Following the adoptions of the flat-topped Belpaire firebox design the GWR revised it's saddle tank engines to eliminate the tank over the firebox, producing a full-length pannier tank design to provide adequate water capacity. Many of the hundreds of saddle tank engines the GWR owned were converted to pannier tanks, but by mid-1920s many of these engines were reaching the end of their working lives and new locomotives were going to be required. Under Chief Mechanical Engineer C B Collett the existing Dean 2721 class design from the late 1890s was fully updated, though some older details remained including the traditional cab style showing it's original open back roof with separate with rear spectacle plate added.
Needing the locomotives quickly the GWR placed orders with several of the private locomotive builders with deliveries commencing in 1929. 300 locomotive had been placed in service by the end of 1931 with contributions from:
North British Locomotive Co (Glasgow) 100 locomotives, 5700-5749 & 7725-7774 (7752, 7754 & 7760 preserved)
Kerr, Stuart & Co (Stoke) 25 locomotives 7700-7724 (7714 & 7715 preserved)
W G Bagnall Ltd (Stafford) 50 locomotives 6700-6724 & 8725-8749
Yorkshire Engine Co (Sheffield) 25 locomotives 6725-6749
Armstrong Whitworth & Co (Newcastle) 25 locomotives 7775-7799
Beyer Peacock (Manchester) 25 locomotives 8700-8724
The GWRs own Swindon works contributed just 50 locomotives, numbers 5750-5799! (5764, 5775 & 5786 preserved)
Some of these private builders contributed one of the most noticeable variations in this 'original' 57xx series. While North British, Armstrong Whitworth and Beyer Peacock had adopted the welding techniques Swindon was using to construct the pannier tanks the 100 locomotives supplied by Bagnall, Kerr, Stuart and Yorkshire Engine companies had traditional riveted construction tanks. Almost all of the 57xx class were equipped with vacuum train brake and steam train heating fittings (either from new or soon added), the exception being the 67xx series, 6700-6749 (later extended to 6779) which were 'shunting only' with locomotive steam and no train brake fittings.
Although small and compact the GWRs 57xx pannier tanks were powerful and versatile locomotives intended for much more than shunting work. The 4ft 7½in diameter wheels, as used on the 45xx 2-6-2 'small prairie' tanks, modernised boiler and chassis design allowed them to be driven at mainline stopping passenger train speeds. In the 1930s the new 57xx panniers quickly proved to be the ideal branch line workhorse and the class was expanded, eventually to 863 examples, becoming one of the backbones of GWR and BR Western region motive power into the 1960s. As dieselisation progressed the 30 year old 57xx type were naturally the first to be withdrawn, however London Transport was looking for locomotives to replace their aging ex-Metropolitan Railway engineering fleet. The 57xx pannier proved to be one of the few types suitable for the more restrictive Metropolitan line loading gauge. Despite the last 57xx being withdrawn from BR service in 1966 the LT locomotives served until 1971. 6 LT locomotives being bought for preservation along with 3 examples which had worked for the NCB and 7 rescued from scrap (numbers include 8750 sub-type)
Features of the Dapol O gauge 57XX & 8750 models
- Die cast Chassis and footplate for excellent adhesion and pulling power
- Powerful 5 pole motor providing fine power control
- Beautifully detailed body with correct body type variations applied where relevant with many separately added details
- Partial representation of working inside motion and many other exquisite fine details
- • Four cabs for original 57XX, Later 57XX, 8750 Collett cab and London Transport cab
- Sprung Buffers
- Removable roof, secured with magnets for ease of fitting engine crew
- Working cab doors, where fitted
- Flickering fire box glow
- Ash pan with correct double brake rodding
- Expertly applied livery
- Wheels conform to the new O Gauge standard, suitable for O Super Fine
- DCC Ready with a 21 pin decoder socket
- Sound fitted versions offered, Sound recorded from L92 (5786)