| Power Classification | 7F |
| Introduced | 1914 and 1925 |
| Designer | Fowler |
| Company | SDJR |
| Weight – Loco | 68t 11cwt (Later batch 64t 15cwt) |
| Tender | 42t 13cwt |
| Driving Wheels | 4ft 8½ins |
| Boiler Pressure | 190psi superheated |
| Cylinders | Outside – 21in x 28in |
| Tractive Effort | 35,295lbf |
| Valve Gear | Walschaert (piston valves) |
The MR never owned anything larger than 0-6-0 engines throughout its existence (apart from the single 0-10-0 Lickey Banker). This class was unusual in that it was the only class of large engines that the Midland Railway (MR) had built, even though they were not built for themselves.
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Midland Railway standard 0-6-0 4F 43835 class introduced in 1911.In 1922 Armstrong Whitworth built five engines (44557-44561) for the SDJR to a slightly modified design. |
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7F built for SDJR in 1914 |
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Midland Compound introduced in 1905 was used for the boiler design for the 7F for the SDJR. |
In 1876 the Midland Railway (MR) and the London & South Western Railway combined forces to rescue the financially ailing Somerset & Dorset Railway. Under the arrangements to operate the line the MR took on the responsibility for the locomotives and the rolling stock.
The Somerset & Dorset Joint Railway (SDJR) acquired stock of standard MR type engines, but it was realised that something more powerful was needed to work the steeply graded Bath-Bournemouth line. The MR never owned anything larger than 0-6-0 engines throughout its existence (apart from the single 0-10-0 Lickey Banker).
Two plans for 0-8-0s were suggested in 1907 but would have been too heavy but it was evident that a special exception to the Midland Railway small engine policy was required. Fowler gave James Clayton, the draughtsman at Derby, a free hand to design the engine, and he produced something unlike any other Derby-designed locomotive of the time. The first six of this class of engines were built at Derby in 1914.
They were fitted with 4′ 9ʺ diameter Belpaire boilers and they were numbered 80-85. The engines were very distinctive in having a straight footplate which was raised with square corners over the cylinders which were set at a slight angle to the horizontal.
As the locomotives were initially too large for some of the turntables, it was envisaged that they would spend half their time travelling in reverse. Consequently, they were fitted with tablet exchanging apparatus on both sides of the locomotive. In addition, the first six were equipped with cab tenders, but these were later removed circa 1920.
In 1925 a further five engines (numbered 86-90) were built by Robert Stephenson and Company at Darlington and they were fitted with larger (5′ 3ʺ) diameter boilers and left hand drive. They were later all fitted with smaller diameter boilers although 53806-53808 retained their larger boilers until 1953-1955.
The engines were at first numbered 9670-9680 when they came into LMS stock in 1930, but they were renumbered 13800-13810 in 1932. Under BR ownership they became 53800-53810.
They spent the whole of their lives working freight traffic over the SDJR line. For a few months in 1918 number 85 was lent to the Midland Railway and it was tested on coal trains between Wellingborough and Brent. This was with a view to the Midland building some of these engines for themselves, but nothing ever came of it. This was perhaps due to the fact that despite being designed for climbing hills but they consumed considerable amounts of high quality coal and were hence not fuel efficient.
Withdrawals of the locomotives built in 1914 occurred between 1959 and 1962 and the five built in 1925 were all withdrawn between 1963 and 1964.
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Built |
Withdrawals | No. in Service | ||
| BR Numbers | Quantity | |||
| 1914 | 53800 – 53805 |
6 |
6 |
|
| 1925 | 53806 – 53810 |
5 |
11 |
|
| 1926-58 |
11 |
|||
| 1959 | 53800 | 1 |
10 |
|
| 1960 | 53802 | 1 |
9 |
|
| 1961 | 53801 & 53805 | 2 |
7 |
|
| 1962 | 53803 & 53804 | 2 |
5 |
|
| 1963 | 53810 | 1 |
4 |
|
| 1964 | 53806 – 53809 | 4 |
0 |
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Accident and Incidents
Combe Down tunnel had no intermediate ventilation and there were significant problems with fumes. On 20 November 1929, the driver and fireman of a northbound goods train were overcome by smoke. The train was moving very slowly in the tunnel due to a heavy load and due to starting from a standstill at Midford. The locomotive, S&DJR 2-8-0 89, plodded on and eventually breasted the summit of the gradient. Its downward course to Bath was accomplished more quickly, and the train ran away, crashing into the goods yard on the approach to Bath Green Park railway station, killing the driver, Henry Jennings, and two railway employees in the yard.
The fumes that overcame the footplate crew were a consequence of the restricted bore, lack of ventilation shafts, the exceptional humidity and lack of breeze, and the very slow speed of the train, running tender first. The inspecting officer, Colonel A. C. Trench recommended that maximum loads should be reduced or assistant engines provided to prevent a recurrence.
Preserved British Steam Locomotives 