PURPOSE: To manufacture plates of precise dimensional accuracy with high productivity, by continuously feeding long strips of lead alloy sheets between a pair of rotary cutter and expanding toward the transverse direction holding both edges.

CONSTITUTION: An upper rotor 1 with blade group 3G and a lower rotor 2 with blade group 4G are rotated with an identical speed reversely each other by engaging gears 5, 6. A long strip of lead alloy sheet 10 is continuously passed between a pair of rotary cutter to form zig-zag projections in the vertical direction to the plane of the strip. Pawls 14 of chains 13, 17 are engaged on both ends of the strip 10, and the chains 13, 17 are drived with sprockets 15, 16 and 18, 19. Thus the strip 10 is expanded toward transverse direction as it proceeds to form an expanded grid with desired width. Then paste is filled, and it is cut into a prescribed shape to manufacture plates.