South Australian Railways 'RX' class 4-6-0

Designed by Chief Mechanical Engineer Thomas S. Roberts.
Built at various locations 1913-1916 by the following:-
North British Locomotive Co. Glasgow. James Martin and Co. Gawler.
Walkers Ltd. Queensland. Islington Railway Workshops.
Sixteen fitted with Superheaters 1925-1946.

CYLINDERS (2) 18 ins x 24 ins (457mm x 610mm)
COUPLED WHEEL DIAMETER 54 ins (1,372mm)
TOTAL HEATING SURFACE 1,437 square feet (133.5m²)
(including superheater)
GRATE AREA 20.3 square feet (1.89m²)
BOILER PRESSURE 175 PSI (1,206.62kpa)
TRACTIVE EFFORT 21,420 lbs (9,716.11kg)
TOTAL WEIGHT 88.5 tons (89.92 tonnes)
LENGTH OVERALL 57 feet 11¾ ins (17,672mm)

The RX was a development of an earlier 4-6-0 'Ten Wheeler' type, the R class, introduced by CME William Thow in 1895. These locomotives were extensively rebuilt and had new 'Belpair' boilers fitted in the period 1899-1913. They were reclassified and proved to be so successful that a further fifty four were built.

The RX's were to become South Australia's most widely used locomotive type being employed on most of the major passenger and freight movements until the introduction of Webb's big engines in 1926.

They continued to roam all over the broad gauge system after this period, picking up anything from suburban passenger, freight transfer and shunting duties to hauling all sorts of mixed traffic over the lighter parts of the secondary network.

A number of the engines were scrapped in the 1930's, with the survivors being overhauled and continuing in service until the late 1960's. A few remain today in various parks and playgrounds around the State as static reminders of a past era. Number 93 is on display at the National Railway Museum, Port Adelaide, and numbers 207 and 224 are in service with the Steamranger Tourist Railway at Mount Barker.