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O Gauge Tinscale Facts

O Gauge: Scale, Gauge, Semi Scale and O27

O Gauge is not a consistent scale, but envelops various scales and non-scales all made to run on 1 1/4 inch gauge track. Unlike S, HO and N, which tend to have specific scales, O is a medley. #1 Gauge (a.k.a. G) is the only gauge which is as diverse as O, what with trains in 1/32, 1/29, 1/24, 1/22.5 and 1/20 scales all using the same track.

The G scales are pretty much codified. This is not the case for O.

The original O trains, like their Standard, Wide and #1 Gauge counterparts, were not made with an eye toward scale. They were toy trains. Scale was a difficult standard during the early 1900s. Toys were made for playability. Many were mere representations of real trains. Some were models of the real thing in name only. Dimensions, details and colors were dropped at will. Alteration in form and hue was commonplace. The only consistent features were the track gauges. Scale played little or no role.

Refinement generally grows with the ability to produce it. As technology improved, so did the ability to make more realistic trains. That included scale. While Lionel, Ives, American Flyer, Dorfan and Marx continued to make off-scale toy trains, a handful of specialists produced scale kits. Many of the kits were accessories to turn existing toy trains into scale models. A few produced an entire scale model outright. The accepted scale for O varied. In Britain, it was 1/43.5, based on the standard track gauge. In America, I/48 was accepted, despite a minute difference in scale track gauge and the 1 1/4 inch size of O. 1/48 scale was convenient, since it meant a scale foot of 1/4 inch. Known also as "quarter-inch scale," 1/48 proved itself a winner. (HO, which stands for "half-O, was based on the British O).

A scale curve for O was developed, it being a 72 inch diameter circle. That did not sit well with toy train makers. One of the selling points of O gauge was that it allowed more action in less space. The tight O 31 and O 27 curves were integral to space consideration. O 72 was too wide, and negated any advantage, especially since it was a wider arc than the Standard gauge on which O was intended as an improvement. Thus, O gauge went in three directions: smaller trains running on O27, regular trains to run on O31, and a handful of scale models built for O72.

Enter A.C. Gilbert, who bought American Flyer and devised a brilliant concept. Since it was impossible to make 1/48 passenger cars and long locomotives capable of handling an O31 curve, why not down-scale? Gilbert figured on using 1/64, or 3/16 inch scale (3/16 of an inch equals one scale foot). His scale trains were 1/64 models, made to run on O gauge track. They worked, since even long passenger cars and locomotives could handle the tight 31 inch curves. Lionel and Marx both leaped on the idea. Marx developed an entire Scale line of tinplate cars using the 1/64 standard.

World War II interrupted toy train manufacture. After the War, American Flyer emerged with its 1/64 S gauge, a 7/8" gauge that suited 3/16 inch scale. It was out of the O gauge entirely. Marx introduced its plastic cars, along with its older lines of scale tinplate and toy tinplate trains. The plastic cars were made in the 1/64 scale, on O trucks. What stood out with Marx's scale cars is that their trucks and wheels were smaller, thus having a height commensurate with 1/64. Lionel brought out an O27 line that included 1/64 cars on its standard O trucks. Both Lionel and Marx produced most steamers in a scale close to 1/64. This is how O27 was originally associated with 1/64 over O. To date, a true O27 car is based on the 1/64 rather than 1/48 standard.

Lionel introduced its regular line of O gauge cars. These were slightly smaller than scale, yet larger than O27. The standard O car became the 6464 boxcar. It was notably wider and longer than 1/64 cars, yet smaller than true 1/48 scale models. The "classic" cars followed suit. They were a middle ground between O27 and pure 1/48.

Scale emerged from time to time. Notable in Lionel's "Standard O" line. However, pure O scale was mainly a thing for two-railers. Three-rail O found itself with 1/64 over O, the 6464 semi-scale, and the 1/48 pure scale item that emerged occasionally. Then there were odd pieces, such as handcars, that might be as large as 1/24 scale.

Though many diesel locomotives were made to scale dimensions, the cars remained a bit small. It is only recently that 1/48 scale became a big issue for O gauge. Currently, scale pieces are available through MTH (Premier line), Lionel, K-Line, Williams, Atlas, Weaver and 3rd Rail. MTH's Railking Line, originally promoted as "O27," tends to be a larger O gauge based more on a 1/48 standard than 1/64. Lionel still produces its semi-scale and O27 pieces, while K-Line's Classics embody the common sizes akin to Lionel as well as pure O27 pieces. For the O gauger, it helps to remember that Railking tends to run taller and closer to 1/48.

Smaller Trains, More Action

Tinscale is about action, and realism is a matter of appearance rather than precise scale dimensions. We are not out to replicate the world in minute scale, but get the feel of it through realistic models which look good together.

O gauge's great advantages are the tight radius curves which allow for more action in less space. Inch for inch, an O layout will have more action than HO. The smaller HO trains use a 36-inch diameter curve, as opposed to the 31 inches of O or the 27 inch O27. The place where O needs space is in straightaways, since O trains are notably longer than HO regardless of turn radius.

