Press die set and press machine for driving it

A press die set having a top side, a bottom side, a thick plate punch located at the top side, a thick plate die holder located at the bottom side, a hollow cylindrical guide bush mounted on the punch holder, a columnar guide post vertically mounted on the die holder, a cylindrical retainer having an outer surface which abuts an inner surface of the guide bush, the guide post being movable within a hollow interior of the retainer and within a hollow interior of the guide bush so that the guide bush, retainer and guide post guide smooth vertical movement of the punch holder parallel to the die holder, the press die set comprising first right angle grooves formed on an outer surface of the guide post parallel to a longitudinal axis of the guide post, the first right angle grooves including two planes which are at 90 degrees to one another, first planes formed on an outer surface of the guide post parallel to the longitudinal axis of the guide post and perpendicular to a radius of the guide post, second right angle grooves formed on the inner surface of the guide bush parallel to a longitudinal axis of the guide bush, the second right angle grooves including first and second planes which are at 90 degrees to one another, and second planes formed on the inner surface of the guide bush parallel to the longitudinal axis of the guide bush and perpendicular to a radius of the guide bush, wherein when the guide post moves within the hollow portion of the guide bush, the first right angle grooves are aligned with the second right angle grooves, the first planes are aligned with the second planes, cross roller bearings are positioned between the first right angle grooves and the second right angle grooves, and plain roller bearings are positioned between the first planes and the second planes.