Data from NdeM 1926ca Locomotive Diagrams supplied in December 2010 by Allen Stanley.
This pair of narrow-gauge Consolidations first entered service on the Mexicano del Sur in June 1906 and March 1909 (Locobase 11749). They were among the last few engines built to specs that had been established in 1892, but with a higher boiler pressure.
Sometime after their arrival and likely after the NdeM absorbed the MdeSur in 1910, the railway's shops installed new boilers. In place of the 128 2 1/4" tubes of the earlier design, the vessels now held 27 more 2" (50.8 mm) tubes, which increased their heating surface area by 111 sq ft (14.5 sq m). The results preserved an acceptable factor of adhesion.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | G-030/G-021 |
| Locobase ID | 11907 |
| Railroad | Nacional de Mexico (NdeM) |
| Country | |
| Whyte | 2-8-0 |
| Number in Class | 2 |
| Road Numbers | 276, 282/120-121 |
| Gauge | 3' |
| Number Built | |
| Builder | NdeM |
| Year | 1905 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 10.83 / 3.30 |
| Engine Wheelbase (ft / m) | 16.83 / 5.13 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.64 |
| Overall Wheelbase (engine & tender) (ft / m) | 45.58 / 13.89 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 80,135 / 36,349 |
| Engine Weight (lbs / kg) | 88,000 / 39,916 |
| Tender Loaded Weight (lbs / kg) | 60,000 / 27,216 |
| Total Engine and Tender Weight (lbs / kg) | 148,000 / 67,132 |
| Tender Water Capacity (gals / ML) | 3000 / 11.36 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 2041 / 7725 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 33 / 16.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 37 / 940 |
| Boiler Pressure (psi / kPa) | 145 / 1000 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 17" x 20" / 432x508 |
| Tractive Effort (lbs / kg) | 19,254 / 8733.48 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.16 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 155 - 2" / 51 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 14.50 / 4.42 |
| Firebox Area (sq ft / m2) | 72.40 / 6.73 |
| Grate Area (sq ft / m2) | 16.72 / 1.55 |
| Evaporative Heating Surface (sq ft / m2) | 1249 / 116.08 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 1249 / 116.08 |
| Evaporative Heating Surface/Cylinder Volume | 237.90 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 2424 |
| Same as above plus superheater percentage | 2424 |
| Same as above but substitute firebox area for grate area | 10,498 |
| Power L1 | 2744 |
| Power MT | 301.96 |