This information has, of course, been presented many times before, but I had a request from a Forum member for a distilled version.   Here's what I told him:

Sure!  Glad to help.  First thing:  Scale and gauge are two different things entirely.  All O gauge equipment runs on track 1.25" in gauge, but not all of the equipment is the same size...

===

O scale (1:48):  Pretty simple and straightforward. 1/4" = 1 foot.
Q scale (1:43):  Ever wonder why Corgi, Dinky and other European diecast cars are 1:43 scale instead of 1:48?  It's because, in 1:48 scale, 1.25" = 5 foot gauge.  If you bump that up to 1:43 scale, the track drops down to 4' 8 1/2" or prototype gauge.  17/64" = 1 foot.
Traditional (O-27):  Here, things start getting a little hinky.  Traditional scale cars are shrunk to work on the tighter radii of O-27 track.  In fact, a lot of S gauge (1:64) modelers will put American Flyer trucks under Lionel traditional size boxcars, et cetera, as they're about the right size and are much cheaper than AF rolling stock.
Semi-scale:  Sorta halfway between pure O scale and traditional.  Lionel 6464 boxcars are an example of this, and clock in at approximately 1:56 scale.
You'll find similar phenomena with HO/OO and the variety of scales in G gauge.
Hope this helps!
Mitch
EDIT:
@Bob posted:

Mitch,

Good discussion except that Q scale is actually 1:45 and not 1:43 (4 feet 8.5 inches divided by 45 is 1.25 inches).  Lionel's original U.P M10000 passenger train in 1934 was in 1:45 scale and I think the Hiawatha might be the same.  "European O-scale" as used in places like France and Germany is 1:45.

The 1:43 stuff comes from "British O-scale" which is 7 mm to the foot or 1:43.5 scale.  Our 1.25" gauge track is thus used by 3 different scales.

I sit corrected!

Last edited by M. Mitchell Marmel
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Thanks Mitch! Reading my mind... I appreciate ya.

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Mitch,

Good discussion except that Q scale is actually 1:45 and not 1:43 (4 feet 8.5 inches divided by 45 is 1.25 inches).  Lionel's original U.P M10000 passenger train in 1934 was in 1:45 scale and I think the Hiawatha might be the same.  "European O-scale" as used in places like France and Germany is 1:45.

The 1:43 stuff comes from "British O-scale" which is 7 mm to the foot or 1:43.5 scale.  Our 1.25" gauge track is thus used by 3 different scales.

Well, then there's the fact our track is not true 1:48 scale.  To get that you have to go Proto48.  O gauge track at 1:48 scales out to 5' instead of the correct US Standard Gauge of 4' 8 1/2".  Proto48 is certainly very cool, and my hats off to those that do it.  I am enjoying following Sarah's work on this in the 2 Rail forum.  However as a hobby it's certainly a niche, within a niche, within a niche, within a niche.

@Bob posted:

Mitch,

Good discussion except that Q scale is actually 1:45 and not 1:43 (4 feet 8.5 inches divided by 45 is 1.25 inches).  Lionel's original U.P M10000 passenger train in 1934 was in 1:45 scale and I think the Hiawatha might be the same.  "European O-scale" as used in places like France and Germany is 1:45.

The 1:43 stuff comes from "British O-scale" which is 7 mm to the foot or 1:43.5 scale.  Our 1.25" gauge track is thus used by 3 different scales.

I sit corrected!  Thanks!

Mitch

The definitions of scale and gauge are as follows:

Scale is the ratio of the size of a model compared to the full-sized item. For O scale, the numbers are 1 and 48, so the ratio is 1:48 or 1/48, and the actual item is 48 times as large as the model.

Gauge is the distance between the inner edges of the track rails. On a standard gauge railroad in the United States, that distance is 4-feet 8-1/2 inches (56-1/2 inches). For American O gauge track (say Lionel), the gauge is 1.25 inches.

For O scale, the exact track gauge is (56-1/2 inches divided by 48) 1.1771 inches. In the United States, American O scale and O gauge track approximate this exact value using 1.25 inches instead. Proto-48 models are built to the exact track gauge. Three-rail O gauge models are built to a 1.25-inch track gauge which is equivalent to 5-feet at full scale.

