South Devon Railway 7ft broad gauge atmospheric railway baulk track 3m no ballast. The SDR ran as an atmospheric railway for just about a year from September 1847. The system was devised by Clegg and Samuda and adopted by Brunel as a major innovation. The tube in the centre of the track was exhausted of air by pumping stations positioned about every three miles along the route.
The 'locomotive' was a special carriage which had a piston in the pneumatic tube. The piston raised a longitudinal flap immediately behind the piston head and the inrushing air propelled the piston forward. Atmospheric trains regularly achieved 40mph and a top speed of 70mph-plus was recorded; an extraordinary achievement for 1847.
The line ran from Exeter to Newton Abbot and was due to be extended to Plymouth. However, the natural materials used quickly deteriorated and it became impossible to maintain the necessary vacuum/low pressure in the tube. If only Brunel had had plastics available! Thereafter, the scheme was abandoned and replaced by a conventional broad gauge railway.
However, the scenic route along the Exe estuary and sea wall at Dawlish remains as the main line to Penzance.
NB. Do not make junctions using this track. Turnouts did not have the vacuum tube. Use my ordinary broad gauge track for all pointwork and sidings.
Тип: track