I've been working on another component to this project. To control the CNC mill I'm building a controller with two rotary encoders for manual control of the mill. The jog wheel controller uses only a single Arduino UNO to read the encoders as well as emulating a USB HID Keyboard to pass the control movements to the CNC control computer. If you'd like more details or to see the code, then check out the separate project page.
I've decided to experiment with the ESP32's RMT controller for generating step pulses.
The technique has already been explored over at buildlog.net blog and it looks really promising. I want to see if this will be a practical method for precision step pulse control in MicroPython. I'll write more about this once I've gotten MicroPython on the ESP32 Wrover to control these shiny new gecko drives.
A couple of days ago my grizzly 2hp spindle motor let out it's magic smoke. So now I'm waiting on delivery of a new 3 phase motor + variable frequency drive to power it. This will allow me to have better control of the spindle speed and I planned to upgrade eventually, however, I had hoped to avoid the cost until much later in the project.
While I'm waiting for the new motor + VFD, I plan to install the ballscrew for the table X-axis, which will replace the ACME screw, enabling smoother table movement with less friction and much less backlash than the crappy OEM lead screws.
I should have a decent amount of time to work on this project over the holiday as I have a week of vacation from work. I'll try to post another update next week.
I found a cad model of a very similar mill, the RF45, I believe that grizzly's mill is built on the same castings. You can check out the model which I have shared on the online cad app OnShape: RF45 Model