Please Explain 2-Rail Scale

Look at Atlas or 3rd Rail for RTR models right now.

Why do you think the trucks don't swivel?

I bet you mean modern diesel pilots that are attached to the body like the real ones are.

Diesel fix pilots | O Gauge Railroading On Line Forum (ogaugerr.com)

Trucks are the large assemblies that have the wheel sets, brakes, etc.

https://condrenrails.com/Diese...es/trucks/index.html

@Scott J posted:

For a small layout 3-railer like me, the term "scale" is used rather loosely. Like my Rail King Mikado is semi-scale (compressed) and my Premier K-4S is scale. But both are being run on 3 rail track with an 036 radius. So if you are doing 2 rail scale, I get the part about Kaydees and 2 rail trucks. On the trucks, the wheels are distinctly different and obviously don't have the "pizza cutter" flange. But who sells these? I have a set from an eBay purchase that are made in Japan that are really unique/odd with huge axles and strange wheel/truck interface (don't know the maker). Then, I get that Atlas sells 2 rail track but what is the minimum radius and is that like HO where the min radius is true prototypical. Finally, where do you get 2-rail engines and are these like HO where the trucks don't swivel? I'm guessing that 3rd Rail but what do these engines/cars cost? Can you get 2 rail versions of MTH and Lionel engines?

I envy anyone that has the space/talent to run 2RS. Here is your chance to brag about your unique version of the O gauge hobby. Would make a great article in the O gauge magazine if it hasn't already been featured.

S

Look to Atlas. Atlas is producing the MTH Premier engines with scale wheels and fixed pilots. I've been buying the scale wheel offerings from MTH since 2009 and haven't looked back. It made things a bit complicated for a while as I belong to three rail clubs, but (except for the switches) the Atlas three rail track supports scale wheels just fine provided the curves are large enough. At AGHR we used Ross #5 switches which worked fine.

You're correct Joe. I'm a little fuzzy on the terminology.

Matt, you don't remember that I did drop by the club on a Saturday and we met. Am do for another visit. I did try a car with scale wheels. Great on straight sections but a no-go on 036.

Scott

See the O Scale Central website and be sure to check out the O Scale 2 Rail Product Guide menu at the top for all kinds of O Scale 2-Rail related products.

Also, see the O Scale Central You Tube channel and the O Scale Central Facebook page for all things O Scale 2-Rail.

Scott

"Please Explain 2 Rail Scale"

That's easy: the tracks have (2) rails, and the models that run on it (the track) are "scale" models... 

Mark in Oregon

I realize this is just me, but I always thought:

2RS: Everything on the layout as scale as possible.  Scale flanges on wheels, Kadee or similar scale couplers.  This includes S as well as O.  Fixed pilots preferred.

3RS: Everything on the layout as scale as possible with the minimal changes required to accommodate 3-rail track, primarily for tighter radius turns in smaller rooms.  Kadee or similar scale couplers.

Hi-Rail (2- or 3-rail):  Everything as realistic as possible using non-scale/large couplers.  Scale trains/ structures/ etc., if possible, but tinplate track okay.  Large flanges on wheels, but can use scale wheels if correct track.

Traditional:  Hi-Rail with less (lot less?) realism.  Traditional tinplate track.  Scale not adhered to.

Toy: Whatever floats the owner's boat.

I am currently Hi-Rail going to 3RS.  Wish I had the room for 2RS, but I like BIG engines as well as switching.

Here’s a side by side showing two MTH UP ES44AC’s. The primary differences between the two are the axles (can’t be seen), the fixed pilots, and the full length handrails. I had a duplicate two rail roadnumber, so I bought a 3-rail dummy and body swapped them to get a powered 2-rail unit in a number I didn’t have.

(my photo)

Here’s a vid showing a MTH ES44, two AC44s, and an SD70 hauling an autorack train around my home floor layout.

Great video. If I'm lucky I get to see that (more or less) as I drive through Mojave going north to the mountains.

And dont forget that "2 rail scale" isnt really scale either unless you go Proto 48...

@Scott J posted:

You're correct Joe. I'm a little fuzzy on the terminology.

Matt, you don't remember that I did drop by the club on a Saturday and we met. Am do for another visit. I did try a car with scale wheels. Great on straight sections but a no-go on 036.

Hi Scott.

