Dual-spindle layouts
| Layout | Description |
|---|---|
| Opposed spindles | Main and sub-spindle face each other; part is transferred |
| Parallel twin spindles | Two spindles side by side, often with a loader between them |
What the post must manage
- Spindle selection codes and separate speed commands per spindle.
- Mirrored Z direction when cutting on the sub-spindle.
- Work offsets for each spindle.
- C-axis on each spindle for live tooling.
- Transfer sequence: synchronise, approach, clamp, cut off, retract.
Transfer sequence
1. Main spindle stops or spindles synchronise at speed
2. Sub-spindle moves to pickup position
3. Sub-chuck clamps (confirmation check)
4. Cut-off tool parts off
5. Sub-spindle retracts with part
6. Back-working operations run on sub-spindle
7. Part ejected / caughtEvery step uses machine-specific codes (sync, chuck, torque skip or pickup confirm, ejector). These come from the builder's manual and are tested carefully on the machine.
Mirrored coordinates
On the sub-spindle, positive Z usually points the opposite way. The post either uses the controller's mirror function or outputs transformed coordinates, depending on the machine and CAM setup.
Safety first
Transfers involve two spindles, a chuck and a cutting tool meeting at one point. The first run should be done step by step with reduced rapids and single block.
Dual-spindle posts turn two operations into one unattended cycle.
Dual-spindle post development
See our CNC post processor development service and mill-turn posts.