The Climax was one of the three major American geared steam-locomotive families developed for logging, mining, quarry, and industrial railroads.
Climax Manufacturing Company of Corry, Pennsylvania produced locomotives over roughly four decades and built more than a thousand examples.
The earliest Class A locomotives looked unlike conventional locomotives, combining a boiler and drive machinery on a relatively simple platform frame.
The later Class B became the most familiar Climax form, using a horizontal boiler and inclined cylinders driving a transverse crankshaft.
Power then passed through gears to a longitudinal driveshaft located near the centerline of the locomotive.
The center shaft transmitted power to geared truck axles, allowing all powered trucks to swivel beneath the frame.
Class C locomotives extended the design to three trucks for larger size and greater fuel and water capacity.
Climax locomotives were valued on rough track because the trucks could conform to uneven alignment while the gearing delivered high tractive effort at low speed.
They should not be described merely as copies of the Shay. Historical research on the design shows that Climax development followed its own engineering path, even though the machines competed in the same market.
For TransitSatellite, a generic Climax page must distinguish Class A, B, and C layouts. One 3D model cannot truthfully represent the entire family without specifying the class.