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

Calendar of Events
The Phoenix, December 18th

Annual Model Railroad Open House: Held annually since 1975, Schuylkill Valley Model Railroad Club's open house is “fun for kids of all ages.” See and hear freight and passenger trains pulled by steam or diesel engines over 700' of track. Four different...Read more

Holiday train display draws crowds in Westernport
Keyser Mineral Daily News Tribune, December 16th

(Tribune photo by Richard Kerns)Josh Leatherman watches the HO-gague model trains with his son Camden, Sunday afternoon in Westernport. The pair visited the Western Allegany Model ... “We've upgraded big-time,” Greene said. The layout is located in the...Read more

Model railroad trains on display in Downers Grove through Dec. 28
Suburban Life Publications, December 15th

DOWNERS GROVE – BSA Venture Crew 57 model railroad club is inviting residents to view its display of running HO scale trains. Hours are 10 a.m. to 5 p.m. Saturday and 11 a.m. to 4 p.m. Sunday, at 5122 Main St. The display will be available for viewing ...Read more

Pardon me boys, is that the Highlands County choo choo?
Highlands Today, December 14th

The model railroad club ran 40 trains over five HO scale-miles of tracks Friday through Sunday in a store north of Kmart. Tracks ... Interestingly, one of the biggest attractions is the smallest, the 1:220-scale Air Train, designed and constructed by...Read more

Old train stations on display during show in Torrington
Torrington Register Citizen, December 14th

The 14th annual train show was presented by local model train club Torrington Area Model Railroaders, who exhibited two modular layouts – one in HO-scale (which measures a railroad set engine at 1.97 inches), the other in G-scale, which is the largest ...Read more

Model train show set for this weekend at Torrington Armory
Torrington Register Citizen, December 10th

The Torrington Area Model Railroaders, based on Lewis Street, will present two layouts – one in HO scale and one in G scale. Valley N-Trak, a group whose members come throughout the region, will have its N scale layout on display, organizers said in a ...Read more

A guide to Lehigh Valley holiday model trains
Allentown Morning Call, December 5th

The second floor's 800-square-foot display features HO scale trains, which are the most popular in the country. Viohl says HO trains are designed to re-create actual railroads. The displays feature a loaded coal train stretching to more than 100 cars...Read more

Model Train Day
Morning Times, November 30th

The Sayre Historical Society hosted a special “Model Train Day” event at the museum on South Lehigh Avenue Saturday. The event featured model trains in all shapes and sizes, including two HO-scale layouts, a large antique toy train, Lehigh Valley...Read more