This class was derived entirely from conversion of other groups (mostly of QCF class flat wagons) built on the standard post-war 42'-0" chassis. The conversion programme involved the fitting of extension brackets at each end. Building and disposal of the class is summarised as follows:

1962	23590, 23591, 23600, 23721, 23658, 23667, 23687 ex QCF
1963	23665 ex QCD 23578, 23579, 23581, 23587, 23588, 23589, 23592, 23593, 23594, 23595, 23596, 23597, 23599, 23606, 23609, 23628, 23644, 23649, 23657, 23673, 23679, 23688 ex QCF 23581, 23658, 23687 to QCF
1964	23586, 23650, 23685, 23687 ex QCF 23579 to QCF
1965	23598, 23662, 23678, 23686 ex QCF
1967	23677, 23640 ex QCF
1969	23589, 23673 to QCC 23648 ex QCF
1970	23589, 23673 ex QCC
1972	23589, 23673 to QCC
1979	23685 written off
1980	23595, 23626, 23640, 23644, 23657, 23665 to QCG
1982	23649 to QCG
1983	23596 to QCG
1986	23621 written off
1992	23586, 23587, 23588, 23590-23595, 23597, 23598, 23599, 23600, 23606, 23609, 23620, 23638, 23648, 23650, 23662, 23667, 23677, 23678, 23679, 23686, 23687, 23688 written off

The WAGR outline diagram is shown below.

At least 2 wagons (23644 and 23650) were fitted with bulkheads and mesh sides in later years.