anybody else here lack space for 2 rail?

Brandon Cole posted:

New Haven Joe posted:

The biggest problem with O 2-rail is the large radius needed to run most equipment.  Most of the medium to large O scale equipment needs a minimum of 60 inch radius (O-120) and large switches.  This is the primary reason that O 2-rail is not very popular.   

I am am guessing other manufacturers than MTH need wider radius? MTH big boy will operate on 54" radius.  In the video link below, the Big Boy derails on uneven track by the farm on the club layout, but handles everything else, including a hidden 36" radius curve just fine.

Thank you. 

An MTH scale-wheeled Big Boy doesn't have a tail beam and is essentially a 3-rail locomotive with scale wheels. They will get through 36" radius provided the track is level and consistent (no kinks).

AGHRMatt posted:

Brandon Cole posted:

New Haven Joe posted:

The biggest problem with O 2-rail is the large radius needed to run most equipment.  Most of the medium to large O scale equipment needs a minimum of 60 inch radius (O-120) and large switches.  This is the primary reason that O 2-rail is not very popular.   

I am am guessing other manufacturers than MTH need wider radius? MTH big boy will operate on 54" radius.  In the video link below, the Big Boy derails on uneven track by the farm on the club layout, but handles everything else, including a hidden 36" radius curve just fine.

Thank you. 

An MTH scale-wheeled Big Boy doesn't have a tail beam and is essentially a 3-rail locomotive with scale wheels. They will get through 36" radius provided the track is level and consistent (no kinks).

That makes sense.

Thank you. 

MTH has made mechanisms on large steamers in 3 rail that are not as capable of sharper radii than they could be.    The side rods (rods connecting the drivers to each other) are supposed to be jointed at each crank pin to allow the drivers to move up and down and side to side independently.    That allows them to go around curves.   MTH uses a solid side rod with no joints.    They do this in 3 rail probably because LIonel has done it for a century.    Lionel does not do 2-rail however.   It works in 3 rail because they make all the drivers except the ones a the front back, blind (no flanges).    So whatever the wheel arrangement, in terms of curves, they only have 4 drivers because the blind ones can slide way off the rail.   They put flanges on the 2 rail locos, but did not put hinges on the side rods.   It is surprising they can go around any curves at all!   

I have a fleet of 2-rail medium size locos from various scale mfg including Weaver, Sunset 3rd Rail , US Hobbies, and Max Grey.    These include 2-10-0, 4-8-2, 2-8-2, 2-10-2 and 2-8-0.     They will all go around 48 inch radius.    The 10 driver ones like 52 inch better.   Some of the 2-8-0s will go around 36 or so.    All of these scale locos have side rods with joints at each driver as do the prototypes.

If you are interested in 2-rail, you would find it worthwhile to look into some other 2 rail mfgs and go to some 2 rail shows to see what is available.    There is a lot of stuff new and used available at all sorts of different prices from very high end brass to basic plastic.

,

prrjim posted:

MTH has made mechanisms on large steamers in 3 rail that are not as capable of sharper radii than they could be.    The side rods (rods connecting the drivers to each other) are supposed to be jointed at each crank pin to allow the drivers to move up and down and side to side independently.    That allows them to go around curves.   MTH uses a solid side rod with no joints.    They do this in 3 rail probably because LIonel has done it for a century.    Lionel does not do 2-rail however.   It works in 3 rail because they make all the drivers except the ones a the front back, blind (no flanges).    So whatever the wheel arrangement, in terms of curves, they only have 4 drivers because the blind ones can slide way off the rail.   They put flanges on the 2 rail locos, but did not put hinges on the side rods.   It is surprising they can go around any curves at all!   

I have a fleet of 2-rail medium size locos from various scale mfg including Weaver, Sunset 3rd Rail , US Hobbies, and Max Grey.    These include 2-10-0, 4-8-2, 2-8-2, 2-10-2 and 2-8-0.     They will all go around 48 inch radius.    The 10 driver ones like 52 inch better.   Some of the 2-8-0s will go around 36 or so.    All of these scale locos have side rods with joints at each driver as do the prototypes.

If you are interested in 2-rail, you would find it worthwhile to look into some other 2 rail mfgs and go to some 2 rail shows to see what is available.    There is a lot of stuff new and used available at all sorts of different prices from very high end brass to basic plastic.

