Indexed rotary-axis retrofit solution

External 4th & 5th Axis Retrofit for 3-Axis CNC Machines

Add indexed rotary machining to supported FANUC, Mitsubishi, Brother and Siemens CNC machines. Compatible FANUC and Mitsubishi configurations can retain the machine's original handwheel; Brother and Siemens configurations require an additional electronic handwheel. A complete project is often lower in cost than a native OEM axis expansion, depending on the CNC configuration and project scope.

Real CNC machine using a rotary-axis setup during machining
Real machining footage from a rotary-axis application. Final configuration depends on machine space, CNC control and the required process.
01 / COMPATIBILITY

FANUC, Mitsubishi, Brother and Siemens

Common control families can be supported after the exact CNC model, available interface and machine configuration are confirmed.

02 / OPERATION

Handwheel operation by CNC system

Compatible FANUC and Mitsubishi configurations can retain the machine's original handwheel. Brother and Siemens configurations require an additional electronic handwheel for setup and manual positioning.

03 / INVESTMENT

Often lower in cost than a native OEM axis expansion

A matched external-axis package can reduce total investment substantially compared with an OEM additional-axis package.

Application boundary

When this retrofit is the right approach

External control is primarily intended for indexed positioning, multi-face machining and repeatable angular moves. The required motion determines whether external or native CNC integration is appropriate.

A strong fit for indexed machining

  • The existing 3-axis machine is mechanically reliable.
  • Workpieces require side drilling, radial features or multi-face milling.
  • Fixed-angle indexing is sufficient for the machining process.
  • An OEM additional-axis package is too expensive or unavailable.
  • The machine has sufficient table load, travel, spindle clearance and cabinet space.

Needs a native-axis architecture review

  • Continuous simultaneous X/Y/Z/A or full 5-axis interpolation is required.
  • The process depends on high-speed contouring across multiple axes.
  • OEM-specific safety, collision avoidance or advanced kinematics are mandatory.
  • The machine has no suitable signal, communication or cabinet interface.
  • The rotary unit and workpiece exceed the available load or working envelope.

Investment and capability

OEM axis expansion vs external indexed-axis retrofit

The lower-cost route is valuable only when it matches the required motion. This comparison helps define the correct starting point.

Decision point
OEM axis expansion
Yidai external retrofit
Typical investment
Higher machine-brand hardware, software and service cost.
Often lower in cost than a native OEM axis expansion, depending on configuration and scope.
Motion capability
Best route when full simultaneous interpolation and native kinematics are required.
Designed primarily for indexed positioning, fixed-angle moves and multi-face machining.
Integration
Depends on the original CNC builder's servo architecture and service support.
Matched rotary table, controller, servo drive and communication method are selected for the machine.
Handwheel operation
Normally integrated through the native CNC additional-axis function.
Compatible FANUC and Mitsubishi configurations can retain the original handwheel; Brother and Siemens configurations require an additional electronic handwheel.
Best use
Advanced simultaneous contouring and machine-builder-specific functionality.
Cost-conscious upgrades for indexed drilling, milling, positioning and repeatable multi-side work.

Communication options

How the CNC and rotary controller work together

The exact method is selected from the CNC control model, available interfaces, program workflow and operator requirements.

TCP/IP integration

Network integration and handwheel operation

On compatible FANUC and Mitsubishi configurations, network communication can coordinate command and status data and allow the machine's built-in handwheel to jog the rotary axis. Brother and Siemens configurations require an additional electronic handwheel. Compatibility must be checked by exact control model and machine-builder implementation.

RS232 communication

Serial command or position transfer

RS232 can be practical on controls with suitable serial functions. The operating sequence and available feedback depend on the CNC, and a separate controller interface may still be used.

I/O and M-code trigger

Simple, robust indexed positioning

The CNC sends start or position-selection signals and receives completion or alarm status. Rotary positions are managed by the external controller; this method is not continuous interpolation.

