# Changing to Fn3(1:20.3): More than I realized!



## Steve Stockham (Jan 2, 2008)

For years I have thought that "If only...." and you can fill in the blank about a myriad of different things all relating to 1:20.3 which the NMRA (one of the few things I completely agree with) has designated as Fn3 or "F Scale on 3ft. narrow gauge track. Tony Ferraro (Mr. 1:20) really got the ball rolling and "Uncle Russ" and Outdoor/Finescale Railroader made it one of their crusades. Fast forward 14 years and we now have a legitimate scale all our own! Bachmann and Accucraft have embraced Fn3 and we now have or soon will have a whole plethora of freight cars. 

  Now, in addition to the wonderful kits from Hartford and the brass beauties from Accucraft (to name only a couple) we have J&S Coaches from AMS in mass-produced plastic and soon we will have a matching combine! I was in heaven! _Finally_ I could model in the scale I wanted to!

  Now none of this is really new to most of you! In fact, many of us have a _Spectrum _model from Bachmann but we have run 1:22.5 behind them because that's what was available! Not any more. It started with the Connie but really came into it's own with the K-27! The engine is so large that it virtually _demands_ Fn3 scaled equipment running with it to look right! This is where things got interesting......

  My layout is somewhat typical of a narrow gauge layout in that I have rather drastic elevation changes as well as some tight curves (vs the broad sweeping curves of a standard gauge layout.) While it works very well for engines in 1:22.5 scale (read LGB Mogul or Bachmann Big Hauler) it definitely had some problems with AMS cars with their more prototypical flanges! This was one that I could work with simply by re-ballasting and re-leveling my track.

  The second problem was quite a bit more difficult! The grade changes were making it difficult for a single engine to pull any more than three (sometimes four) cars up the curving 5% ascending grade. If that was difficult, it was nigh on _impossible_ for anything more than four cars coming _down_ the grade and going into the tunnel! Simply put, the _weight_ of these monster cars was too much for my grades! Clearly, something would have to be done if I were to keep modeling Fn3!

  The first thing I decided to do was to order ball bearing wheelsets for my rolling stock. This partially cured the ascending grade problem and a complete re-grading of my layout (not merely an afternoon's work!) should take care of the rest. The only real concern left is the down grade! Making the cars roll more freely will only exacerbate the problem! Since I have to modify the approach to my tunnel as my K-27 needs just a "tad bit more clearance" to successfully navigate it, I figure I will try a couple of new sweeping curves and see if that solves the problem. Speaking of sweeping curves, I am going to have to use a rail bender to make some of my curves more even and less "chunky." This should also improve the layout aesthetically.

  All of this is necessary for me to run a slightly larger scale from 1:22.5 to 1:20.3! Don't get me wrong! I _want_ to model Fn3 as I absolutely adore how it looks! It's just that the decision to go to this scale has been slightly more involved than I had originally envisioned!/DesktopModules/NTForums/themes/mls/emoticons/blink.gif


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## Dwight Ennis (Jan 2, 2008)

it was nigh on impossible for anything more than four cars coming down the grade and going into the tunnel!
You could follow prototype practice and institute low speed limits on those areas where excessive speed could cause derailments or other problems. That may help in the short term. 

I agree btw - *Fn3 RULES!!!*


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## sschaer (Jan 2, 2008)

steve 


pulling cars uphill will stretch the couplers. running downhill compresses them. kadees have quite some slack action, guess about 1/4" each. now if you find a way to use this to construct a brake systems ? if the couplers are compressed a piece of plastic will push on the wheels or axle and therefore brake the car. as soon as the couplers are stretched there's no braking going on. 

of course this would cause some problems when backing up into a siding. 


just a silly idea. not sure if you understand what i'm trying to say. english is not my mothers tongue.


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## Paul Norton (Jan 8, 2008)

Just like the real railroads we abandoned the inner 1:22nd scale dog bone curve after a fire destroyed one of the wooden trestles.
 








 
A wide radius curve with steel bridges was built outside of it to handle larger and heavier locomotives.


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## jimtyp (Jan 2, 2008)

If you isolated the the downward grade track (using plastic joiners for example) you could add some simple electronics so less power is applied on that section.


