As a serious maker, I have several CNC machines, including two 3D printers and a CNC router. But what if I wanted something else, like a laser engraver or a PCB milling machine? So I set off to do just that: build an inexpensive CNC machine that could have many different attachments, all while controlled through a simple interface of G-code.
I started by thinking of a free-wheeled machine that could have an infinite Y-traverse, but it proved to be too cumbersome and inaccurate.
Making the Bed and Y Axis
The bed (Y axis) is comprised of two 500mm or 800mm V-slot rails arranged in parallel. There are four plastic pieces that hold two wheels each, allowing for easy travel of the bed along the rails. I also ran a timing belt across the Y axis under the bed, so that when the Y axis stepper rotates the belt moves.