Railroad technology changed dramatically in the early 20th century. Freight cars were getting larger and trains were getting longer. As a result, more efficient steam locomotives were needed. Designers needed a way to evaluate their new, improved locomotives and dynamometer cars became their rolling laboratories.
These cars carried a large dynamometer (a device for measuring mechanical force) and recording equipment to gather information on fuel and water consumption, drawbar pull, train weight, boiler pressure and more. The cars also provided quarters for testing crew. Coupled directly behind the loco, dynamometer cars could be seen trailing light engine test runs or with freight or passenger trains trailing them.
While dynamometer cars first appeared in the late 1800s, cars similar to the new Walthers Dynamometer Car hit the rails during the 1920s. Early on, they were used to test steam locomotive performance. As the railroads dieselized, the cars were modified to test diesel locomotive performance. These cars typically had long lives, many lasted well into the 1980s and several are preserved in museums.
The Walthers Dynamometer Car works like the prototype; couple it between the locomotive and train and it measures drawbar pull. The data readout on the car displays how much each engine or consist is pulling. By taking multiple readings on curves, where freight cars will have more drag from wheel friction, and on grades, where trains work against gravity, modelers can make comparisons among their locomotives.
Because it actually tests the pulling power of HO locomotives, this working model is a must for any steam- or diesel-era model railroad. Armed with the information they gather from the tests, modelers can tailor locomotive assignments to fit specific sections of their layout.
Modelers can run the Dynamometer Car as a realistic piece of work equipment. In operation, just couple it between the locomotives and train. As a scenic addition, it can be placed at a servicing facility, in a shop scene or on a siding at a depot.
Detailing on the Dynamometer Car includes separate ladder, underbody and roof details; starter points for wire grab irons (sold separately); realistic paint schemes; appropriate free-rolling trucks; and working knuckle couplers.
Ready-to-run Dynamometer Cars feature working testing equipment with a data readout on the car. These working models sell for $32.98 each and are available in the following roadnames:
932-4651 Nickel Plate Road
932-4652 CB&Q
932-4653 C&O
932-4654 NYC
932-4655 PRR
932-4656 MILW
932-4657 Kansas City Southern
932-4658 UP
932-4659 SP
932-4660 N&W
932-4661 SOU
932-4650 Undecorated
Walthers Dynamometer Cars are available only from Walthers dealers. To locate a dealer, use the dealer locator at www.walthers.com. Contact Walthers at 414-527-0770 or write Walthers, PO Box 3039, Milwaukee, WI 53201-3039.
