S gauge

S scale
Scale	³⁄₁₆ inch to 1 foot
Scale ratio	1:64
Model gauge	0.883 in (22.43 mm)
Prototype gauge	1,435 mm (4 ft 8 ¹⁄₂ in) standard gauge

S scale (or S gauge) is a model railroad scale modeled at 1:64 scale, S scale track gauge (space between the rails) is 0.883 in (22.43 mm). S gauge trains are manufactured in both DC and AC powered varieties. S gauge is not to be confused with toy train standard gauge, a large-scale standard for toy trains in the early part of the 20th century.

S Scale is one of the oldest model railroading scales. The earliest known 1:64 scale train was constructed from in 1896. The first working models appeared in England in the early 20th century. Modeling in S Scale increased in the 1930s-1940's when CD Models marketed 3/16" model trains.

American Flyer was a manufacturer of Standard Gauge and O gauge "tinplate" trains based in Chicago, Illinois. It never produced "S" Scale trains. Chicago Flyer was purchased by A.C. Gilbert Co. in the late '30's. Gilbert began manufacturing "S" scale trains in around 1939 that ran on three rail "O" gauge track. This was known as 3/16" O Gauge. Gilbert stopped producing trains during WWII. When the war ended, Gilbert began producing true "S" Scale "S" Gauge trains in 1946.

The term "S Scale" was adopted by the National Model Railroading Association (NMRA) in 1943 to represent that Scale that was half of 1 gauge which was built to 1:32 scale. A.C. Gilbert's improvements in 1:64 modeling and promotions of S gauge largely shaped the world of 1:64 modeling today.

S gauge entered what many consider its heyday in 1950s (although there is more available in S scale today than was available during this period) . However, during that period, Lionel outsold American Flyer nearly 2 to 1. American Flyer's parent company went out of business and the brand was sold to a holding company that also owned Lionel in 1967.

Lionel re-introduced S gauge trains and accessories under the American Flyer name in 1979. Another S manufacturer, American Models, entered the marketplace in 1981 and is now also one of the major S suppliers. S-Helper Service, another major S gauge manufacturer of locomotives, rolling stock, track and other products, began operations in 1989 and delivered their first S products in 1990. And while the S scale market has seen a number of brass model manufacturers, today the major brass model supplier in S scale/S gauge is River Raisin Models. Today's S gauge/S scale modelers have a greater selection and higher quality products, from a wide range of manufacturers, that at any time in the past. In addition to the basics of locomotives, rolling stock, and track, various manufacturers now offer S scale structures, detail parts, figures, other scenic items, bridges, and more.

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