7 model sets, iterating A4 locomotive #4487 built in 1937.

Sir Nigel Gresley was Chief Engineer of the LNER in the 1930s when the 'streamlined' A4 class express passenger steam locomotive was designed and built. The A4 class locomotives were to the same basic design as the earlier A3 with three cylinders, and the same wheels and wheelbase. Design improvements were made to heating surfaces, and to steam admission and exhaust, which resulted in a better running machine. The A4s were built at the Doncaster works of the London and North Eastern Railway, England beginning in June 1935. In all, 35 of this class were built in the period to July 1938.

Hornby Dublo (a brand name of the iconic Meccano Limited, Liverpool) was introduced to the toy buying English public in 1938, with a model of an A4 locomotive, and suitable carriages. The models were made completely of metal, and were designed to run on 3 rail track made up from lithographed sheet metal and plated brass. The locomotive was powered by a 12 volt DC open-framed miniature electric motor. The system was small enough to run on a large table top, and designated OO gauge, the same track gauge as used on the continent under the label HO (half 0). The scale was roughly 1:75.

Details of the 7 sets.

The locomotive body was a pressure-cast zinc alloy moulding, and the tender was made of sheet metal and small castings for buffer and connection parts. Locomotive and tender were painted, and lettering and numbering applied with transfers. Carriages were made of lithographed sheet metal and small castings for bogie and buffer parts.

These were quality models for their time, and produced between 1938 and 1964. Additional carriages were available separately. An unlimited number of the models are still available on the second hand market, in working order. From 1964, the models were available under the 'G and R Wrenn' label, but only in a two rail version. The picture below shows a Hornby Dublo set as you may have viewed it (imagine it new and unmarked) in a toy shop in the late 1940s, or early 1950s. The engine is coloured in the pre-1948 scheme of the LNER, and lettered Sir Nigel Gresley. The box lid and side labels are also shown.


A layout built using Hornby Dublo 3 rail trains and accessories from the 1950s was on display at the 2012 Brisbane Model Train Show. Here is a photo, I apologize for the quality.