HO scale model trains are 1/87 the size of real trains and 1/2 the size of O scale model trains (HO stands for "half O"). As with O scale trains, the letter "O" in HO is a misnomer since the designation was initially conceived as a zero to identify trains that were smaller in scale than 1. But the use of the letter O rather than the numeral 0 crept into everyday speech among model-train buffs and remains the standard way to refer to HO scale today.

Though first invented in the 1930s, HO scale model trains didn’t become popular in the U.S. and Europe until the 1950s when the scale was heavily promoted by Märklin, Lionel, Athearn, and others. HO never quite gained acceptance in England, though, where larger 00 scale trains still predominate.

HO has two important benefits over trains of larger sizes. First, an HO scale layout of reasonably ambitious detail and complexity can fit on a table rather than requiring an entire room, as is the case with larger scales. Second, HO trains are less expensive to manufacture than OO, O, and other large-scale trains, which makes them more affordable to collectors and enthusiasts alike.

Most HO scale trains run on two-rail tracks using direct current (DC). Adjusting the voltage delivered to the tracks can increase or decrease the speed of the trains; reversing the polarity causes the trains to roll in reverse. Some manufacturers, notably Märklin, produce HO scale trains that operate on alternating current (AC), which is delivered to the train via a conductive third rail.

The gauge used by the majority of HO scale model trains is a standard HO gauge track that’s roughly proportional to the size of the trains running on top of it. But as with the OO scale trains in England that run on HO gauge tracks, HO scale trains are also made to run on a variety of different gauge tracks, which themselves are scaled-down versions of historical railroad track sizes.

Of these variants, the most common is called HOn3. This code denotes an HO scale train running on a track similar to the 3-foot, narrow gauge tracks used by Rocky Mountain railroad operators in the late 19th century.

One of the most enjoyable aspects of HO for collectors is the opportunity to join a local module club. Members of such clubs build modules of predetermined size; each module has a finite length of track. When members get together at model train exhibitions or in private homes, the modules are linked up and trains are run on the resulting massive layout, which often feels like more than just the sum of its parts.


Best of the Web (“Hall of Fame”)

HOseeker.net

HOseeker.net

This site is a treasure trove of HO scale model railroad manufacturer catalogs and other reference information, inv… [read review or visit site]

Airfix Model Railways

Airfix Model Railways

Dave McCarthy's Airfix Model Railway treasure trove is an in-depth archive of the company's plastic railway kits fr… [read review or visit site]

Gateway NMRA

Gateway NMRA

This great reference site for model railroaders, from the Gateway (St. Louis) division of the NMRA (National Model … [read review or visit site]

Postwar Lionel Trains Library

Postwar Lionel Trains Library

Bernie Schulz’s Lionel Trains Library focuses exclusively on postwar Lionel trains and accessories. The site cont… [read review or visit site]

Eric's Trains

Eric's Trains

Eric Siegel's site displays his collection of O-gauge/O-scale trains, tracks, turntables, and other accessories. A … [read review or visit site]

Tech Model Railroad Club of MIT

Tech Model Railroad Club of MIT

MIT's model railroad club, as one might expect, has one of the best websites for learning about how people play wit… [read review or visit site]



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Recent News: HO Scale Model Trains

Source: Google News

Community Notes: March 6, 2015
Daily Astorian, March 6th

Detachment 1228 Marine Corps League — noon, Uptown Cafe, 1639 S.E. Ensign Lane, Warrenton. For information, contact Lou Neubecker at 503-717-0153. Columbia Northwestern Model Railroading Club — 1 p.m., in Hammond. Group runs trains on ...Read more

Quick News
The Herald-News, March 4th

The Will County Model Railroad Association is an HO scale modular club of a new and experienced modelers working together to get more enjoyment from the hobby. For information, contact Chris Herzog at 815-263-3764 or chris.herzog@gmail.com or ...Read more

Weekend picks: Comedian Damien Lemon hits Zanies
Chicago Daily Herald, March 3rd

See an HO scale permanent operating model railroad at the Lake County Model Railroad Club's Spring Open House at 107 S. Main St. (rear entrance), Wauconda. The railroad ... Train enthusiasts can tour five buildings and outdoor grounds featuring...Read more

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

"We've graduated from Thomas to O scale, and now we're into HO. We're running the gamut." He's now a relatively new member of the Tri-County N Scale Model Train Club, which manned a huge display of the small-scale trains (1 inch to every 160 inches in ...Read more

Rails in the Garden: 16-stop tour is free
Arizona Daily Star, February 28th

Barry, a Lionel train fan as a child, was heavy into HO-scale model trains when he discovered the Tucson Garden Railway Society. “It's a lot more family oriented,” he says, compared to other clubs. The Blackwells had a clean slate when they started...Read more

Model railroad to mark anniversary
SaukValley.com, February 27th

The HO-scale model railroad will be featured from 10 a.m. to 4 p.m. March 7 and 8 at 1055 W. Beach St. The club house is the large, tan building behind the Canadian National Yard office on Fever River Place. Admission is $4 for adults, $1 for children...Read more

Scale Rails annual model train show Saturday and Sunday
Fort Myers Beach Observer, February 24th

Scale Rails of Southwest Florida, the biggest model train club in Southwest Florida, will hold its annual show Saturday and Sunday from 10 a.m. to 4 p.m. at the Araba Shine Temple, 2010 Hanson St., Fort Myers. There will be more than 95 tables of...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. ... "We had to take it slow, but that was our longest train we ever ran," Roger said...Read more