Currently, we are modernizing a Gildemeister NEF 320, originally equipped with a Heidenhain CNC Pilot 3110 control. The machine is mechanically impressive due to its very good condition – an ideal candidate for a cost-effective retrofit instead of an expensive new purchase.

Initial Situation and Challenges

A particular challenge with this machine is the original drive technology:

  • Communication to the Siemens servo drives via fiber optic cables

  • Proprietary system architecture

  • No easy integration of modern control systems

Continued operation of the existing drives was therefore not possible – a complete replacement of the power amplifier stages was necessary.

New Control and Drive Architecture

The new solution is based on an open and future-proof platform:

Control & Communication

  • LinuxCNC as the central CNC control

  • MESA FPGA Hardware for real-time signal processing

  • 7i92M Ethernet Interface – complete communication via Ethernet

Drives

  • New Lichuan EtherCAT servo drives

  • Main spindle via DELTA frequency inverter

Encoder Integration

  • Particularly critical: Evaluation of the main spindle encoder

  • Implementation via MESA FPGA cards for precise synchronization (thread cutting, constant cutting speed, etc.)

Modern operating concept

The original monitor was replaced by an industrial touchscreen.

The user interface used is ProbeBasic:

  • Completely touch-optimized

  • Operating concept based on modern industrial controls

  • Direct generation of standard cycles via the interface

  • Integration of numerous LinuxCNC cycles (turning, threading, drilling, etc.)

The result is an intuitive and powerful HMI without proprietary restrictions.

Control cabinet and handheld operating device

The control cabinet is largely preserved:

  • Existing contactor control remains in its original state

  • Replacement of:

    • Power stages

    • I/O cards

The greatest challenge lay in the manual control device:

  • Special Heidenhain interface

  • Communication via Eltromatic bus

  • System analysis:

    • EPROM read out

    • Bus protocol examined

    • 9-bit communication

Since a complete re-engineering was not feasible within the time frame, integration was implemented via MESA interface cards.
An alternative microcontroller gateway (similar to our solutions for Bosch CC) would have been possible but was not implemented for project reasons.

Mechanical Adjustments

Mechanical adjustments were also necessary:

  • Original Siemens servomotors:

    • different flange

    • different shaft diameter

  • Measures:

    • Redesign of adapter flanges

    • Replacement of the motor couplings

Thanks to the very good condition of the machine, the high mechanical precision is fully preserved.

Result

This retrofit technically brings the Gildemeister NEF 320 up to the standard of modern machine tools:

  • Open, future-proof control platform

  • Spare part availability without manufacturer dependency

  • Modern EtherCAT drive technology

  • Touch HMI with industrial operation concept

  • Significantly extended machine service life with comparatively low investment costs

Especially for mechanically well-maintained machines, a retrofit is the most economically sensible alternative to a new purchase.