'SMALL JUMBO' or 'WHITWORTH' Class, No 628 "TARTARUS"
This model was constructed from the London Road Models etched kit. This was originally part of the 'Connoisseur's Choice' range designed by the late lamented George Norton. I have built several of the kits from this range and have always found them to be accurate to the prototype and user-friendly to build, which is more than you can say about some others I have struggled with!
It is powered by my usual LH21 motor driving the rear wheels via an under-hung worm and wheel gearbox. The front wheels rock about a centre support, the front drivers are sprung and electrical pickup is taken from all six wheels. It runs smoothly and pulls well due to having lead in every possible space. Unfortunately I used Liquid Lead mixed with PVA glue for the ballast and this is causing the boiler to burst apart. I have not yet found a satisfactory way of removing the ballast and any suggestions are welcome.
The loco weighs 180grms and exerts a pull of 25grms. That is not a very good power to weight ratio and indicates that I could fit stronger springing to the front driving wheels and thus take some weight off the leading wheels where it is not assisting traction.
Side view of the 'Small Jumbo'
The works of the 'Small Jumbo'
The rods visible inside the frames, between the leading and centre axles, are imitation valve gear