There are two extreme positions related to the wear and life time of ski base structures existing next to each other.
First we need to define what is the ski base structure for the purpose of this article?
Ski base structure is any type of stone-grinded structure for the purpose of this article. We do not question that also other manufacturing methods exist to produce ski base structures as e.g. imprinting, belt-grinding, rilling... For us these methods are - however - so unstable and create so varied results that we do not want to discuss them here.
Stone-grinding
If a ski base is stone-grinded, old structures, small defects and oxidated or thermally damaged layer of the ski base are removed first. Normally a few tens of micrometers are removed in this preparation steps.
In the second step the ski base is flattened with a very fine stone to achieve the best structuring result. In the last step the required structure is grinded in many movements depending on the shape, width and depth of the selected structure. Multiple structures are not considered here...
Best performance of stone-grinded ski base
If competition skis are stone-grinded, they need to pass another long trip before they achieve the best performance...
First the ski base needs to be cleaned to remove cooling and greasing agents, grinding residues and dirt. Then the ski base needs to be waxed several times to clean the cavities inside the ski base. After waxing, ironing, scrapping off excess wax and brushing the skis need to be used on - if possible - fresh crystalline clean and abrasive snow to remove the “unwanted” hair and homogenise the ski base surface.
Here we are already touching our main topic slowly...
Ski base wear
Crystalline cold snow is abrasive and can remove the unwanted hair which is the side effect of the grinding process where molecular chains of polyenthylen are cut and material is removed to create grooves of different shapes. If unwanted technological hair can be removed by abrasive snow, it means automatically that also “wanted” hair of the ski base is subject of abrasion and removal.
If both “unwanted” and “wanted” hair of the ski base is subject of abrasion, it means automatically that ski base wears when used. The more abrasive the snow condtions are, the faster the ski base wears off.
Two contradicting positions
Position I.
Even if ski base structure is protected by ski wax which penetrates inside the ski base, the ski base and the structure on its TOP wears quite fast. The optimal gliding features of a specific structure are less than ca. 100 km on abrasive snow. In other words: after ca. 100 km of use on abrasive snow the structre is worn so significantly that grinded structure loses its optimal gliding features.
Position II.
If skis with a specific ski base structure performes optimally for certain snow and weather conditions, they need to be protected with ski wax application but never re-grinded. Even if the ski base structure wears slightly after each use, the optimal conditions should not be changed. Re-grinding will never restore the original quality.
What do you think, what is true and what is superstition only?