A method for the manufacturing of circular washers for locking from blanks, a washer having a central hole, a first side comprising a pattern of radially extending teeth and a second side comprising a pattern of radially extending cams. The method is especially comprised in the steps of producing a washer blank having an annular shape; introducing the washer blank into a die assembly for forming a closed shaping space by a lower die portion, an opposing upper die portion, a central die portion and a support piece, the central die portion extending through a washer blank central hole; forming the blank to a washer by mutual movement of said lower and upper die portions; and opening the closed shaping space to extract the formed washer. The invention also relates to a device and a washer.