I retired three years ago and moved to Arizona. I'm a life member of AGHR but I'm a member of the Paradise and Pacific Model Railroad Club in Scottsdale at McCormick-Stillman Railroad Park. I'm still running trains from time to time and working on a home layout. Hopefully I'll take a road trip back to California this year and visit the club.

For me I never had 3 rail, I had HO when I was a boy and when I got older and saw how beautiful and realistic 2 rail was I was hooked.  If your ok with 3 rail have fun.

@Scott J posted:

For a small layout 3-railer like me, the term "scale" is used rather loosely. Like my Rail King Mikado is semi-scale (compressed) and my Premier K-4S is scale. But both are being run on 3 rail track with an 036 radius. So if you are doing 2 rail scale, I get the part about Kaydees and 2 rail trucks. On the trucks, the wheels are distinctly different and obviously don't have the "pizza cutter" flange. But who sells these? I have a set from an eBay purchase that are made in Japan that are really unique/odd with huge axles and strange wheel/truck interface (don't know the maker). Then, I get that Atlas sells 2 rail track but what is the minimum radius and is that like HO where the min radius is true prototypical.

Even in HO where the minimum is either 18"R or 22"R the track is much sharper than "true prototypical". Meaning it is rare for the prototype to have a curvature as sharp as this. Especially on the mainline. It's just the minimum radii that most HO models are designed to run on. With O scale the minimum is roughly double that of HO for some models but even a little more for other models. For example almost all 4 axle diesels will run on 36"R (O72 in 3 rail) and maybe even a little bit tighter but 6 axle diesels may require 40"R (O80). There is no one answer for everyone. The minimum radius needed for O scale track would be track that will allow you to run whatever equipment you have. Most of my trains (I have not tested them all) will run comfortably on 49.9"R (O99) track. Some of them even tighter.

Finally, where do you get 2-rail engines and are these like HO where the trucks don't swivel? I'm guessing that 3rd Rail but what do these engines/cars cost? Can you get 2 rail versions of MTH and Lionel engines?

Beth at The Public Delivery Track has 2 rail engines and cars in stock. You can get 2 rail equipment from MR. Muffins but he doesn't really stock any. Then of course there is eBay and the O scale Yardsale (which I find hard to navigate). Last but not least there are always tons of engines at any of the 2 rail shows. With 2 rail you might not get the instant gratification that you can get with 3 rail but I have always found whatever I wanted eventually. For some things it just takes a little patience.

No, you cannot get Lionel 2 rail engines. They just don't make any but there a couple of rare exceptions from Lionel. MTH used to make 2 rail engines . They were called "Scale Wheels" but ever since the Mike Wolf retirement they haven't made any. By flipping a switch and/or converting the wheels you could run them on 3 rail track. Some 3 rail guys liked the fixed pilots. Fortunately, as noted above Atlas is producing some of the former MTH engines that they have in 2 rail. There is a possibility that MTH will produce 2 rail again in the future but these are just rumors and no one really knows if it will happen.

I envy anyone that has the space/talent to run 2RS. Here is your chance to brag about your unique version of the O gauge hobby. Would make a great article in the O gauge magazine if it hasn't already been featured.

S

@Scott J posted:

For a small layout 3-railer like me, the term "scale" is used rather loosely. Like my Rail King Mikado is semi-scale (compressed) and my Premier K-4S is scale. But both are being run on 3 rail track with an 036 radius. So if you are doing 2 rail scale, I get the part about Kaydees and 2 rail trucks. On the trucks, the wheels are distinctly different and obviously don't have the "pizza cutter" flange. But who sells these? I have a set from an eBay purchase that are made in Japan that are really unique/odd with huge axles and strange wheel/truck interface (don't know the maker). Then, I get that Atlas sells 2 rail track but what is the minimum radius and is that like HO where the min radius is true prototypical. Finally, where do you get 2-rail engines and are these like HO where the trucks don't swivel? I'm guessing that 3rd Rail but what do these engines/cars cost? Can you get 2 rail versions of MTH and Lionel engines?

The specific questions you asked have been previously answered quite well.  I want to clarify though where 2R O scale came from.

There has always been the diverging path of Model Trains vs Toy Trains, with many falling in a middle ground. Even if you look at the current Lionel O 3R offerings there are clearly those for the Toy market and those offered for the Scale Model Train market.  Some fall somewhere in between.

2 Rail O Scale was around prior to HO.  HO got it's name from being Half (H) O Scale.  The gauge of the track was half that of O 1+1/4" vs HO 5/8".  While the actual scales settled to current NMRA HO 1:87 vs O 1:48.  The aim being to make accurate Scale Models of Real Trains, not Toys Trains for Kids to play with.

