Boston Locomotive Works 4-4-0 "American" Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class 15"" cylinders (Locobase 8811)

Data from Zerah Colburn, The Locomotive Engine (1851). Boiler pressure is an estimate.

Reorganization of Holmes Hinkley's firm (Hinkley & Drury) in 1848 led him to choose the name of the city within which the plant was located. A review of the Hinkley list compiled by William Edson and published in the Railroad & Locomotive Historical Society's Railway Bulletin 142 suggests that two of this design were supplied to the Odgensburg & Northern in New York State in September 1850 as works numbers 276-277. The engines bore the names La Grasse and Ausable.

In addition to boiler details, Colburn also gave the following data:

Water room (cu ft) 69.6

Steam room (cu ft) 41

Size of steam ports 10 1/16 x 1 5/16"

Size of exhaust ports 10 1/16 x 1 11/16".

Specifications by Steve Llanso of Sweat House Media
Class15"" cylinders
Locobase ID8811
RailroadBoston Locomotive Works
Number in Class
Road Numbers
Number Built
BuilderBoston Locomotive Works
Valve Gear
Locomotive Length and Weight
Driver Wheelbase
Engine Wheelbase
Ratio of driving wheelbase to overall engine wheebase
Overall Wheelbase (engine & tender)
Axle Loading (Maximum Weight per Axle)
Weight on Drivers
Engine Weight
Tender Light Weight
Total Engine and Tender Weight
Tender Water Capacity
Tender Fuel Capacity (oil/coal)
Minimum weight of rail (calculated)0
Geometry Relating to Tractive Effort
Driver Diameter60"
Boiler Pressure80 psi
Cylinders (dia x stroke)15" x 20"
Tractive Effort5100 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort)
Heating Ability
Firebox Area56.74 sq. ft
Grate Area 9.74 sq. ft
Evaporative Heating Surface767 sq. ft
Superheating Surface
Combined Heating Surface767 sq. ft
Evaporative Heating Surface/Cylinder Volume187.50
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation779
Same as above plus superheater percentage779
Same as above but substitute firebox area for grate area4539
Power L12055
Power MT

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