 To save money , many sets , particularly interiors , were redresses of existing sets . The Enterprise bridge was reconfigured to stand in for the Grissom , with the chairs reupholstered and the central computer consoles moved to modify the floor plan . An Earth bar and the Klingon medical bay were redresses of the Enterprise sickbay . The Klingon bridge was a set that Nimoy appropriated from another production . Many blinking consoles were rented from a props company rather than being fabricated . The Enterprise bridge itself remained largely unchanged from its appearance in the previous films , though the floor was repainted from black to grey to make it photograph better . The most drastic change was made to Spock 's quarters . Nimoy had felt the previous grey color scheme did not express a Vulcan style , and had it brightened with yellows and oranges . 
