Vibration measurement is one of the most widely used indirect methods of tool condition monitring, but vibration signal features may be affected by overhang lenght. In turning process, it is known that for the best overall machining results, tool overhang should be kept to a minimum. However, a longer tool overhang may be required depending on the geometry of the workpiece and in situations such as internal turning process. The long overhang increases vibration. In this paper the relations between tool overhang and the most commonly used signal features is investigated