0-6-4 Steam Locomotives in Great Britain

Class L (Locobase 20172)

Data from "Mineral Traffic Engine, Barry Railway", Engineer, Volume 118 (4 December 1914), p. 531; and "0-6-4 Tank Locomotive, Barry Ry", Locomotive Magazine, Volume XXI [21], No 269 (15 January 1915).. See also "John Auld" on John Speller's Web Pages - GWR Narrow Gauge at [], last accessed 8 April 2017. Works numbers were 3038-3047 in 1914.

John Auld, says John Speller, was "one of the unsung heroes of twentieth-century locomotive design" chiefly for his behind-the-scenes work on Great Western Railway locomotives such as the Gauge and Manor Ten-wheeler designs of the 1930s. (Collett was increasingly disabled by a deep depression that followed the death of his wife.)

Before those days, however, Auld was the Barry's last Chief Mechanical Engineer, serving from 1909 to the 1923 Grouping. His only new design was this large, heavy, and powerful locomotive. "The whole of the drawings for the engines were prepared at Barry", says Engineer's report", under the supervision of Mr. J Auld."

It was not unreasonable for the Engineer report to look at the weights and axle loadings and remark that the Barry had "gone about a far with this class as is possible." The high loadings resulted from a tradeoff in which main-line traffic requirements were better served "by handling a small train smartly than by loading the trains up to what would be required from a heavy eight-coupled engine". The LM reported that the design's smokebox was designed to accept a superheater and balanced slide valves. The superheater was never installed.

The entire class was taken into the GWR, but scrapped only three years later. Sources cannot say for sure why such new locomotives were dismantled, but Wikipedia describes a design fault in the trailing truck that led to derailments when the locomotives backed into sidings.