San Diego & Southeastern 2-4-2 "Columbian" Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class 2 (Locobase 7273)

Data from the SD&A 5 - 1921 Locomotive Diagram book supplied in May 2005 by Allen Stanley from his extensive Raildata collection. 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.

Specifications by Steve Llanso of Sweat House Media
Locobase ID7273
RailroadSan Diego & Southeastern (SP)
Number in Class2
Road Numbers2, 5
Number Built2
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase (ft) 6.25
Engine Wheelbase (ft)22
Ratio of driving wheelbase to overall engine wheebase 0.28
Overall Wheelbase (engine & tender) (ft)22
Axle Loading (Maximum Weight per Axle) (lbs)
Weight on Drivers (lbs)59,900
Engine Weight (lbs)83,900
Tender Loaded Weight (lbs)
Total Engine and Tender Weight (lbs)83,900
Tender Water Capacity (gals)
Tender Fuel Capacity (oil/coal) (gals/tons)
Minimum weight of rail (calculated) (lb/yd)50
Geometry Relating to Tractive Effort
Driver Diameter (in)44
Boiler Pressure (psi)174
High Pressure Cylinders (dia x stroke) (in)14" x 20"
Tractive Effort (lbs)13,177
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.55
Heating Ability
Firebox Area (sq ft)55
Grate Area (sq ft)12.50
Evaporative Heating Surface (sq ft)700
Superheating Surface (sq ft)
Combined Heating Surface (sq ft)700
Evaporative Heating Surface/Cylinder Volume196.44
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation2175
Same as above plus superheater percentage2175
Same as above but substitute firebox area for grate area9570
Power L13491
Power MT256.97


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