This 4-head CNC welding machine eliminates the welding bead from the corner and allows users to weld profiles with glass or a closing panel already inserted inside the switchboard. This unique machine performs perfect welding guaranteeing flat and homogeneous surfaces also with profiles that, instead of the metal reinforcement, have inside them non-weldable products such as fiberglass, aluminum or other components. The CNC allows welding profiles coated with any type of film or foil.