MELGAR

Last edited by MELGAR

The whole history of the 3 rail train hobby is one of "muddy waters" as far as terminology goes. Lionel trains have, for most of their history, been toy trains, with the (what we now call) the traditional line up(O gauge and 027) being the backbone of the hobby. Sure, you had products like the NW2 and the GP9 that had body shells that were pretty close to scale proportions, but lacking the body details many are now accustomed to. And then there's the more basic chassis frame on those older models.

If you go to YouTube, you can find videos of layouts that feature "traditional" trains, where folks label them as "0 Scale." And then there are videos of layouts where the trains are the newer scale types, which get labeled as "0 gauge."

And then consider the name "Lionel." It's a company, but it's also such an iconic name, that it has come to mean the entire 3-rail hobby. We in the hobby know all about MTH, Weaver, RMT, Atlas, 3rd Rail, K-Line and all the other companies that have come and gone. But to most people, it's all Lionel.

Then there's the term "hi-rail" which has been around for decades. By my understanding, that term was something of a derision in reference to the height of the 3-rail track on a layout, that in every other aspect strives for realism, albeit with toy trains. Over the years there have been some amazing hi-rail layouts that featured tubular track and strictly 027 types of trains. Frank53's layout comes to mind, as does another member here, gandydancer1950. So the term "hi-rail" is certainly NOT exclusive to true scale proportioned trains only. I think where the "hi-rail" term got high jacked is when Weaver was labeling their trains as such to indicate the difference between 2-rail true 0 scale and 3-rail wheel sets with lobster claw couplers.

Or how about the iconic Plasticville buildings: A cross between 0 and S scales. A brilliant idea for sure, to increase market share and sales. And as with Menards, buildings with smaller footprints, means more people with smaller sized layouts, can purchase them. But the waters get muddy again when you're striving for precise scale realism on your layout. I won't even mention the block signals, crossing gates, the operating gateman or newsstand, which are all Lionel and all marketed for 0 gauge trains and yet even by the most forgiving liberal of standards, are hardly 0 scale.

Again, if you look on YouTube, you can also find layouts that feature nothing but recent production, high end scale trains on a layout that is hardly hi-rail at all, but much more of a postwar traditional layout. Instead of a green painted board, it's green felt or indoor/outdoor carpeting. And instead of tubular track, it's FasTrack.

Jerry Calabrese once said, when he was CEO at Lionel, that the company could ill-afford to ignore any one segment of this overall fragmented 3-rail market. And that probably still holds very true. To this time, it is the traditional line of starter sets that pays the bills and keeps Lionel in business. Lionel could drop the high end scale line and it would hurt them, but not put them out of business. But the company couldn't survive without the starter set product line up. That might in part, have something to do with MTH's money difficulties, since they never had the market share of starter set sales the way Lionel always has.

The truth is, there is NO one right or wrong way to participate in, and enjoy the hobby. It's all the terminology that makes it confusing sometimes. And despite the impressions one could get from looking at current train catalogs, the "traditional" side of the is hardly dead. Those trains were produced in huge production runs. There was one single year alone, where Lionel made over 182,000 operating 027 milk cars. Then in the late 1980's through the 1990's I think people were overbuying trains, in speculation that the trains could only increase in value. This of course, leads to a skewed impression that the hobby market was bigger than it really was.

The overall market is undoubtedly shrinking. And it is more diverse than ever. All the 3-rail train companies have stated today the emphasis is on variety and not quantity of production runs. Which by the way, has a lot to do with increasing prices: Smaller production runs equals less opportunity to spread out tooling costs. The smaller marketplace and the increasing diversity of interests within that marketplace certainly also have an effect. We've been spoiled by the product offerings over the past couple decades, which I think is going to change.

At one time, you could say "Lionel Trains" and it meant one thing: Toy trains. Now, you have to be a little more specific as to what you are looking for. To some, "Lionel Trains" means scale proportions and Legacy. For others, it still means as it always has. To some, a Lionel box car will forever be the iconic 6464 proportioned box car. For others, the thought of that will make them cringe. And yet they're all box cars and they're all Lionel. Even the "Scout" boxcars are still boxcars and still Lionel. So when you see Lionel boxcars for sale, you need to see some photos and/or read the fine print today.

