Data from "Barry Railway," Locomotive Magazine, Volume XXIX [29] (15 June 1923), p. 171. See also H L Hopwood, "The Barry Railway: Its Characteristics, Engines and Traffic", Railway Magazine, Volume 42 (1918), pp. 215-227. Welsh Railways Research Circle, "Barry Railway (and related lines)" at [], last accessed 22 November 2021. Works numbers were 16466-16467 in 1905.
Joining the short-lived fad for rail motors, the Barry bought two rail motors for short-haul passenger service in the Vale of Glamorgan. Like most other such vehicles, the power unit drove the front bogie of a coach body whose total length over buffers reached 64 ft 10 in (19.76 m).
Its steam came from a vertical boiler that stood 9 ft (2.74 m) high in the carriage's head end. Over a round firebox rose a blossoming tube-bundle inside an inversely tapered boiler. Piston valves fed the cylinders immediately below the boiler.
According to the WRRC summary, service from Cardiff to Pontypridd began on 1 May 1905 and ended exactly one month later. RM's 1923 account states that the rail motors failed to develop the traffic adequately. Accordingly, the report concluded, "after a time service was reduced and in 1913 withdrawn altogether."
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | RM 1 |
| Locobase ID | 20959 |
| Railroad | Barry |
| Country | Great Britain |
| Whyte | 0-4-0+4T |
| Number in Class | 2 |
| Road Numbers | RM 1-RM 2 |
| Gauge | Std |
| Number Built | 2 |
| Builder | North British |
| Year | 1905 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 8 / 2.44 |
| Engine Wheelbase (ft / m) | 8 / 2.44 |
| Ratio of driving wheelbase to overall engine wheelbase | 1 |
| Overall Wheelbase (engine & tender) (ft / m) | 40 / 12.19 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | / 16,295 |
| Weight on Drivers (lbs / kg) | / 16,295 |
| Engine Weight (lbs / kg) | / 28,945 |
| Tender Loaded Weight (lbs / kg) | / 23,039 |
| Total Engine and Tender Weight (lbs / kg) | / 51,984 |
| Tender Water Capacity (gals / ML) | 600 / 2.27 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 0.83 / 0.80 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 43.50 / 1105 |
| Boiler Pressure (psi / kPa) | 160 / 1100 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 12" x 16" / 305x406 |
| Tractive Effort (lbs / kg) | 7203 / 3267.23 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 462 - 1.125" / 29 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 4.04 / 1.23 |
| Firebox Area (sq ft / m2) | 45 / 4.18 |
| Grate Area (sq ft / m2) | 11.50 / 1.07 |
| Evaporative Heating Surface (sq ft / m2) | 597 / 55.46 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 597 / 55.46 |
| Evaporative Heating Surface/Cylinder Volume | 285.05 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 1840 |
| Same as above plus superheater percentage | 1840 |
| Same as above but substitute firebox area for grate area | 7200 |
| Power L1 | 4553 |
| Power MT | |