Abstract: A relatively hard sand cake, containing a metal casting cavity, is formed in a flask comprising cope and drag frame sections by filling and compacting sand in the drag against the drag half of a cavity-forming pattern, then arranging the drag with the cavity opening upwards, applying the cope upon the drag and filling and compacting sand in the cope against the cope half of the cavity-forming pattern. The sand-filled cope is lifted from the drag for removal of the pattern and is re-applied to form the casting cavity in the sand cake. Next, selected wall corner joints of both the cope and the drag frames are separated and opened to laterally expand the walls of the frames away from the sand cake surfaces. This releases the sand cake from the cope and drag so that it may be removed from the flask for later casting molten metal in its casting cavity. At least two of the corners of each of the cope and drag frames include a separate corner piece against which the adjacent ends of the frame walls are abutted.

Abstract: A flaskless sand mold is formed in vertically aligned, sand-filled cope and drag flasks having a pattern board arranged between them so that pattern portions mounted upon the board extend upwardly into the cope and downwardly into the drag. The sand in the drag flask is supported upon a vertically guided platen which covers the bottom of the drag flask, and the cope is covered with a squeeze plate. The sand fillings are compressed against the pattern board and the pattern portions by the platen and squeeze plate to form compacted cope and drag sand molds with aligned cavities. Then the platen, supporting the drag sand mold, is lowered a short distance while the drag flask is held immovably against the cope flask. Thereafter, while the platen, with the drag sand mold, continues to lower, the drag frame is simultaneously lowered into a rest position upon a track-like support.

Abstract: A relatively hard sand cake, containing a metal casting cavity, is formed in a flask comprising cope and drag frame sections by filling and compacting sand in the drag against the drag half of a cavity-forming pattern, then arranging the drag with the cavity opening upwards, applying the cope upon the drag and filling and compacting sand in the cope against the cope half of the cavity-forming pattern. The sand-filled cope is lifted from the drag for removal of the pattern and is re-applied to form the casting cavity in the sand cake. Next, selected wall corner joints of both the cope and the drag frames are separated and opened to laterally expand the walls of the frames away from the sand cake surfaces. This releases the sand cake from the cope and drag so that it may be removed from the flask for later casting molten metal in its casting cavity. At least two of the corners of each of the cope and drag frames include a separate corner piece against which the adjacent ends of the frame walls are abutted.