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

Model train museum brings out the kid in everyone
Akron Beacon Journal, October 2nd

The museum, with its impressive, 15-by-30-foot operating layout, draws in children and adults alike with O-scale trains zipping through a multilevel display of villages, across rolling farmland and through tunnels all built in miniature form. Even the...Read more

Model-train show scheduled for Nov. 1 in Mont Alto
Herald-Mail Media, September 29th

The club is planning for more than 100 vendor tables with N-, HO- and O-scale model trains, as well as parts. A model-train display will be featured. The show also will include door prizes and food. Admission is $3 per person or $5 for a family with...Read more

Having a little fun with trains
Temple Daily Telegram, September 20th

There were more model trains, tracks and accessories than a person could keep up with Saturday during the Temple Model Train Show at the Frank W. Mayborn Civic and Convention Center. Sponsored by Central Texas Area Model Railroaders, the two-day show...Read more

All aboard! Old Fort will celebrate Railroad Day on Saturday
McDowell News, September 17th

On Saturday, Railroad Day will celebrate Old Fort's heritage of trains, trestles and tunnels. The event will be held at both the Old Fort Depot and the Mountain Gateway Museum. This photo from a previous Railroad Day shows the O-scale layout by the...Read more

Train enthusiasts on track for annual model train show
Temple Daily Telegram, September 15th

The depot is abuzz with activity as members of the railroaders club gather to prepare to welcome as many as 3,000 model train enthusiasts from across the nation to its 33rd annual Temple Model Train Show Sept. 19 and 20 at the Frank W. Mayborn Civic...Read more

Microsoft Azure selected to handle leading game developer's surging customer ...
WinBeta, September 14th

his studio have seen switching to Microsoft's Azure to scale its online traffic. Recently Jump Start experienced a surge of online traffic after a strategic alliance with DreamWorks Animation boosted demand for a multiplatform game based on the How...Read more

Collectors roll out model trains to draw strong crowds at Clayton show (VIDEO)
WatertownDailyTimes.com, September 13th

Children particularly enjoy watching his “O” scale trains, Mr. Jones said, because they're larger and easier to see than other models. On Sunday, three trains were featured on his electronic track. Two of them — emitting steam from chimney stacks...Read more

Marion man a finalist in Lionel train competition
McDowell News, June 20th

As part of its 115th anniversary celebration this year, Lionel, LLC, the iconic electric toy train company, will unveil a brand new boxcar featuring an original design. And this O-scale boxcar could feature the winning design created and submitted by a...Read more