In 1937, StL-SW's Pine Bluff, AR shops built five (road numbers 810 through 814) additional Class L-1s which were identical to the 10 from Baldwin. Then, in 1943, another five (road numbers 815 through 819) came out of the Pine Bluff shops which were very similar to the other Class L-1s except they weighed about 6,000 pounds more.
There is one surviving Class L-1, number 819, at the Arkansas Railroad Museum in Pine Bluff, AR.
|Class||Road Number||Year Built||Builder|
The firebox heating surface includes 107 sq ft (9.9 sq m) of thermic syphons (two in the firebox, one in the combustion chamber) and 104 sq ft (9.65 sq m) in the combustion chamber. Piston valves measured 14"(356 mm) in diameter. A Worthington Type S, No. 5, feed water heater had a rated maximum capacity of 75,000 lb (34,019 kg) or about 9,000 US gallons (34,065 litres) per hour.
The StL-SW diagram shows that of the driving wheelbase, only 12 feet 2 inches (3.7 m) was considered "rigid", meaning the lead driving axle had considerable lateral play. The frame and cylinders were combined in a integral steel casting. 800-804 truck bearings were Timken rollers while 805-809 ran SKFs. Later, all 10 were refitted with Boxpok drivers and Timken roller bearings on all driving journals.
The first 10 were built by Baldwin in 1930 and increased freight power by 30% while moving it faster. The specification noted that the maximum grade of 1.2% ran for 7,000 feet (2,134 m) and that the locomotive was "to handle maximum tonnage based on cylinder capacity and adhesive ratio with continuous pull of four miles [6.4 km] over continuous 1% grade at fifteen miles per hour minimum speed in addition to handling same load over above specified ruling grade [i.e. 1.2%] at same speed."
Pine Bluff, the Cotton Belt's main shop location, built its own variant; see Locobase 8479.
The first ten Northerns on the StL-SW came from Baldwin in 1930 and they're described in Locobase 245. In this entry, we show the second ten, which were produced by Pine Bluff, the Cotton Belt's main shop location, beginning in 1937. These had roller bearings on all axles and Boxpok drivers. Also, the superheater lost 98 sq ft (9.1 sq m) of heating surface, probably by eliminating elements from a few 3 1/2" flues, as the tube and flue counts remained the same at 52 and 200, respectively.
The Baldwin engines were modified to a similar standard and Pine Bluff supplied another five engines to support wartime traffic in 1942.
|Specifications by Steve Llanso of Sweat House Media|
|Class||L1 - 800||L1 - 810|
|Railroad||Cotton Belt (StLSW)||Cotton Belt (StLSW)|
|Number in Class||10||10|
|Locomotive Length and Weight|
|Driver Wheelbase (ft)||18.75||18.75|
|Engine Wheelbase (ft)||45||45|
|Ratio of driving wheelbase to overall engine wheebase||0.42||0.42|
|Overall Wheelbase (engine & tender) (ft)||87.58|
|Axle Loading (Maximum Weight per Axle) (lbs)||61,500||62,000|
|Weight on Drivers (lbs)||242,500||248,000|
|Engine Weight (lbs)||422,500||425,500|
|Tender Loaded Weight (lbs)||307,000||312,000|
|Total Engine and Tender Weight (lbs)||729,500||737,500|
|Tender Water Capacity (gals)||15,000||15,000|
|Tender Fuel Capacity (oil/coal) (gals/tons)||5000||5000|
|Minimum weight of rail (calculated) (lb/yd)||101||103|
|Geometry Relating to Tractive Effort|
|Driver Diameter (in)||70||70|
|Boiler Pressure (psi)||250||250|
|High Pressure Cylinders (dia x stroke) (in)||26" x 30"||26" x 30"|
|Tractive Effort (lbs)||61,564||61,564|
|Factor of Adhesion (Weight on Drivers/Tractive Effort)||3.94||4.03|
|Firebox Area (sq ft)||469||469|
|Grate Area (sq ft)||88.30||88.30|
|Evaporative Heating Surface (sq ft)||4728||4728|
|Superheating Surface (sq ft)||2060||1962|
|Combined Heating Surface (sq ft)||6788||6690|
|Evaporative Heating Surface/Cylinder Volume||256.47||256.47|
|Computations Relating to Power Output (More Information)|
|Robert LeMassena's Power Computation||22,075||22,075|
|Same as above plus superheater percentage||28,698||28,477|
|Same as above but substitute firebox area for grate area||152,425||151,253|