This is one of my designs for a DIY CNC machine. It is designed to use a Dremel for the spindle although it could be easily adapted for a water cooled 2.2 kw spindle from China for about $500 dollars.
It is not quite done yet, so I won't publish the blueprints, but you will get the first crack at them before they go out anywhere else.
The electronics to power this are the same as a 3D printer. It is cheap and readily available, once I started really digging into how to put this together, I realized it was super easy to set up.
This design uses 9 pieces of laser cut steel plate 4mm thick.
I am also working on a design that will use angle bar, hardware store threaded rod, and other hardware store parts to use as a manual milling machine.
This basic design if it is beefed up could be used to machine steel. By that I mean using water jet cut 1/2 inch steel plate and a better type of linear guide.
Btw this was drawn in that free DesignSpark program I told you about earlier.