No. 9642 is a welcome addition to the GWR fleet. Not only did the type regularly work over the line at one time, it is also useful and economical, and well able to deal with the railway's trains. It is more powerful than 6412, the similar pannier tank locomotive that has visited from the West Somerset Railway from time to time.

The engine is expected to be delivered during early April from its present home, the Dean Forest Railway. No. 9642 has a few months remaining on its boiler certificate after expiry of which Andrew expects to remove the locomotive for overhaul away from the line.

The 57xx class was the most numerous of any class on the GWR (and indeed one of the most numerous in the UK) with a total fleet of 863 engines. The first was introduced in 1929 as a development of the 2721 class developed during the previous century. The engines were primarily intended for light goods and shunting, proving extremely reliable and were also useful for light passenger services. Production continued in batches until soon after nationalisation, the last being turned out in 1949.

Many were built by outside contractors such as North British, Bagnall, Kerr Stuart, Yorkshire Engine, Armstrong Whitworth and Beyer Peacock as well as at Swindon which is where no. 9642 was completed in 1945. The very few changes to the class as production progressed were mainly cosmetic, such as improvement of the cab. The only exception was a small number built with condensing equipment to work over the Metropolitan underground line conveying meat traffic to Smithfield market. Also, some members of the 57xx class were equipped with distinctive chimney-top spark arrestors for operation at military sites.

12 members of the class survived into preservation - a number of them via London Transport and the National Coal Board, both bodies continuing to employ them long after the demise of their classmates on the main line.

No 9642's first allocation in 1945 was at  Weymouth where it remained for several years, going on later to Bridport. Its final allocation was Old Oak Common in London from where it was withdrawn in 1964 and the following year consigned to the Hayes scrapyard at Brigend. However, rather than being cut up it was used to shunt less fortunate locomotives that arrived for scrapping. Bought in 1968 by the South Wales Pannier Group it moved to Maesteg Colliery where it worked coal traffic from time to time, then going on to the Swansea Vale Railway. It finally moved to the Dean Forest Railway in 1998. The locomotive is finished in British Railways black livery.

The locomotive weighs 49 tons and operates at a boiler pressure of 200 lb/sq.in. It has two inside cylinders of 17½  inches bore by 24 inches stroke, driving 4ft 7 ½ in. diameter driving wheels.

The locomotive is currently undergoing overhaul away from the GWR.