Molds for continuous casting are made or improved by using a blank or a mold of tubular configuration made of copper or a copper alloy and placing the same onto a mandrel having a cross section deviating from a rectangular, round or square shaped cross section, the tube or the mold is forced onto the mandrel under exertion of force, the mandrel being subsequently removed from the then completed mold. The tubular blank may be prepared to have comparable geometry.
