Fn3

[az2rail]

What is Fn3? I thought it was the size that 20.3 narrow gauge would be if it as on standard gauge track for that size. but now I'm not sure. Bruce

[Barry BBT]

Bruce,

Fn3 is supposed to be a means to simplify 20.3 narrow gauge.  It has some further delineation from other gauge 1 locos and rolling stock.

When it first came out it confused me, I figured I would learn it through usage and reference, but that has not occurred.  20.3 Narrow gauge is simple and perfect.

Barry - BBT

[Steve Stockham]

  Fn3 is F Scale but on 3ft. narrow gauge track. 1:20.32 is the scale ratio for this running on Gauge I (45mm) track which is the track that we use for Large Scale. The gauge of track is sometimes referred to erroneously as "G Gauge".
 Standard Gauge in F Scale would runn on 70.64mm and the engines would be correspondingly larger! The scale ratio is still 1:20.32 or "F"! When you look at the Fn3, the n3 merely refers to the gauge of track of the prototype. In this case n3 refers to 3ft. If we were to model a Maine narrow gauge railroad that runs on 2ft. Gauge track then the scale would be 1:20.32 or Fn2 which models to 30mm. O Gauge track is 32mm so it's considered close enough to the actual gauge to use.
 I like the Fn3 designation rather than Large Scale 1:20.3 as it is more descriptive and also because F is a legitimate scale in it's own right as there are commercial models in F Scale Standard Gauge as well as Fn3! Hopefully, this answered your question.

[Jake]

Well, Fn3 stands for "F" Scale (1:20.3, which is just a proportion of it's size to the real thing's) "n" stands for narrow gauge, and "3" stands for 3 feet between the rails. This pretty much applies to all scales. e.g, HOn3, it is the same as Fn3, aside in the actual model's size. HOn3 means "HO" scale, (1:87.086 [Though mostly just put down as 1:87, or 1:87.1]) "n" for narrow gauge, "3" for three feet between the rails. But, there are some scales (Technically gauges in this area) with two digits. Like HOn30. No, the rails are not 30 feet apart, but 30 inches. HO = HO scale, n = narrow gauge, 30 = 30" between the rails. Or Sn42 S= S scale (1:64) n = narrow gauge, 42 = 42" between the rails.

Get how it works now?

[Solar]

... as there are commercial models in F Scale Standard Gauge as well as Fn3!

That's something I haven't run across yet!  I did know that Iron Creek is making tie strips for F Scale standard gauge, but I didn't know there was anybody making commercial models for that gauge.  Could you give us a pointer or two to their web sites?

[Paul W.]

Solar,
I don't remember if it was here or on LSOL, but the Bachmann 1:20.3 diesel was converted into a standard guage, and looked good.

[az2rail]

Thanks for the replies,guys. Steve, that's what I thought it was. You explained it nicely. I was of the same impression, but while cruising some web pages, I started to get confused. I think they are the ones confused.I am mostly on30 these days, but I bought a Bachmann 2-8-0 saturday. I knew that is is narrow gauge on standard G track, which makes it larger than the normal G than I am used to. While checking on some cars, I came across "Fn3". I never heard of it before. Like you Berry, I figured, I would figure it out, but this made it much clearer. Thanks. Bruce

[zubi]

Bruce,

Fn3 is supposed to be a means to simplify 20.3 narrow gauge.  It has some further delineation from other gauge 1 locos and rolling stock.

When it first came out it confused me, I figured I would learn it through usage and reference, but that has not occurred.  20.3 Narrow gauge is simple and perfect.

Barry - BBT

Barry, The reason why this kind of denomination is confusing, is that it mixes model scale with prototype gauge. In other words it mixes model information with prototype information, neither of which are necessarily and universally corresponding (as is the case for other prototype gauges in 15mm scale for example). Best wishes from Tokyo, Zubi

[zubi]

If we were to model a Maine narrow gauge railroad that runs on 2ft. Gauge track then the scale would be 1:20.32 or Fn2 which models to 30mm. O Gauge track is 32mm so it's considered close enough to the actual gauge to use.

Nice try Steve , but for 2ft prototypes we have a well established 16mm scale not 15mm scale. This works out perfectly well to 32mm gauge standard model O gauge track. Best wishes from Tokyo, Zubi
PS I am surprised to hear that 7% difference is close enough for the advocates of 1:20.32... This makes me think that we can safely go back to the good old 1:22.5 scale for 3ft prototypes - after all a minor proportion of all narrow gauge - the gauge error at 4mm absolute difference and 10% relative is just 3% greater! Good news !

[Steve Stockham]

Heh, heh, heh....oh well! It was worth a shot! I really was just trying to explain the concept and I have heard about people using 32mm track because it is close and 32mm track is readily available. As far as 1:22.5 is concerned, it works for me! (I told you that we agree more than we disagree on most things! )  Well over 3/4ths of my rolling stock is 1:22.5!

[zubi]

Steve, I am sure that we agree , sorry for not respoding to your post from a couple of weeks ago, I got caught up in things a bit, but I might still respond ... I am not sure what most of my rolling stock is... actually in Japan the absolute majority of it is 15mm scale which some persons refer to as 1:20.32 ... and it is growing fast.... availability of nice narrow gauge live steam is an excellent reason for its fast growth! Best, Zubi

[Steve Stockham]

  I agree that 15mm scale would and should have been the designation! It would have been universal and less confusing but then hey, when have Americans done it the easy way? We still stubbornly cling to inches feet and yards when metric has been proven to be easier and more accurate to use!

[Charlie Mutschler]

Morning, Steve - didn't I just hear on the radio this AM that the EU has decided to drop its efforts to force the UK and Ireland to adopt the metric system?  Apparently we're not alone in having a preference for our weird units of measurement.  And, Zubi, the English and US use  different gallons, just to make this more interesting!  Personally, though, I'm quite satisfied using SAE units, much to dismay of the various science people in my family (father, aunt, uncle, brother) - all of whom have cheerfully been using metric units for years.  Maybe that's why I went into history as a profession. 

Charlie Mutschler

[japasha]

Zubi,

I need you to contact me at my regular Email. I'm looking for Japanese locomotive models by Otaki. Rolling stock as well. I believe the scale is 1:50

Thanks,

Jim Pasha
[email protected]