Butte, Anaconda & Pacific 4-6-0 "Ten-Wheeler" Locomotives in the USA

Class Details by Steve Llanso of Sweat House Media

Class 20 (Locobase 10770)

Data from Baldwin Locomotive Works, Record of Recent Construction ((1903), No. 31, p. 15. See also DeGolyer, Volume 24, p. 37; and "No. 54 Formal --Thomas O Miles vs. Butte, Anaconda & Pacific Railway Co." , First Annual Report of the Board of Railroad Commissioners of the State of Montana, Volume 1 (1907-1908) (Helena, Mont: State Publishing Company, 1908), p. 35. Works number was 19389 in August 1901.

This passenger Ten-wheeler was one of only three BA&P locomotives that rolled on drivers taller than 57". It hauled passenger trains over the 26 miles (42 km) between Anaconda & Butte, a route that included Miles Crossing, Mont. The citizens in and around that town submitted a plea to the Montana Board of Railroad Commissioners to mandate a flag stop on an additional eastbound train. The BA&P agreed in May 1908 to add the stop to the No. 6 train.

See Locobase 8833 for a brief description of the BA&P. As noted there, the BA&P electrified in 1915. At that time, 20 was sold to Cuba's Central Toluca Chucho.

Principal Dimensions by Steve Llanso of Sweat House Media
Locobase ID10,770
RailroadButte, Anaconda & Pacific
Number in Class1
Road Numbers20
Number Built1
BuilderBurnham, Williams & Co
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)13.67 / 4.17
Engine Wheelbase (ft / m)25.25 / 7.70
Ratio of driving wheelbase to overall engine wheebase 0.54
Overall Wheelbase (engine & tender) (ft / m)54.25 / 16.54
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)118,425 / 53,717
Engine Weight (lbs / kg)152,180 / 69,028
Tender Loaded Weight (lbs / kg)100,000 / 45,359
Total Engine and Tender Weight (lbs / kg)252,180 / 114,387
Tender Water Capacity (gals / ML)5000 / 18.94
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)10 / 9.10
Minimum weight of rail (calculated) (lb/yd / kg/m)66 / 33
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)67 / 1702
Boiler Pressure (psi / kPa)200 / 13.80
High Pressure Cylinders (dia x stroke) (in / mm)19" x 26" / 483x660
Tractive Effort (lbs / kg)23,815 / 10802.32
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.97
Heating Ability
Firebox Area (sq ft / m2)174.50 / 16.22
Grate Area (sq ft / m2)34 / 3.16
Evaporative Heating Surface (sq ft / m2)2420 / 224.91
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)2420 / 224.91
Evaporative Heating Surface/Cylinder Volume283.63
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation6800
Same as above plus superheater percentage6800
Same as above but substitute firebox area for grate area34,900
Power L18618
Power MT481.30

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