FREMO

The Friendship of European railway modellers (Freundeskreis Europäischer Modellbahner, FREMO) is a modular rail transport modelling standard. Individual track and scenery modules are built to a common standard and are joined together to make larger model railway layouts. The FREMO standards were created following a meeting in Europe in 1981.

Single track modules are 500 mm wide, of variable length, viewable from both sides. Each module comes with adjustable legs, to create a uniform top-of-rail height of 1300 mm above floor level. Modules are physically joined together using three 12 mm holes and hand-tightened M8 bolts with washers and wingnuts. The electrical inter-connection uses two Banana connectors per track bus, over which Digital Command Control (DCC) signalling running at 14 volts is used for train control. Track uses Code 83 rails (0.083 in high), with a minimum curve radius of 2000 mm; representing 175 m at 1:87) and fixed track centre-line spacing of 46 mm; representing 4 m separation at 1:87 scale).

Some general aspects, such as rigid construction of modules, are derived from the Normen Europäischer Modellbahnen NEM 900 standards published by MOROP. In 1995, the North American Free-mo standards were based on those of FREMO, with a number of changes made.

North American Standards
In 1994 Chris Palomarez and Art Armstrong at the San Luis Obispo Model Railroad Club (SLOMRC) developed the Free-mo Standard based on the European FREMO concept.

N-scale variant
In 2004, the traditional Free-mo standard was adapted for N scale (1:160). It uses Code 55 rail at a nominal height of 50 in. Curves should not have a radius of less than 22 in on the main line and use turnouts sized No. 6 or larger.

NMRA British Region Freemo Standard
In 2011 the NMRA British Region released a set of standards called Freemo, Recommended Specifications For HO Scale Modules.