Data from "Railway Notes -- Rhymney Railway," The Locomotive Magazine, Volume XV [15] (14 February 1909), p. 22. See also "Rhymney Railway S Class" posted 11 November 2021 on Jim Champ's Introduction to Great Western Locomotive Development blog at [], last accessed 22 October 2025. (Thanks to Mr. A. McDiarmid HND BA Railway Mechanical Engineer for his 23 March 2023 email noting the proper nomenclature for RR locomotive classes.) Works numbers were 846-849.
Four dock traffic and shunting (switching) locomotives of standard size, although Jim Champ characterized the quartet as "powerful and heavy shunting engines."
They bore a definite family resemblance to the R class 0-6-2T [Locobase 10511]," wrote Champ, "with the same coupled wheelbase but a shorter boiler, a round topped firebox and smaller driving wheels. " By grouping, they had acquired A class boilers.
All were taken into the GWR as part of the Grouping amalgamation on 1 January 1922. GWR's shops retrofitted the Ss with a Standard 10 superheated tapered boilers in 1930 and larger bunkers. Renumbered in 1946, they continued to serve until 1953-1954.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | S |
| Locobase ID | 10686 |
| Railroad | Rhymney (GWR) |
| Country | Great Britain |
| Whyte | 0-6-0 |
| Number in Class | 4 |
| Road Numbers | 111-114/608-611/93-96 |
| Gauge | Std |
| Number Built | 4 |
| Builder | Hudswell, Clarke |
| Year | 1907 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 15.25 / 4.65 |
| Engine Wheelbase (ft / m) | 15.25 / 4.65 |
| Ratio of driving wheelbase to overall engine wheelbase | 1 |
| Overall Wheelbase (engine & tender) (ft / m) | 15.25 / 4.65 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 41,888 / 19,000 |
| Weight on Drivers (lbs / kg) | 123,872 / 56,187 |
| Engine Weight (lbs / kg) | 123,872 / 56,187 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | |
| Tender Water Capacity (gals / ML) | 1320 / 5 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 2.20 / 2 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 69 / 34.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 52.50 / 1334 |
| Boiler Pressure (psi / kPa) | 175 / 1210 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 18" x 26" / 457x660 |
| Tractive Effort (lbs / kg) | 23,868 / 10826.36 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 5.19 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 244 - 1.75" / 44 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 11.33 / 3.45 |
| Firebox Area (sq ft / m2) | 108.50 / 10.08 |
| Grate Area (sq ft / m2) | 18 / 1.67 |
| Evaporative Heating Surface (sq ft / m2) | 1377 / 127.93 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 1377 / 127.93 |
| Evaporative Heating Surface/Cylinder Volume | 179.82 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 3150 |
| Same as above plus superheater percentage | 3150 |
| Same as above but substitute firebox area for grate area | 18,988 |
| Power L1 | 3838 |
| Power MT | 204.92 |