System architecture

A matched retrofit package from command to motion

Selection covers the mechanical rotary unit and the complete control path, not just a single product.

CNC control
TCP/IP, RS232 or I/O
External axis controller
Servo drive and motor
4th or 5th axis rotary table
Yidai servo drives and motors for external 4th and 5th axis CNC control systems Yidai servo drive range for CNC rotary table retrofit systems

Complete control package

Servo drive + servo motor + axis-card controller

The first-generation YD-1 uses a standalone external architecture. Yidai's core control package includes the matched servo drive, servo motor and axis-card controller. The rotary table, brake circuit, cables and machine interface are confirmed separately for the table size, load, control method and target machine.

Indexed machining workflow

How a typical cycle operates

The host CNC remains responsible for the original X, Y and Z machining cycle while the external system manages rotary positioning.

01

Machining stops safely

The program reaches the rotary-positioning point and confirms the spindle or cutting motion is safe.

02

CNC sends a command

The control uses TCP/IP, RS232 or an I/O/M-code signal according to the selected integration.

03

Rotary axis indexes

The external controller commands the servo and positions the rotary table at the required angle.

04

Position is confirmed

The external system completes positioning, applies the brake if required and returns ready status.

05

Machining continues

The host CNC resumes the X/Y/Z program for the next indexed face or feature.

Real installation evidence

Machine-side and cabinet-side implementation

The rotary unit works inside the machining enclosure. The external controller and servo hardware are installed separately in the electrical cabinet.

Real machine setup Field footage showing the rotary-axis application inside the CNC machining area.
Real CNC electrical cabinet wiring for an external rotary axis retrofit
Real electrical-cabinet integration Actual servo and control wiring. Final layout varies with cabinet space, CNC interface and safety requirements.

Before selection

Send the information that determines compatibility

A model number alone is not enough. These details allow the rotary table, controller method, servo size and installation approach to be evaluated together.

Machine and CNC model Machine builder, exact machine model and complete CNC control model.
Working envelope Machine table size, X/Y/Z travel, spindle clearance and allowable table load.
Workpiece details Dimensions, weight, center of gravity, clamping method and required orientations.
Machining process Indexed positions, features to be machined, cycle sequence and accuracy requirements.
Interface and cabinet Available TCP/IP, RS232 or I/O signals plus clear photos of the electrical cabinet.
Operator requirement Confirm the CNC system and whether the original or an additional electronic handwheel will be used.

Frequently asked questions

External CNC axis retrofit FAQ

Does the solution support FANUC, Mitsubishi, Brother and Siemens CNC controls?

These four control families can be evaluated, but compatibility is not determined by the brand name alone. We need the exact CNC model, software version, available TCP/IP, RS232 or I/O interface, machine configuration and required operating sequence before confirming a solution.

How does handwheel operation differ by CNC system?

Compatible FANUC and Mitsubishi configurations can retain the CNC's built-in handwheel. Brother and Siemens configurations require an additional electronic handwheel. The exact CNC model, software version, communication method and machine-builder implementation must be confirmed for each machine.

Is this a simultaneous 4-axis or 5-axis system?

The external solution is primarily designed for indexed positioning and multi-face machining. Projects requiring full simultaneous interpolation, advanced kinematics or high-speed multi-axis contouring need a separate review of the CNC and native servo architecture.

How much does an external retrofit cost compared with an OEM upgrade?

A complete external-axis project is often lower in cost than a native OEM additional-axis upgrade. The actual difference depends on rotary-table size, servo power, control method, brake system, wiring, installation scope and the target machine.

What information is required for a recommendation?

Send the machine make and model, exact CNC control model, table and travel dimensions, workpiece size and weight, machining process, required indexing angles, cabinet photos and available communication interfaces.

Start with your CNC model and workpiece

We will review the machine envelope, CNC interface, handwheel requirement, rotary-table size and control method before recommending a package.

Request a Compatibility Review