Cutting
The result of violent attrition of molten metal on unprotected and unsuitably prepared mould surfaces. When, because of dampness, steam forms more rapidly than it can escape through the vents, it forces its way through the surface and lifts a portion of the mould's skin with it, forming a scab at that place. This by some is improperly termed a "cut" place. Cutting means a forced displacement of the surface caused by undue abrasion, or impact. The former happens when a large quantity of metal is urged over a surface not sufficiently unyielding in its nature to resist it successfully; the latter when such surfaces are subjected to a fall of metal high enough to break them. See SCABBED CASTINGS; CURRENT; GATES; RUNNERS.