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

Fiddlers Grove Train Museum starts Model Train Club
Lebanon Democrat, April 27th

This will be an all-scale model railroad club. Currently, the Fiddlers Grove Train Museum has an extensive “O” gauge layout and a small “H O” scale layout with plans to expand the “HO” track. The club will be open to anyone interested in model train...Read more

Clubs briefs Journal April 27
Casper Journal, April 26th

The members of the Central Wyoming Model Railroad Association have been saddened by the departure to his Eternal Rest of one of our charter members, Bob Baden. He was Wyoming's first NMRA master model railroader, and for many years, the only one in the...Read more

Model train tours to make stops in Ligonier, Latrobe, Greensburg
Tribune-Review, April 25th

It includes hand-held remote devices that synchronize train movement with the sounds of chugging engines and screeching brakes and puffs of simulated smoke and diesel exhaust. Most of Sheats' train sets are at “O” scale, in which 1 inch equals 4 feet...Read more

Town Crier: Clubs
Casper Star-Tribune Online, April 23rd

We are planning on working on the 100+ year-old baggage cart and getting it refurbished with new wood. And we will be working on Bob's 'O' Scale layout to make it more user friendly and bring it into use more frequently. We welcome any assistance that...Read more

Clubs briefs
Casper Journal, April 14th

The members of the Central Wyoming Model Railroad Association have been saddened by the departure to his Eternal Rest of one of our charter members, Bob Baden. He was Wyoming's first NMRA master model railroader, and for many years the only one in the...Read more

Model railroaders hope new St. Paul site gets hobby back on track
Minnesota Public Radio News, April 11th

The exhibit had to be cut into movable pieces. The O-Scale Exhibit, which is the centerpiece at Twin City Model Railroad Museum, is a display depicting the influence of the railroad on Minneapolis and St. Paul from the 1870s through the 1950s. Tom...Read more

Railroad watching at Business After Hours
Oskaloosa Herald, April 10th

OSKALOOSA – Penn Central Model Railroad Inc. is proud to host the next Business After Hours Thursday, April 14 from 4:30-6:30 p.m. at their showroom in Penn Central Mall. Come see train layouts featuring N, HO and O scale trains carrying several ...Read more

Saluda Grade train model donated to Saluda Historic Depot
Tryon Daily Bulletin, March 31st

Just like building a railroad up a steep grade, Dr. McConnel was challenged building a train model of the Saluda Grade because of the space limitations in the depot building. Instead of drawing the O scale model to scale in width, he would go up and...Read more