Press tool and method for forming a cutting insert green body having a through hole

A press tool for forming, by compressing a powder, a cutting insert green body having a through hole of length, the press tool comprising

• a cavity arranged to define a compression space corresponding to dimensions of the cutting insert green body;
• and
• a first core rod and a second core rod together forming the through hole, each first and second core rod having a longitudinal extension from a front end to a rear end, and a contact surface at the front end, wherein the first core rod and the second core rod both are longitudinally arranged along a core axis with their respective front ends facing each other, the first core rod and the second core rod both being movably arranged in both directions of the core axis, wherein the first core rod and the second core rod both are movable to a respective press position and to a respective release position, wherein when both the first core rod and the second core rod are in their respective press positions, their respective contact surfaces contact each other inside the compression space, and wherein, when both the first core rod and the second core rod are in their respective release positions, their respective contact surfaces are separated by a distance that is larger than the through hole length, wherein the first core rod includes
• a longitudinally extending rearward portion in form of a base body, which, at a front end, includes a forwardly facing abutment surface, and
• a piston having a rear portion in a form of a longitudinally extending shaft and a front portion in form of a radially protruding head, wherein the contact surface is a front end surface of the head, the head including, at a rear end, a rearwardly facing abutment surface, and wherein the shaft is longitudinally movably arranged in the base body along the core axis, such that the piston is movable to a plurality of extended positions and to a retracted position, in which retracted position the abutment surface of the head abuts against the abutment surface of the base body, and wherein, when both the first core rod and the second core rod are in their respective press positions, the piston is in the retracted position.