Though club layouts tend to run long, the average home layout is restricted. O layouts run from as small a 4' by 8'. Getting more action on a pike is partly in design, partly in the choice of trains. For instance, a trolley layout on a 4' by 8' layout could be very active, since the trains consist almost entirely of single, short motor units. A passenger layout could be lame, since scale passenger cars run 18 inches in length.

O scale does not run well on small layouts. However, semi-scale and O27 can be very active.

Conventional O Gauge

The O gauge hobby has become institutionalized in such a way that certain car and loco types are the norm, despite prototypes to the contrary. Tinscalers are willing to overlook prototype precedent when it suits them, and this trend has produced O gauge standards that leave hardcore scale modelers perplexed.

Vista Domes: the Vista Dome passenger car was used by Western Railroads for their crack streamliners. Most notable were the Santa Fe's Super Chief and the finer Union Pacific liners. Vista Domes were not used east of the Mississippi, since Eastern tunnel and bridge clearances were too short for them. Nonetheless, every road name gets Vista Domes in O gauge. You will find them in Pennsylvania, New York Central and B&O liveries. And yes, they are even found in the Lackawanna streamliner sets, despite the fact that such a car could never clear the Jersey City or Nay Aug tunnels. Vista Domes are expected among O gaugers, regardless of road names.

Pointed Observation Car: the end cars varied among railroads. Streamliners might have rounded, flat or pointed ends. For instance, the Phoebe Snow had a flat-ended Observation Car. Nonetheless, aluminum streamliners for O gauge are almost invariably arrow-ended, a la the NYC Empire State Express. Though recent makers have accommodated other observation car types, the pointy streamliners are still sold in droves.

N5 Caboose: the Pennsylvania and Lehigh Valley used the short N series cabeese with their porthole windows. Conrail inherited them. The N5 was a Pennsy invention, and it did not get around to other railroads aside from those already mentioned. That may be the real world, but in O gauge, the N5 was all over the place. You name the road, and they had the N5. Lackawanna, CNJ, Chessie, Santa-Fe ......where else can you find a limited-use caboose in unlimited roadnames? Thus the N5 is here to stay, in whatever road names are out there.

Atlantic & Columbia: The 4-4-2 and 2-4-2 locomotives had their limitations. Some roads never had Atlantics, some only had them in Camelback versions. The Columbia was even more limited in use. Most 2-4-2 locomotives were for narrow-gauge pikes. NOT in O gauge! You can find the Atlantic and Columbia in a variety of road names, whether their prototypes had them or not.

Boom Tender Caboose: the crane tender caboose is a beloved part of any O gauge maintenance of way train. Never mind that most boom tenders were converted gondolas, or that the "standard" work caboose was not standard at all! Most roads pressed standard cabeese into maintenance of way service, plain and simple. Nonetheless, the boom tender / work caboose has entrenched itself in O gauge, so that making a crane in any livery demands a matching boom tender caboose. So strong is this duo that it's even replicated in N scale! Boom tenders are also used as Searchlight Cars, by the way.

Crane Colors: some roads so were embarrassed at having to call out the heavy cranes that they didn't bear company markings prominently. This rang especially true for the Lackawanna and Erie-Lackawanna Railroads. Nonetheless, O gauge makers produce cranes in various schemes, from merely bearing a road's logo to showing its entire color scheme. Real cranes were either red or black. O gauge cranes go in whatever livery is desired, from the brilliant Chessie scheme to NYC jade to Pennsylvania tuscan.

The Orange and Blue CNJ Trainmaster: The Fairbanks-More Trainmaster Locomotive is popular among O gaugers, and one of the most favored schemes is an orange and blue version with CNJ lettering. Never mind that the CNJ never colored their FM diesels in tangerine / blue, not would they ever use so un-aesthetic a scheme. The classic CNJ Trainmaster for O is another of those things that has no real-life counterpart, but is an accepted norm within the hobby.

The S2 Turbine Steam Locomotive: the S2 turbine steamer was an experimental locomotive employed by the Pennsylvania Railroad. Only one was built. It generated awesome power and fuel-efficiency at speed, but ate fuel greedily and caused excessive wear when going slow. The experiment lasted but a few years, and then the S2 was scrapped as impractical. The faults outweighed the advantages. Nonetheless, the S2 is one of the most popular - perhaps the most popular - O Gauge big steam locomotive. Between 1947 and 1955, Lionel issued three O gauge and one O27 version of the S2. (The O27 was the same size as O, but had a different motor). Since then, it has resurfaced from time to time. In 2000, both Williams and MTH offer their versions. The S2 was a failure in the real world, but a tremendous success among O gaugers.

Auto Loaders: the two-level open Auto Loader car carriers are hot items with O gaugers. They were a nightmare for the railroads. The open carriers left cars exposed to elements and human mischief, thus almost assuring some damage before products were delivered. They were quickly replaced by Auto Boxcars and covered auto carriers. In O gauge, Auto Loaders remain popular. They sell like hotcakes whenever a new batch is made. Of course, Tinscale pikes don't have rock-throwing brats or flying debris, so the toy cars always arrive safely.

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