Cranmer is from the 'Namgis First Nation and was born in Alert Bay in 1927. He learned to carve with traditional carvers Arthur Shaughnessy and Mungo Martin. He worked with Bill Reid on the Haida Village at the UBC Museum of Anthropology in 1959. In the 1960s he helped operate The Talking Stick, a retail outlet for First Nations' work. Cranmer contributed extensively to the construction of the U'mista Cultural Centre in Alert Bay. The carved doors for this centre by Cranmer were exhibited at Expo '70 in Oaska, Japan. He oversaw the production of the Spirit Lodge at Expo '86 in Vancouver. He has acted as a teacher to pass on the traditions. In 1994, the Museum of Anthropology produced an exhibition of Cranmer's paintings and published a book about him entitled Whittling for a Living.