Why

I was given a Denford CNC mill that is in amazing condition.

It was controlled through a proprietary software that is no longer maintained. Instead of reverse engineering the serial protocol that interfaces to the old controller, I decided to make a new controller.

How

The new controller is based on GRBL and sits on the 96 way header. It allows for a microcontroller to be plugged in and run the machine.

All inputs are protected with clamping diodes to protect against voltage spikes. Additionally there is an RC filter which debounces the switches and a buffer.

Because I don't have a computer near my CNC, I decided to add the option to add a Bluetooth transceiver to the board. This lets me connect to it using my phone and this works amazingly well. I do all the homing and Gcode streaming through an app called GRBL Controller. Everything works great! The app also allows streaming Gcode over USB and there are many other Gcode senders.

Micro Turn users

If you have a lathe that has an encoder mounted to the spindle you will not be able to use this with the board to do threading. GRBL does not have the ability to read the encoder and sync the X and Y axis with it. If your lathe does not have an encoder it couldn't do threading anyway. Profile cutting still works!

What's included

A fully tested, fully assembled Denford CNC GRBL Controller board.

Optional:

The blue micro controller comes programmed with the latest version of GRBL and preconfigured with the micro-mill settings that should be a good starting point. You may source your own and program / configure it yourself if you prefer.

The Bluetooth module is configured to be compatible with GRBL. It can be very hard to source these as there are many manufactures and configuration is highly varied so I don't recommend sourcing your own.

New in V0.0.3

• Added spindle enable hardware that converts the spindle PWM signal to switch the 24V spindle enable relay
• Added direction and coolant hardware to control relays.

If you have any questions please contact me!