Tunnard studied at the Royal College of Art in London and worked as a textile designer early in his career. On moving to Cornwall in 1930, he devoted increasing amounts of time to painting. During the Second World War Tunnard served as a coastguard and his paintings of this period show a preoccupation with navigational equipment, weather effects and distant horizons. Influenced by the work of Miró, Klee, and British abstract artists, Tunnard developed a distinctive style which contained references to electrical appliances such as radars and radios. An accomplished jazz musician, the lines stretched across his pictures refer both to futuristic electrical equipment and stringed instruments. He participated in several Surrealist exhibitions but never officially joined the group.