Construction started on a new line which went from Kalgoorlie to Port Augusta; however a need for more motive power was required and so the New South Wales Government Railways started negotiating with the Commonwealth Railways.

The NSWGR had introduced their Q Class in 1880 originally as 4-4-0 side tank engines but due to excessive axle loads they were converted by the NSWGR into tender engines with 6 wheel tenders.

All six locomotives were given automatic couplers prior to entering service but all retained their original NSWGR number.

In 1913 and 1914 the class had many problems with cracking gauge glasses and tubes blowing which slowed the progress of the construction of the Trans-Australian Line.

Many more problems followed such as broken stays, side rod brasses, axle box brasses and the need for many of the class to be re-tubed this resulted in most of that class spending a lot of time in the workshops at Port Augusta.