All zai skis have cores made from bonded cedarwood staves. Cedarwood is expensive and complex to work with, but it is also incredibly light, offers excellent resilience (it returns to its original shape after bending), and has a consistent grain that resists warp.
The cedarwood cores of zai spada and giubileum skis have integrated CFS® (carbon fibre stone) to provide extra damping.
This plastic fibre is 60% stronger in relation to its weight than carbon fibre, and up to 15 times stronger than steel. It is also extremely light and highly resistant to abrasion. Unlike other materials it does not become brittle when exposed to low temperatures. zai is the world’s only ski manufacturer to use this highly sophisticated material.
When you ride a zai ski, you are riding the best high-speed race base in the world.
zai bases are nano-coated, pre-impregnated with wax and manufactured with a high graphite content, making them exceptionally fast and durable.
To further improve quality and performance, zai employs specialist grinding techniques to ensure a base finish that is unsurpassed. Our high-precision stone wheel grinding machines deliver a much more controlled grind than conventional belt-sanding devices.
During service, zai skis are treated with infrared heat to ensure a deeper penetration of wax, ensuring optimum performance season after season.
Vulcanised natural rubber is an amazing material for ski-making, being both durable and scratch-resistant, and possessing excellent damping qualities.
Applied to the upper surface of a ski, natural rubber helps to absorb impacts when riding on rough or icy snow. Not only does this make for a smoother ride, it’s also kinder to your knees.
Best of all, natural rubber can be re-worked to pristine condition. So when it comes time to service your zai ski, it will be returned to you looking like new. zai uses only the very best quality natural rubber - the surface of a spada ski costs around the same as some professional racing skis. This, and the technical challenges involved with working with it, is why zai is the first and only ski brand in the world to use this incredible material.
zai is the only ski-maker to build its skis with stainless steel upper edges. The hardened HRC 50 steel we use for this is extremely rugged and resistant to corrosion. Steel upper edges protect the ski against bumps and knocks, and can be re-worked to as-new condition during service.
We also use stainless steel in the upper surface designs of some zai skis. For this we use high-grade spring steel, the same used in the manufacture of fine Swiss watches.
Spring steel has a high yield strength, meaning it always returns to its original shape after bending. This is one of the reasons why zai skis maintain their torsion so much better than other skis.
zai uses pre-impregnated UD (unidirectional) endless carbon fibres in an uncured thermoset plastic matrix. The fibres are applied to the ski by hand and in varying thicknesses, allowing tension to be precisely controlled at strategic points.
The ‘pre-pregs’ are then heat-and-pressure cured during the pressing process, resulting in an extremely strong, lightweight ski structure with excellent torsion dynamics.
Because zai ski designs are arrived at through repeated real-world testing (as opposed to being computer-generated) various thicknesses and arrangements of carbon fibres can be tried during the prototype phase. Only when exactly the right combination and placement of carbon fibres has been achieved is a ski approved for production.