 

,

Will more than likely start buying Sunset models but I have pre order deposit on the MTH 611 2 rail hopefully it will be fine on the 54" radius like it calls for. 

I hope it works out for you too.    I have had my hands on an MTH steamer for a few years.   They could be changing.

Don't discard the older USH and MG models.   They are very sturdy and well built.   And mechanisms are strong.    You can put whatever electronics in them you want.

I personally prefer DCC since it is an open system.  That means any decoder works with any control system.   And there are lots of very good sound decoders available.     An aside is that I can ask my HO buddies questions since they use DCC too.

New Haven Joe posted:

I think that the best choice for people who want to run O scale trains is to join a club or modular group.  You may be able to form a group if there is not one nearby.  

 

Joe,  Definitely agree with you on joining/creating a modular group.  They can be a lot of fun, a lot of work too, but very rewarding.  Also helps promote the hobby and more importantly the scale.  Seeing is believing!   

Mike DeBerg posted:

New Haven Joe posted:

I think that the best choice for people who want to run O scale trains is to join a club or modular group.  You may be able to form a group if there is not one nearby.  

 

Joe,  Definitely agree with you on joining/creating a modular group.  They can be a lot of fun, a lot of work too, but very rewarding.  Also helps promote the hobby and more importantly the scale.  Seeing is believing!   

I totally agree with Mike's statement about promoting the hobby. I wouldn't have been serious about 2-rail & BNSF models, had I not seen Mike's club's layout at the annual Galesburg Railroad Show in 2009. Until then I had seen 2-rail models at stores but I had never seen a 2-rail layout. I was still holding on to some of my HO models but after seeing the O-Scale models on his Twin-Cities layout, I was impressed enough to stay with 2-rail.

Thanks,

Naveen Rajan 

Hi Naveen, 

Thank you!!  Would be great to have you run some of your O Scale equipment on the layout sometime!   If you're ever interested in building a module definitely would welcome that as well! 

It is a compromise.  The 3-rail scale folks are heading toward the same radius curves - they are paying very close attention to accuracy above the rails, and very soon they will discover that it isn't the center rail that enables them to have sharp curves.

I didn't have room for a long time-so I'm building a second floor to my 40 x 80 foot shop. 

Should be able to fit a train or two in there....

bob2 posted:

It is a compromise.  The 3-rail scale folks are heading toward the same radius curves - they are paying very close attention to accuracy above the rails, and very soon they will discover that it isn't the center rail that enables them to have sharp curves.

And when they do, their model railroading "Epiphany" will happen, and it will probably go along the lines similar to this:

Coming from a life long involvement in HO, it was during my brief experimentation with 3 rail I learned:

* I was "okay" with the third rail as long as I was running traditional trains in a traditional setting on traditional tubular track.  Mentally I was okay because mentally I was playing with "toy trains". They didn't have to look "real".

* Then I wanted more realism, so I started heading toward "hi-rail"... starting first with the removal of tubular and installing GarGraves track and switches.

* Then I wanted MORE realism and start moving toward scale-sized 3 rail rolling stock.

* Then I wanted MORE realism with the running characteristics I was used to in my decades in quality HO and tried an Atlas SW. 

* The Atlas SW helped a lot, as it ran better than any of the other 3 rail engines (but not as good as my  HO ran), but then I noticed that I was evolving right back to scale modeling... and suddenly I experienced my "Epiphany": That third rail sucked and I could never be happy scale modeling looking at it.

I asked myself "Who am I kidding? I can't be happy with scale trains on three rail track. No way, no how."

So, I returned to 2 rail and soon wound up right back in HO where I started out with on my way to becoming a "serious" modeler back in 1962.

I suspect that many others have, or will, follow the above path if they begin to pursue a path toward more realism.

Mike DeBerg posted:

Mike, Central Illinois.  Bloomington to be exact.  We are expanding and will do more shows in the Midwest!

Mike,

Where in Bloomington? Do you have a permanent location? Sending you an email for more information.

laming posted:

bob2 posted:

It is a compromise.  The 3-rail scale folks are heading toward the same radius curves - they are paying very close attention to accuracy above the rails, and very soon they will discover that it isn't the center rail that enables them to have sharp curves.

