Atlas HO Code 100 #8 Mark IV Turnout – Left – ATL285

Atlas HO Code 100 #8 Mark IV Turnout – Left – ATL285 is a broad-geometry left-hand turnout designed for HO scale model railroaders building realistic mainlines, passing sidings, crossovers and other track arrangements where smoother routing through a switch is desired. This #8 turnout provides considerably broader geometry than lower-number turnouts, making it particularly useful for mainline trackwork and layouts operating longer locomotives and rolling stock.

Designed for the Atlas HO Code 100 track system, the turnout features solid nickel silver Code 100 rail with black injection-molded plastic ties and connects with compatible Atlas Code 100 track.

What Does #8 Turnout Mean?

The #8 designation describes the turnout's frog geometry. In simplified terms, a #8 frog spreads approximately one unit sideways for every eight units traveled forward through the frog area. A higher turnout number therefore creates a shallower divergence and generally requires more length than a lower-number turnout.

This broad geometry is why #8 turnouts are especially useful for mainline switches, passing sidings and crossovers. Equipment follows a more gradual route through the diverging track than it would through a tighter #4 or #6 turnout.

Left-Hand Turnout

ATL285 is a left-hand turnout. When approaching the turnout from the single-track or point end, the straight route continues forward while the diverging route branches toward the left.

The left-hand designation describes the direction of the diverging route and is important when planning yards, sidings, crossovers and junctions. Right-hand turnouts are used when the desired diverging route needs to branch in the opposite direction.

Why Choose a #8 Turnout?

A #8 turnout takes more layout space than a tighter turnout, but its broader geometry can provide several advantages where space permits. The more gradual diverging route creates a smoother-looking transition and is particularly appropriate for areas intended to represent higher-speed or heavily traveled railroad track.

#8 turnouts can be especially useful when operating long passenger cars, modern freight cars and larger locomotives. Equipment requirements vary, however, so turnout selection should always be considered alongside the minimum-radius and trackwork recommendations for the models being operated.

Common Uses for a #8 Left Turnout

• Mainline switches and junctions
• Passing sidings
• Mainline crossovers
• Double-track railroad arrangements
• Arrival and departure tracks
• Broad industrial leads
• Passenger terminal approaches
• Locations operating longer locomotives and rolling stock

Atlas HO Code 100 #8 Mark IV Left Turnout Features

• HO Scale model railroad turnout
• #8 turnout geometry
• Left-hand configuration
• Mark IV design
• Broad diverging geometry
• Suitable for mainline, siding and crossover applications
• Code 100 rail profile
• Solid nickel silver rail
• Black injection-molded plastic ties
• Designed for Atlas HO Code 100 track systems
• Connects with compatible Atlas HO Code 100 track
• Atlas manufacturer item number 0285
• Fusion Scale Hobbies SKU ATL285

#8 vs. Tighter HO Scale Turnouts

The appropriate turnout number depends on available layout space and the type of railroad being modeled. Lower-number turnouts change direction more quickly and can be useful where space is limited, such as compact yards and industrial switching areas.

A #8 turnout provides a considerably more gradual diverging route. Where sufficient space is available, this makes it an excellent choice for visible mainline trackwork, broad crossovers and other locations where smoother geometry is a priority.

Manual or Powered Operation

The turnout points must be positioned to select either the straight or diverging route. Depending on your layout design and operating preferences, Atlas turnouts can be incorporated into trackwork using an appropriate manual or powered turnout-control arrangement.

Browse our Atlas HO Switch Machines collection for compatible turnout-control components and additional options for operating Atlas HO track switches.

Build with Atlas HO Code 100 Turnouts

Browse our complete Atlas HO Code 100 Turnouts & Switches collection for additional turnout sizes and configurations for mainlines, yards, sidings and industrial trackwork.

Combine this turnout with products from our Atlas HO Code 100 Track collection to build a complete HO scale track system.

Complete Your Trackwork

Use Atlas HO Code 100 Straight Track and Atlas HO Code 100 Flex Track to continue the routes beyond the turnout, or browse Atlas HO Code 100 Crossings for track plans where two independent routes intersect.

For rail joiners, terminal connections, track nails and other installation components, browse Atlas HO Track Accessories.

Atlas Code 100 track can also be installed over Atlas HO Cork Roadbed to provide a raised track profile and foundation for ballast and finished scenery.

Shop HO Scale Model Railroad Track

Explore our complete Atlas HO Scale Track selection or browse Model Railroad Track for additional track systems, turnouts and layout-building components.

Shop additional products from Atlas Model Railroad and browse Atlas In-Stock Products.