Like I said, there's no one way to enjoy the hobby. It's all a matter of preference. But the terminology (and diversity of products) can be confusing sometimes, especially for new comers to the hobby.

'

Oh, ouch!

I did not know Minton Cronkhite, but flew airplanes with his kid.  I started in O Scale in 1955.  I do not model in Q gauge, which is Minton Cronkhite's invention to sort of match 1/4"scale to a track gauge, but I started in a similar vein, with 1 1/8" gauge, 1/4" Scale.

I also model in 17/64" Scale, O Gauge, extensively.  I am willing to bet that I am, right now, this hobby's foremost practitioner of 17/64 scale.

O gauge is 1 1/4" track width. Period.

Q gauge is 1 3/16" track gauge. period.

1/4" scale (1:48) models are appropriate for Q gauge.

There is no such thing as Q Scale.  If Q Scale were to be defined as 1:45, or 17/64, or some larger scale in that vicinity, it would be a serious mis-match for Q Gauge.

As for the rest of it, you guys have every right to re-define "Semi-Scale."  Just recall that in 1940, Lionel defined it as absolute scale cars on tinplate trucks.  Not my concern.

Hum!  I had read Q scale as being 17/64ths somewheres along the line, but I defer to the experts.

(Parenthetically, a chum of mine wrote a comedy radio script with two bungling handymen sending in 30,000 boxtops for a Q scale model trolley which turned out to be 1:1 scale, but that's neither here nor there.)

Mitch

Good information all.  But now, for something completely different, here's some food for thought................

In the track gauge department, I've got good news.  And I've got bad news.

In the good news department, if you run your 1/48 scale trains on 1-1/4" gauge track, then your trains are to scale even though your track is not (5'-0" between the rails).  Huh?

And the bad news - if you run your 1/48 proto-scale trains on 1-3/16" gauge track, then while your track is to scale (or pretty darn close to the scale 4'-8 1/2" track gauge), while your trains are not.

And more bad news for the 17/64" modelers, while your 1-1/4" gauge track is to scale, your trains are not.  For the exact same reason as the proto-scalers running on 1-3/16" gauge track.

How's that, you ask?  Because our models MUST have some sort of tolerance to be able to run on our miniature track (with our substandard curve radii).  And 1/16" ~ 3/32" tolerance or so, seems to be a pretty good tolerance to shoot for in O-scale/O-gauge.  Which translates into 3" ~ 4-1/2" full size tolerance measurement.  And I guarantee, the full-size WHEEL FLANGE GAUGES on full size locomotives and train cars are nowhere near 3" to 4-1/2" LESS than the full size track gauges.  Full size train wheel gauges (4'-7 1/2") are about one inch LESS than the full size track gauge (about .0208" less in 1/48 scale).  And at .0208" less, our model trains would NEVER be able to successfully run on the sub-standard curves that most of us O-gaugers/O-scalers have to use with our models, due to physical space constraints.

Doubtful?  Measure the wheel flange gauges on any of your standard O-gauge or O-scale locos or rolling stock, and what do you get?  About 1-5/32" to 1-3/16" across the wheel flanges.  Which translates to about 4'-7 1/2" full size measurement.  Which means your train wheels are gauged to scale!

So there ya' go.  In my opinion, all those modeling Proto 1/48 or 17/64" scale for all these years have probably been worshiping a false deity all this time.

As for me, I enjoy the simpler things in life, like running O-gauge trains on 1-1/4" gauge track.  Life's too short to fret over 1/16" or so, as far as I'm concerned.

How about the rivets on the motive and rolling stock?

Are they correct scale?

Well, here are a few nuggets for consideration.

Brian talks about the term "hi-rail" as most likely coming from the height of tinplate track. This is what I always thought. Then recently I unearthed and thumbed through a copy of 'The Model Railroad Book" by Warren Morgan. This was published in 1953.

