Our goal is to develop a complete and automatic scanning strategy of unknown objects. The paper presents a novel approach to determine the Next Best View for an efficient reconstruction of highly accurate 3D models. Our method is based on the classification of the acquired surfaces into Well Visible and Barely Visible combined with a best view selection algorithm based on mean shift, which avoids unreachable positions. Our approach is applicable to all kinds of range sensors. Test objects are first scanned manually by experts in 3D digitization from the VECTEO company. The comparison of results between manual and automatic scanning shows that our method is very efficient and faster than trained experts. The 3D models are obtained with a strongly reduced number of acquisitions while moving efficiently the ranging device. The results prove the effectiveness and the versatility of our 3D reconstruction approach for industrial applications.