Since CNC machine tools for additive manufacturing, subtractive manufacturing and laser cutting operations have similar design features, it would be of interest to design and build a universal manufacturing / prototyping machine capable of performing all three types of operations. The objective of the current project is to design, build and operate a CNC rapid prototyping machine that can be used alternatively for CNC milling operations, 3D printing and laser cutting. The universal machine will consist of a stage that supports the workpiece and capable of moving along the Y axis of a Cartesian coordinate system, and two piggybacked X and Z axes supporting the tool. The axes will move along two linear slides , each containing two ball bearing blocks . The motion is controlled by NEMA 17 unipolar stepper motors with a step angle of 1.8o per pulse , connected to leadscrews  through flexible couplers . A common tool holder plate designed to hold a spindle  for CNC milling operations, a filament extruder  for 3D printing or a laser  for laser cutting operations will be attached to the X axis. A Smoothieboard controller  will be used to interface the computer to the stepper motors and convert the coded alphanumeric data into train of pulses sent to the stepper motors.
The advantage of the proposed technology consists in its low cost and in its capability to perform a variety of CNC manufacturing operations using a single machine tool.
CNC can be applied to a variety of manufacturing processes including chip forming cutting operations - also called subtractive manufacturing such as milling, turning or drilling, 3D printing - also called additive manufacturing (a form of rapid prototyping), or laser cutting. The common operating feature of all CNC applications is the automated control of the tool (cutter, extruder, laser, etc.) movement relative to the workpiece that is fabricated. As a consequence, most CNC machines share similar features which include a stage (table) supporting the workpiece that can move along two or three piggybacked axes using drive trains and a tool support that can move along one or more axes. The motion of the tool and workpiece are controlled by stepper motors or servomotors connected to the leadscrews or pulleys through coupling mechanisms.