In the book ( page 19) Commander Morgan talks about the origin of the term. Here is the gist:

In the late 1930s, while building one of the first "hi-rail" layouts, his sons decided they needed a password for their family train club. Pop suggested "Hi, Rails!" because railroad buffs in the Navy were called "rails". In 1940 this layout was featured in Model Builder. Dick Robbins of Polk Model Craft Hobbies in NYC liked the article and was interested in promoting the use of "tinplate" on realistic model railroads and sold Charlie Penn, editor of Model Craftsman, on the idea of a series of articles on mixing scale and tinplate and they needed a name. Mr. Morgan then suggested "Hi, Rails" and the term caught on and became "hi-rail". Make of this what you will, but since the story of the origin was published in 1953 and Warren Morgan was a respected writer on the hobby, it has a certain plausibility.

The other little nugget is something I have always found interesting. Lionel, in its early marketing, coined the phrase "Standard of the World". They then reinforced this by calling their largest trains "standard gauge". There was of course no such thing as a standard gauge in toy trains at that time. There was however a "standard gauge" in full size railroading and that was 4' 8 1/2". ( How that happened is a discussion for another time.) The two uses of "standard gauge" of course have no connection, but this must occasionally be confusing to newcomers to the hobby.

Cronkhite used Q Gauge for his track and trains. His buildings, i have a few, are close to 1/48 scale and some are sized for forced perspective areas on his Chicago  Museum of Science and Industry layout, now retired. So scale is difficult to determine for those.

I try to keep it simple O gauge means 1 1/4" between the outside rails.

3 scales run on it:

semi-scale = o-31

and true scale= true scale.

There are a lot of shades in between but this helps to keep it simple and organized in my head.

Strange way of looking at it.

O Scale and O Gauge are often thought of as synonymous.  Lionel has its own terms, none of which match scale and gauge.

While Paul's analysis may be strictly true - just as we do not use 1:48 Diesel engines to power our traction motors - models are compromises.

Most of us differentiate "scale" as having to do with overall dimensions and details, not flange clearance or whether our brakes actuate with air pressure.

If you really want to keep your wits about you when discussing scale and gauge, use the common nomenclature for gauge (Z, TT, N, HO, OO, S, Q, O, G) and use inch per foot (or mm per foot) for the scale.  And please - all Q-gauge models were 1/4" to the foot, or 1:48.  All of them.

Then, use Lionel's current nomenclature when discussing undersize Lionel, and MTH nomenclature when discussing MTH.  As far as I can tell, nobody else is making undersize models for oversize track.  This is a special area.

@Bob posted:

Mitch,

Good discussion except that Q scale is actually 1:45 and not 1:43 (4 feet 8.5 inches divided by 45 is 1.25 inches).  Lionel's original U.P M10000 passenger train in 1934 was in 1:45 scale and I think the Hiawatha might be the same.  "European O-scale" as used in places like France and Germany is 1:45.

The 1:43 stuff comes from "British O-scale" which is 7 mm to the foot or 1:43.5 scale.  Our 1.25" gauge track is thus used by 3 different scales.

Bob:

One day when this current situation passes, I have a small group of people (6 or 7) that I would love to see your layout--my favorite outside the Glacier Line :-)--in person.

Hope you and the family are doing well. :-)

Manufacturers of toy trains and accessories decided what scale and gauge means. Unless you make your own 1/48th models you are subject to what's made by others.

For the longest time Lionel decided for us what is scale. Other Manufacturers have come along to change that perception.

I make 1/48th scale models on my printers and cutters but I recognize that I too am subject to the scales of others whenever I purchase from another maker.

I respect anyone who can reject anything other than 1/48 scale items like trains, track and other pieces on their layout.  Because I can't!

And the bad news - if you run your 1/48 proto-scale trains on 1-3/16" gauge track, then while your track is to scale (or pretty darn close to the scale 4'-8 1/2" track gauge), while your trains are not.

Sorry, but not sure I follow this logic.  Scale is the overall dimensions in relation to the real world counterpart.  Fidelity would be how accurate something is to the real world counterpart.  Tolerance has nothing to do with scale.

Even the most accurate scale models ever made are not 100% to scale.

Even the most accurate scale models ever made are not 100% to scale.

Well only for those who don't have a shrink raygun or a 100% accurate model to work from.

If you're saying we can't model the dust, well again ok!  Accuracy in this way becomes very subjective.

