Hi all - I’m an HO modeler and honestly never paid much attention to other scales. Recently I came across a load of train stuff from an estate and the boxes were full of several different scales, some of which I’ve heard of, but don’t really know much about. Some specifics:
Nn3 - Is that the same as Z?
What’s the difference between HON30, HOn3, ON3 and O? Aren’t one of those the same as S?
Thanks.
Nn3 uses the same track gauge as Z for 3 ft narrow gauge modeling in N scale. This allows the use of Z locomotive mechanisms with new N scale superstructures for Nn3 as well as the use of Z trucks on Nn3 freight and passenger cars and Z track components.
HOn30 does the same thing with N scale track, mechanisms, trucks. This is usually used to represent 2 ft railroads mostly found in Maine.
HOn3 is narrow gauge in HO and does not match a smaller scale’s track gauge.
On3 is narrow gauge in O and coincidentally matches OO track, but this was not intended. They just happen to be the same.
On30 uses HO gauge track, mechanisms, trucks, for O narrow gauge modeling - this is split between 2 ft and 3 ft prototypes.
S scale (about half way between HO and O) has a track gauge not used in other scales.
Sn42 is S narrow gauge using HO track, mechanisms, trucks. Originally used for 3 ft modeling in S, it has been mostly supplanted by Sn3 using the correct gauge. Sn42 is still used in some countries which actually had 3 1/2 ft prototypes such as New Zealand.
Sn2 uses HOn3 track, mechanism, trucks etc for 2 ft gauge modeling in S scale.
In several of these scales that used parts from a smaller scale, correct scale track, trucks, and mechanisms have partially replaced the smaller scale parts.
See the NMRA site for more info http://nmra.org/standards/sandrp/pdf/S-1.2%202009.07.pdf
Enjoy
Paul
Awesome - Thanks for the very useful info!
Scale is the size of the model relative to the real thing.
Gauge is the distance between the rails.
You can have several gauges in the same scale.
So O, On3, On30 (On2 1/2), On2 are all the same scale. A model is 1/48th the size of the real thing on all of them. A scale person is the same size for all of them.
Several gages borrow the track gauge of another scale in order to recycle the mechanisms for the engines. Sometimes they borrow the track but it usually doesn’t look right (the tie length, width and spacing is usually all wrong).
So if you use Z gauge track with N scale its close to 3 ft gauge in N so is used for Nn3.
If you use N gauge track in HO scale it is close to 30" gauge, so N gauge is used for HOn2 1/2.
If you use HO gauge track in O scale it is close to 30" gauge, so HO gague is used in On2 1/2.
No. 1 gauge (G) is used for standard gauge, 30’ gauge, 36" gauge and meter gauge depending on what scale you choose.
HO is a screwy scale (1/87) because of people messing around with scale and gauge. O scale was actually No. 0 guage which was 1.25" and used 1/4" (1/48) scale. People decided that the models didn’t look right because in 1/48 scale, 1.25’ gauge is 5 ft gauge. So they kept the gauge and the mechanisms the same and figured out that 7mm to the foot scale made 1.25" gauge the closest to standard gauge . In the UK many O scale modelers still use 7mm scale. At some point later somebody wanted smaller scale models. Since 7mm per ft was the scale used by the people making scale models, they made a scale half of 7mm O scale, made the scale 3.5 mm per foot and called it HO (half O).
Just a small correction. In the beginning of European toy trains, gauges were specified and scale was not very specific. #0 gauge was 32mm (being of German origination). In inches, 32mm = 1.26". 1.25" is close enough in the world of toy train tolerances. The English blessed us with the crossover scales - 7mm/ft for 0 gauge - when scales became important. 00 was set at 4mm/ft, and H0 (Half 0) became 3.5mm/ft. 0, 00, 000 (2mm/ft used primarily in Britain), and H0 all substituted O for 0 at some point.
Upon arrival in America, 1/4"/ft was substituted for 7mm/ft for O gauge by US manufacturers. This was in the late '20s and early '30s when rounding metric dimensions to convenient fractional inches was a common US practice. HO got lucky by not being popular enough early enough, and managed to get a nearly exact track gauge at 16.5mm without the fractional inch rounding that O and OO suffered from. HO was the first scale/gauge were the scale was set first, and the gauge followed.
Fred W
delete - duplicate post. I get these automatically using IE7, but no issues when using Firefox.