Methods for making a container, and related systems

A method for making a container, the method comprising:

• forming a first cavity of a container by shaping an inner wall so that a first surface of the inner wall defines the first cavity;
• forming a second cavity of the container by shaping an outer wall so that a third surface of the outer wall surrounds a second surface of the inner wall such that together the third and second surfaces define the second cavity;
• connecting the inner and outer walls together;
• forming a hole through the outer wall to expose the second cavity to the outside ambient environment;
• applying an enamel coating on at least one of the following:
• the first surface of the inner wall and a fourth surface of the outer wall that is exposed to the outside ambient environment, while preventing the enamel coating from being deposited in the hole;
• wherein before applying the enamel coating, temporarily sealing the second cavity to isolate the second cavity from the ambient environment outside of the outer wall;
• heating the container to glaze the enamel coating and fix the coating to the one or more surfaces;
• after the enamel is glazed, removing air from the second cavity;
• and
• while the air is removed from the second cavity, sealing the second cavity so that the pressure inside the second cavity is less than the pressure in the outside ambient environment.