No. 176 Gearing up the ex LMS 4P Tanks, Hornby and Bachmann
I have been revisiting my stock of ex LMS 2-6-4 4P tank engines. In total the LMS constructed some 650 of these engines starting in 1927. Construction continued into British Railways days in the late 1940s. You might also include the British Railways Standard 2-6-4 tanks which were given smaller wheels and classified as 4MT rather than 4P. The LMS engines can be divided into three basic types corresponding to the Superintending Engineer at the time of construction.
Ex LMS 4P Tank Engines – Hornby Fowler 4P (front), Hornby Stanier 4P (middle) and Bachmann Fairburn (top)
The first engines were designed by Sir Henry Fowler and I would say are characterised by a parallel boiler and massive smoke box. Later engines received cabs with side windows but this variation was not produced by Hornby.
42334, Hornby Fowler 4P Tank R3404
The second batch of engines was built by Sir William Stanier and is characterised by his signature taper boiler. A small number were built with three smaller cylinders for use on the Tilbury and Southend Line. They also have smaller smoke boxes and no heavy motion bracket. Hornby did not produce a model of this variation.
42616, Hornby Stanier 4P Tank R2732
The final type built under the direction of Charles E Fairburn is characterised by a gap in the running plate in front of the cylinders similar to the style adopted for the later British Railways Standard classes.
42691, Bachman Fairburn Tank 32-878
The Fairburn engines have a shorter coupled wheel base and a reduced overall length. Bachmann produced a couple of models of the Fairburn tank in 2007 and these have been added to at regular intervals with different numbers and liveries.
All the LMS engines have 5’-9” driving wheels (compared to the 5’-8” wheels of the BR Standard 4MT). The picture above highlights the shorter overall length of the Fairburn engine. I think the picture also shows the heavier outline of the parallel boiler and firebox of the Fowler engines.
Ex LMS 4P Tank Engines – Hornby Fowler 4P (left), Hornby Stanier 4P (middle) and Bachmann Fairburn (right)
Another comparison image contrasting the heavy smoke door of the Fowler and highlighting the gap in the footplate in front of the cylinders on the Fairburn.
What about the models? If you pardon the pun, the Bachmann models are ‘built like a tank’. They weigh 385 gm compared to the 305 gm of the Hornby models. This might be one reason why the Bachmann versions are still popular with enthusiasts and have remained in production for over 17 years. In contrast I don’t think there have been many re-runs of the Hornby models and as a result good examples of both the Stanier and the Fowler engines are rare. I am well pleased with all three of my versions. The Hornby engines with their brass bearings are very quiet and smooth. My Bachmann models have tremendous haulage power. I do have one niggle with the Bachmann Fairburn. I don’t see how you can lubricate the axles without breaking at least one of the wire sand pipes off the chassis.
I didn’t buy a Stanier or a Fowler when new and have had to source models on the second hand market. Some time ago I bought a ‘new’ (unused) model from AC Spares. It came minus one sand pipe so perhaps a Hornby reject. More recently I have acquired a Stanier 4P. I don’t think that this had ever been taken out of its box. It still had the transport brackets through the tissue paper and polystyrene packing.
Sadly it couldn’t manage half a lap of my layout before it made a few loud clicks and stopped moving with the motor still running.
It doesn’t take much skill to deduce that the main drive gear might have cracked and slid along its axle. The repair is a little more difficult than the diagnosis. In the past I would have bought a new wheel set and the Hornby Service sheet has the part number. However given the age of the model it is perhaps not surprising that spare wheel sets are not available for the Stanier tank. This left me with two choices, repair the existing wheel set or replace with something similar.
As with the prototype 4P tank engines there are similarities between the different types and certainly some of Hornby’s spares are interchangeable between their Stanier and Fowler tank engines. In the case of the wheels I found a set for the Fowler Tank (X9180), same diameter, same gearing as the Stanier (X9767), but different shaped balance weights. I might be able to live with that.
With the comfort of knowing that I had some sort of replacement for the faulty wheel set I would attempt a repair. The drive gear is common to a lot of Hornby models and over time I have acquired a number of reject wheel sets. I would take some wheels apart and ‘borrow’ the gear which is a sliding fit. The Hornby 4P wheels were then gently pulled apart by hand, taking care not to twist the wheels on the axle. I only removed one wheel from the axle and I carefully noted how the wheels were quartered. The axle has splines to hold the gear wheel which is a sliding fit. Replacement is straightforward. Accurately refitting the driving wheel back on to the axle requires a degree of luck. The ends of the Hornby axle also has splines which hopefully should match grooves in the wheel that has just been removed. Remembering how the wheels were quartered helps when offering the wheel back up to the end of the axle and using only gentle pressure allows the wheel to find its original location on the splines. I must have got it right because the engine runs perfectly!
Either I am losing my touch or these plastic models are becoming more fragile with age. I must have leant too hard during the remediation of the Stanier and I snapped the black plastic motion bracket to valve gear. As with the wheels the correct spare part for the Stanier (X9765) does not appear to be available. Instead I sourced the equivalent parts for the Fowler which comes as part of the valve gear (X9178). I am guessing that the only difference between the sets of Hornby valve gear for the Stanier and Fowler engines is that the rods for the Stanier are fluted whilst for the Fowler they are modelled as being solid. The motion brackets appear to be identical.
On that happy note I will couple the engine back up and run a few trains:
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