All Aboard!

Model steam locomotives gain realistic slow-speed control 

Model trains have traveled far since Lionel LLC, Chesterfield, MI, produced its first locomotive more than 100 years ago. Today’s trains continue to be designed with painstaking attention to scale detail, with the addition of unprecedented performance features as technology permits.

One of the latest innovations from Lionel is the patented Odyssey system speed control, which was introduced in the Union Pacific Challenger (the inaugural Joshua Lionel Cowen series locomotive) and has since been incorporated into other large high-end steam engine models. One feature of the system enables a locomotive to detect a layout’s grades and curves automatically, and then compensate by increasing or decreasing speed. 

Odyssey calls for the locomotive’s motor to perform reliably at low speeds and to deliver consistent rpm. LO-COG series 9000 brush-commutated DC motors from Pittman, Harleysville, PA, have kept Lionel on track in meeting these demands as well as delivering the power required to drive both models of the top-of-the-line (and limited edition) Challenger locomotive. Lionel selected this motor after extensive in-house testing and evaluation. An added bonus: the specified Pittman motor is virtually off-the-shelf.

The Trains

The two Challenger series units are 32-in. long models that feature die-cast boilers, frames and tenders. Both are manufactured with impressive realistic authenticity in scale detail “never before offered by an O-gauge manufacturer,” according to Lionel. Special features include Lionel’s TrainMaster command control for radio-controlled, hands-free operation; and articulated RailSounds, a sound effects package with features like CrewTalk, TowerCom, DynaChuff and MultiWhistle. In both of the Challenger models, all 12 of the locomotive’s driving wheels are powered, propelling the locomotive to realistic top speeds of 60-80 scale mph.

The Motor

Lionel’s decision to proceed with DC motors for the Challenger series is further evidence of the company’s much broader move from AC to DC motors in recent years. Brush-commutated DC motors today can be found in all of the company’s larger (20- to 30-in.) Winding voltage was raised from 12 to 15.1 VDC to accommodate requirements for TrainMaster command control. 

The 2.4-in. long, 1.58-in. dia. motor weighs 10.1 oz and promotes smooth, quiet operation and reliable long life. The seven-slot armature is skewed to minimize magnetic cogging, enhancing performance even at the low-speed operation. The motor can achieve continuous torque up to 6.1 oz-in., peak torque to 41.3 oz-in. and speeds up to 6150 rpm, all of which were among the factors carefully considered by Lionel when setting specifications and selecting vendors for the Challenger project. 

Motor construction features include 2-pole permanent magnet stators (ceramic magnets enclosed in heavy-gauge steel return rings), standard copper-graphite brushes, diamond-turned commutators that promote brush life, precision-ground hardened stainless steel shafts, silicon-steel laminations and self-aligning sintered bronze bearings. Taken together, these features have helped to ensure motor integrity and reliability in service. 

Lionel’s ongoing relationship with Pittman will continue to grow, due to the resurgence of model railroading as Lionel enters its second century of operation. “Every new large steam locomotive model that Lionel has made in the past three years, and all of those presently on the drawing board, feature a Pittman DC brush motor,” adds Webster. “We’ve found that the quality and performance inherent in Pittman products add value to our product line.”

For more information:

Circle 349—Pittman, or connect directly to their website via the Online Reader Service Program at www.RSLeads.com/?112df-349