Flexible manufacturing systems (FMS) enable production of various products in smaller series. Fully automated and computer controled production process is integrated for more complex FMS 's. Usualy, CNC machining centers are used as a machining tools within FMS. Introducing an industrial robot as a primary machining tool into FMS 's is considerably a new way of a system design approach. The application is demonstrated on the example of upper cover of a violin. Two different robotic systems were tested. Two-robotic system has positioning and machining robot programmed by Robotstudio graphical interface which does not support of making toolpaths out of surfaces from a CAD model for CNC milling. A single control module is processing 2 robots with 12 degrees of freedom to obtain fully coordinated and syncronized movements of two robots. The other system is a single robot cell with machining table. We applied highly advanced CAM technology for programming to simplify the whole process. Other technological parameters are easy to set - such as non cutting moves, engaging to and retracting from material, etc. Also verification and simulation of toolpath processing is taking place for better visualization of the final product. We produced upper violin cover by both systems to show, that not only highly advanced industrial robots with similar mechanical characteristics are enough, to achieve the desired machining quality. A proper use of right software for programming is necessary, to utilize all advanced characteristics, of any mechanical equipment, to obtain most efficient final product. In our case a single-robotic system gave us better final result.