Data from "Steam Rail Motor-Car", Engineering, Volume XVII (1 November 1907), p. 600. Works numbers were 805-806.
The Rhymney had Hudswell, Clarke build a pair of rail motors. Unlike many rail motors, Rhymney's #1 was a full-fledged prime mover semi-permanently linked to a 64-passenger coach. C T Hurry Riches designed the combination and contracted with Messrs Cravens Ltd of Sheffield to build the coach. All seating was designed for third class and was divided between smoking and non-smoking sections.
The locomotive was rated to pull a six-wheel coach up a 1 in 35 (2.86%) grade. When they entered service in October, the Rhymney's general manager E A Prosser put one of the cars in service between Caerphilly and Senghenydd on a five-trains-a-weekday schedule.
In 1911, the 1 was converted to an independent, mixed-traffic tank locomotive that operated "chiefly between Rhymney Bridge, Ystrad Mynach, and Merthyr with four six-wheel coaches." At that time, the #2 still ran on the Senghenydd branch.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | Steam Rail Motor-Car |
| Locobase ID | 20034 |
| Railroad | Rhymney |
| Country | Great Britain |
| Whyte | 0-4-0T+4 |
| Number in Class | 2 |
| Road Numbers | 1 |
| Gauge | Std |
| Number Built | 2 |
| Builder | Hudswell, Clarke |
| Year | 1907 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 8.50 / 2.59 |
| Engine Wheelbase (ft / m) | 8.50 / 2.59 |
| Ratio of driving wheelbase to overall engine wheelbase | 1 |
| Overall Wheelbase (engine & tender) (ft / m) | 55.83 / 17.02 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | |
| Engine Weight (lbs / kg) | |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | |
| Tender Water Capacity (gals / ML) | 840 / 3.18 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 42 / 1067 |
| Boiler Pressure (psi / kPa) | 175 / 1210 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 12" x 16" / 305x406 |
| Tractive Effort (lbs / kg) | 8160 / 3701.32 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 210 - 1.75" / 44 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 6.08 / 1.85 |
| Firebox Area (sq ft / m2) | 71.70 / 6.66 |
| Grate Area (sq ft / m2) | 14.51 / 1.35 |
| Evaporative Heating Surface (sq ft / m2) | 661 / 61.41 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 661 / 61.41 |
| Evaporative Heating Surface/Cylinder Volume | 315.60 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 2539 |
| Same as above plus superheater percentage | 2539 |
| Same as above but substitute firebox area for grate area | 12,548 |
| Power L1 | 5963 |
| Power MT | |