There are several times when we give ourselves a paper cut while opening a delivery box or a book. A resourceful knife maker from Japan has demonstrated that these papercuts can be worse if you turn that cardboard into a razor-sharp chef’s knife. The process involves soaking the cardboard in water and folding it over on itself repeatedly. Then squeeze out all the moisture, pounding it flat and try to make the cardboard as dry and stiff as possible.
No liquid plastic resin is added as stiffener but at one point the extra part of cardboard is shredded, soaked and boiled to extract all the glues which are holding it together. The cardboard blade was then soaked in to improve its rigidity. The final knife can easily slice and dice the cooking items in your kitchen.