Crandall's earliest art employment was painting signs on storefront windows, before becoming general art assistant drawing maps and supporting material at Newspaper Enterprise Association (NEA) syndicate. He sought work in New York City and Philadelphia as a magazine illustrator and found some work for a children's book publisher.

In 1939, Crandall started with the Eisner and Iger Studio. His earliest work was published by Quality, including the Ray (Smash Comics), Doll Man (Feature Comics) and Firebrand (Police Comics), which he co-created. He provided other early work for Fiction House and Atlas/Marvel, where he inked Jack Kirby on early Captain America stories. For Quality, he drew Captain Triumph (Crack Comics). In 1942 Crandall began his long run on Blackhawk (Military Comics, Modern Comics and Blackhawk), which continued until 1953.

in 1953 Crandall became a key artist at EC Comics until the company closed due to the mid-fifties anti-comics panic. He subsequently freelanced for Atlas, Marvel and Gilberton (Classics Illustrated).

From around 1960 until 1972, Crandall worked on covers and stories for the catholic schools comic Treasure Chest. He also illustrated Edgar Rice Burroughs' novels (1964, Canaveral Press), superhero-espionage stories for Tower, and science fiction for King's Flash Gordon comics.

In 1965 Crandall started contributing to Warren, beginning with Blazing Combat. Until 1973, he provided many stories for Creepy and Eerie, with just one in Vampirella (the first issue).

Suffering health problems, Crandall left the comics industry in 1974. He suffered a stroke and spent the rest of his life in a nursing home.