Indyx Fanuc CNC System: How an Automated Turning Center Runs

• 1
  What an Indyx Fanuc CNC system actually controls
• 2
  How the dual-spindle transfer works in the cycle
• 3
  Tool changing and driven tools in the turret
• 4
  Materials, tolerances, and the real limits
• 5
  When the automated cycle pays off in production
• 6
  Where an automated turning center fits, and where it does not

An Indyx Fanuc CNC system is a turning center built around a Fanuc control, usually in the 31i family, with one or two motorized spindle heads and a tool turret that can hold driven tools. The control drives the axes, the spindle orientation, the tool change, and the part transfer between spindles. Nothing about that is exotic. The value sits in how tightly those motions are sequenced.

The machine is arranged so a part can be cut on the main spindle, picked up by the counter spindle, and finished on the back face without a human touching it. That is the whole point of the design. Once the bar feeder loads a bar, the cycle can run unattended through turning, drilling, milling, and parting off.

Fanuc control matters here because the ladder logic and the servo tuning are stable across machine generations. A programmer who knows G-code on one Fanuc lathe can move to another without relearning the cycle structure. Setup becomes about the part, not the controller.

We run these turning centers alongside our milling fleet. For round parts with a back-side feature, the automated transfer often removes a second operation entirely.

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  Main spindle plus counter spindleFront and back faces cut in one cycle.
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  Driven tools in the turretCross holes and flats cut without a mill.
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  Fanuc 31i class controlConsistent G-code and macro behavior.
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  Bar feeder interfaceUnattended runs from bar stock.

The cycle starts on the main spindle. The part is turned to the front-side dimensions, then the counter spindle moves in, grips the part, and the parting tool cuts it free. The counter spindle then indexes to the back-working station and finishes the second face. The sequence is written into the program, so the transfer happens at a fixed point in the cycle every time.

This matters for concentricity. When a part is cut and then re-chucked in a separate operation, the second setup adds its own runout. On a dual-spindle transfer, the counter spindle picks up the part while it is still on the same centerline, so the back-face features stay aligned with the front. For a shaft with a bore on each end, that is often the difference between one setup and two.

The trade-off is program complexity. The transfer point has to be safe, the grip pressure has to match the material, and the parting tool has to leave a clean face. On thin-wall parts, the counter spindle grip can distort the bore if the pressure is set too high. We adjust the grip and often add a soft jaw or a collet insert.

Cycle time is the second consideration. The transfer adds a few seconds, but it removes a whole second operation, a re-chuck, and a second inspection. On a run of any size, the transfer usually wins.

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  Transfer on the same centerlineKeeps front and back features concentric.
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  Grip pressure per materialLower for thin-wall and soft alloys.
• 3
  Parting tool conditionA worn tool leaves a burr on the cut face.

The turret indexes to bring each tool into position. On a live-tool turret, some stations carry driven holders so a cross drill or a small end mill can cut after the turning pass. That lets the machine put a hex, a flat, or a cross hole into the same cycle as the turning. The alternative is a mill, a second fixture, and a second setup.

The limit is access, not power. A driven tool in a turret reaches the part from one direction, and its travel is short. A deep pocket or a feature on the far side of the part is usually out of reach. When a drawing has more than a few milled features, a mill-turn center or a 5-axis machine is the better home for it.

Tool change time is short on these machines, but it is not zero. On a high-mix job, the number of tools in the program drives the setup cost more than the cycle time does. We group tools so a family of parts can share a turret load and skip a full setup between runs.

For a part that is mostly turned with one or two milled flats, the live-tool turret is efficient. For a part that is mostly milled with one turned bore, it is the wrong machine.

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  Live tooling suits cross holes and flatsShort reach, one direction.
• 2
  Deep or far-side featuresRoute to mill-turn or 5-axis.
• 3
  Tool groupingCuts setup time on part families.

Tolerance on a well-set turning center lands around ±0.005 mm on a stable diameter. That is not a promise for every feature. A long, slender shaft deflects under cutting force, and a thin-wall ring moves when it is released from the chuck. On those parts, we add support, take lighter passes, or accept a wider band on the free end.

Surface finish depends on the tool and the material. A turned finish typically sits at Ra 0.8–1.6 μm, and a fine pass with a fresh insert can reach Ra 0.2–0.8 μm on aluminum and free-machining steel. Harder alloys and interrupted cuts push the finish coarser. If a drawing calls for a mirror bore, that is usually a honing or a fine-boring step, not a turning pass.

Material choice drives the cycle. Aluminium 6061 and 2024 cut fast and hold tolerance well. Stainless 303 and 316L work but need slower speeds and more coolant. Titanium TC4 and Inconel cut hot and wear tools quickly, so the cycle time and tool cost rise. Brass and copper cut cleanly but can be gummy at low speeds.

The machine does not care about part volume. It cares about stability. A rigid setup on a short part holds tolerance all day. A long overhang on a soft material will drift, no matter how good the control is.

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  ±0.005 mmStable diameter, rigid setup.
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  Ra 0.8–1.6 μmTypical turned finish.
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  Ra 0.2–0.8 μmFine pass on aluminum and free-machining steel.
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  Thin-wall and long shaftsExpect a wider band; plan support.

The automated cycle pays off when a part has a back-side feature and a run long enough to matter. A hundred shafts with a bore on each end is a clear case. The machine cuts the front, transfers, cuts the back, and parts off. One operator can watch several machines.

It pays off less when the run is one or two pieces. The programming and setup for the transfer take time, and that time does not shrink with quantity. For a single prototype, a simple lathe with a second op is often faster to first article.

There is no minimum order quantity here. We run from one prototype to 10,000+ part runs. The choice between an automated transfer and a manual second op is a judgment about the part and the quantity, not a policy.

For a family of similar parts, the turret load and the program structure can be reused. That is where the setup cost per part drops fastest. We keep the tool list and the transfer macro consistent across a family so a new variant is a small edit, not a new program.

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  High-mix familiesReuse turret load and transfer macro.
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  One-off prototypesSecond op may reach first article sooner.
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  No minimum order quantityOne prototype to 10,000+ parts.