And when they do, their model railroading "Epiphany" will happen, and it will probably go along the lines similar to this:

Coming from a life long involvement in HO, it was during my brief experimentation with 3 rail I learned:

* I was "okay" with the third rail as long as I was running traditional trains in a traditional setting on traditional tubular track.  Mentally I was okay because mentally I was playing with "toy trains". They didn't have to look "real".

* Then I wanted more realism, so I started heading toward "hi-rail"... starting first with the removal of tubular and installing GarGraves track and switches.

* Then I wanted MORE realism and start moving toward scale-sized 3 rail rolling stock.

* Then I wanted MORE realism with the running characteristics I was used to in my decades in quality HO and tried an Atlas SW. 

* The Atlas SW helped a lot, as it ran better than any of the other 3 rail engines (but not as good as my  HO ran), but then I noticed that I was evolving right back to scale modeling... and suddenly I experienced my "Epiphany": That third rail sucked and I could never be happy scale modeling looking at it.

I asked myself "Who am I kidding? I can't be happy with scale trains on three rail track. No way, no how."

So, I returned to 2 rail and soon wound up right back in HO where I started out with on my way to becoming a "serious" modeler back in 1962.

I suspect that many others have, or will, follow the above path if they begin to pursue a path toward more realism.

Exactly!

My 2 cents on 2 rail.  (No pun intended but if it works- whatever) I had once considered getting into 2 rail O scale but because of the curve requirements I was just going to make a long switching yard with multiple track. I'd still have trains to run and switching can be enjoyable. But, then I realized I'd still want a loop of track just to run a train from time to time. Then I realized what I liked about toy trains in the first place and that was the operating accessories. O scale doesn't have operating accessories unless I were to scratch build. So, I'm back at where I started.

Ah, Russell, you tempt me!

There is another option:

2 rail hi-rail

We don't need the third rail anymore, but the oversize flanges are nice for operational reliability and to keep the curve radius manageable.  John Armstrong solved the curve issue a long time ago--just cover up the sharp curves with mountains or view block and leave the straightaways and "cosmetic" curves exposed.

Love Signals not to mention the Big Boy !

I suspect that there are more O-scalers with space problems than a lot of people would think. I suspect that a lot of us are going to have to do the shelf-layout thing.

I have been watching the doings of the Dallas Fort Worth O Scalers for quite a while now. I've noticed that they tend not to run big locomotives and long cars on their modular display layouts, but they do run a lot of four-axle diesels (Mostly first-generation switchers and diesels) and mostly use 40 foot boxcars and reefers and fifty foot flatcars.

I have noticed that a lot of British model railroaders have the same space problems we do and even more so, since most of them are in OO and N. I've started reading British model magazines to see what solutions they choose to deal with the problem.

Mister_Lee posted:

I suspect that there are more O-scalers with space problems than a lot of people would think. I suspect that a lot of us are going to have to do the shelf-layout thing.

I have been watching the doings of the Dallas Fort Worth O Scalers for quite a while now. I've noticed that they tend not to run big locomotives and long cars on their modular display layouts, but they do run a lot of four-axle diesels (Mostly first-generation switchers and diesels) and mostly use 40 foot boxcars and reefers and fifty foot flatcars.

 

I have noticed that a lot of British model railroaders have the same space problems we do and even more so, since most of them are in OO and N. I've started reading British model magazines to see what solutions they choose to deal with the problem.

 

 

Model Rail is a great publication for British railroad modeling (though some modelers actually model North American prototypes). I occasionally pick up copies from Barnes and Noble. Some of the modeling is literally scary with respect to the level of accuracy in matching the prototype. European models tend to be shorter which is more compatible with smaller switching layouts and sharper curves, but Geeps and 40-foot cars can make it through some pretty sharp curves.

WITZ 41 posted:

Mike DeBerg posted:

Mike, Central Illinois.  Bloomington to be exact.  We are expanding and will do more shows in the Midwest!

Mike,

Where in Bloomington? Do you have a permanent location? Sending you an email for more information.

As mentioned, don't have a permanent location.  We setup at area events and regional shows. When we have enough in our group perhaps that will a possibility!

Mister_Lee posted:

I suspect that there are more O-scalers with space problems than a lot of people would think. I suspect that a lot of us are going to have to do the shelf-layout thing.

I have been watching the doings of the Dallas Fort Worth O Scalers for quite a while now. I've noticed that they tend not to run big locomotives and long cars on their modular display layouts, but they do run a lot of four-axle diesels (Mostly first-generation switchers and diesels) and mostly use 40 foot boxcars and reefers and fifty foot flatcars.

