In 1931, Colvig joined Walt Disney Productions as a writer, also providing sound effects, including the barks for Pluto the Pup. The following year he began voicing Goofy, originally known as Dippy Dawg. Other notable characters he voiced include Practical Pig, the pig that built the "house of bricks" in the Disney short "Three Little Pigs", and both Sleepy (originally to be voiced by Sterling Holloway) and Grumpy in "Snow White and the Seven Dwarfs". He also provided Ichabod Crane's screams in "The Adventures of Ichabod and Mr. Toad" in 1949. He directed (along with Erdman Penner and Walt Pfeiffer) the 1937 Mickey Mouse short "Mickey's Amateurs".