Abstract: In presses such as hydraulic presses used for forming tiles or bricks from ceramic or other materials, a mold box is mounted in alignment with the upper and lower dies. To hold the mold box without keying it to the mold case, a wedging assembly comprises an outer wedge releasably fixed to a wall of the opening and having a vertically angled surface facing inwardly. Next to it is an inner wedge having a vertically angled surface which is brought into contact with the angled surface of the outer wedge. Adjustable securing means such as vertical bolts pass through a vertical passageway in the inner wedge and are screwed into an aligned, threaded passageway in the outer wedge for moving the inner wedge vertically until its translation laterally secures the key-less mold box fast by friction alone against downward thrusts of the upper die.