'Jubilee' Class No 1903 "Iron Duke"
This class of 40 locos was Mr. Webb's first design of 4-4-0 express engine and what handsome machines they were - to my mind the epitome of Victorian elegance. Two of the class were constructed in 1897, one being a 4-cylinder simple, the other a 4-cylinder compound. In 1899 and 1900 a further 38 compounds were built and the simple was converted to a compound. No 1903 was the first of the 1899 batch.
The model is constructed from the London Road Models kit straight as it came out of the box. It was the first of the production run to be sold and was a joy to build. All the parts fitted, it was accurate to the prototype and extra pieces were provided for those bits that inevitably fall onto the floor and disappear into a parallel universe only to reappear six months later. The designer of the kit, Jol Wilkinson, has done an excellent job. The only items I do not like are the handrail supports, which are nothing like those on the prototype.
The bogie in particular is an unusual and very effective design. A rubbing plate under the chassis rests on a similar plate on top of the bogie and the bogie axles are provided with independent springing at each end. The weight of the loco is thus supported by the bogie and the rear wheels. In my loco I have filled the boiler with ballast but have made sure that the centre of gravity is behind the front axle. I have then provided springing to the front axle in my usual way. Spring pressure on the front driving axle will transfer weight from the bogie onto the front axle until eventually the bogie would lift from the track and this pressure can easily be adjusted to achieve the optimum balance between traction and road holding.
An LH21 motor drives the rear axle via an underhung gearbox. Electrical pickup is taken from six wheels.
The loco weighs 275grms and exerts a pull of 35grms. The low power to weight ratio indicates that I could considerably increase the spring pressure on the front driving axle and thus improve the pulling power but, as it happily pulls my heaviest express at high speed, I am not going to bother!
Handsome machines, aren't they?
Right-hand side view
The bogie on the 'Jubilee' showing the excellent springing arrangement
View showing the springs on the front driving axle