Clear Lake Lumber Company 2-6-2 "Prairie" Locomotives in the USA

Class Details by Steve Llanso of Sweat House Media

Class 7 (Locobase 15214)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Vol 71, pp. 231+. See also the Clark Kinsey photograph and text at the University of Washington Libraries, Special Collections Division photographic archive entry at []. Works number was 57014 in September 1923.

Clear Lake Lumber Company of Skagit County, Washington State was established in 1913 when the earlier, identically named company (originally Bratnober-Waite Lumber Company) merged with Skagit Logging Company and Mt. Baker Timber Company. The associated railway would grow to 35 main line miles and 60 branch-line miles.

The caption also tells us that the CLLC's peak year of employment came in 1925 with 1,236 men, but that the company fell into receivership by the end of that year and was sold to a bank after a contentious auction in 1927 as "the largest sale of its kind ever held in northwest Washington." The bank sold the holdings to the newly formed Puget Sound Pulp & Timber Co in 1929.

The 7 was a typical small saddle-tank logging Prairie with the less common feature of superheating. The hotter steam required 9 1/2" (241 mm) piston valves.

After the CLLC closed, the 7 was bought by the Coos Bay Lumber Company. Operating as the 7 until World War II, the engine took a new number 19 when it entered the US Navy at Hunters Point in September 1942 and operated for the USN until October 1947, when it was scrapped.

The caption also answers a Locobase question about the name: "The name is reasonably descriptive, now that it is no longer used for extensive storage of saw logs. An early name was Mountain View."

Principal Dimensions by Steve Llanso of Middle Run Media

Locobase ID15214
RailroadClear Lake Lumber Company
Number in Class1
Road Numbers7
Number Built1
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m) 9.50 / 2.90
Engine Wheelbase (ft / m)25.33 / 7.72
Ratio of driving wheelbase to overall engine wheelbase 0.38
Overall Wheelbase (engine & tender) (ft / m)25.33 / 7.72
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)105,000 / 47,627
Engine Weight (lbs / kg)135,000 / 61,235
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)135,000
Tender Water Capacity (gals / ML)1800 / 6.82
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)600 / 2271
Minimum weight of rail (calculated) (lb/yd / kg/m)58 / 29
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)44 / 1118
Boiler Pressure (psi / kPa)165 / 11.40
High Pressure Cylinders (dia x stroke) (in / mm)17" x 24" / 432x610
Tractive Effort (lbs / kg)22,109 / 10028.49
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.75
Heating Ability
Tubes (number - dia) (in / mm)78 - 2" / 51
Flues (number - dia) (in / mm)13 - 5.375" / 137
Flue/Tube length (ft / m)12.42 / 3.79
Firebox Area (sq ft / m2)74 / 6.87
Grate Area (sq ft / m2)16.30 / 1.51
Evaporative Heating Surface (sq ft / m2)804 / 74.72
Superheating Surface (sq ft / m2)188 / 17.47
Combined Heating Surface (sq ft / m2)992 / 92.19
Evaporative Heating Surface/Cylinder Volume127.42
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation2690
Same as above plus superheater percentage3201
Same as above but substitute firebox area for grate area14,530
Power L15496
Power MT346.19

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Wes Barris