Please help support this website by becoming a TrainWeb Patron for just $5 per month. Click here for more info.

TrainWeb Reports & Web Sites: Featured Today Past Highlights Previously Featured Slideshows The Big Stories Directory



"Connecting the nation, one module at a time."

Home .:l:. About Us .:l:. About Free-mo .:l:. Contact Us .:l:. Links


Free-mo is the US version of the European Fremo style of modular model railroading. The difference between Free-mo and other modular layouts is that Free-mo uses a single track mainline as standard and layouts and modules are designed to be set up in a way that allows many opportunities for realistic operations. Free-mo is not like the standard modular layouts everyone is used to that usually has trains just running in circles. Realistic modeling and operations are the key objectives in Free-mo and the layout set-up can be configured in a point-to-point, point-to-loop, loop-to-loop, or any variation with multiple spur and branch lines originating from the main modules.

Free-mo modules are also constructed with lots of detail in mind. Everything is modeled as realistically as possible. Some modelers will model certain eras, places and railroads as close as possible. Others may freelance their modules, but model the equipment similar to the prototype.

Modules usually consist of a frame using 3/4" strips of high grade plywood and a 2" pink or blue foam board top. There are many different ways to construct a module, as long as they all join together with minimal adjustments. With Free-mo, you are not limited to a 2'x4' module. You can design and build your module, or module set, in just about any way you choose to make modeling your region easier and the way you want. The main standard is that your module must be at 50" to the top of the mainline rails and your mating ends must be 24"x6" for single track, 26"x6" for double track mainline.

The following are general standards from the Free-mo website in 2003. Please visit the site for current standards.


Module ends shall be 1x6 (3/4” birch plywood works well) or equivalent to provide C-clamping to adjacent modules. Single Track ends are to be 24” wide, double track ends are to be 26” wide, mini-mo ends are to be no smaller than 8” wide. For mini-mo, however, a 12” end width is preferred. Roadbed to be ¼” cork or equivalent on ½” plywood or equivalent (foam tops are acceptable), braced to prevent sag or flexing. The module (set) shall have at least four legs and stand alone; this does not apply to mini-mo. Mini-mo’s must have legs for adjustment but not need to stand alone. Nominal and minimum height of railhead from the floor is 50”. Maximum height of rail is to be 62”. On modules with grades, the elevation of the high end shall be some multiple of ¾” above the low end. Legs shall have adjustment of plus or minus 1”. The bottoms of the legs shall have rubber tip or equivalent floor protection. Mainline maximum grade is 2.0 percent (1/4” per foot) with the track level for 6” from each end. Vertical curves shall be appropriate for mainline operation of contemporary long cars. Modules may be used with spectators on either side. No backdrops are used with Free-mo modules.


Track shall be code 83 nickel silver on the mainline, allowance for code 70 on the through route for modules specifically designated as branch line only. Modules may use flex or hand laid. Minimum radius is 42” (preference to 48” for minimum radii, modules built with 36” radius curves will be used but usually limited to branch line service, this is now official) with at least 12” of straight track between reverse curves. Spacing between tracks on curves should allow for long cars to operate without fouling each other. Observe NMRA Recommended Practices for curved track spacing. Mainline Turnouts shall be at least #6. At the ends of the single track module, the track shall be centered on the 24” width, double track modules shall have the first track located 12” from a side on the 26” wide end, and the second track 12” from the opposite side allowing 2” between the two tracks. Track must be perpendicular to the end, also straight and level for 6” from each end of the module. Rail shall be cut off 1” away from module end; ties and ballast shall be continued to the module end for good appearance and matching with the adjacent module. Free-mo printed circuit board tie plates are recommended for ends.


Turnouts shall not rely on points to power frog. Wire shall be #18 or larger stranded. Feeder wire can be of 24 gauge or heavier. There shall be a 4 or more position barrier strip at each end under the module for wire hook up.

Wiring consists of 4 separate bus wires and 6 conductor DCC Digitrax Loconet bus. All ends have a pair of male and female 2 pin Jones plug (Part # P-302-CCT and S-302-CCT) for the mainline, a single 2 pin trailer plug (Radio Shack Part # 270-026) for the accessory power, and a surface mount 6 conductor RJ12 box mounted to inside of module 1x6 end.

Mainline wiring is as follows for Jones plugs (must be facing module end for correct perspective):
• Single Track – Male pin 2 right rail, male pin 1 left rail. Female pin 2 left rail, female pin 1 right rail. The same wiring situation would be found for the other ends.
• Double Track – Male pin 2 right rail, right track, male pin 1 left rail, right track. Female pin 2 left rail, left track, female pin 1 right rail, right track. The same wiring situation would be found for the other ends.

Accessory power is wired straight through. A bridge rectifier and filtering capacitor, may be used to convert AC or DCC signal to DC. Applications that require AC or DCC signal may utilize power directly from the bus.

Each module needs a RJ12 Loconet connection point, one every end, mounted on the inside of the module, and one dual flush mount 6 conductor RJ12 faceplate mounted on each exposed side of module, for throttles.

All of the Loconet connectors and associated cables need to be connected together straight through (i.e. pin 1 – pin 1, pin 2 – pin 2, pin 3 – pin 3, etc. Note: Standard telephone cables are not wired straight through).

To connect the DCC bus between modules, a 2 foot RJ12 to RJ12 cable is utilized.

To connect a DCC booster to a module, a 4 foot RJ12 to RJ12 cable is utilized. A 4 foot cable with one female and one male 2 pin Jones plug on one end, plugged between interfacing modules, connected to the output of the booster.


Digitrax, and/or other Loconet compliant DCC and accessories are standard for interoperability among free-mo clubs. For more information about technical specifics consult Digitrax website.


General module fascia color shall complement scenery and not draw attention from the scene. Mainline shall be ballasted Woodland Scenic's fine light gray or equivalent, and some form of scenery hiding the bench work. Standard mainline rail color is Floquil/Polly-S Roof Brown or equivalent. Scenery at the Free-mo standard ends shall have a flat profile roughly 3/8” below top of mainline rail.


Avoid dimensional pine lumber. It has a tendency to warp and cup throwing off track alignment.

Mini-mo type modules are intended to subset Free-mo and not replace or exclude an equivalent length standard module. Full width modules are generally more stable and should be used wherever possible. Mini-mos are a subset of the branch line minimum radius specifications.

Updates to Free-mo standards can be found online at
For Ohio Valley Free-mo standards and info, visit

Click below for pages in the directory of TrainWeb sites:
0-9 A B C D E

Visit our Rail Magazine promotion trading partners:      (Click here to add your print rail magazine.)

ad pos61 ad pos63
ad pos62 ad pos64

TrainWeb Reports & Web Sites: Featured Today Past Highlights Previously Featured Slideshows The Big Stories Directory

About Us | Contact Us | Advertise With Us | Silver Rails Country for Train Enthusiasts

shopify site analytics
View TrainWeb.US Stats  | Page updated: 01/21/2019  | Version 2021a10a  | Links  | ©2015-2021 NordiLusta, LLC