I have retrofit several Gerber Sabre 408 CNC routers with LinuxCNC, and because of this I developed my own drop-in replacement retrofit motherboard. Attached is a photo of the new motherboard, a photo of the original motherboard, and a screenshot of the LinuxCNC software.
The board has all of the same connectors in the same positions with the same names, making it a breeze to install. You do not have to make any modifications to your electrical cabinet nor machine to use this retrofit board! Also be aware that these machines say they require 208V 3-phase, but in reality they will run off 220V single-phase.
Here is list of motherboard features:
- 4x encoder input connectors as the original board had
- 4x Elmo brushed DC servo drive connectors w/ ±10V analog outputs, drive enable signals, and drive fault feedback
- 2x electrically isolated RS-232 / RS-485 transceivers for controlling the OEM Yaskawa / Saftronics variable frequency drive (VFD) that is used with their "high frequency spindle" option
- replicating the original home/limit switch inputs
- replicating the original +24V outputs to drive the contactors in the electrical cabinet that switch the two 120VAC outlets meant for a "dumb" router (for those who don't have the high frequency spindle / VFD) and for a vacuum (dust collector)
- extra probe inputs: one for a tool length probe, another for a workpiece probe. There are jumpers to have each one operate off +24V or +5V, and be NPN or PNP (active high or active low). This means active sensors (inductive, etc.) are supported, as well as simple mechanical switches that close.
- alternative servo axis connectors: DB25 / IDC26 connectors are present that allow hooking up aftermarket servo drives using either analog velocity mode, or step/direction position mode. They have encoder feedback for true closed loop, as well as two isolated outputs (typically "enable" and "alarm reset") as well as two isolated inputs (typically "drive enabled" and "alarm").
- 6x RJ45 connectors for Mesa SmartSerial bus expansion, allowing extra I/O, jog pendants, etc.
- DIN rail mounting holes on the motherboard itself for a convenient place to install any extra I/O modules (SmartSerial interfaced)
Here is an example of a 32-input 16-output Mesa SmartSerial expansion card:
Mesa 7i84 remote field I/O (sourcing outputs)
The kit includes:
- the LinuxCNC retrofit motherboard, with Mesa 7i80HDT FPGA card assembled onto it
- 8x M3 mounting screws (in case the original motherboard screws are missing)
- an HP small form factor PC with power supply AC adapter. The PC runs LinuxCNC perfectly even while browsing the web, and it has built-in WiFi (not added via USB). It will come pre-configured to run the Gerber out-of-the-box.
- optionally: 22" ViewSonic VA2256-MHD LCD, which is 1080p with an extremely wide viewing angle and easy to clean front due to the bezel design
- optionally: VESA monitor arm (for above monitor)
- optionally: wireless mouse & keyboard
You can read more about my kit on this LinuxCNC Forum post:
https://forum.linuxcnc.org/39-pncconf/46987-gerber-408-retrofit?start=20#294504
Please contact me if you are interested in this kit!