 

I have noticed that a lot of British model railroaders have the same space problems we do and even more so, since most of them are in OO and N. I've started reading British model magazines to see what solutions they choose to deal with the problem.

 

 

Definitely agree..  There aren't as many groups with modular/portable O Scale layouts that run the bigger equipment, especially in 2 rail, but there are some!  Including the group we have in Bloomington. 

Russell - Idaho USA posted:

laming posted:

bob2 posted:

It is a compromise.  The 3-rail scale folks are heading toward the same radius curves - they are paying very close attention to accuracy above the rails, and very soon they will discover that it isn't the center rail that enables them to have sharp curves.

And when they do, their model railroading "Epiphany" will happen, and it will probably go along the lines similar to this:

Coming from a life long involvement in HO, it was during my brief experimentation with 3 rail I learned:

* I was "okay" with the third rail as long as I was running traditional trains in a traditional setting on traditional tubular track.  Mentally I was okay because mentally I was playing with "toy trains". They didn't have to look "real".

* Then I wanted more realism, so I started heading toward "hi-rail"... starting first with the removal of tubular and installing GarGraves track and switches.

* Then I wanted MORE realism and start moving toward scale-sized 3 rail rolling stock.

* Then I wanted MORE realism with the running characteristics I was used to in my decades in quality HO and tried an Atlas SW. 

* The Atlas SW helped a lot, as it ran better than any of the other 3 rail engines (but not as good as my  HO ran), but then I noticed that I was evolving right back to scale modeling... and suddenly I experienced my "Epiphany": That third rail sucked and I could never be happy scale modeling looking at it.

I asked myself "Who am I kidding? I can't be happy with scale trains on three rail track. No way, no how."

So, I returned to 2 rail and soon wound up right back in HO where I started out with on my way to becoming a "serious" modeler back in 1962.

I suspect that many others have, or will, follow the above path if they begin to pursue a path toward more realism.

Exactly!

Russell,  Very true statements. There are a lot of modelers that have the same or similar experiences.

I believe that there were be many more 2-rail layouts if 2-rail models were made that would go around a minimum of a 36 inch radius curve.

 This is technically feasible since Lionel, MTH and 3rd Rail already make all of their trains able to go around O-72 (36 inch radius).  I have a 4-10-2 3rd Rail steam engine that goes around my O-72 curves just fine.  The only difference between my 3-rail engine and the same 2-rail model is that my engine has more blind drivers, larger flanges and a claw coupler on the tender.  

I don't see blind drivers as being a terrible compromise in order to get around a 36 inch radius.  The large flanges wouldn't be needed on 2-rail track.  

The couplers could be designed to swing or pullout on the sharper curves and then return to normal spacing on the straights.  Kadee or someone could design a coupler to do this.  Marklin does this with most of its European passenger cars.  The cars separate on curves and then go back to normal spacing on straights.  Lionel already has a swing coupler design for long intermodal cars and car carriers.  

Most 40 foot 2-rail freight cars with body mounted Kadees will go around 36 inch radius curves just fine.  How do I know?  I run them on my home layout.  Adding a little weight usually gets them through most 3-rail switches without derailing with their  2-rail wheels.  

NH Joe

Brandon Cole posted:

New Haven Joe posted:

The biggest problem with O 2-rail is the large radius needed to run most equipment.  Most of the medium to large O scale equipment needs a minimum of 60 inch radius (O-120) and large switches.  This is the primary reason that O 2-rail is not very popular.   

I am am guessing other manufacturers than MTH need wider radius? MTH big boy will operate on 54" radius. 

Thank you. 

Even scale 89' autoracks will run on 54" curves usings medium-shaft kadees.  Some steam may need larger radii, but hardly any diesels or rolling stock need 60" radius.

