Knipex Diagonal Cutter for plastic and other soft materials such as lead The Knipex 7201160SB (carded) Diagonal Cutter is 160mm in length. With an opening spring to relieve strain on the user and a head manufactured from vanadium electric steel which has been forged and oil-hardened. The Knipex diagonal cutters have been specially developed for plastics and other soft materials. Their cutting edges are surface ground. The Cutter is used in plastics production when, for example, plastic moulded parts need to be mechanically separated from sprue after demoulding. The surface ground cutting faces permit the clean, flush disconnection of extruded plastic injection moulds and sprues or sprue residues. The sprue is cut off directly on the moulded part, because the cutting edge runs parallel to the component. In many cases, work steps in plastic injection moulding and other production processes repeat. Anyone who frequently separates sprues from moulded parts therefore appreciates the opening