Method and apparatus for cutting lines in work materials

In a method and apparatus for cutting either a single sheet or a lay-up of sheets of material (22) to derive pattern pieces (58) or the like from the material (22), the material is cut segment-by-segment (74,76,84,86,88) by bringing a fresh segment to a cutting station (26) after a preceding segment has been entirely cut. Discontinuities, which may translate into points of non-clean cutting, which might otherwise occur in cut lines (62) as they pass to one segment to another, because of accidental shifting or mispositioning of the material during advancement, are avoided or reduced by acquiring the start and finish X and Y coordinates of an index point (90) on the material (22) and then using such coordinates with the cutting instructions used in the cutting of the subsequent segment, the use of the coordinates being such that accidental shifting or mispositioning of the material is taken into account and compensated for in the cutting of the second segment.