The technology.

 

The way prehistoric stone was formed — under unimaginable pressure for millions of years — is one of the main reasons for its astonishing properties. It can take enormous compressive loading, but has to be protected against shear stress by wrapping it in carbon fiber. Wrapping stone in laminated carbon fiber by a patented method makes it bendable as well as pressure resistant. This benchmarking discovery by TechnoCarbon Technologies is decisive for future applications.

 

Carbon fiber itself is very light and has a high tensile strength, with a negative coefficient of thermal expansion. The new CFS material therefore offers a unique combination of positive properties: not only enormous compressive strength, but also incredible elasticity and dynamics with high geometric stability — all with the same specific mass as aluminum! And of course stone also has impressive damping characteristics that are ideal for ski construction. Thanks to the new CFS development, they can now be exploited. By damping out vibrations, stone makes zai Spada skis incredibly smooth-running and grippy — a heavenly feeling on the slopes!

 

The stone used in the zai spada is green Rofna-Porphyr gneiss from Andeer in the Rhine headstream valley, Grisons. Gneiss is a form of granite whose structure was altered by high pressures and temperatures. Andeer gneiss incorporates mineral foliations in layers, and locally it is often called simply granite. Completely new techniques are employed in fine-working and stabilizing Andeer gneiss. The stone must comply to one tenth of a millimeter with the ski core geometry, even where it is only 1 millimeter thick. And since the one-piece stone core extends over almost the entire ski length, incredible precision is required that can only be attained on special machines. Stabilizing the stone takes years of know-how that is kept strictly secret. This joint venture between zai and TechnoCarbon Technologies is an exciting challenge to both firms, and also reveals an enormous potential for the future of CFS.