Primarily a 3 rail person but I wanted to try 2 rail.  My space limitations were 2 ft x 8 ft, sounds tough doesn't it.  What I did was purchase a 2 inch piece of pink insulation in that dimension.  It fit almost perfectly in the space provided.  I then looked at the small layout scrapbook page for ideas, found one that worked in HO in a 4ft x 1ft space so why not?  Using old Atlas 2 rail switches (7 in all) I was able to create a workable switching layout.  40 foot boxcars and 34 foot covered hoppers are the rule, motive power is either an Atlas sw-9 switcher or and older atlas plymouth switcher (which does not work as well due to motor issues).  Power is a plain old ordinary dc power pack, switches are all getting caboose industries ground throws, the entire layout is a single power block.  The tight radius of the switches pose no real problem because the degree of change is fairly short (22 degrees or less).  The layout looks empty right now but it holds 8 cars plus the loco.  Someday this layout will move to another location and serve one piece of an expanded 2 rail layout, for now it was a low cost entry point to another aspect of the hobby.  

necrails posted:

Primarily a 3 rail person but I wanted to try 2 rail.  My space limitations were 2 ft x 8 ft, sounds tough doesn't it.  What I did was purchase a 2 inch piece of pink insulation in that dimension.  It fit almost perfectly in the space provided.  I then looked at the small layout scrapbook page for ideas, found one that worked in HO in a 4ft x 1ft space so why not?  Using old Atlas 2 rail switches (7 in all) I was able to create a workable switching layout.  40 foot boxcars and 34 foot covered hoppers are the rule, motive power is either an Atlas sw-9 switcher or and older atlas plymouth switcher (which does not work as well due to motor issues).  Power is a plain old ordinary dc power pack, switches are all getting caboose industries ground throws, the entire layout is a single power block.  The tight radius of the switches pose no real problem because the degree of change is fairly short (22 degrees or less).  The layout looks empty right now but it holds 8 cars plus the loco.  Someday this layout will move to another location and serve one piece of an expanded 2 rail layout, for now it was a low cost entry point to another aspect of the hobby.  

Love to see some photos!

Russell,  Very true statements. There are a lot of modelers that have the same or similar experiences.

I didn't have the original post but I did want to add:

I didn't go back to HO as he did, instead I wait and collect O scale 2 rail and bide my time till I will have a real layout in the 'King of Scales'.

I know I shouldn't say it but I have trouble hiding my disdain for HO scale. I know, I know, even John Allen said we can all 'get along' but I tried for YEARS to get into HO and HOn3 and could never do it. It seems to me that a larger scale like O or S is better suited to detail and really SEEING what is there (especially for older eyes) and a smaller scale like N is better suited to the large landscape vistas that are easier to capture in that scale. HO scale is 'middle of the road' in size to me and although it is the favored scale these days (maybe because it IS a compromise between size and space?!?) I will stick to O, thank you very much.

Martin H posted:

Brandon Cole posted:

New Haven Joe posted:

The biggest problem with O 2-rail is the large radius needed to run most equipment.  Most of the medium to large O scale equipment needs a minimum of 60 inch radius (O-120) and large switches.  This is the primary reason that O 2-rail is not very popular.   

I am am guessing other manufacturers than MTH need wider radius? MTH big boy will operate on 54" radius. 

Thank you. 

Even scale 89' autoracks will run on 54" curves usings medium-shaft kadees.  Some steam may need larger radii, but hardly any diesels or rolling stock need 60" radius.

The MTH Big Boy will operate on 54" radius?  54" radius is O-108 in 3-rail.  I thought that all MTH engines would get around an O-72 curve (36" radius) so it should get around a 54 inch radius curve without a problem.  A friend has a 3-rail MTH Triplex that goes around O-72 curves just fine.  

Perhaps the minimum for the 2-rail version of the MTH Big Boy is 54" inch radius.  Does MTH make a 2-rail Big Boy?   A friend has the Lionel Vision Line Big Boy.  It goes around an O-72 curve (36 inch radius) just fine.  

54" radius is a large curve.   The reality is that to operate most big steam in O 2-rail a person will need 60 inch radius (O-120) or larger.  You might be able to get a large engine around a 54 inch radius curve but it probably will not look good.  The same goes for scale passenger cars and autoracks.  

I really think that if manufactures started making all 2-rail equipment so that it could get around 36 inch radius curves, the sales of 2-rail equipment would increase and 2-rail would become much more popular.  

NH Joe

Yes, I do not have space for a loop,  for now I am going with a simple back and forth main to at least run something. Anybody else do this? 

Hey, it's easy to have room for 2-rail if you just narrow the rails a little...

