An Engine for Every Engineer

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By 1885, Gaar-Scott was building engines in sizes including 8, 10, 12 and 15 HP. Gaar-Scott's 1885 catalog referred to “The Great Atlanta Test Trial of Engines” of December 1881, where apparently the company's traction engine made quite a showing by towing an 11-ton load through several different tests. Within a few years, Gaar-Scott added a friction clutch, which landed Gaar-Scott and several other engine builders in a long, drawn-out court battle. (For more information on the lawsuit, see Robert T. Rhode's “The Mystery of the Lehmer Model,” Iron-Men Album, November/December 2002, “Lehmer Update,” Steam Traction, March/April 2003 and “Update on Isaac Lehmer,” Steam Traction, May/June 2003.) Though a few details, such as the axles under the firebox, were later dropped, in place were most features that for many years characterized Gaar-Scott's first style of engines.

Single-cylinder Wood- and Coal-burning Engines

These engines (Table 1) were built by Gaar-Scott from around 1878 to 1912, when the line moved towards exclusively rear-mounted engines (with a few exceptions). All classes of these engines were side-geared engines with wet-bottom boilers. Class E engines used locomotive slides with the flywheel on the left-hand side and with the cylinder mounted toward the rear of the engine. Class E engines were the earliest named style of engines introduced by Gaar-Scott.

Class F engines were identical to Class E engines with the sole difference that the cylinder and flywheel were mounted on opposite sides. In 1892, all Class E engines except the tiny 6 HP model were phased out, replaced by Class F engines. The Class G engines replaced the Class F engines themselves. The exception was the 10 HP Class F engine, which was not phased out until almost all side-geared engine production was discontinued at the end of 1912.

Class G engines were the later model side-geared, single-cylinder engines with bored Corliss-style crosshead guides. The rear-mounted cylinder was on the left-hand side; the flywheel, on the right-hand side. An alternative to the rear-mounted cylinder Class G was Class H, which was identical to Class E, with the exception of having a forward-mounted cylinder. Class E, F and G engines were also offered as portable engines.

Class J engines were compound-cylinder variations of the Class G models. By the early 1900s, Gaar-Scott reached the decision to build compounds in only the company's larger model sizes and only on Universal, dry-bottom boilers. One parts book indicates that at least a few 30 HP Class J models were built in 1903 and 1904, before engines of this size were switched to Universal boilers.

A curious fact about Class J is, from 1895 through 1896, various Class J engines (13 HP and 18 HP) used what Gaar-Scott called the “Wolfe” reverser. These engines were referred to as “Wolfe Compounds.” After trying out the Wolfe on only the Class J models for a few years, Gaar-Scott returned to the link reverse on all the firm's models.

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