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

Getting Out
Ellwood City Ledger, July 29th

Featured will be G scale, O scale and HO scale operating layouts and train-related vendors. A large rail memorabilia auction will begin at 6 p.m. Proceeds benefit the West Pittsburg station restoration project. Interested vendors or information: www...Read more

Dismantling of railroad bridge in Monroe attracts interest
Monroe Evening News, July 28th

The 73-year-old Monroe-area resident said he has been fascinated with trains since he was a child. An O-scale train collector, Mr. Vancena loves to construct models as well. He looked fondly at the bridge over the River Raisin as crews from Ruhlin Co...Read more

Lionel train collectors engineer grand display in Danvers
The Salem News, July 22nd

Passionate customers included Bob Freeman of Beverly, who belongs to the Boston Metro Hi-Railers, a group whose clubhouse in Wilmington features yards and yards of track and trains the same size, if not always the same brand as Lionel's 'O' scale...Read more

Historic Model Train Ejected From Union Station Has New Home: White Fence Farm
Westword, July 22nd

When the crowds disembarked at Union Station a year ago this Saturday for the gala reopening, they saw a stunning transformation of the century-old terminal, now a grand public space full of bars, restaurants, lounging areas and, overhead, the Crawford ...Read more

Delmar couple hopes to find train lover to buy their house
Albany Times Union, July 14th

Bethlehem. A five-bedroom, 3,300-square-foot Delmar home on sale for $600,000 boasts hardwood floors, a spiral staircase, central air conditioning, a three-car garage and a $180,000 model train collection. OK, that detail about the trains doesn't...Read more

Spring Creek Model Trains thrives in rural Nebraska
Lincoln Journal Star, June 27th

When he was 10 years old, he received his first model trains as a Christmas gift, an HO scale set produced by Tyco Toys. HO is half of the O scale, a larger-sized railroad scale popular until the early 1960s. Today the HO scale makes up 75 percent of...Read more

Crosslake model train museum displays new exhibits and layouts
Northland Press, May 25th

The members of the museum have also been busy this winter and spring building new layouts and scenery on the O Scale and HO Scale model train layouts. The O Scale now features a coal processing plant, and the Saint Paul Union Depot model has been ...Read more

Model train show rides into Augusta Expo
Staunton News Leader, May 3rd

Seeing them smile ... it makes me happy." There are four different scales for model trains — G scale, which is a 1:22 proportion/scale; O scale, which is 1:48; HO scale, which is half of the O scale at 1:87; and N scale, the smallest size at 1:160...Read more