What makes shows possible is that the units that individuals build will connect and interoperate once people arrive at the show. There are standards in every gauge and for some gauges there are multiple standards. The concept has been around for a long time, with the NMRA developing the first set of model railroad standards starting in 1935. Those standards covered the very basics including track, couplers, wheels, clearances, electrical and more as time passed on. Even today, the NMRA continues to refine, update, and expand their standards. DCC is an example of a relatively recent effort that allows for interoperability of DCC decoders and control systems.
N Scale has a number of module standards, starting with the original specifications dating from 1973 that popularized modular railroading and N Scale. The NTRAK standard was certainly the most popular standard at one time. In 2000, the caretakers of the NTRAK standard started publicizing a new standard called T-TRAK which had its roots in Japan. Today we believe that T-TRAK is the most popular of all modular standards with thousands of units built or being built. Details of both of these standards are available at NTRAK.org.
One off-shoot of NTRAK is the branch-line module specification call oNeTRAK. Not as popular as NTRAK, there are clubs that have developed entire layouts or at least loops of oNeTRAK modules that connect to NTRAK loops. The junction module has helped to make the connection much easier and convenient.
BendTrack is a spin-off created in 1986 that uses balloon modules to turn the double track around to the opposite side of the module. While NTRAK (and oNeTRAK) specify 40” height from ground to the top of rail, the BendTrack specification is a 50” height but many of specifications for BendTrack are the same as those for NTRAK
ModuTRAK is a Chicago area group of modelers who have developed their own standard and built some very detailed and prototypically oriented modules. The specifications call for double track, code 55, run flush to the end of the module, requiring very accurate placement, but immensely simplifying setup. Module design emphasizes lightweight construction. Track spacing is 1.25 inches (center to center).
Finally, the third most popular standard and newest is Free-moN. This standard was created by Wesley Steiner in 2002 who continues to control the standard and the concept. Like ModuTRAK, this standard also specifies code 55 track, with a single track down the middle of the module, running to the end of the module. Free form modules encourage point-to-point layouts, with a minimum 22” radius and #6 turnouts.
Each of these standards has its advantages and disadvantages. For example, not having backdrops makes photography a challenge along with maintaining the illusion of the magical model railroad world. Height can be a hot topic, with T-TRAK at child’s eye level very enticing to youngsters while the hard-core model railroader prefers the 50” height to foster the concept of railfanning as the train passes through the modules. Requiring DCC simplifies wiring and electronics such as signaling and detection but can disenfranchise the beginning model railroader or long time modeler who wants to run older equipment that does not readily lend itself to conversion.
Regardless of which standard is your favorite, NTRAK.org will continue to promote all N scale module railroading. Comments and observations are always welcomed and can be directed to firstname.lastname@example.org.