An optical cutting edge locator for a cutting machine having a knife for cutting single or multiple sheets of material comprises a light source, a light-projecting system above the knife for downwardly projecting a beam of light from the light source along a planar surface of the knife generally perpendicular to the material, thereby to cause a shadow to be cast by the cutting edge of the knife and to create a line between a shadow area and a light area on the material in substantially the same plane as the cutting edge. The light-projecting system includes either a plurality of fiber optic transmission lines having light-emitting ends mounted above the knife or an elongated slot above the knife. The plane of the planar surface of the knife generally bisects either the light-emitting ends of the fiber optic transmission lines or the elongated slot so that the beam of light being downwardly projected is split by the planar surface of the knife.

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