In the late 1920s, Rudolph Lettner was a recreational skier who enjoyed the slopes of the Austrian Alps near his home in Salzburg. Like many skiers of that time, Lettner sustained considerable wear on the edges of his wooden skis due to the abrasion of ice and snow against the ski surface. Lettner, a metal worker by trade, sought to create a solution to the damage caused to his ski edges that would ensure that the skis lasted longer. Lettner fashioned a steel edge that was intended for use on all Alpine skis; Lettner patented his design in 1930.
Lettner's original metal edges were not built-in as part of the ski manufacturing process; the Lettner metal edge was screwed into the framework of the finished ski. While the edges achieved the preservation of the ski surface that Lettner sought, the edges were very sharp and many skiers were fearful of being slashed by the edges through normal usage. Lettner also found that in many types of weather and snow conditions, snow would freeze to the metal edges, impairing the performance of the ski. This problem was also encountered by ski developer Howard Head in his testing of the famous all metal skis that he designed in 1949; the adherence of snow to the steel was ultimately solved through the lamination of the ski surface.
The most enduring legacy of the Lettner metal edges was not the preservation of the wooden ski, but the development of an entirely new ski technique. Lettner discovered that the metal edges permitted a skier to carve into a downhill turn, using a combination of the metal edges skis and a low body position to forcefully cut through the snow for a faster, more aggressive turn. Prior to the advent of the metal edge, skiers tended to turn on top of the surface of the snow. Skiers could also go faster downhill in a forward position as the metal edges permitted the skier to assume a more aggressive forward position on the skis. For these reasons the metal edge permitted a more dynamic style of skiing that was soon adopted by racers in all Alpine disciplines.
It is unknown as to whether Lettner obtained any commercial advantage from his patent.