Abstract: A mold battery with provisions for separating one mold member from another by both rotating away and also translating away. A mold member comprises two wheels resting on two rails and a lower roller. While the mold member is rotated to an open angle stopped by the lower roller contacting a stop surface, yet the mold member can also be translated away by rolling along the rails. When joining mold members, a freedom of movement is provided which improves the seal. One embodiment comprises parallel guidance by wheels fixed on a common axle and turning in unison. One embodiment substitutes a fixed pin for the lower roller.