Knock off is the process of removing the gates and risers from the intended casting. Some foundries use sledge hammers or throw the castings against an object. The Dotson Company uses wedges, much like "jaws of life" paramedics use to extract car crash victims. The hydraulic jaws separate the two pieces of metal. The benefits are two fold. Reduced hand and finger injuries and, reduced damage to castings resulting in fewer scrap returns.
