Standards
Model railways only work because everybody keeps to the same measurements. Two organisations write them down: MOROP with the NEM for Europe, and the NMRA with its Standards and Recommended Practices for North America. TRAX works with those measurements, and this page says which.
MOROP and the NMRA publish the standards themselves, free, on their own sites. We point at them and do not copy them: the texts are theirs, the numbers that follow from them we simply use, because a measurement is a fact.
Where to find them
Which measurements TRAX uses
- The loading gauge comes from NEM 102 and NMRA S-7. TRAX works with about 4.8 metres in real life, which comes to 55 millimetres in H0. That decides how high the ground over a tunnel lies and how much room is left under a bridge.
- The platform distance is 1650 millimetres in real life from the track's centre, according to NEM and UIC. A platform you draw along a track lands there by itself.
- The scale decides everything with a real measurement. TRAX knows T 1:480, Z 1:220, N 1:160, TT 1:120, H0 1:87, OO 1:76, S 1:64, O 1:48, I 1:32 and G 1:22.5.
- The gauge is carried by each library, because it belongs to the track system and not to the scale. H0 on 16.5 millimetres is standard gauge; H0m and H0e are the same scale on narrower track.
- Minimum radii are in NEM 111. TRAX does not enforce them: which curve will do depends on what runs on it, and you know that better yourself.
What TRAX does not take from a standard
The reach of an arm is not a standard but a rule of thumb, and one that shapes every layout: about 600 millimetres if you can only get at it from one side and 1200 if you can walk around it. TRAX works it out and says it, but does not stop you.
The same holds for grades. We limit a road to 12 per cent because a steeper road does not look right, but what your track can take depends on your locomotives.