Device for shortening translucent multilateral plate material

A device for cutting plate material, comprising two knives lying substantially in a common plane, a first of said knives being rotatable about a first axis and a second of said knives being rotatable about a second axis substantially parallel to the first axis, first support means on one side of said common plane for supporting the plate material, said support means defining a support plane which is substantially orthogonal to said common plane of said knives, both of said axes lying in a plane that forms an acute angle with said support plane said knives having outer peripheries which overlap each other when viewed in a direction generally perpendicular to said first and second axes and generally along said support plane, a second support means disposed on an opposite side of said common plane with respect to said first support means, each of said first and second support means having a respective support surface for supporting said plate material, said support surfaces forming a small angle with each other whose vertex is substantially in said common plane of said knives.