my ESPEE MODELERS ARCHIVE

California's Railroad to the U.S. 1861 - 1996

15 units built

SP all ready had a further 15 articulated compounds on order from Baldwin when the ideas and plans were drawn for the Cab Forward idea. The plans were sent to Baldwin and the order for #4002-4016 emerged from the erection shop in 1909/1910 as Cab Forwards.

One problem immediately arose with the new Cab Forward arrangement. The fuel oil had to travel all the way from what the front of the locomotive to the back, before being admitted to the firebox burner; and at times up hill when going up a grade. The final solution was too pressurize the tender with 5 pounds of air pressure. To achieve this the tenders were made air tight and braced with tie-rods and baffle plates. The fuel oil was also heated (I imagine), via steam coils in the base of the oil compartment.

The success in fuel savings and increased tonnage pulled over Donner Pass by the MC-2's caused SP to order more, and in 1911 Class MC-4 #4017-4028 were delivered.

To try to get more tractive effort out of these locos, tender booster engines were tried on a couple of engines but weren't successful so were removed.

Between 1927 and 1931 most MC-2's were converted to single expansion and classed AC-1.

References:

• A Century of SP Steam Locomotives - Guy L. Dunscomb
• SP Co. Steam Locomotive Compendium - Diebert & Strapac
• Cab-Forward - Robert J. Church
• Cab-In-Front (The Half Century Story of An Unconventional Locomotive) - John.B.Hungerford © 1959
  • reprinted by PFM 1974

Modeling choices at the moment are:

• For N Scale:
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• For HO Scale:
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• For S Scale:
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• For O Scale:
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