Between 1961 and 1968 a total of eight RB(steel), RB(wooden) and RBT class open wagons were converted to Bulk cement wagons of class RBC. The conversions were carried out over an extended period as follows:

1961	11252 ex RB
1962	11271 ex RB
1963	4126 ex RB (wooden)
1964	768, 11294 ex RB
1965	1521 ex RB
1967	18 ex RB
1968	11183 ex RBT
In 1978 RBC11252 was written off and in 1980 number RBC18 was renumbered RBC98. RBC768 was written off in 1992 with the remainder written off in 1993.

Liveries varied over the years as shown in the illustrations.

WAGR official photo of RBC11294 again, I think, when new (RHWA collection)

The WAGR outline diagram is shown below.