Steve Johnson Modelmaker
Bo-Bo Electric, 3rd Rail 750V dc
Built in 1899 by the LSWR at Nine Elms, its original purpose is undecided. It was built to tube gauge without buffers. It may have been intended to be used on the Waterloo & City line. However, it appeared at Wimbledon in 1915 usually shunting coal trucks at Durnsford Road Power Station, with buffers and drawgear. It survived into BR ownership being withdrawn in 1965.
Judith Edge makes a complete etched kit of this locomotive including motor and gearbox. I duly purchased one and have started to assemble it.
The body goes together very well and is fairly quickly assembled. A sub assembly carrying the motor, gearbox and driving wheels bolts underneath the body. Now, although the locomotive is a Bo-Bo, the model isn't, it is a 1-Bo-1. The centre two axles are rigid and driven by a Mashima 1020 motor via a High Level Kits Quadriver gearbox. The outer two axles are carried on other assemblies that pivot off the motor mount assembly. Dummy sideframes are attached, giving the impression of a Bo-Bo locomotive. Quite a clever work around and you wouldn't know unless you were told.
The above picture shows the assembled gearbox, with the moving extension allowing a compensated chassis.