Abstract: A planar magnetron cathode target assembly is formed from a plurality of individual target tiles arranged in end-to-end abutting relationship so as to form a continuous and enclosed length of consumable metal. In use, the individual targets are eroded so as to define a continuous annular track or trough having a curved V-shape or double-convex cross section with the deepest part of the trough being generally intermediate the width of each target tile. At this time, each target tile in the longitudinal rows is severed along the deepest part of the trough and reassembled with the thickets or least eroded parts of the several target segments in transversely abutting relationship. Each of the end tiles is also rotated 180.degree. to position its non-eroded portion in abutting relationship with the endmost severed and reassembled targets.