I have received a number of questions on what makes up a CNC router system.

I have prepared a short PDF file on the mechanical parts of a CNC router.

There are several parts of a CNC router system.

The first part is the mechanical part that does the moving. It usually contains  three axis labeled X, Y and Z.

My designs are for a moving table system, so the X axis moves in and out on a pair of linear rails. The Y axis is mounted on the bridge and moves back and forth.

The Z axis horizontal position is controlled by the Y axis. The Z axis is the axis the moves up and down moving the router bit into the material.

Once you have the mechanical part constructed, you will need something to power the stepper motors. That brings us up to the electrical control box. The electrical control box contains a DC power supply and stepper motor drivers. In addition, my system has a break-out board that separates the signal from the PC parallel port. The break-out board also contains three small power supplies.

Backing up now you will need a PC that will send signals to your control box and stepper motor drivers.  Many of us are using a program called Mach1 or Mach2. The purpose of the PC control program is to read a tool path file and send signals to the stepper motor drivers. The signals (step and direction) are synchronized so that the router will follow the intended path in 2D or 3D.

To create the tool path you will need two more computer programs. The first one would be a CAD program like Autocad or Rhino3D. The Cad program creates the drawing of the part that you want machined. The part can be a flat part (2D) or a 3D model (3D).

The next program would be a CAM program like VisualMill ( www.mecsoft.com ) . The purpose of the CAM program is to take the 2D or 3D file and convert it into a tool path program. The tool path program contains the information that a program like Mach2 needs to control your router. 

All of this may seem complex, but as you work through it, things will start to become clear. Fortunately for many of us, there is a lot of help on the internet. Yahoo has a number of excellent user groups dedicated to helping you better understand the world of CNC.

Once you get bit by the CNC bug, there is no turning back. Once you start making parts that can only be made on a CNC router you will be telling the story to all of your friends.

Bob Campbell
Bob Campbell Designs

"Creative people inspire the rest"