Probably the oldest original fitting within the Roundhouse, our Sheerlegs provided a vital function when repairing and servicing locomotives. Current legislation means they can never be used again but we have plans to recreate all of the missing components to give an idea of the original appearance.
Sheerlegs are in use all over the world and are capable of lifting tremendous weights. The most notable applications are where they are mounted on barges and are capable of lifting sunken ships. These tend to be of a hinged ‘A’ frame construction with steel ropes to both lift the legs to the required position and to raise the load, offering a vertical lift with some degree of movement forwards and backwards by adjusting the angle of the legs. Further movement of the load can then be achieved by the movement of the barge.
Our Sheerlegs are fixed in position, are based on a tripod, are self-supporting, and are capable of a vertical lift only. However, they provided a vital function in a workshop where electric winches and hydraulic jacks were a thing of the future. The only source of power readily available was the muscles of the engineers and a simple application of physics which were utilized to create the mechanical advantage necessary to lift weights in excess of 40 tons.
Changing wheels on a locomotive is not as easy as on a car. Each pair of wheels are solidly connected together by a fixed axle and the only way to remove them for repair is to either lift the engine off them or to drop the wheels from beneath the engine into a pit. The favoured way was the former due to the cost and complexity of structure of the pit method (this may be seen at the NRM workshops). The whole front or rear end of the locomotive needed to be lifted to allow the wheels to be rolled out from underneath. In some locomotives this involved lifting a weight of over 48 tons. This could be achieved by four men, two men to each of the two winding levers.
The mechanical advantage needed was achieved by two linked means, a set of reducing gears and a compound pulley system.
Unfortunately the winding mechanism at the bottom of our Sheerlegs was scrapped by British Rail after 95 years use, well before the Roundhouse was saved. At the very top of the Sheerlegs can be seen one of the original pulleys with three wheels however. The lower pulley would have had two wheels.
Of course the sheerlegs had other uses. At 17 feet tall with the top above the level of the old gas lamps and with the building filled with the ever present haze from smoke and steam, it became an ideal place for young engine cleaners to hide from the shed foreman when work was all but finished. They were often found sitting on the high platform swinging their legs and dropping 'carbide bombs' onto the floor below.
Early views of Barrow Hill Roundhouse showing the Sheerlegs. These picture also give a good idea of the state of the roundhouse during restoration
In spite of extensive research we have been unable to locate pictures of our Sheerlegs lifting a locomotive but the pictures below show a similar mechanism in use.
The locomotive positioned under our Sheerlegs in the photograph above is a Thompson designed B1 that had been given the shed number 32 and was being used for carriage warming in the last years of its life. This was the last locomotive fired by Dave Darwin who has contributed articles throughout this website.
Introduced in 1942, there were 410 B1 locomotives built but only two made it into preservation, 61264 at North Yorkshore Moors Railway and 61306 (Mayflower) at the North Norfolk Railway.
61041, 61162, 61312 and 61315 were all based at Staveley GC sheds. The original number of the locomotive shown is 61315, Based at Staveley and Mexborough 1962/63, taken into departmental stock in 1966 and finally scrapped in 1968.