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## trainmaster1989 (Jan 4, 2008)

I've heard of putting a resistor or diode on the downhill stretch in the direction of the downhill movement, so that the power is automatically dropped a little when the train is going downhill, thus slowing it down. 

Just a thought, not sure if or how well it works. 
Scott


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## Guest (Feb 20, 2008)

I began my layout with Fn3 in mind...that said the kids get the "G" stuff to play with...as I build my collection. I too am rebuilding a graded area of the layout 

cale


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## Steve Stockham (Jan 2, 2008)

I think that a couple of you are laboring under a misconception. My Fn3 locomotives are _all r/c battery!_ Track power won't figure into it! My observations about the downhill grade were merely to contrast what I was able to do with my 1:22.5 stuff (6-7 cars) compared to my Fn3 cars (3-4) before losing it on the downhill! I know that reducing the grade is the only _real_ option so that is what I will do. One thing else: _I am replacing my Aristo turnouts!! _I have ordered turnouts from Oregon Coast and after not getting anywhere at all for six months, I ordered some from the Parker Co. and it has been over three months more without anything! (Yes, I _have _called both places and both have assured me that mine should be done "within a week or two." That was _months _ago!)/DesktopModules/NTForums/themes/mls/emoticons/cry.gif I won't be able to finish the layout without them so I guess I'd better start calling yet again..../DesktopModules/NTForums/themes/mls/emoticons/crying.gif


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## Bruce Chandler (Jan 2, 2008)

Steve,
You might want to take a look at the Swithcrafters line of switches.   I got a few in code 250, but he does offer 332 as well.  I'm very pleased with the operations.


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## blackburn49 (Jan 2, 2008)

You have just described the issues that I will be facing when I begin construction of my Phase III narrow gauge line, which will also involve prototype steep grades.  Fortunately, my line never involved the pulling of more than a few cars. two to four was about typical--more when the firewood for the steam-operated thawing machines was in big demand.


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## joe rusz (Jan 3, 2008)

Steve and all, there's more to converting to Fn3 than track and such. There's the whole issue of scale versus size--a building in 1:24 or even 1:22 is smaller than one done in 1:20.3. These babies take up a lot of real estate and I can see why some folks model one-room general stores and the like. My styrene station has become the focal point of my Living Room Central railroad because it's so big. The Rider's Crossing general store, (now back under construction after the contractor took a few weeks off on Maui) is not quite as large, as it's done in 1:22. My rule is to build  all foreground structures (the ones that sit near the tracks, locos, and operating equipment) to 1:20.3 and to build the others (the ones in the near background) to 1:22.

Now _problemo numero dos_: I have three Barry-ized Bachmann 10-wheelers and about 30 freight and three passenger cars that are 1:22. I worked hard detailing much of the rollling stock and hate to dump it. The locos, I'll keep. One of them, converted to a 2-8-0 by Barry, is part way to becoming an obscure Lima Connie whose boiler looks a lot like the Tweetsie Baldwin boiler, which kinda tapers down toward the smokebox. I actually built part of the cab and diddled around with various steam and sand domes (Fletch suggested using deoderant spray caps). But as often happens, there's been a strike at the railroad's shops and that project is in limbo (now there's a town name for ya!).

I guess what I wanna say is that I'll super-size the locos (too much money invested in the drivetrain) and remainder the rolling stock. Maybe turn one of the 10-wheelers into a mogul. Coulda just bought one, but what's the fun of that?

Anybody remember where the boiler-building PDF files are in Fletch's library?


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## Dr Rivet (Jan 5, 2008)

Steve 

Wow.. four or five cars on a 5% grade. Better go check out prototype operations. If you get to seven or eight with ball bearings, you are where the prototype would be. Runaways are now possible in 1:20.3 with the coasting drive of the Bachmann K-27. Ralph Bagnall-Wild in the UK described in the last G1MRA newsletter how he put R/C servo operated brakes on some of his passenger cars to conrol the train while standing on a grade in a station. 

Welcome to the real world of physics with BIG (well bigger) trains. 

Cheers 

Jim


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