Module Compliance Document
North Georgia Modurail
HO scale Modular Railroad Club
Module Compliance Check-Up
by Gary Bechdol
At the setup at the Greenburg Show on November 1-2, 2003, we encountered a significant number of operating
problems caused by modules no longer conforming to NGM and NMRA standards, most notably at the module interfaces. Most of the
problems appeared to be caused by the track at the ends of modules humping up due to loose track nails, ballast working under the
ties, or swollen roadbed. Not only was this frustrating for the operators, it is embarrassing to the club to have to continually stop to
rerail or recouple cars in front of the public. Every module, therefore, needs to be checked for compliance
with the published standards.
To begin this, lay a two foot (minimum) metal straight edge along the top of the rails, making sure that it extends to the
end plate. If you can slip a 0.020in piece of plastic under the straight edge at any point within the last 6 inches of track, the track should
be relaid. If this sounds extreme, remember that the adjoining module may also be off by 0.020in, which will total to 0.040in, or almost half
the depth of a standard Kadee coupler knuckle.
Remove the offending length of track using whatever method you prefer. Thoroughly scrape all ballast, glue, etc., from
the roadbed. This must be done; otherwise you will not completely solve the problem. After scrapping the roadbed, set a
piece of track on the cleaned section and recheck the vertical alignment with the straight edge. If there are no more gaps, you may
continue to the next step. Otherwise, you will need to sand the roadbed down until the track passes the straight edge test.
Unless you are working in your garage in midsummer, leave a small gap (0.010in-0.020in) between track sections to
provide for expansion/contraction. To ensure the proper offset from the end plate, set the blade of an adjustable carpenter's square to
1-1/2 inches. Place the square against the endplate with the blade in line with one rail, and move the track section until the rail just
touches the blade. Cut the replacement track to length.
Remove two crossties off each end of each section of track that is to be permanently joined. At the end of the section
that will meet the bridge tracks, cut off three ties, even if there is already a cutout to accommodate the rail joiner (Atlas track). This is to
ensure that there will be enough free rail length to slide a rail joiner completely onto the rail. Use a Dremel tool, rat tail file, or X-Acto
knife to remove enough material under the rail seat to clear the rail joiners. Too much is better than not enough.
Glue, do not nail, the track to the roadbed. Use a very thin layer of Liquid Nails for Projects
. You will have a very few minutes to adjust the track. Use the square to make sure the track section is truly perpendicular to
the end plate. Slide the modified ties under the ends of the rails before the glue dries, then weight the replaced track sections for at
least an hour. A piece of 3/4-inch plywood, 12 inches long or more will protect the track and help to keep everything in the same
plane.
For more thoughts on the subject go to Gary Green's
Trackwork Handbook. This website addresses issues with Free-Mo track construction, but many of the issues are the same for
NGM and NMRA standard modules.
This page last updated Fri Dec 19 10:49:44 2003