Another way to look at modeling accuracy is to say that at this scale, you cannot see a 1/8" diameter bolt, so why to I need to model that to be 100% accurate.

Then of corse there’s narrow gauge usually associated with the 3 ft gauge roads than in CO and NM although narrow gauge trains ran in the east too.   On3 would be 1/48 proportioned trains (aka O scale) running on 3ft gauge track (3/4 “ in O scale).  Bachmann muddied the narrow gauge waters by offering On30 trains which are O scale trains that run on 30” gauge track.

Back to our three rail hobby, the relaxed approach between scale and gauge is an attraction for me, not a frustration.  I appreciate what the 3RS guys do, although that’s not for me.  I likewise appreciate tin plate and post war, but those are not fo me either.  My hi rail sweet spot is in the middle -mostly semi-scale stuff with some scale equipment mixed in. The fact that my track has 3 rails and the gauge is not strictly O scale is fine with me.

I like wise appreciate that the full spectrum of preferences is welcome on.  We have a great hobby

@AlanRail posted:

Even the most accurate scale models ever made are not 100% to scale.

Well only for those who don't have a shrink raygun or a 100% accurate model to work from.

If you're saying we can't model the dust, well again ok!  Accuracy in this way becomes very subjective.

Another way to look at modeling accuracy is to say that at this scale, you cannot see a 1/8" diameter bolt, so why to I need to model that to be 100% accurate.

Oh I agree with you 100%.  I just didn't understand where mixed freight is coming from.  Like I said scale in modeling has always been dimensional, fidelity is accuracy and where rivet counters come in.

I participate in the scale side of RC Trucks, there are models that in the right setting look 100% real, it take careful to review to pick out what's not there and figure out it's not the real thing.

After all, per your ray gun comment, we can't shrink the atoms.

While all hobbyists appreciate the technical aspects of their respective hobbies, most of us newbies are trying to determine what the effect is in the real world - i.e., what it means for me on my setup.

I'll use myself as an example. I had HO Scale trains when I was a kid (or rather my father did). I decided to get a train for around the tree. I had see many at Disney but decided to visit the Lionel website. I chose MICKEY'S HOLIDAY TO REMEMBER" DISNEY CHRISTMAS LIONCHIEF TRAIN SET. I can't even remember why other than I wanted a Mickey set and didn't want a battery powered set. Maybe the working smoke or something.

Anyways, that was last year. So this year I wanted to expand and do some more stuff. So I start looking at the Lionel website. Ok, it says my set is O-Gauge. So You look at their website at the "Get Started" Page. They have a big graphic showing the different gauges. They don't have anything about O-Scale there. So then you scroll down and see a button to learn more about gauges. You click there and get taken to this page. You go all the way down to "O-Gauge." Its not till the end of the paragraph you get to this line:

"O-Gauge is divided into two categories: Traditional O-Gauge and O Scale."

So now that's the first time you see there is this thing called O Scale. Now you have to read fully to appreciate the differences which really are two main things:

• Higher-end products
• Larger than Traditional O-gauge products since they are more true to 1:48 scale proportions

So ok...Well how much larger? It doesn't really say. Can you use O-Scale with O-Gauge or will it look weird.

Add to this little fact. You peruse Lionel's catalog. Now I see they have an O Scale section and an O Gauge section. No problem, I just avoid O Scale. But then there are special sections (Christmas) that have both mixed in. I see something I really like. I see the CHRISTMAS LEGACY ES44AC #1224. I really want it. I miss that the catalog says O Scale and I look up the product SKU on their website. It's product SKU: 2033571. Oh, btw, they have different road numbers for this locomotive with different SKUs. So one might think the different road numbers are different gauges. Nope. But when you go to the link for either one what does Lionel have for the Gauge:  O Gauge. No mention that its O Scale. You sorta figure that out when you realize the minimum curve is O52 and then look at the length of the thing.

And that's before we even start discussing whether I can use MTH or some other brand in conjunction with my O Gauge setup.

@Lennyski posted:

...

3 scales run on it:

semi-scale = o-31

and true scale= true scale.

Nobody has mentioned yet that two prominent manufacturers have marketed 3/16" scale trains running on O gauge track, adding at least one more scale, to make 4.

But wasn't that American Flyer?

