Normally resident at the end of the camping coach siding, this is the oldest coach on the railway which recalls a bygone era and reminds us of a great and controversial engineer.

11433 was constructed in Wolverton Works in 1915. It was not a passenger coach but  constructed for the transport of luxury cars to Scotland for the shooting season. The only passenger would presumably be the chauffeur who would ensure that his trusty steed did not come to any harm whilst in transit. The coach is fitted with large double doors at the end for loading and unloading the cars.

Whilst working on the coach some ten years ago we had to replace the wooden floor. Under the rotten planks was a beautifully crafted galvanised iron floor with integral drip trays to collect any oil from the underside of the vehicle.

The coach body is built of oak with a mixture of galvanised iron and timber panelling. Inside a mix of tongue and groove boarding and teak window frames show that even whilst the great war was on quality remained. The roof has a centre raised portion possibly to improve air circulation and help its load to dry a little in transit.

What is beneath the coach body is even more interesting. The pictures show that the coach has six wheels and leaf springs but all is not what it appears. Firstly the chassis is 25 years older than coach taking us back to the year 1890 when the LNWR was under the control of Chief Mechanical Engineer Francis William Webb.

Some Victorian Chief Engineers were authoritative; Webb was a total autocrat with a view that, at least in engineering matters, he was infallible.

His most famous obsession in locomotive design was compounding, a subject which still causes much debate. Another obsession was a deep-seated hatred of bogies on rolling stock, quite why is not now understandable. Possibly he thought that his track with its Webb patented 60ft rails did not require such things.

As a prolific inventor with more patents than any other CME, he not surprisingly patented his Webb Compensation System. In this the centre wheels are not fixed to the chassis but have a linkage arrangement between the top of the “W” iron and the bottom of the chassis, the wheel set being pulled into alignment using equalising bars visible on the coach sides. This is the later and somewhat simpler system.

The earlier system used separate sub-frames connecting with link pins and springs which, due to inadequate lubrication, caused horrific squealing and groaning noises on curves. Also, the drawings show that the pins would wear rapidly causing possible fracture or dislocation.

To try to improve matters, secondary springs were used to try and pull the wheels into better alignment. The problem grew worse with 8 wheelers with riding qualities that must have been interesting to say the least. Needless to say with Webb’s departure, Wolverton rapidly went into bogie manufacturing with progressive removal of 6-wheel stock, the bodies being used as sheds and the chassis recycled.

11433 eventually became a Pooley Weighing Machine van,  it then went into departmental use and was bought for preservation in 1980. It was taken by rail to Southport Steam Centre, then moved to Llangollen in 1986. It has changed hands several times and remains privately owned.

LMS VEHICLES