Air Constructs with frozen air

If you constructed a structure of frozen gases in just the right way,say with a 3d printer that operated below their freezing points, or by 3d printing a destroyable mold, you could possibly create things made only of gas, that could operate at normal temperatures, using the pressure of the evaporating gas as their source of energy.

For example, you could have a thick structural exterior with openings for warmth flow into frozen "fuel" with high surface area inside, and possibly guide the sublimating gas pressure back outside such that it produced strong enough wind to levitate the object (before it evaporated) and possible press against a user's hand so that they could pick it up without touching it. If successful, they might feel the wind of it when grasping it, rather than its dangerously cold surface.

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