One probably needs to isolate the different toy train makers' nomenclature setups.

I know very little about such nomencature, but isn't "Traditional Size" roughly the same as "Rail King?"

Once you depart from the term "scale" you cannot really depend on products having a fixed percentage of scale size - for example, "Railking Scale" is often true 1/4" to the foot, but their other offerings may be closer to, say, O-27, whatever scale that is.

Fascinating.

@bob2 posted:

But wasn't that American Flyer?

Yes, and Marx.

@bob2 posted:
I know very little about such nomencature, but isn't "Traditional Size" roughly the same as "Rail King?"  ...example, "Railking Scale" is often true 1/4" to the foot, but their other offerings may be closer to, say, O-27, whatever scale that is.

That was a problem w/ the old MTH company. So many of the RailKing products were sized to true O scale, and they often didn't look quite right in with 6464 type/sized rolling stock. What made them belong in the RailKing line was very simple decorating and less detail molded in and/or attached.

@Aaron G. posted:

While all hobbyists appreciate the technical aspects of their respective hobbies, most of us newbies are trying to determine what the effect is in the real world - i.e., what it means for me on my setup.

I'll use myself as an example. I had HO Scale trains when I was a kid (or rather my father did). I decided to get a train for around the tree. I had see many at Disney but decided to visit the Lionel website. I chose MICKEY'S HOLIDAY TO REMEMBER" DISNEY CHRISTMAS LIONCHIEF TRAIN SET. I can't even remember why other than I wanted a Mickey set and didn't want a battery powered set. Maybe the working smoke or something.

Anyways, that was last year. So this year I wanted to expand and do some more stuff. So I start looking at the Lionel website. Ok, it says my set is O-Gauge. So You look at their website at the "Get Started" Page. They have a big graphic showing the different gauges. They don't have anything about O-Scale there. So then you scroll down and see a button to learn more about gauges. You click there and get taken to this page. You go all the way down to "O-Gauge." Its not till the end of the paragraph you get to this line:

"O-Gauge is divided into two categories: Traditional O-Gauge and O Scale."

So now that's the first time you see there is this thing called O Scale. Now you have to read fully to appreciate the differences which really are two main things:

• Higher-end products
• Larger than Traditional O-gauge products since they are more true to 1:48 scale proportions

So ok...Well how much larger? It doesn't really say. Can you use O-Scale with O-Gauge or will it look weird.

Add to this little fact. You peruse Lionel's catalog. Now I see they have an O Scale section and an O Gauge section. No problem, I just avoid O Scale. But then there are special sections (Christmas) that have both mixed in. I see something I really like. I see the CHRISTMAS LEGACY ES44AC #1224. I really want it. I miss that the catalog says O Scale and I look up the product SKU on their website. It's product SKU: 2033571. Oh, btw, they have different road numbers for this locomotive with different SKUs. So one might think the different road numbers are different gauges. Nope. But when you go to the link for either one what does Lionel have for the Gauge:  O Gauge. No mention that its O Scale. You sorta figure that out when you realize the minimum curve is O52 and then look at the length of the thing.

And that's before we even start discussing whether I can use MTH or some other brand in conjunction with my O Gauge setup.

"O-Gauge" trains are any trains that run on track that is gauged at 1-1/4" between the rails.  Since "O-Gauge" trains originally started out as toy trains, the "scale"of O-gauge trains can be all over the place.  Most commonly it ranges anywhere from 1/48 (1/4" = 1'-0") scale to 1/64 scale (3/16" = 1'-0").

Virtually all 3-rail O-gauge trains, with their "lobster claw" couplers can be run together, regardless of their actual scale or manufacturer.  Whether or not the various sizes look good together is up to the individual.  Generally, toy train operators aren't too concerned with mixing scales on the layouts, while folks with more of an eye for prototype fidelity tend to run like sizes together.

Believe it or not, your Mickey's Holiday To Remember 4-4-0 American-style General locomotive with wood tender is actually larger than 1/48 scale!   Not sure how much larger, I've never taken the time to do some measuring, calculating, and guestimating at its approximate scale, but it is definitely larger than 1/48.  The boxcar appears to be a traditional-sized car, somewhere between 1/48 and 1/55 scale.  The gondola and caboose maybe about the same?

