"Other modern features included SKF roller bearings on all axles and the innovative, lightweight SCOA-P type driving wheels, which were specially developed for the R class by the Steel Company of Australia.An order for 20 locomotives was placed with the VR's Newport Workshops in 1946, but remained unfulfilled for years as shortages of steel and manpower saw other projects (such as the overhaul of badly run-down infrastructure and the building of extra X class goods locomotives) given precedence.