Rotary table types
| Type | Control | Post output |
|---|---|---|
| NC rotary table (4th axis) | Full CNC axis | A.. or B.. coordinates, clamp codes |
| Indexer (M-code driven) | Separate controller, signalled by M-code | Index command, no continuous motion |
| Tilting rotary table (4th + 5th) | Two CNC axes | 3+2 or simultaneous 5-axis output |
Data the post needs
- Axis name and which linear axis it rotates around.
- Positive rotation direction (seen from the machine's point of view).
- Resolution (e.g. 0.001°) and minimum index for indexers.
- Clamp and unclamp M-codes.
- Rotary centre position (for tilting tables and non-TCP output).
- Maximum rotary feed and speed.
Indexer example
(Indexer controlled by M-code and a separate controller)
(Index table to next preset position)
M* (index signal - builder specific)
G04 X1. (wait for index complete, if no feedback signal)
(... machining ...)Indexers vary widely; some wait for a completion signal, others rely on programmed dwell. The post follows the installation's wiring and documentation.
Tilting rotary tables
A tilting rotary table turns a VMC into a 5-axis machine. The post then needs 5-axis logic: kinematics, TCP or rotated coordinates, and limit handling, just like a trunnion machine.
A rotary table is only as useful as the post that drives it.
Rotary table post development
See our CNC post processor development service and 4-axis milling posts.