ROGER KEEY writes from Christchurch about his latest
Model Building.
I enclose some photographs of two models of steam-traction vehicles that were used for heavy goods transport by road in the early part of the twentieth century. These vehicles were a development of earlier traction engines. Indeed, the "overtype" engines were little more than a traction engine fitted with a truck's decking. Both models are based on the "undertype" engines, in which the cylinders and crankshaft are placed below the chassis.
Photographs A and B show two views of the 1917 Yorkshire steam wagon. The Yorkshire company produced thousands of such wagons between 1913 and 1932. In this example, the driver sat perilously sandwiched between the horizontal boiler and the cylinder. The model has been made to the limitations of a 1960's red-green No 9 set. (This necessitated some imaginative use of parts, such as the simulation of a cylindrical section with 1" pulleys fitted with rubber tyres!).
Photographs C and D show a model at of a 1918 Atkinson logger. This had a loading capacity of six tons, but with improvements in boiler design a truck with a capacity of twelve tons was built in 1923, the largest wagon in Britain at the time. The wagons were used on logging sites and for heavy goods traffic in general. The logger was fitted with twin cylinders and a layshaft for the valve motion, which was driven from a spur gear on the crankshaft. Due to the limitations of Meccano the valve-reversing mechanism is not simulated. The rear axle is driven by chain from the crankshaft. (After I processed, the film I noted that the position of one stub axle and a front mudguard had been displaced!!).
Ed Not enough space for photo A which is a front view of the 1917 truck.
