The National Association of S Gaugers is a non-profit corporation that supports all "S" (1:64) modelers, manufacturers & vendors. It was formed at the 1960 NMRA Convention. Its goals include educating the model railroading community and the public at large about 1:64 modeling and how to accomplish that. The roots of S scale in the United States go back to the 1930s (much earlier in England). As with other scales at that time, modelers had to build everything from kits or scratch, but the last few decades have seen explosive growth in kits and RTR models available in die cast, resin, styrene, ABS, brass, and now 3D printing. The organization's publication, The Dispatch, and its extensive website help show modelers how to combine these resources into functional and realistic model railroads.
The NASG has served to push technical issues in 1:64 scale. There are two sets of engineering standards: NMRA/NASG standards which are very realistic (NMRA also defines Proto64), and hi-rail (called "deep-flange" by the NMRA) for those with a lot of American Flyer equipment that they want to keep operating without conversion. The NASG Standards Committee is currently preparing a draft of updated module standards for the scale, given the electronics advances since the 1980s.
The very active contingent of narrow gauge modelers tend to be extremely prototype-oriented regardless of whether they are in Sn3 (Colorado, California, Pennsylvania, etc), Sn2 (generally Maine railroads), or Sn42 (Newfoundland, logging and mining lines, and international railroads in New Zealand, Australia, South Africa, etc.).
NASG Coordinator
R James Whipple
president [at] nasg.org