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

RI train expo offers something for everyone
Quad-Cities Online, March 1st

"As soon as he said, 'Choo-choo,' we started buying Thomas," Mr. Genung said of the popular children's train toys Sunday during the Great Train Expo at the QCCA Expo Center. "We've graduated from Thomas to O scale, and now we're into HO. We're ...Read more

ALL ABOARD! End of the line for state's biggest HO scale layout in downtown ...
The Daily Jeffersonian, February 13th

The Guernsey Valley Model Railroad club began 40 years ago. This weekend, after traveling thousands of miles, the H-O scale trains will reach the end of their line. The club modeled the layout after Southeastern Ohio, featuring Guernsey County as a...Read more

18th annual Rails in the Rockies this weekend
Estes Park Trail-Gazette, February 11th

Other displays include: American Flyer Interactive Layout; Colorado Wyoming LEGO@ User Group (CoWLUG) layout (this year with a surprise theme) a circus train exhibit; and, Slim Rails Layout from Colorado Springs. There will be multiple layouts in...Read more

Depot museum open this Saturday
State Gazette, February 4th

Carlton Willis places a grass mat on the new Lionel, O-scale, train board inside the Newbern Depot Museum. The new train board was constructed by City of Newbern employees and is approximately 16 feet long and 5 feet wide. The new train board stands at ...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

Fairbanks man builds elaborate model train layout
Kenai Peninsula Online, April 27th

In a friend's warehouse space, he's building a layout for large “O-scaletrains. It's probably the largest O-scale layout in the Interior, he said. O-scale is one of the largest scales for model trains. With a 1:48 scale, each inch in the model world...Read more