This is my homemade CNC router. I'm really kind of proud of this thing. I designed and fabricated all the parts myself. The linear bearings are made from roller skate bearings, but in a more complex manner than you see on the CNCzone. The machine is made from aluminum angle and bar, High density Polyurethane, MDF, and some pine tongue and groove for the table. I made it a number of years ago. It can do roughly a 13x 24 area. My knowledge of electronics was limited, so I bought a motor and controller system from Maxnc. That ran about 8 hundred dollars. It came with software to run it. Not a horrible learning curve, but poor documentation for the newbie. I bought a version of BobCad to draw parts and convert to what is called G code, which is the machine language that the system understands.Basically the router moves up/down, left/right/ and back/forth corresponding to the X, Y, and Z axes you would find on a graph.
A line or two of a program looks something like this:
That tells the computer to spin the motors enough to make it move 6.5 inches on the x axis and 12 inches on the y axis. Then a G01z-1.0 would move the cutter down 1 inch into the wood.