Check out the 0-27 switching layout about half-way down this page, under the heading " Spreading The Word About Small Layouts".   http://www.carendt.com/small-l...age-54-october-2006/

The poster above who suggested 2-rail Hi-Rail has it.  It would be trivial to do - after all, American Flyer did it 3/4 of a century ago.  

Soon the 3-rail scale folks will start looking at what happens below the belt line, and their curves will be the same as 2-rail scale.  As it is, they are getting very picky about detais above the floorboards.  Was it Joe who just discovered that real truck sideframes are well inset from the sides of a car or locomotive?

so is this true of 2 rail (inset truck frames) where as not true for 3 rail, making them more prototypically correct?

bob2 posted:

....Soon the 3-rail scale folks will start looking at what happens below the belt line, and their curves will be the same as 2-rail scale.  As it is, they are getting very picky about detais above the floorboards....

IMO, that's already happening. 

British modellers were mentioned a few posts back. That'll be me, then...

We live in a Country 1/38th the size of the USA, but with 1/6th the population - oh yes we know all about trying to model in small spaces!! In fact this thread has been an interesting read, as it helps me see the "mindset" of most US modellers.

In general, you guys think in terms of modelling a Route, & taking a train along it; we tend to model a Place, & run several trains through it. This works with British outline as our prototype railways run a pretty intense, passenger-oriented service, & our Station designs, with raised platforms etc, take up a fair bit of space to model.

But those of us interested in American trains have found ways to do so along our way of thinking, & involving a certain amount of compromise. None of us have room for multi-deck, basement empires (very few UK houses actually have basements) so we don't often model multi-engine trans-continental freights, unless it's in N gauge, and in relation to the Question of this thread, I'd imagine that if that's what you want to model, then few of you even in the US would have room for 2-rail O.

But the saviour for many of us in the UK has been to follow smaller Railroads, & the Short Line scene in particular. That holds a great fascination for us as we don't have a direct equivalent in the UK - in fact rail freight in such a small Country is quite limited; usually block (unit) trains of bulk goods, steel, coal etc & containers. Most goods go by road.... I digress.

By modelling railroads based on shorter trains and doing just one location, feeding trains from hidden staging, that's how we manage to model US-outline in small spaces. I'm building a "small" 2-rail O layout in my loft (attic) in a space of 17ft by 8ft, using 36in radius curves, but #6 switches. All my diesels up to Atlas SD40 can take the curves. Ironically British O scale trains can't really use such tight curves - the traditional couplings of 3-link shackle and buffers can't cope. Your Railroading Forefathers knew what they were doing when they standardised on buckeye couplers way back when!!

Previously I have built a Switching layout in 12ft x 2ft. Staging was 4ft of that length. Trains were just a loco & 2 cars, but it was great fun and entertained lots of people at two local Model Railway Exhibitions I took it to. I posted a thread about it on here. Search for "Portway Center".

I contend then, that anyone who has room for 3-rail O, has room for 2-rail Scale. You just have to adjust your expectations as to what you actually want to do in that space. As I have said before - a lack of space is merely a challenge to the imagination...!!

SundayShunter

very good article and explanation

Have a liking for Euro engines.  Have a few for DR and DB in G scale (German).  Can only run them around the wall; 9' curves.

 is it correct to call these Euro engines?????

Note on side frames: Real trains run on 4'8 1/2" gauge rails, and typically carbodies are ten feet wide. So, yes, the real ones have sideframes pronouncedly inboard of the car sides.

O Scale runs on 5' gauge, with wheels that, when scaled down, are almost twice as thick as the real ones, so you have at least two things pushing sideframes outward.

Three Rail Scale runs tinplate wheels, which seems to add another 1/8" to maybe 1/4" to sideframe widths. All I know is when I convert 3-rail stuff, I have to make new bolsters to bring the sideframes in.

daylight posted:

SundayShunter

very good article and explanation

Have a liking for Euro engines.  Have a few for DR and DB in G scale (German).  Can only run them around the wall; 9' curves.

 is it correct to call these Euro engines?????

Yes, "Euro engines" will do the European Steam design 'school' was certainly different from the British, where all that visible plumbing would have been hidden if possible, or non-existent anyway. 

The North American school took steam to it's ultimate expression, of course. I don't think anywhere else in the world ran steam locos as big.

In the UK, 4-6-2 & 2-10-0 were the biggest wheel arrangements used, apart from a class of 2-6-0+0-6-2 Garratt engines.