Several years ago members of the Twickenham & District MRC decided their next O gauge layout would be a model of Kensington Addison Road c1925, the station nowadays known as Kensington Olympia. Considerable research followed and the working timetables showed that a large proportion of the passenger services were operated by L&NWR electric trains running between Earl's Court and Willesden. This route was the first part of the L&NWR inner suburban network to be electrified, using 3rd and 4th rail DC, in 1914.
The L&NWR placed orders for three-car electric multiple units from Metropolitan-Cammell in Birmingham. These units were formed Driving Motor Brake Third (DMBT) + Trailer Composite (TC) + Driving Trailer Third (DTT). All the cars were open saloons and the electrical equipment was in a compartment behind the driving cab in the DMBT. The units were delivered in three batches. The first batch, introduced in 1914, was fitted with electrical equipment from Siemens of Germany. Due to the War, the following two batches, introduced in 1915 and 1921, used equipment from Oerlikon of Switzerland.
Back at the club, everyone agreed that 3rd and 4th rail electrification would be an unusual feature for the layout and for some reason I volunteered to build a 7mm scale electric set.