Rails on Wheels
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Saline, MI 48176-1588

Founded 1988

Rails on Wheels Module Standards

Updated: 17-JAN-2010

New Module Standards and Recommended Practices Were Adopted in January 2010

Jeff Fryman's Branchton moduleWith the theft last fall of the club's trailer and display layout modules, we took the opportunity to review our module standards prior to rebuilding. In the process, we identified three key areas where we felt that we could improve the layouts going forward:

  • A more realistic mainline minimum radius -- layouts built with modules using our former 54" minimum required a footprint that was too large for some venues, often by only a foot or two.
  • Replacing our standard of running rails to the ends of the module interfaces with a method that would not expose the rails to ask much risk of being torn out during set-up and tear-down.
  • Reconfiguring the electrical connectors, built with Anderson PowerPoles, in such a way as to restore our ability to rotate a module end-for-end without having to use crossover wiring adapters.
  • Improving track alignment at the module interfaces through the use of a standardized end template we will produce and make available to members building modules.

These standards were developed to enable the construction of a series of HO scale modules which may be freely connected in any configuration with other modules conforming to these standards. These specifications have been chosen to allow for the reliable operation of the widest variety of HO scale standard gauge equipment from any era, including articulated steam locomotives, scale-length passenger cars and modern "hi-cube" auto parts cars.

As these standards are reviewed and changed periodically, the standards presented here should be considered current as of the date printed above, superseding all previous revisions.

While these are not identical to the National Model Railroad Association module standards and recommended practices, they represent a superset with sufficient compatibility to allow interface with modules constructed to NMRA standards and recommended practices. It is a simple matter to connect modules conforming to our standards to those built to NMRA specs, requiring only a section of filler rail and a simple wiring adapter.

These standards should serve as guidelines- for specific interpretations of the standards, it is preferable to contact a Rails on Wheels member.

The module standards we have previously used are available in Adobe Acrobat format (requires Acrobat version 5.0 or newer reader, available for free download from Adobe).

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