The final quality of machining is directly a function of the type of machine used. The geometrical and micro quality geometrical of finished surface are one of the principal goals of machining. During the operation of turning, in particular, the elastic behavior of the pin controls the surface quality machined. To say that the rigidity of the machine must be largest possible is not sufficient. The design of the axes of movement of the machine must take account of the effects static, kinematics, dynamic of the mass. The rigidity and the conditions of maintenance by the stages must be qualified in comparison with the results sought in term of machined surface quality. To characterize the effect of the vibrations of the machine tools on the quality of the machined surfaces a study was undertaken on two different lathes, a conventional turn and a turn with numerical control. The results of roughness show that the machine tool exploits a great role the machined surface quality. The rigidity of the machine and its capacities damping are prevalent factors to have a good surface quality. To this end the choice of a thing rigid and damping tool is essential for any trial run and any industrial machining in series.