Hi there!
I am building a 3 axis, cartesian mill. Approx 450 x 450 x 300 mm working volume.
I am expecting that it will mill wood & plastic, and hope that it will do aluminium too.
Thus far have frame and bulk of y axis built and am playing around with tinyg and software. I have written a very modest interface using node.js to allow control from a browser. I plan to use an RPi as controller. I will post code once it is fit for public viewing 😉
Hope to expand to A axis & DC brushless spindle (currently a handheld router) once complete.
VERY much liking the JSON i/f  — great work guys.
Andy