Atlas HO scale EMD SD35 diesels feature railroad-specific details

A trio of excellent HO scale SD35 road switchers has been released as Atlas Master Series Locomotives which feature superb performance, dual flywheel drives, dual-mode DCC decoders, and specific railroad detailing. They represent the Electro-Motive Division’s standard low-nose SD35 road freight locomotive; a high-hood version built for the Norfolk & Western RR and the Southern Ry.; and an SDP35 passenger unit owned by Atlantic Coast Line, Louisville & Nashville, Seaboard Air Line, and Union Pacific.

Electro-Motive Division introduced the prototype SD35 as part of its “35 line” of locomotives in 1964. It’s a six-axle, 2,500-hp, heavy-duty freight locomotive; the SDP35 played a similar role in passenger service. Louis Marre’s book Diesel Locomotives: The First 50 Years states that 360 SD35s (including 190 with high hoods) and 35 SDP35s were built before production ended in January 1965. Prototype drawings were published in Simmons-Boardman’s 1966 Car and Locomotive Cyclopedia. The Atlas SD35s and SDP35 closely match these drawings.

Atlas introduced its original SD35 models 27 years ago, but this new generation is far superior to its predecessors in both performance and detail.

Like most of Atlas’ recent models, the locomotives come fully assembled except for their sunshades and the end railings, which simply press into place. A printed 8½” x 11″ sheet has exploded isometric drawings on both sides showing all of the different chassis and body detail combinations. A second page explains the model’s dual-mode decoder functions with a reference to the Atlas Web site at www.atlasrr.com for further technical information.

After studying the drawings and the three samples, I’m sure these models are some of the most sophisticated HO plastic locomotives to date. Atlas has included nine different SD35 body shells, three SDP35 shells, three sill assemblies, and numerous separate optional detail parts in the tooling. Various combinations of these parts are then factory assembled into locomotives with appropriate details for each paint scheme.

Mechanically, the SD35s follow the design Atlas introduced with its revised GP40, which was reviewed in the October 2000 Model Railroader. The chassis consists of a heavy cast-zinc alloy frame with a can motor above the fuel tank. Turned-brass flywheels are pressed on both ends of the motor shaft, along with universals which drive both trucks.

All 12 wheels are driven and pick up electrical current.

The pilot and sill assembly slips over the metal frame, then the hoods and cab lock into place with concealed latches. All three versions are literally covered with fine detail parts, which are added separately and held in position by friction or tiny concealed latches. Most modelers will be pleasantly surprised at the thin cross-sections and quantity of these details, including an engine crew in the cab.

All three locomotives ride on replicas of EMD’s six-wheel Flexicoil trucks, which have colored acetal plastic sideframes with excellent detail. The brake cylinders, speed recorder cable, and sand lines are added parts. All of the blackened nickel-silver wheelsets have RP25 contours and match the National Model Railroad Association standards.

The printed-circuit board mounted on top of the motor includes the control circuit for the reversing headlights, which operate in either mode.

The Atlas dual-mode decoders conform to the NMRA’s DCC (Digital Command Control) standards. They can be programmed for 14-, 28-, or 128-step speed control (14 steps is the default setting). Each decoder will handle 1 amp of continuous motor current and has a pair of 200ma.-capacity outputs to operate ditch lights, dimming headlights, or other similar functions. The decoders support advanced consist control, extended addressing, and all forms of programming as specified in NMRA Recommended Practice 9.2.3.

Removing the dynamic brake housing provides easy access to the decoder, which has a small jumper plug that can easily be moved to switch the model between conventional DC and DCC.

Decorated locomotives come factory programmed to the DCC channel that matches the last two digits in the engine number. Thus CSX no. 4586 operates on DCC channel 86.

The SD35s performed flawlessly on conventional DC, starting and accelerating smoothly and quietly. All three samples gave virtually identical meter readings. On DCC, they began moving on throttle step one and performed similarly through all 14 speed steps. All three samples produced a drawbar pull equivalent to 62 free-rolling freight cars on straight and level track.

Accumate magnetic knuckle couplers are body mounted in coupler boxes which are secured with small screws. Our samples had the correct coupler height.

The decoration on our samples was uniformly excellent with smooth, even coats of paint that didn’t obscure any detail. The lettering is clear and even red DANGER 600 VOLTS warning labels were readable on the hood doors.

This group of SD35 models certainly pushes the standard of specific railroad detailing on road switchers well beyond anything we’ve seen before. Their superb detailing, finish, and top performance are bound to make these locomotives popular.

HO EMD SD35 road switchers

Price: $139.95

Manufacturer:
Atlas Model Railroad Co. Inc.
603 Sweetland Ave.
Hillside, NJ 07205-1799
www.atlasrr.com

Description:
Plastic and metal locomotive

Features:
Accumate knuckle couplers
Cab interior
Directional headlights
Drawbar pull: 4.48 ounces
Dual flywheel drive
Dual-mode decoder with jumper plug for DC or DCC operation
Engine weight: 16 ounces
Metal grab irons
Minimum radius: 18″

Road names:
(Two numbers each plus unnumbered)

• Standard SD35:
  CSX (nos. 4527, 4586)
  Pennsylvania (nos. 6016, 6025)
  Southern Pacific (nos. 6904, 6915)
  Western Maryland (nos. 7434, 7435)
  Undecorated
• High-nose SD35:
  Norfolk & Western (nos. 1505,1521)
  Southern (nos. 215k, 3008a)
  Undecorated
• SDP35:
  Seaboard Air Line (nos. 1105, 1114)
  Union Pacific (nos. 1402, 1407)
  Undecorated