Abstract: Apparata and methods are shown and described for converting closed-topped containers, e.g., common aluminum beverage cans and steel food cans, into open-topped containers having open top mouths surrounded by a smooth rounded lip. In a preferred version of the invention, a closed-topped container, e.g., an aluminum can, is inserted within a casing so that its top protrudes outwardly therefrom. A tubular ram having a cutter situated therein is inserted over the can top and rotated with respect to the can to sever the can top from the remainder of the can. The ram is then withdrawn and inverted to reveal an annular bending groove facing the cut upper can sidewall. The ram is then screwed onto the casing to bring the bending groove onto the cut upper can sidewall, thereby bending a rolled lip on the can sidewall. The closed-topped can is thus converted into a cup-like open-topped container.