O scale refers to a model railroad train that is 1/48th the size of a real train—in the U.K., O scale trains are generally 1/43rd the size of the real thing while in Europe they are 1/45th as big. Like a real train, O scale model railroad trains run on two-rail tracks. The gauge of those tracks is O, which describes tracks whose rails are 1 ¼ inches apart. Even though O scale model trains frequently run on O gauge tracks, strictly speaking, the two Os have nothing to do with each other.

The letter "O" is actually a misnomer since the designation was initially conceived to identify trains that were smaller in scale than 1, which had been the standard. Since the only number smaller than 1 is 0, that’s how early O scale trains and O gauge tracks were identified. Similarly, HO was originally intended to describe a scale and gauge that is half (H) of zero, but the letter O (pronounced “owe”) crept into everyday use among model train buffs and has remained the way to refer to zero ever since.

Confused? A lot of people are. But for those who are first and foremost focused on O scale, nothing else matters. For these enthusiasts, replicating the detail of a full-scale train in an equally detailed layout is the only goal.

An O scale model train’s tracks, as it turns out, are a key part of creating a sense of realism. When an O scale train is run on three-rail O gauge tracks (the middle rail delivers the power to the locomotive) such as those made by Lionel, the train rides higher off the surface than it would in real life, thus shattering the illusion. Model railroaders who run O scale trains on three-rail tracks are known as hi-railers. It’s not quite a put down, but it isn't really a compliment, either.

Toy manufacturers in the early part of the 20th century originally embraced the O scale so they could offer customers model trains that took up less space than their standard-sized counterparts. Because they were smaller, these trains were also less expensive. At one time or another, Märklin, Lionel, MTH, Williams, Atlas, and Weaver, among others, all offered O scale trains. Fans of brass model trains are also frequently O scale acolytes because the earliest, most collectible brass trains made in postwar Japan were usually O scale.

The smaller scale took off in the 1930s, when affordability trumped most other concerns thanks to the Depression. The scale also benefited from its adoption by industry leader Lionel, which sold two O gauges for its O scale trains. Lionel’s regular O gauge track was the same width as its O-27 gauge track (1 ¼ inch), but the O-27 had a lower profile than regular O, and its thinner rails allowed all but the longest O scale model trains to make tighter turns (a circle of O-27 tracks has a diameter of 27 inches instead of 31).

Today, neither appeal to O scale purists who put accuracy and authenticity above mere convenience. There is even a vocal contingent of two-rail O scale enthusiasts who advocate for the conversion of model trains designed to run on three-rail tracks to model trains that will run on just two. This often requires changing a train’s trucks (the framework for the axles and wheels) as well as a layout’s wiring (from AC to DC), but the lower profile that results makes an O scale model train look a lot less like a toy and more like the real thing.

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Recent News: O Scale Model Trains

Source: Google News

TALK OF THE TOWN: Q&A with Larry Bailey
Bowling Green Daily News, April 13th

From “O” scale to “Full” scale. When the opportunity came to actually work on a full-scale train at the BG depot, the kid in me jumped at the chance. Initially I got involved to memorialize on video the arrival of the caboose, diner, sleeper and...Read more

Model trains a fun hobby
The Garden City Telegram, March 22nd

Brad Nading/TelegramDavid Demers, 4, Hugoton, tries his hand at running a Thomas the Tank Engine “O”-scale train with a remote control Saturday at one of the displays during the Garden City Train Show in the Finney County Fairgrounds exhibition ...Read more

All aboard for April train show
Algona Upper Des Moines, March 12th

ALGONA — Arlen Benschoter's massive 'O' scale Lionel train display at the Kossuth County Agriculture and Motorsports Museum will be the feature of a model train show on Saturday, April 18, sponsored by the Prairie Lakes Division of the National Model ...Read more

Railroad Days to be hosted, appropriately enough, at Allen Train Depot
Star Local Media, March 11th

Local Allen resident Stan Schwartz is an active Dallas-Fort Worth O Scale Club member and is organizing the Allen exhibit. Schwartz has been collecting model trains for over 60 years. In 1952, he bought his first Model Railroader magazine and continues ...Read more

Are model trains still relevant? Hobbyists stay on track at the Great Train ...
OregonLive.com, January 24th

What followed was a lifelong fascination with trains and model railroads, leading Bartko through decades of technological innovations, finally bringing him front and center at the Rose City Garden Railway Society's massive display at the Great Train...Read more

The Trains of Christmas Display Hits 25th Anniversary
WHAG, November 29th

HAGERSTOWN, Md - The Hagerstown Roundhouse Museum (HRM) celebrated its 25th anniversary Saturday with sounds and smells of Christmas past and present with an "O" scale toy train track as part of the Trains of Christmas display. The toy train ...Read more

Model trains by the mile on view at this exhibit
NJ.com, November 18th

Members of the 80-year-old society operate a train museum and two large "railroad empires" that include model train layouts that cover almost 4,000 square feet. The larger "O" Scale layout is 40 by 70 feet and has almost 20 scale miles of train track...Read more

Massive model train club in Paterson invites Halloween visitors (PHOTOS)
The Star-Ledger, October 24th

The NJ HiRailers claim to have the largest "O-scale" layout in the country, at 185 feet by 40 feet. O-gauge refers to the scale of the layout, which is 1:48. Hunterdon County's Northlandz, which claims to be the largest model layout in the world, is HO...Read more