The Tunnel Company operated a two-foot gauge electric railway in a 62-mile network of tunnels located forty feet below Chicago’s famous downtown "Loop" district. At its peak, the system had 149 four-wheel "motors" (electric locomotives) and over 3,000 freight cars. Traffic largely consisted of parcels, coal, and heating ash. The railway connected the city’s major department stores, large office buildings, some factories, and the seemingly countless railroad freight houses and trucking terminals that ringed the Loop.

Constructed largely between 1900 and 1906, the Tunnel Company’s promoters had hoped to divert commercial freight traffic off of the congested streets and onto their railway. These expectations were realized only to a limited extent, resulting in operations ceasing in 1959.

Having little in the way of tools, and not having a home workshop, I was able to enlist the help of several other members of the Milwaukee Light Engineering Society. First I discussed my idea for building a 7-1/2" gauge model of one of the Tunnel Company’s distinctive mine-style motors with Brad Smith. Intrigued, he agreed to help out and we collaborated on the type of unit to be modeled and made sketches based on my extensive file of information on the prototype. He determined that the Class 30 "open gondola type" mine motors built by the Columbus, Ohio-based Jeffrey Manufacturing Company would yield the best result. Built in 1906, the Jeffrey’s were 4-wheelers that weighed in at about 6 tons and measured about 10 feet long.

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Once the model’s dimensions were determined, Brad made use of a local technical school foundry to cast the motor’s raised side panels. Meanwhile, fellow MLES member Tom Artzberger (Hartford Shops) lent his expertise and machine shop, cutting and welding the half-inch thick steel plates that make up the motor’s side and end panels, and providing the wheels, couplers, motors and control system that would go in to the finished model. Assembly began in October 2006 in Tom’s shop. By the end of the second day-long session, the bulk of the assembly and the control system work had been completed.

The action then moved over to the garage workshop of a third MLES member, David Gehrke (West Bend Shops) where completion of the motor, and construction of the rolling stock took place. Given the motor’s tiny outline, it was necessary to build a parcel car to hold the batteries, charger, and a rerailing lever (necessary because the motor is HEAVY). For the motorman’s riding car, one of the Tunnel Company’s stake and chain-sided merchandise car designs was selected and modified.

In between assisting Dave who welded the car frames and built-up the car bodies, I searched out some of the odd-parts that would be needed to complete the train. One challenge was that machine tools were not available at this point although we did have some metal fabrication equipment. Some of the detail items that needed to be scrounged-up or cobbled-together out of available materials included 406’s handbrake wheel (a brass water valve wheel was found on E-bay) and the radial coupler pockets for the battery and riding car. Perhaps the most challenging items to find was something – anything - that could be readily modified to create the front headlight and rear flood light reflector for #406. The front headlight was made using the kerosene reservoir from an Adlake lantern, while the rear flood light housing was made from an iron ladle.

Marty Brown, a Chicago area HO model railroader then made various detail parts, including the trolley pole and a dummy controller for the miniature motorman.

On March 25, 2007, the unfinished but complete train consist was placed on Dave Gehrke’s home track to determine its tracking and riding qualities, and then it was time to paint the consist in the company’s plain black livery. Work was wrapped up a day before Easter. This was certainly a record of sorts.

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For more information about the prototype, pick up a copy of The Chicago Tunnel Story by Bruce Moffat.
Visit cera-chicago.org for more information.

Written by Bruce G. Moffat

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