Data from H A Vallance The Great North of Scotland Railway (1968 reprint, p 155) and the [] website of the Great North of Scotland Railway Association (visited 8 Dec 2004). Vallance shows a total heating surface of 756 sq ft. The data in the specifications is from Richard Marsden's LNER Encyclopedia, [], last accessed 25 Sept 2006.
These little side tanks were intended for switching and helper service, but they worked well on the Aberdeen commuter runs despite the demands of a tight schedule. The 3 in 1885 were a bit larger and weighed one more ton, but were otherwise similar. In 1907 all 9 were rebuilt with 846-sq ft boilers pressed to 150 psi.
In LNER service the 1884 batch were J90, the 1885s J91. The last J90 was withdrawn in 1936, the last J91 2 years earlier.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | D, E/ J90, J91 |
| Locobase ID | 6418 |
| Railroad | Great North of Scotland |
| Country | Great Britain |
| Whyte | 0-6-0T |
| Number in Class | 9 |
| Road Numbers | |
| Gauge | Std |
| Number Built | 9 |
| Builder | |
| Year | 1884 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 13.67 / 4.17 |
| Engine Wheelbase (ft / m) | 13.67 / 4.17 |
| Ratio of driving wheelbase to overall engine wheelbase | 1 |
| Overall Wheelbase (engine & tender) (ft / m) | 13.67 / 4.17 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 35,280 / 16,003 |
| Weight on Drivers (lbs / kg) | 96,880 / 43,944 |
| Engine Weight (lbs / kg) | 96,880 / 43,944 |
| Tender Loaded Weight (lbs / kg) | / 34,546 |
| Total Engine and Tender Weight (lbs / kg) | / 78,490 |
| Tender Water Capacity (gals / ML) | 1080 / 4.09 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 1.70 / 2 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 54 / 27 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 54 / 1372 |
| Boiler Pressure (psi / kPa) | 150 / 1030 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 16" x 24" / 406x610 |
| Tractive Effort (lbs / kg) | 14,507 / 6580.27 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 6.68 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 158 - 1.75" / 44 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | |
| Firebox Area (sq ft / m2) | 71.80 / 6.67 |
| Grate Area (sq ft / m2) | 14.82 / 1.38 |
| Evaporative Heating Surface (sq ft / m2) | 846 / 78.62 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 846 / 78.62 |
| Evaporative Heating Surface/Cylinder Volume | 151.48 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 2223 |
| Same as above plus superheater percentage | 2223 |
| Same as above but substitute firebox area for grate area | 10,770 |
| Power L1 | 2913 |
| Power MT | 198.87 |