Review by Harry K. Wong/photos by the author
Postwar economic expansion in the 1950s brought much change to North American railroads. The transition from steam-powered locomotion to diesel-electrics was nearly complete on most Class I roads by the middle of the decade thanks to the efforts of Electro- Motive Division (EMD) of General Motors, Fairbanks-Morse, and legacy locomotive manufacturers such as Alco Locomotive Company, Lima, and Baldwin—all of which by then were producing diesel locomotives in quantity.
The RS-18 is the Canadian sister to the American-built Alco RS-11. Designed as the archrival to EMD’s GP9, Alco introduced the four-axle 1,800hp RS-11 to U.S. customers in February 1956. Ten months later, Alco’s Canadian partner Montreal Locomotive Works constructed its first RS-18. Perhaps the most noticeable difference is the lack of “notches” at the top corners of the short and long hoods as seen on the RS-11. Instead, a simple radiused corner made for a cleaner appearance on the RS-18.
At the end of production in 1968, 351 RS-18s were produced, with 225 units going to Canadian National, and 72 units delivered to Canadian Pacific. Other original owners include the Pacific Great Eastern, Cartier Railway, Roberval & Saguenay, and others.
With a thirteen-year production run and a variety of service demands to address, it should be no surprise that there were a significant number of detail variations between units over the years. For this first release, the Rapido Trains model echoes the wide variety of details seen on these locomotives during their service lives. Between the different paint schemes, one will find different trucks, different long and short hoods, different pilots, four different fuel tanks in addition to road or assignment-specific details, yet sharing a common frame and distance between truck centers.
Built for service on branch lines with lightweight rail, RS-18s received lightweight trucks with an 8’10” wheelbase without secondary leaf springs, whereas most “standard” units received standard Type B trucks with a 9’4” wheelbase. Canadian National rostered 131 “standard” RS-18s, and 94 “lightweight” models.
In 1968, with twenty-five new lightweight passenger cars from Hawker-Siddeley on order, CN modified six RS-18s previously assigned to passenger service by installing head-end power (HEP) equipment into the short hood to supply power to the HVAC and lighting in the new passenger cars. As space was at a premium, the short hood was extended over the front walkways to accommodate the new Cummins HEP generator and General Electric alternator. Rechristened in an all-new red-orange and light gray paint scheme, these snappy-looking locomotives were assigned to CN’s new “Tempo” regional passenger trains for service between Toronto and points in Southwestern Ontario. Our sample for this review represents CN 3153, one of two Tempo RS-18s that had its HEP equipment removed during collision repairs.
As with most premium locomotives these days, purchasers will find the Rapido RS-18 shipped securely within layers of plastic and foam encased within a thick paper box emblazoned with appropriate box art. A most welcome surprise is the snappy appearance of the multi-page users’ manual. The cover of the manual is a close reproduction of the cover of a real MLW RS-18 operator’s manual. Bravo!
The handrails are of a hybrid metal and plastic construction where the stanchions are literally molded around the metal handrails in the manufacturing process. This results in a relatively sturdy and straight set of handrails down the side of the locomotive. Given the plethora of details on this model, one must still exercise caution in handling.
The paint and decoration are exquisite, with no flaws noted. The MLW builder’s plate is especially exquisitely rendered. The list of fine details is long, including separately applied door handles, m.u. hoses, radio antenna, sunshades, grab irons, cut levers, lift rings, etched metal screens, walkway tread and much more. The etched metal drop steps are positionable either up or down. Beneath the side sills, a robust suite of underbody details is provided, including separately applied rerail frogs, dual air reservoirs complete with drain lines, and a full complement of traction motor and HEP cabling under the side sills.
About the only detail improvement I would suggest is for the edges of the transparent cab mirrors to be painted or pad-printed in the appropriate color. Out of the box, the mirrors leave a bit of “unfinished’ contrast to the rest of the locomotive. This can also be remedied by the modeler with a small paint brush and a steady hand.
DCC Sound, Operation and Lighting
Beneath the shell and deck is the expected can motor with flywheels powering the trucks, all mounted in a diecast chassis. Tractive effort is delivered from the motor/flywheel combo via driveshafts to a worm gear atop each truck assembly driving all axles. On this sound-equipped model, operation is mediated through a Loksound version 5 DC/DCC sound decoder provided by ESU. Full separate control of number boards, headlights, classification lights and more is provided and fully documented in the users’ manual. A great feature is the illuminated ground light on each side above the front truck. For those of you unfamiliar with this type of illumination, ground lights are used by the engineer at night to better sense locomotive movement at low speeds by projecting light onto the ballast below.
Lastly, the coolest feature for this model not yet seen on other HO diesels is a control stand with backlit illuminated gauges inside the cab for the engineer. As this specific road number represents a locomotive with dual controls, you are treated to an illuminated control stand on both sides per the prototype! Yes, you’ll want to dim the lights a bit in your layout room to appreciate these features. Modern modelers will enjoy ditch lights on the CP models with the eight-inch-wide hood striping. Non-Sound DCC/Silent versions are equipped with a 21-pin plug for conversion to DCC operation. For those who prefer silent DCC control, Rapido recommends ESU decoder 54615 to ensure proper operation of the many lighting functions available on the locomotive.
Metal Kadee-compatible couplers are preinstalled, and both ends measured out at the proper height against our Kadee coupler gauge. I did notice that the front pilot plow hung a bit low above the rail, with only about .015-inches of clearance, so I popped off the front pilot plow with a small screwdriver, redrilled the mounting points with a #61 drill bit and remounted the plow a tad higher with a few tiny drops of ACC.
Weight and Operation
For a four-axle diesel, our test sample weighs a respectable 14.375 ounces. On the test stand, we measured a drawbar pull of 2.75 ounces. Under DCC operation, low speed operation was silky and silent even without the sound engaged. With F8 pressed, the locomotive springs to life with the gutsy utterances of an Alco 251B prime mover accompanying the smooth operation. For those of you who prefer DC control, our example awoke first with lighting and prime mover sounds, and then initiated movement after additional throttle was applied. Under 12VDC operation, there is directional lighting for the headlights, including the class lights. Nearing a stop, the squeal of the brakes is wonderful, under either DC or DCC operation.
The RS-18 was MLW’s most successful four-axle locomotive and a common sight throughout Canada, with some operating into the U.S. in later years and acquired by short lines. Given the extremely high level of detail and operation with this HO rendition by Rapido, this model stands as an essential roster addition for fans of Canadian motive power. We hope that Rapido will offer additional (low nosed?) variations of this popular locomotive in the future. We’ll be waiting!
MLW RS-18 Diesel Locomotive
Canadian National (as-delivered green)
Canadian National – noodle
Canadian National (stripes)
Canadian National ‘Tempo’
(maroon & grey – script lettering)
(maroon & grey – roman lettering)
Canadian Pacific (5” nose striping)
(8” nose striping with ditch lights)
Undecorated – CN or CP versions
500 Alden Road, Unit 21
L3R 5H5 Canada