Flasks
The Encyclopedia of Founding (1892)
The iron or wooden moulding-boxes in which sand matrices or moulds are formed for the production of castings. When a mould is formed in the floor, only one flask, cope, or top part is needed to cover with, consisting of frame and bars; this may be cast in one piece, or it may be made up of sides, ends, and bars, all separate; in which case the ends and bars must be bolted or wedged in their respective places. In such a cope, stops for guiding-stakes, trunnions for turning over by, and handles or ring-bolts for lifting with, are all that is needed for the complete flask. Lugs and pins added to such a flask would convert it into a cope, only requiring a nowel, or bottom part, to complete a set, being then called a pair of flasks. Intermediate cheeks make it a set of flasks, three-part, four-part, etc., according to the number of cheeks interposed betwixt cope and nowel. By fitting all such flasks to standard templets they become interchangeable, making it a simple matter to fit any kind of job when the cheeks are made of various depths. The business of making small flasks for brass-moulders is now a special one, and the dealers in foundry supplies can furnish them with pouring-holes in any position desired. They are also drilled with standard templets, faces planed, pins turned true and bolted to the lugs with nuts. Being interchangeable, they are readily replaced when necessary. See BAR; FLOOR-MOULDING; STAKES; COPE; TRUNNION; RING-BOLT; LUGS; PINS; NOWEL; CHEEK.
What Has Changed in the Last Century
The vocabulary the 1892 Encyclopedia of Founding sets out has largely survived: sand foundries still speak of the cope on top, the cheek between, and the interchangeable flask drilled to a standard template — though the bottom part it calls the "nowel" is now almost universally the drag in English-speaking shops. What has gone is the wooden flask and the hand-rammed floor mould as the ordinary way of working. High-volume foundries now run automatic green-sand lines, including flaskless machines that ram and eject a continuous string of moulds with no box around them at all, at rates of several hundred an hour. Alongside them sit methods the writer could not have named: investment and lost-foam casting, and sand moulds printed directly by 3D printers with no pattern or flask involved.
Written for this edition, 2026.