Data from the SD&A 5 - 1921 Locomotive Diagram book supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See Locobase 7271 for a summary of Richard V. Dodge's account of the construction of the SD & A.
The SD&SE was formed in 1912 by the merging of the San Diego & Cuyamaca Railway and the San Diego Southern Railway. The Cuyamaca road offered access east to El Cajon and beyond. Dodge notes that in November 1917, the directors of the San Diego & Arizona Railway voted to buy the SD & SE to reduce overhead expenses.
The little saddle tanks shown in this entry bear a family resemblance in size and power to the Porters that served the Brooklyn Bridge lines in the 1890s; see Locobase 5867.
Once adopted by the SD & A, they were soon deemed excess to requirements and sold in 1919.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 2 |
| Locobase ID | 7273 |
| Railroad | San Diego & Southeastern (SP) |
| Country | USA |
| Whyte | 2-4-2ST |
| Number in Class | 2 |
| Road Numbers | 2, 5 |
| Gauge | Std |
| Number Built | 2 |
| Builder | Porter |
| Year | 1911 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 6.25 / 1.90 |
| Engine Wheelbase (ft / m) | 22 / 6.71 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.28 |
| Overall Wheelbase (engine & tender) (ft / m) | 22 / 6.71 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 59,900 / 27,170 |
| Engine Weight (lbs / kg) | 83,900 / 38,056 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | |
| Tender Water Capacity (gals / ML) | |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 50 / 25 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 44 / 1118 |
| Boiler Pressure (psi / kPa) | 174 / 1200 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 14" x 20" / 356x508 |
| Tractive Effort (lbs / kg) | 13,177 / 5976.99 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.55 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 112 - 2" / 51 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 10.96 / 3.34 |
| Firebox Area (sq ft / m2) | 55 / 5.11 |
| Grate Area (sq ft / m2) | 12.50 / 1.16 |
| Evaporative Heating Surface (sq ft / m2) | 700 / 65.06 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 700 / 65.06 |
| Evaporative Heating Surface/Cylinder Volume | 196.63 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 2175 |
| Same as above plus superheater percentage | 2175 |
| Same as above but substitute firebox area for grate area | 9570 |
| Power L1 | 3495 |
| Power MT | 257.27 |