William Schallert was paid $250 for two days' work.
Herbert L. Strock got in trouble with the Director's Guild for combining his directing and editing credits.
As of April 2005, only one complete dual-projector stereoscopic 3-D print is known to exist anywhere in the world. The Left and Right prints do not match: the color is severely faded on one side, but the film is still viewable in 3-D.
Director Herbert L. Strock had very poor vision in one eye and consequently was unable to properly gauge how the 3-D effects were, and had to rely on others to tell him. Coincidentially, André De Toth, who directed House of Wax, arguably the most famous 3-D film, only had one eye and could not see the 3-D effects at all.
Shot in 3D, but released mainly in regular 2D.
The centrifuge scene was filmed at USC. The actors became sick and were replaced by dummies.
The Hoover Dam's turbines were photographed on glass to provide projected backgrounds to some of the lab scenes.
The robots Gog and Magog were operated by midgets.
The shooting schedule was fifteen days on two sets at Hal Roach Studios, with exteriors at George AFB (Victorville).