases:
- Large-diameter internal and external threads
- Lubrication grooves
Dependencies of different thread shapes
The table shows the dependencies between machining direction, direction of rotation and radius compensation for the different thread shapes:
Internal thread | Work direction | Direction of rotation | Radius compensation |
---|---|---|---|
Right-handed | Z+ | DR+ | RL |
Z– | DR– | RR | |
Left-handed | Z+ | DR– | RR |
Z– | DR+ | RL |
External thread | Work direction | Direction of rotation | Radius compensation |
---|---|---|---|
Right-handed | Z+ | DR+ | RR |
Z– | DR– | RL | |
Left-handed | Z+ | DR– | RL |
Z– | DR+ | RR |
Programming a helix

Define the same algebraic sign for the direction of rotation DR and the incremental total angle IPA. The tool may otherwise move on a wrong path.
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Example

- This example includes the following default values:
- M8 thread
- Left-handed thread miller
- The drawing and the default values allow deriving the following information:
- Internal machining
- Right-hand thread
- RR radius compensation
The derived information requires the machining direction Z–.
Dependencies of different thread shapes
- Specify and calculate the values below:
- Incremental total machining depth
- Number of thread grooves
- Incremental total angle
Formula | Definition |
---|---|
![]() | The incremental total machining depth IZ results from the thread depth D (depth) and from the optional thread run-in values RI (run-in) and thread run-out values RO (run-out). |
The number of thread grooves n (number) results from the incremental total machining depth IZ divided by the pitch P (pitch). | |
The incremental total angle IPA results from the number of thread grooves n (number) multiplied by 360° for one complete revolution. |
NC programs contained in this User's Manual are suggestions for solutions. The NC programs or individual NC blocks must be adapted before being used on a machine.
- Change the following contents as needed:
- Tools
- Cutting parameters
- Feed rates
- Clearance height or safe position
- Machine-specific positions, e.g. with M91
- Paths of program calls
Some NC programs depend on the machine kinematics. Adapt these NC programs to your machine kinematics before the first test run.
In addition, test the NC programs using the simulation before the actual program run.
With a program test you determine whether the NC program can be used with the available software options, the active machine kinematics and the current machine configuration.
11 L Z+1,25 R0 FMAX | ; Pre-position in the tool axis |
12 L X+4 Y+0 RR F500 | ; Pre-position in the plane |
13 CC X+0 Y+0 | ; Activate the pole |
14 CP IPA-3600 IZ-12.5 DR- | ; Cut the thread |
Alternative solution with repetition of program parts
NC programs contained in this User's Manual are suggestions for solutions. The NC programs or individual NC blocks must be adapted before being used on a machine.
- Change the following contents as needed:
- Tools
- Cutting parameters
- Feed rates
- Clearance height or safe position
- Machine-specific positions, e.g. with M91
- Paths of program calls
Some NC programs depend on the machine kinematics. Adapt these NC programs to your machine kinematics before the first test run.
In addition, test the NC programs using the simulation before the actual program run.
With a program test you determine whether the NC program can be used with the available software options, the active machine kinematics and the current machine configuration.
11 L Z+1.25 | ; Pre-position in the tool axis |
12 L X+4 Y+0 RR F500 | ; Pre-position in the plane |
13 CC X+0 Y+0 | ; Activate the pole |
14 LBL 1 | |
15 CP IPA-360 IZ-1.25 DR- | ; Cut the first thread groove |
16 LBL CALL 1 REP 9 | ; Cut the next nine thread grooves, REP 9 = number of remaining machining processes |
The solution approach uses the thread pitch directly as the incremental plunging depth per revolution.
REP shows the number of necessary repeats required for reaching the calculated ten infeed runs.