Data from Record of Recent Construction #55 (Baldwin Locomotive Works, 1906), p. 30-31; and DeGolyer, Volume 29, p. 253 and Volume 49, p. 79.. Works numbers were 30039 in January 1907; 30067-30068 in February; 33512 in June 1909; and 33527-33528 in July.
This cabbage-stacker was one of the few Eight-wheeler designs on the metre gauge that ran as a two-cylinder compound. Baldwin's specs show rail weights of 40 lb/yard (20 kg/metre), maximum grades of 2% and curves of 17 degrees (328 foot/100 metres radii). In the specifications for the first three, a note warned"Special attention to be given to stay bolts as R R Co [sic] complains of those [unclear] on previous engines."
Connelly's record of Baldwin orders does not say if the class was converted to simple-expansion.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 61 |
| Locobase ID | 10989 |
| Railroad | American (Porto Rico) |
| Country | USA-Puerto Rico |
| Whyte | 4-4-0 |
| Number in Class | 6 |
| Road Numbers | 61-66 |
| Gauge | Metre |
| Number Built | 6 |
| Builder | Burnham, Williams & Co |
| Year | 1907 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 8.17 / 2.49 |
| Engine Wheelbase (ft / m) | 20.42 / 6.22 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.40 |
| Overall Wheelbase (engine & tender) (ft / m) | 38.25 / 11.66 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 37,380 / 16,955 |
| Engine Weight (lbs / kg) | 64,430 / 29,225 |
| Tender Loaded Weight (lbs / kg) | 45,570 / 20,670 |
| Total Engine and Tender Weight (lbs / kg) | 110,000 / 49,895 |
| Tender Water Capacity (gals / ML) | 2200 / 8.33 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 4 / 4 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 31 / 15.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 50 / 1270 |
| Boiler Pressure (psi / kPa) | 213 / 1470 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 13" x 18" / 330x457 (1) |
| Low Pressure Cylinders (dia x stroke) (in / mm) | 19" x 18" / 483x457 (1) |
| Tractive Effort (lbs / kg) | 7503 / 3403.31 |
| Booster (lbs) | 6 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.98 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 140 - 2" / 51 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 9.83 / 3 |
| Firebox Area (sq ft / m2) | 62 / 5.76 |
| Grate Area (sq ft / m2) | 9.90 / 0.92 |
| Evaporative Heating Surface (sq ft / m2) | 777 / 72.21 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 777 / 72.21 |
| Evaporative Heating Surface/Cylinder Volume | 560.37 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 2109 |
| Same as above plus superheater percentage | 2109 |
| Same as above but substitute firebox area for grate area | 13,206 |
| Power L1 | 6533 |
| Power MT | 770.61 |