Toledo, Peoria, & Western 4-8-4 "Northern" Type Locomotives

Class H-10 (Locobase 283)

Don Ball called these the shyest Northerns he'd ever heard of. Certainly they were among the lightest of that wheel arrangement. They were obviously intended for freight work.

In February 2006, Locobase put out a call for more information on this design on the Classic Trains forum and received diagrams from Ray Breyer, a Peoria-based modeller who had obtained several pages of TP & W diagrams. From the diagram and the accompanying roster, Locobase was able to complete the record.

This design was remarkably small for a 4-8-4. Even the TP & W's own H-8/H-9 Consolidations (Locobase 7445) put more weight on the drivers. On the other hand, the firebox heating surface and superheat area were proportionally quite generous. Included in the direct heating surface were 15 sq ft of arch tubes and 89 sq ft of thermic syphons.

This class of six locomotives was produced in a batch by Alco in March 1937; works numbers were 68781-68786. At the other end of their TP & W careers, all six H-10s are shown as going to Keystone in 1950 in the following order:

83 2/25

82 5/25

81 7/25

85 9/5

86 9/12

80 10/11

Specifications
ClassH-10
Locobase ID283
RailroadToledo, Peoria, & Western
Whyte4-8-4
Road Numbers8080-8085
GaugeStd
BuilderAlco-Schenectady
Year1937
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase18.25'
Engine Wheelbase44.25'
Ratio of driving wheelbase to overall engine wheebase 0.41
Overall Wheelbase (engine & tender)89.25'
Axle Loading (Maximum Weight per Axle)51000 lbs
Weight on Drivers204000 lbs
Engine Weight361000 lbs
Tender Light Weight324000 lbs
Total Engine and Tender Weight685000 lbs
Tender Water Capacity18000 gals
Tender Fuel Capacity (oil/coal)18 tons
Minimum weight per yard of rail on which locomotive could run85 lb rail
Geometry Relating to Tractive Effort
Driver Diameter69"
Boiler Pressure250 psi
Cylinders (dia x stroke)23.5" x 30"
Tractive Effort51023 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.00
Heating Ability
Firebox Area443 sq. ft
Grate Area77.30 sq. ft
Evaporative Heating Surface2865
Superheating Surface1096
Combined Heating Surface3961
Evaporative Heating Surface/Cylinder Volume190.24
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation19325
Same as above plus superheater percentage24672.19
Same as above but substitute firebox area for grate area141394.28
Power L128528.02
Power MT1233.20

Credits

Introduction and specifications provided by Steve Llanso of Sweat House Media.