During the heyday of HO, in the late 1950's to early 1970's, many HO "models" became very Toy Like, for kids to play with.  They actually were priced for far less than the 3R toy trains.

However, 2R O Scale "mostly" held it's ground, as there were many 3R offerings to fill the O size toy market.  There were some exceptions such as Kusan, particularly their K-Series.  There were also some European brands marketed through AHM and others (ie. Atlas), that while Scale Sized, didn't have the level of detail we see today.  Also before "standardization" to Kadees, there were various coupler types.

So in a general sense, 2R O Scale is easier to define than 3R O Scale.

I have been messing around with 2rail O-gauge for about 50 years and when I built my current layout (20 x 40) I decided on a simple plan with very broad curves (ca. 96" radius) that would accommodate articulated locomotives, but even with the large curves I thought the boiler swing of the big engines just didn't look very good. Ultimately, I decided to stick with smaller engines and some F units pulling mostly 40 and 50-foot cars. They give a much more satisfying appearance of "flowing" through the curves and track work.

Ultimately it's up to you and what you think looks good and is fun to operate. There is a lot of 2rail equipment on the market: check out Brass Trains.com for an indication of what's available in brass (832 items in stock as of today). Atlas has nice 2rail stuff and all kinds of oldies (All Nation, Ambroid, USH, etc.) turns up regularly on e-Bay. Have fun with it!!

From Phil:

Even in HO where the minimum is either 18"R or 22"R the track is much sharper than "true prototypical". Meaning it is rare for the prototype to have a curvature as sharp as this. Especially on the mainline. It's just the minimum radii that most HO models are designed to run on. With O scale the minimum is roughly double that of HO for some models but even a little more for other models. For example almost all 4 axle diesels will run on 36"R (O72 in 3 rail) and maybe even a little bit tighter but 6 axle diesels may require 40"R (O80). There is no one answer for everyone. The minimum radius needed for O scale track would be track that will allow you to run whatever equipment you have. Most of my trains (I have not tested them all) will run comfortably on 49.9"R (O99) track. Some of them even tighter.

This is one of the things I was most curious about. I was under the impression that HO was true absolute prototypical with respect to track radius. What Phil has pointed out above is a surprise. What is not surprising then is that even O99 track is just getting where you need to be so that, for example, a large steam engine will run with the tender hugging the engine so that the engine and tender appear as a single unit. I have a semi-scale S2 6-8-6 turbine and the PS3 drawbar is really long so that the engine can negotiate my O36 curves. It is hard for me to imagine a radius large enough for the engine to be able to run or appear to run as with the engine and tender aligned. The "boiler swing" B Smith refers to is something I just have to live with. I do have a couple of sections of track where I can ignore that and I tend to focus on those when running laps with larger engines. One of my great laments is that I didn't know enough to least design around O42 or O56 that would allow me to run so many additional MTH Premier engines.

Most CA homes don't have basements. So my man-cave/train-room is about 14' x 14' and maybe not even that big. It has to accommodate my layout, desk/workbench, TV, book case (I cut a hole in either side of this at the 4 ft level and it became part of the layout) and train storage. It was one of the original bedrooms in what was a small house before add-ons. My daughters room on the other hand is big enough for a giant L shaped layout with O72 curves and my wife PROMISED me I could have it after my daughter graduated and moved out. When the time came I got a big fat NO. Long term I'm to try and expand to where the desk is but that's somewhere in the future. Yes, there is a whole lot of suspension of disbelief on my layout but that has never dimmed my enthusiasm for the hobby.

Thanks for all of the great replies!

Suppose you were modeling a 1-degree mainline curve: that would be about a 66-foot radius in HO. So even in HO you aren't going to be able to have realistic curves, unless maybe it's something like the old Baltimore docks with a tiny 0-4-0 switcher.

"Here’s a side by side showing two MTH UP ES44AC’s......"

If you look, (once seen cannot be unseen) the sideframes on all MTH diesels stick out way to far from the body of the engine.  The truck frames should not stick outside the body of the locomotive.  All is not lost.  It is an easy fix, all you need to do is remove the frames drill and tap new holes just a bit so the truck frames will not protrude outside the body.  Does not take long to do.

- Crank

Scott, I think if you watch John Sethian's video on his 2 rail O scale layout it might answer some questions.