Discussion in 'HO Scale Model Trains' started by thaddeusthudpucker, Nov 28, 2007.

  1. thaddeusthudpucker

    thaddeusthudpucker New Member

    I am sure they are out there somewhere, but dies anybody have a good set of standards that I could use for building an HO modular layout? What is the most popular style/configuration?

    thanks in advance!
  2. PWRR-2207

    PWRR-2207 Rogue Islander


    To me, Modular Designs seem to fall into three groups:

    NMRA Standards
    Free-Mo Standards (based on NMRA)
    Club Standard (usually based on NMRA or Free-Mo)

    Some links:

    NMRA (Scroll down to modular section. Can be overwhelmingly technical)

    Free-Mo (Can also download as an Adobe Acrobat document. Written in plain English with lots of diagrams.)

    Clubs/Resources - some websites with their standards made available that I found easy to understand and helpful:
    (our own "Modular Railroading Resources" sticky in the "Modular Layout Forum" (where I am betting this post gets moved...)
    North Georgia Modurail
    Club Files
    East Penn Traction Club - Module Standards

    I am sure there are plenty more clubs that people here can point you to...
  3. MasonJar

    MasonJar It's not rocket surgery

    There's a whole bunch more in our Modular Layout forum.

    My local modular club uses standards based on both freemo (single main, centred in the module) and "traditional" or "standard" based on NMRA (double main along one side). See and look for the Standards link.

    The other question I have is do you intend to make your layout truly modular, or do you just want to be able to take it apart easily once or twice (e.g. when you move)?

  4. 60103

    60103 Pooh Bah

    You need to decide between modular, sectional, and portable.
    A modular layout will have standard interfaces (usually ends) and the sections will be a standard length.
    It will be designed to fit with other modules. You should probably check out which modular groups are local and what standards they use.
    You can build a home layout that is modular, but it often is a compromise on scenic and track planning flexibility.
    A sectional layout need not have ends that meet all the standards. Track spacing and location will not be fixed and track can meet the edge at other than a right angle. You will not be able to mix the sections around the layout.
    A portable layout may sacrifice even more standardization. It may just have the benchwork such that it will come apart when you move.
    Another reference point is the Cat Mountain and Santa Fe Railroad that uses Domino sections.
  5. Russ Bellinis

    Russ Bellinis Active Member

    If you are looking to build a home layout, sectional or portable is probably preferable to modular since you won't be changing things around much so you don't need the interchangeability.

    If you are interrested in building a module in order to use it at a modular club meet, you should probably check with a local modular club. The ho modular club I joined was in existance as a modular club before the advent of n-trak, and way before the NMRA set modular standards. In fact the NMRA asked for copies of our club standards before adopting standards for modular clubs. NMRA modules will work with our club modules, but they would need special joiner tracks because we use a 2 inch set back that requires a 4 inch joiner track while NMRA uses a 4.5 inch set back to use a standard Atlas 9 inch sectional track for a joiner. Therefore a module built to NMRA standards needs a 6.5 inch joiner track to mate up with our set up. We use 4 inch joiner tracks for 2 reasons.

    1. all but very small diesels and small steam engines will bridge a 4 inch joiner, picking up power on either side of the joiner track. Since all track sections have drop wires soldered to them, but joiner tracks rely on rail joiners to cqarry power, a locomotive that doesn't bridge the joiner track could stall on the joiner track if the rail joiners make a bad connection. With the 9 inch snap track joiner, a gp9 could stall out on the joiner if the rail joiners loosen up.

    #2 with a 2 inch set back we can put a 36 inch minimum radius on a 4 foot x 4 foot corner module with easments. The NMRA standard modules are locked in to a maximum of 30 inches on a 4 x 4.

    Finally, if there is no modular club in your area, but you would lie to build a module in order to hook up to other modules at a national or regional NMRA meet, then build the module to NMRA standards since that is as close to a universal standard as you will find.

    Here is a link to the home page for the Orange County Module Railroaders:
    Orange County Module Railroaders- So. California HO scale RR

    The following is a link to our module standards:
    OCMR Module Standards

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