In 1912 he travelled to Canada and also visited Paris and Florence, but he returned to Scotland in 1914 as the country readied for war, using his engineering skills to fit out trawlers and drifters for mine-sweeping and other operations.

[citation needed] Together with James Cowie and Archibald McGlashan, Sivell was a founder member of the Glasgow Society of Artists and Sculptors in 1919.

His pupils included Joe Edwards, Taylor Bremner, Gordon Stewart Cammeron,[5] and Alberto Morrocco, who built up a large collection of Sivell's work.

While at Gray's, he undertook a large-scale painting project consisting of larger-than-life murals in a lecture and exhibition hall within the Aberdeen University Union on Gallowgate.

This project involved two of his pupils (Alberto Morrocco and Gordon S Cameron) in an effort that began in 1938 and continued until his retirement in 1953, being interrupted by World War II.

[7] Sivell was sculpted by his friend Benno Schotz, and while photos of this bust exist, its current location and condition are unknown.