1. A method for making a mold of an amputation stump, the method comprising:inserting the amputation stump into a liner of a molding aid, the liner having a longitudinal direction, a circumference, and an expansion coupling;
positioning a molding material between the liner and the amputation stump;
positioning a release layer or release film between the liner and the molding material;
lengthening the liner along the longitudinal direction after insertion of the amputation stump to reduce the circumference and shape the molding material.