A rather simple system this time : slip joint. We don’t really need a lock if we mostly use a knife for food.
Since carbon fiber is a strong material, we could skip the use of steel liners, making the whole stuff a lot lighter.
Another original feature, we designed a new composite type of spring, assembled like a sandwich around a thin layer of G10 (glass fiber).
Without harming the functionality, we achieved to save about a third of the metal weight. Even more, we chose titanium screws on the pivot, lighter than steel.