Abstract: The invention relates to a method for creating clearances in the moulding said of a moulding box, the moulding box being transported into a working area of a robot, a piercing device being brought into a predeterminable position above the moulding box, a piercing implement of the piercing device being moved by a drive predetermined distance in the direction of the moulding said and introduced into the moulding said to a previously defined depth. The invention also relates to a piercing device for creating clearances in the moulding said of a moulding box with at least one connection point at which a mechanical and/or electrical and/or activating connection to a robot is made possible, with a holding device, with at least one drive and with at least one piercing implement, the holding device being connected to the drive and to the at least one connecting point and the at least one piercing implement being movable back and forth along an imaginary longitudinal axis by the at least one drive.