The Corral Hollow Road was built in 1895-1896 as a coal road between Stockton, Calif, and Tesla. The 36-mile (58-km) road used 56 lb/yard (28 kg/metre) rail on "closely spaced" ties. It was expected to tap coal deposits in Corral Hollow Valley. Once the promise of coal-generated power was eclipsed by the abundant hydro-electric potential, the developers turned to promoting briquetting, says Patterson, which was the packaging of coal for home heating and cooling. "They were the first to promote this process in the United States and grew to become the largest mining operation in California."Tesla Mining was an active entrepreneurial business, developing both a brick and pottery business as well as the only factory making glass panes west of the Mississippi.
The Western Pacific bought the A&SJ in July 1903 and maintained the coal business through several fires in the Tesla Mine until a flood closed the mine in 1910. Ultimately, the WP incorporated the Stockton-Tracy segment into its mainline.
"TF" stands for Ten-wheeler freight and this pair obviously delivered useful power on light branch lines . 121 was scrapped in December 1934, but 122 last ran in December 1947.
The next year completed the class with 21 more engines. Road numbers 99-106 came first, costing $14,291 each and consisting of works# 46430-46437. Immediately following - at a higher price of $14,585 apiece - were works# 46438-46450.
Drury (1993) notes that the WP never had a great need for heavy passenger power. So these Ten-wheelers, although "not state-of-the-art passenger power," were adequate for the road until the 1930s. While the 30s saw most of the class heading to the scrapyard, some held on through World War II. 71, 76, 77, 78, 81, 83, 84, 86, 89, 99, & 106 were last used in the late 1940s, while 94 operated until April 1953.
|Specifications by Steve Llanso of Sweat House Media|
|Class||TF-17||TP-29||TP-29 - superheated|
|Railroad||Alameda & San Joaquin (WP)||Western Pacific (WP)||Western Pacific (WP)|
|Number in Class||2||36||36|
|Locomotive Length and Weight|
|Driver Wheelbase (ft)||13.17||13.50||13.50|
|Engine Wheelbase (ft)||21.17||24.33||24.33|
|Ratio of driving wheelbase to overall engine wheebase||0.62||0.55||0.55|
|Overall Wheelbase (engine & tender) (ft)||46.33||57.92||57.92|
|Axle Loading (Maximum Weight per Axle) (lbs)||45,000|
|Weight on Drivers (lbs)||82,500||135,000||135,000|
|Engine Weight (lbs)||114,500||181,000||181,000|
|Tender Loaded Weight (lbs)||76,000||127,460||132,000|
|Total Engine and Tender Weight (lbs)||190,500||308,460||313,000|
|Tender Water Capacity (gals)||4000||6000||7000|
|Tender Fuel Capacity (oil/coal) (gals/tons)||1584||3070||3019|
|Minimum weight of rail (calculated) (lb/yd)||46||75||75|
|Geometry Relating to Tractive Effort|
|Driver Diameter (in)||57||67||67|
|Boiler Pressure (psi)||150||200||200|
|High Pressure Cylinders (dia x stroke) (in)||18" x 24"||21" x 26"||21" x 26"|
|Tractive Effort (lbs)||17,394||29,093||29,093|
|Factor of Adhesion (Weight on Drivers/Tractive Effort)||4.74||4.64||4.64|
|Firebox Area (sq ft)||131||193||228|
|Grate Area (sq ft)||25.68||33.50||33.60|
|Evaporative Heating Surface (sq ft)||1659||2597||2245|
|Superheating Surface (sq ft)||568|
|Combined Heating Surface (sq ft)||1659||2597||2813|
|Evaporative Heating Surface/Cylinder Volume||234.70||249.16||215.39|
|Computations Relating to Power Output (More Information)|
|Robert LeMassena's Power Computation||3852||6700||6720|
|Same as above plus superheater percentage||3852||6700||8064|
|Same as above but substitute firebox area for grate area||19,650||38,600||54,720|