Atlas O scale RS-3 diesel

This Alco RS-3 road switcher is a good-looking model that captures its prototype’s unique profile and can handle anything from passenger trains to yard switching. Made by Atlas O, the RS-3 is offered in two-rail DC or three-rail AC versions. Three-rail versions are available with factory-installed Lionel TrainMaster Command Control and RailSounds 4.0.

Alco’s RS-3 was a 1,600-hp road switcher introduced in May 1950. The prototypes were dual-service engines. Alco built 1,265 RS-3s for American railroads, 98 for Canadian customers, and 7 for Mexican lines. Many of these units remained in use for more than 50 years.

This model RS-3 closely matches a prototype drawing published in the Model Railroader Cyclopedia: Volume 2, Diesel Locomotives. The truck under the long hood is mounted a scale foot too far in from the pilot. The Atlas O model depicts a phase I RS-3 with its car- body filters located behind louvers.

This Trainman series model is more Spartan in its detailing than the premium Atlas O locomotives, but still looks good. It has a molded plastic body and cab with factory applied wire grab irons, handrails, and metal stanchions. The lengthwise stack represents an RS-3 with Alco’s original air-cooled turbocharger. A three-bladed fan is visible inside the upper radiator housing’s etched-metal grill.

Our two-rail DC sample has fixed pilots. The same detail parts are used on three-rail units with swinging pilots, so the vertical corner railings are short – they should reach the second step from the bottom.

The mechanism. The chassis is built on a stamped-metal frame. The die-cast pilots, trucks, and fuel tank add weight for traction. Each truck is driven by a vertical can motor with a flywheel. These motors serve as the truck kingpins and have a gimbal mounting that allows some rocking motion to negotiate uneven track.

The model rides on well-detailed die-cast Association of American Railroads type B trucks with separately applied bearing caps, brake cylinders, and other details. It has properly gauged and blackened nickel silver National Model Railroad Association RP-25 contour wheelsets. Each motor drives an outboard axle, and five spur gears transmit the rotation to the second axle on each truck.

Electrical system. The RS-3 has a large printed-circuit (PC) board mounted on insulators. Single golden-white incandescent lamps operate the headlight and number boards at each end. The two-rail model has a removable secondary PC board and connection points on the edges of the main PC board for converting the RS-3 to Digital Command Control, as outlined in the instruction manual.

Two wiring harnesses with sockets that connect to a DCC decoder are included with the model. Both harnesses have color-coded wiring that matches the NMRA Recommended Practice 9.1.1 color coding. A heavy-duty decoder is required, as the mechanism draws up to 6A of current.

Performance. The RS-3 started smoothly and ran quietly throughout its speed range. However, its 200+ scale mph top speed was well above the prototype’s 65 to 90 mph range (depending upon gear ratio).

The model’s 17-ounce drawbar pull is equivalent to 51 free-rolling cars on straight and level track.

Scale die-cast magnetic knuckle couplers are mounted at the proper height on both ends and are compatible with Kadee couplers. The metal couplers have insulated coupler boxes.

Our sample came smoothly painted in Rock Island’s late 1960s color scheme. All of the lettering is crisp and opaque.

These versatile units operated on railroads all over North America. O scale modelers of the first-generation diesel era will enjoy this well-done RS-3 model.

O scale RS-3 diesel
Price: two-rail DC, $229.95; three-rail AC, $369.95

Manufacturer
Atlas O
378 Florence Ave.
Hillside, NJ 07205-1799
www.atlasO.com

Description: Ready-to-run plastic-and-metal diesel

Road names: (Two road numbers each) Delaware & Hudson, Great Northern, Reading, and Rock Island

O scale RS-13 features
Cab window glazing
Die-cast metal magnetic
scale knuckle couplers
Drawbar pull: 17 ounces
Dual motors and flywheels
Eight-wheel drive and electrical pickup
Minimum radius, 36″
Wiring harnesses for Digital Command Control (DCC) decoder installation
Weight: 3 pounds 5 ounces