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

Unveiled> Two Museums in North Adams
The Architect's Newspaper, February 3rd

Nearby, The Extreme Model Railroad Museum will be a 700-foot-long addition to two historic freight train depots, with a total area of 32,400 square feet. In the museum, O scale model trains (1:48) will move through architectural dioramas created by the...Read more

Somerset 4-H Trainmasters to hold annual Winter Train Show
MyCentralJersey.com, January 26th

Proceeds from the annual winter train show support the Somerset County 4-H Trainmasters' College Fund and other club activities. Each year, the Somerset County 4-H Trainmasters Club awards a $1,000 scholarship to a graduating Senior who is a member ...Read more

The J611 steams again at the Ratcliffe Transportation Museum
Roanoke Times, January 20th

The most famous locomotive of that class, engine 611, and her sister engine 603, are now featured on the Brockmeyer O-scale layout at the Raymond F. Ratcliffe Memorial Transportation Museum. The 1/48 scale models represent a family of 14 Class J ...Read more

What's happening in Annapolis, Baltimore, DC, Eastern Shore and in Ocean City
CapitalGazette.com, January 14th

Baltimore Society of Model Engineers, 225 W. Saratoga St. 410-837-2763 or modelengineers.com. Operating Model Train Display: Two model railroad empires occupying 2,500 sq. ft., operating trains and trolleys in HO & O scale. Free. Now through Jan. 31...Read more

Model railroading caters to the child in all of us
The Wyoming County Examiner, January 13th

Rudolf said most of their work is done with HO scale trains, although they also have a couple of O scale models as well. EMMRRC has its headquarters over a residential garage owned by DePaola, who said he is in the process of converting one of his ...Read more

Hampstead business showcases free train garden
Carroll County Times, December 7th

O-scale model trains are 1:48 scale, meaning one scale-inch on the model train represents the equivalent of 48 inches on the real, life-size train. Linda Standiford, one of Roof Right's managers, said many of the company's employees are fairly young...Read more

Model Railroad tour takes train enthusiasts for a ride
St. George Daily Spectrum, November 11th

Just one of 12 model railroad systems that will be open to the public this weekend during the Color Country Model Railroad tour, Schneider's G-scale, or Garden-scale outdoor trains, chug along through a miniature world he has created in the backyard of...Read more

Hop aboard the Halloween train
The San Diego Union-Tribune, October 30th

Eight years ago she bought him an O-scale train set with a Halloween theme because she wanted a fun, not-too-scary, way to entertain young trick-or-treaters. The train was such a hit, they decided to build on their success each year. The layout is...Read more