Your Christmas Legacy ES44AC is listed as "O-Gauge" because it will run on O-gauge track.  It may or may not be built to a true 1/48 scale.  I don't own one, so I don't know.  But it still may fit in just fine, looks-wise, with your current stuff.  It all depends on what you think.

They say a picture is worth 1000 words, so I like to show this photo for anyone like Phil55 who is (rightfully) confused by all this.  These boxcars are all made to run on O-GAUGE track, but are obviously vastly different scales.

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TrainsRMe,

Are the multiple model cars in your picture all supposed to be "representing" (I hesitate to use the word modeling) the same size original car (e.g. 40' boxcar)?  If so, why don't you provide a list of the manufacturers (in order) from top to bottom just for funnsies?  I'd sure like to know who makes the largest and the smallest.

Chuck

"O-Gauge" trains are any trains that run on track that is gauged at 1-1/4" between the rails.  Since "O-Gauge" trains originally started out as toy trains, the "scale"of O-gauge trains can be all over the place.  Most commonly it ranges anywhere from 1/48 (1/4" = 1'-0") scale to 1/64 scale (3/16" = 1'-0").

Virtually all 3-rail O-gauge trains, with their "lobster claw" couplers can be run together, regardless of their actual scale or manufacturer.  Whether or not the various sizes look good together is up to the individual.  Generally, toy train operators aren't too concerned with mixing scales on the layouts, while folks with more of an eye for prototype fidelity tend to run like sizes together.

Believe it or not, your Mickey's Holiday To Remember 4-4-0 American-style General locomotive with wood tender is actually larger than 1/48 scale!   Not sure how much larger, I've never taken the time to do some measuring, calculating, and guestimating at its approximate scale, but it is definitely larger than 1/48.  The boxcar appears to be a traditional-sized car, somewhere between 1/48 and 1/55 scale.  The gondola and caboose maybe about the same?

Your Christmas Legacy ES44AC is listed as "O-Gauge" because it will run on O-gauge track.  It may or may not be built to a true 1/48 scale.  I don't own one, so I don't know.  But it still may fit in just fine, looks-wise, with your current stuff.  It all depends on what you think.

Ok, I get that it says O Gauge because it will run on O Gauge track. But that tells you very little given how I just showed that they divide O Gauge into two categories. Look at this for example: CHRISTMAS OPERATING FREIGHT TERMINAL SKU: 6-37965. That has the Scale listed as "traditional." That's at least a bit more helpful.

I did notice this year that my Disney Berkshire O Gauge seems smaller than my Mickey's Holiday to Remember 4-4-0. It's much, much heavier than the 4-4-0 too. The Gondola appears to me to be Lionel's traditional O Gauge. I measured the length and height and it is the same as my other gondola rolling stock I purchased (LIONELVILLE TREE TRANSPORT O27 GONDOLA WITH CHRISTMAS TREES SKU: 6-26061). Which makes sense because Lionel is just taking the same Gondola and putting various paint jobs on them. It wouldn't make sense to have more than two sizes in O Gauge.

The ES44AC is very long. Specs say 052 minimum curve. I'm running some 031 curve and definitely will be using 036. I still think it would likely be ok in terms of derailing since I'm running straight sections in the middle of my corner curves. But I wouldn't want to purchase a made to order piece then figure out after I got it that it looks terrible on my setup. That's the biggest problem. If I could merely order it on amazon, put in on the track and return it no questions asked, then we wouldn't be having this conversation.

@TrainsRMe posted:

They say a picture is worth 1000 words, so I like to show this photo for anyone like Phil55 who is (rightfully) confused by all this.  These boxcars are all made to run on O-GAUGE track, but are obviously vastly different scales.

It's worth a thousand words, sure. But a few words about which is which would be more helpful.

Okay, you two - I didn't think the manufacturers would be relevant to this discussion.  I no longer have the cars, but but here goes to the best of my recollection.  Top to bottom:  Weaver, unmarked, Lionel, Lionel, Lionel MPC.  The bottom picture shows a Weaver and a Marx.  They all are 40' types - I had no modern styles.

Here is another view of the top five cars.

Images (1)