Abstract: A blanking machine for blanking holes in a sheet of metal in a zigzag fashion comprising a bolster, a pair of rails, fixedly secured to the bolster extending in a direction right angles to the feeding direction of the sheet of metal to be blanked, a lower die set slidably mounted on the rails, a die fixedly secured to the lower die set, an upper die set having a punch mounted thereon opposite the die, the upper and the lower die sets being coupled together, a hydraulic cylinder having a plurality of pressure chambers formed therein, a transmission mechanism connected to a piston rod of the hydraulic cylinder, and a connecting rod for connecting the transmission mechanism to the upper or lower die set.