Abstract: A roll-hardening machine for crankshafts with hard-rolling tools (2) which each have a hard-rolling roller head (1) and a counter-support roller that are each detachably attached to the ends (17) of appropriate scissors arms (3) by means of two clamping blocks (15) wherein respectively a first of the two clamping blocks (15) is positioned on the front surface (16) of the end (17) of the scissor arm (3) and the second clamping block is located at a right angle to the first (15) on the side surface (16) of this same scissor arm (3) on the tool side, characterized in that the first clamping block (15) is supported on the front surface (16) at the end (17) of the respective scissors arm (3) such that it can slide in the direction of the appropriate hard-rolling tool (1), the hard-rolling roller head (1) is supported moveably at the location of the second clamping block on the scissors arm (3), by having guide grooves on its front surfaces facing the scissors arm (3), wherein prismatic blocks of the scissors arm (