About S Scale

S Scale and S Gauge: A.C. Gilbert American Flyer and Others

S scale is often regarded as synonymous with the American Flyer brand of model railroad trains. S scale is defined as 1:64 or 3/16ths of an inch to one foot. S scale's track gauge is an unusual 0.884 inches. S scale trains are manufactured in both AC and DC varieties, but unlike O scale both types use two-rail track. Once on the brink of extinction, S scale railroading has experienced a renaissance in the last two decades. This is one of the few scales in which I own no pieces. But I do...MORE admire some of the fine work being done in this somewhat exotic scale.
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    The S Scale Standard

    The S letter designation for the scale was defined by the National Model Railroading Association (NMRA) in 1943. S scale (1/64) was specified to be one-half of One scale (1/32). One scale is another exotic older scale. Incidentally, the name O scale actually derives from the fact that it was originally called Zero scale, because at 1/48 it was smaller than One scale. In the early days, this scale was commonly referred to as 3/16th scale.
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    S Scale vs. S Gauge

    In model railroading "scale" refers to the relation of the size between a model and its original prototype. The term "gauge" refers to the space between the rails of the train track. For more see Scales and Gauges. While beginners often use these terms interchangeably, American model railroaders usually refer to the "scale" they work in, while UK railway modellers will talk of their "gauge". Ironically, the usages of the terms "gauge" and "scale"...MORE have become culturally reversed. The National Association of S Gaugers, Inc. (NASG) is an American institution, while the S Scale Model Railway Society is based in the UK. This may be due to the fact that early 3/16th scale models shared 1.25" gauge three-rail track with 1:48 O scale trains.

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    Early History

    While some historians write that there were modelers in the UK working in 3/16th scale prior to the 1930s, the emergence of 3/16th scale in America seems to have happened independently of their efforts. And all I have read indicates that the early UK models were unmotorized models for static dislay.

    In the mid 1930s Cleveland Models introduced 1:64 scale model railroad trains in the United States. For a time, 3/16th scale was referred to as "CD" scale for "Cleveland Designed". CM...MORE produced static display models, but powered chassis kits for them soon followed. The best known CM locomotives were a PRR 0-6-0 switcher and a Chicago Great Western 4-6-0 Ten Wheel. Today one running CM locomotive is still purported to exist.
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    A.C. Gilbert and American Flyer

    In 1938 A.C. Gilbert (later the manufacturer of Erector Sets and other educational toys) acquired The American Flyer Manufacturing Company (established in 1910). Up until that time American Flyer manufactured O scale model railroad trains. After they were acquired by the A.C. Gilbert Company in 1939 the brand name "American Flyer" was used on A.C. Gilbert's new 3/16th scale trains. It is my understanding that Gilbert obtained permission to manufacture in the scale from Cleveland...MORE Designs. I find no record of Gilbert producing any O scale trains from that time forward. Interestingly though, their HO trains were sold under the name Gilbert HO, not American Flyer. A.C. Gilbert continued to manufacture American Flyer S scale trains until 1966.
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    Prototypical Accuracy

    Although A.C. Gilbert began producing 3/16th scale trains in 1939, these were not true S scale models. These early trains used O scale 1.25" gauge track. Model train manufacturer Marx soon followed with their own 3/16th scale trains for O gauge tracks. This led to the introduction of O27 trains, though American Flyer never offered O27 products. But these trains established Gilbert as a pioneer of prototypically correct scale model railroading. Unlike other fanciful toy trains of the day,...MORE Gilbert's 3/16th scale locomotives were scale models of the PRR K5 class 4-6-2 and the NYC J3 "Hudson". In 1946, keeping with this push towards realism, American Flyer trucks and mechanisms were changed to 0.884" gauge and true S scale/gauge was born.

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    The Lean Years

    From the demise of A.C. Gilbert in 1966 through the 1970s were lean years for S scalers. I'm told that interest in S scale was probably kept alive initially by a small newsletter called the "S Gauge Herald". Later the National Association of S Gaugers (NASG) was formed. These organizations, and another small magazine called the "S Gaugian" provided a the means for S gaugers to exchange information and keep abreast of the offerings of small S scale manufacturers like Kinsman,...MORE Miller Laboratories, and Enhorning. Apparently most of the products were kits. This is analogous to the state of TT scale in America today. However, as far as I can tell, unlike TT scale there were no ready to run products being offered in Europe.

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    The S scale renaissance began around 1980 when American Models appeared on the scene with an S scale ready to run EMD FP-7 diesel. They soon followed up with a set of streamlined passenger cars, and later freight cars. This paved the way for a return of S to the model railroading mainstream. As the makers of TT scale in America apparently never learned, no scale can succeed without ready to run products. Since these initial offerings by American Models there has been a slow but steady increase...MORE in the availability of S Scale ready to run products.
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    American Flyer Today

    In 1967 the American Flyer brand name was acquired by the owners of Lionel, LLC. While the American Flyer brand name fell into disuse during the lean years, the renaissance in S scale has induced Lionel to offer American Flyer S scale trains again. In 2008 the American Flyer line occupied about a dozen pages in the Lionel catalog. Some modern American Flyer offerings are now equipped with Lionel's TMCC digital controls and RailSounds audio systems. But they also offer recreations of a few...MORE classic American Flyer products too.
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    Other Modern S Scale Manufacturers

    Today S scale trains and accessories are manufactured by a number of companies. Most notable among these are American Models, who started the renaissance, and S-Helper Service Inc. Both of these companies advertise their trains as "American Flyer Compatible". S-Helper offers very nice looking starter sets with their own integrated roadbed track, S-Trax. Products from both of these companies appear to be competitive with better O scale and HO scale products in detail, quality and price.

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    S Scale in Brass

    For the discerning collector, River Raisin Models, Pennsy 'S' Models, Overland Models, and others make finely detailed S Scale trains in brass. Of course, these come at prices you would expect to pay for brass. But as the saying goes, there's no such thing as a free lunch.
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    Some Thoughts on S Scale

    S scale has made an impressive comeback in recent years, but among many model railroaders it still has something of an exotic mystique. Though my personal preference favors smaller scales, this is because I have very limited space for train layouts. Having said that, if you are familiar with my writings, you know my affinity for TT scale reflects my on fascination with the exotic. While I always consider space to be a major consideration in selecting a scale, if you have the room I think that S...MORE scale is well worth investigating. If I had the space I might well be putting together an S scale layout myself.
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    Many thanks to S scaler Pieter Roos for his assistance in revising this article.