Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 31, p. 157. See also David F Myrick, New Mexico's Railroads ( : University of New Mexico Press, 1990, reprint of Colorado Railroad Museum edition, first published in 1970), p. 212. Works number was 32564 in January 1908.
About the only physical difference between this logging Consolidation and its mainline brethren was the short wheelbase, which follows a slightly shorter set of tubes. Otherwise, the 12 had good power and a relatively large boiler.
The ZM, chartered in August 1891, served the American Lumber Company in New Mexico, which logged the Zuni Mountain pine tree timber and transported the logs on 60-65 lb/yard (30-32.5 kg/metre) down to Grants, NM, where the Atlantic & Pacific took the load into Albuquerque.
The 12 was sold in 1917 to another New Mexico timber company, the McKinley Land & Lumber Company.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 12 |
| Locobase ID | 13249 |
| Railroad | Zuni Mountain |
| Country | USA |
| Whyte | 2-8-0 |
| Number in Class | 1 |
| Road Numbers | 12 |
| Gauge | Std |
| Number Built | 1 |
| Builder | Burnham, Williams & Co |
| Year | 1908 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 14.25 / 4.34 |
| Engine Wheelbase (ft / m) | 22.33 / 6.81 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.64 |
| Overall Wheelbase (engine & tender) (ft / m) | |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 150,000 / 68,039 |
| Engine Weight (lbs / kg) | 167,000 / 75,750 |
| Tender Loaded Weight (lbs / kg) | 60,000 / 27,216 |
| Total Engine and Tender Weight (lbs / kg) | 227,000 / 102,966 |
| Tender Water Capacity (gals / ML) | 3000 / 11.36 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 4.50 / 4 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 63 / 31.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 50 / 1270 |
| Boiler Pressure (psi / kPa) | 180 / 1240 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 21" x 26" / 533x660 |
| Tractive Effort (lbs / kg) | 35,086 / 15914.76 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.28 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 322 - 2.25" / 57 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 13.37 / 4.08 |
| Firebox Area (sq ft / m2) | 195 / 18.12 |
| Grate Area (sq ft / m2) | 32.60 / 3.03 |
| Evaporative Heating Surface (sq ft / m2) | 2719 / 252.60 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 2719 / 252.60 |
| Evaporative Heating Surface/Cylinder Volume | 260.94 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 5868 |
| Same as above plus superheater percentage | 5868 |
| Same as above but substitute firebox area for grate area | 35,100 |
| Power L1 | 5318 |
| Power MT | 312.64 |