Characterization of cross-country ski base material

Abstract: Cross-country skiing has developed to become one of the most competitive winter sports, where a skier can win by fractions of seconds. Joint efforts between ski technicians and scientist have allowed the development of methodologies to prepare the ski surface, yet much of the knowledge up to date is based on the experience of the technicians.  In this sense, much attention is focused on the ski base, given that the friction at the base is an important factor that will define how fast a ski can glide. Ski base preparation is an extensive procedure, due to the several parameters that have to be taken into account. Much disagreement has risen regarding the best way to optimize the base. Thus, a complete characterization of the ski base can help to provide some clarity on the factors that affect friction.   This work presents the results of the characterization of the ski base through the preparation process by observing and measuring different aspects, using characterization techniques such as LOM, optical profilometry, contact angle, DSC and XCT. The results suggest that the mechanical machining of the surface can influence wax retention and hydrophobicity. Furthermore, it is seen that wax is present after the first waxing step, despite the constant brushing and scraping. No major changes were observed for the crystallinity. Finally, the amount of graphite on the surface was quantified. This is hoped to be helpful for ski technicians and athletes alike to improve the performance of their skis.