The three main track standards in use are: -
In addition there are various narrow gauge, broad gauge, and also ‘tramway’ type trackwork standards. It is important to maintain a specific track standard throughout the layout, compatible with the wheel standard of the vehicles intended, whether Coarse Scale, Finescale or ScaleSeven, or other. Coarse Scale and Finescale use the same 32mm rail spacing (slightly under prototype), whereas ScaleSeven has a wider gauge (accurate to prototype). Coarse Scale track usually uses a rail profile larger than Finescale and ScaleSeven. (See the Revised Manual ‘Standards’ section for detailed information.) Finescale also has two recognised variants called O-Medium Fine (O-MF) and O-Super Fine (O-SF). Finescale, O-MF, and O-SF track and pointwork is designed to accommodate Guild standard Finescale wheels. However experience has shown that some commercially manufactured cast iron wheels nominally produced to the Guild Finescale tolerances do not always run successfully through O-MF and O-SF pointwork because the wheelset check gauge is outside the Finescale tolerance. ScaleSeven track must only be used with ScaleSeven wheels, and likewise Guild standard Coarse Scale wheels with Coarse Scale track.
Please note that some commercially available coarse scale vehicle wheels do not comply with any Guild standards and these should be treated separately.