Machine for the production of sand moulds comprising a machine structure with a moulding chamber (3), a front plate (1) and a rear plate (2). The front plate (2) and rear plate (3) are arranged for pressing sand within said moulding chamber so as to form a sand mould, and are arranged for receiving respective pattern plates (200) for providing front and rear surfaces of the sand mould with corresponding patterns. The machine further comprises a robot arm (6) arranged for replacing the pattern plates (200), said robot arm being (6) attached to the machine structure, such as to a side (101) of the machine structure.