The GWRs famed Chief Mechanical Engineer GJ Churchward had originally planned a light mixed traffic 4-6-0 in his range of standard types, but having seen the wide use of the 2-6-0 mogul in this role on US railroads altered his plans to produce the 43xx class. By the 1930s normal train speeds for secondary services were rising and the 43xx could give the crew a very rough ride. By the 1930s many of the 43xx class engines were found to need major repairs to or renewal of their Churchward design cylinder castings. CB Collett who had taken over as CME at Swindon after the grouping favoured the 2-axle leading bogie and began rebuilding 43xx 2-6-0 moguls as 4-6-0 locomotives of the 68xx Grange class. These engines were quite similar to his own Hall class design, but using the same 5'8" driving wheels of the 43xx with new design cylinders required a distinctive raised footplate section over the cylinder block.
The Grange class were well liked by crews, similar in power to the Hall but with slightly smaller wheels giving them the feel of extra pull with a free steaming boiler and a much better ride than the moguls they replaced! Their drawback was that the engines were now heavier and now barred from some routes worked with the 43xx moguls they were to replace.
The 78xx Manor class was designed along the same lines as the Grange, the chassis sharing the same range of standard components with the 68xx and 43xx classes but fitted with a smaller and lighter boiler to bring the engines' maximum axle load back into the GWRs 'blue' route limit of 17tons 12cwt (17.6tons).
The manor was not initially a great success, the smaller boiler not being able to keep up with the steam consumption of the cylinders, however with the country now at war these issues could not be addressed. It was only after nationalisation and recovery from wartime deferred maintenance that quite simple adjustments to the draughting, chimney and firegrate were found to greatly enhance the boilers' steam generating capabilities.
10 more engines were added to the class by British Railways in 1950, who gave the engines power classification 5MT, though 4MT might have been more appropriate. The Manors were withdrawn from service between 1963 and 1965, with 9 examples being preserved, with several being operational, proving themselves and ideal locomotive for longer heritage railways.
General Specification
Many original GA drawings were used in the development of these accurate and authentic model.
Building on the many developments from the Dapol Mogul including Dapol's award winning slide in PCB in the boiler for tool free DCC fitting and sugar cube speaker enclosure (for sound models). Conductive drawbar providing tender wheel pick-up and connections for high bass speaker.
The locomotive will have all of the usual refinements that are expected to be found on all Dapol models including:
• A diecast compensated chassis
• Detailed cab interior with screw reverse
• The front pony truck is also sprung and operates on a cam so the model will negotiate R2 curves with ease.
Technical Specification
• A slide in PCB offers simple ‘tool-free’ installation of a NEXT-18 DCC decoder and a ’no-solder’ speaker connection. This board slides through the smoke box door and connects directly to the locomotive mother board.
• The tender to locomotive drawbar includes reliable electrical connections moulded within the close-coupling push-fit coupling. This eliminates wired plugs and unreliable wiper style connections.
• The locomotive and tender have electrical pick-up on all driving and tender wheels
• An optional base reflex speaker can be fitted into the tender. An audio frequency filter is integrated within the main locomotive PCB to ensure each speaker reproduces within it’s ideal frequency range*
• Firebox glow (synchronised with sound*)
• Dapol’s proven slow speed mechanism and high torque motor