The ship displaces 1,406 gross tons, is in length, with a beam of, and a draught of .[1] Top speed was .[1] In naval service, the ship was armed with a QF 12-pounder 12 cwt naval gun, supplemented by five Oerlikon 20 mm cannons and two Vickers machine guns.[1]
Cape Leeuwin was built in 1924 for the lighthouse service.[2] The ship was laid down at Cockatoo Island Dockyard on 15 July 1924, and launched on 10 December 1924.[3]
She was requisitioned for service with the RAN from the Queensland Department of Commerce in October 1941 and commissioned into the Navy on 27 August 1943. Her peacetime captain, Noel Buxton, stayed with the ship throughout her naval service and received the rank of Lieutenant.[4]
From August 1943, Cape Leeuwin was used to lay buoys and service lights along the coast of Queensland and in the South-West Pacific. She laid buoys and beacons between Milne Bay and Hollandia in New Guinea. From late 1944, she served in the Philippines Campaign, and established navigation aids at Leyte, Mindoro, Subic Bay and Manila. As part of these operations, she was the first Australian ship to enter Manila Bay after the Battle of Manila. In July 1945, she and established lighthouses in the Moluccas which reopened a route between Darwin and Morotai.[5]
After the war, Cape Leeuwin was decommissioned from the RAN and returned to her owners on 12 December 1945. She continued in Australian service until 1963 when she was paid off and sold to a company in Asia, which named her Ruby.