Bulletin: *Shay*


The Shay locomotive was the most widely used geared steam locomotive. The locomotives were built to the patents of Ephraim Shay, who has been credited with the popularization of the concept of a geared steam locomotive.

Shay locomotives had regular fire-tube boilers offset to the left to provide space for, and counterbalance the weight of, a two or three cylinder "motor," mounted vertically on the right with longitudinal drive shafts extending fore and aft from the crankshaft at wheel axle height. These shafts had universal joints and square sliding prismatic joints to accommodate the swiveling trucks. Each axle was driven by a separate bevel gear, with no side rods.

The strength of these engines is that all wheels, including, in some engines, those under the tender, are driven so that all the weight develops tractive effort. A high ratio of piston strokes to wheel revolutions allowed them to run at partial slip, where a conventional rod engine would spin its drive wheels and burn rails, losing all traction.

Shay locomotives were often known as sidewinders or stemwinders for their side-mounted drive shafts. Most were built for use in the United States, but many were exported, to about thirty countries, either by Lima, or after they had reached the end of their usefulness in the US.

This ESU LokSound Select File has 5 Whistles, which can be changed by setting CV48 to a value between 0 and 4.

Key Function Soundslots Volume CVs Volume value
LightDirectional headlights / Dynamo629930
F2Playable whistle3275128
F3Short whistle16379128
F4Coupler Clank529190
F6AUX1 [1], Firebox
F7Switching mode
F8Prime mover, Prime mover, Johnson bar, Hiss and startup
F9Open cylinder cocks ON/OFF (Manual Control)
F10Air Pump7307100
F11Water Syphon10331128
F12Coal Shoveling1537180
F13Water Fill from tank1234740
F14Brake Set/Release (Auto)11339128
F17Safety Valve1940390
F18Sanding Valve14363110
F19Oil Burner1335580