Dick Allan’s
Crampton locomotives are among the most fascinating ever built.

Engines to the design of Thomas Russell Crampton were built from 1846 by various builders. In Great Britain the main ones were Tulk and Ley, and Robert Stephenson & Co.

Crampton’s unmistakeable engines were characterized by low-slung boilers and large driving wheels whose axle was placed behind the firebox. As a result, a low centre of gravity meant that they were stable at high speeds.

Another peculiarity on some Crampton locomotives was the use of a boiler of oval cross-section, to lower the centre of gravity. Today that would be regarded as bad practice because the internal pressure would tend to push the boiler into a circular cross-section with a risk of failure.

Some 51 Crampton locomotives were used on British railways and speeds of up to 120 km/h (75 mph) were achieved on the LNWR.  However, they were more popular in France, Germany and the United States. One of the French examples has been preserved in the French Railway Museum at Mulhouse in working order.

Most Cramptons had a 4-2-0 wheel layout, but some, including LNWR Liverpool, No 245, the loco modelled by Dick Allan, was 6-2-0 and fitted with an oval boiler.

It had works number 355 and was built by Bury, Curtis and Kennedy in 1848. Driving wheels were 8 feet (2.44 m) diameter, grate area 21.5 square feet (2.00 sq m), heating area 2,290 square feet (213 sq m), boiler pressure 120 lb/psi, cylinders 18"x24" (460mm x 610mm). It was awarded a Gold Medal at the Great Exhibition of 1851.

Dick’s locomotive is pictured here with some contemporaneous rolling stock: third and first class carriages, followed by a luggage and brake van..