I was viewing Ray Dunakin’s train site and the video he shot of Nevada Northern number 40, a standard gauge Baldwin 4-6-0 that strongly resembles Bachmann’s 10 wheeler, which I’ve been told is based on Tweetsie’s loco. A few years ago I checked the builder’s number of the Nevada loco, 34942, which is the number used by Bachmann’s locos, at least the early versions like my three engines. This makes me wonder if Bachmanns’ product designer, Lee Riley, drew his inspiration or gathered data from the Nevada Northern loco and incorporated it into the final design of the Bachmann 10 wheeler, which is narrow gauge. While you ponder that question, I’ll ask what I really am curious about: except for gauge (36 versus 56-1/2 inches), are the narrow and standard gauge locos the same size (cab, boiler, running gear, etc)? In other words, if you put Tweetsie and Number 40 side by side, would they match?
OK Joe, I’ll take a stab at this. I believe the answer is, it depends on size. Many builder catalogs had smaller locos that could be ordered either in standard or narrow gauge, and were basically the same things except for a wider or narrower frame beneath. This was fine on smaller locos that weren’t trying to maximize the available cross-sectional area they had to keep a locomotive inside for the sake of power. (think, How much can you stuff through that tunnel portal) So as companies were trying to develop massive hauling machines for the prosperous narrow gauge railroads that could afford them, they were forced to deviate from standard design practice. You didn’t have as much room to sink a large diameter boiler between taller narrow gauge drivers. Solution: outside framed locos. Where do you put the massive grate area required to feed air into the huge boiler? Solution: extend the fire box way into the cab and support it all on the trailing truck. What do you do with all the plumbing in the cab once the fire box is taking up the space? Solution: mount the injectors just ahead of the cab on the sides of the boilers. There are lots of other similar compromises that I don’t have time to think of right now I’m sure, so I’ll leave those for others to speak to. Interesting question. (http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-smile.gif)
Ok here is my totally uneducated guess.
My understanding is that Narrow Gauge locos are smaller as a general rule. With normal (if there is such a thing) construction the firebox goes between the wheels over the axles. Wider driver spacing gives a wider firebox. On narrow gauge having such a narrower area to work with meant much smaller fire boxes. This is evidenced in the odd spacing of narrow gauge mogul drivers. By spreading the 2nd and 3rd drivers apart it allows the fire box to be extended below the axles instead of on top of them. But still is a limiting factor. So if you can’t produce as much fire that means you wont need as many fire tubes and therefore a smaller boiler. I could be totally wrong but this is my understanding of it.
Now the CR&N #4 is a much bigger loco than its predecessors because of a different design. They smooshed the 3rd drivers forward until they almost touched the 2nd drivers. This allowed them to build the fire box as wide as the wheel base and also make it deep. As a result they produced much more heat and needed a much bigger boiler. The 1870’s and early 1880’s moguls were small and the 1890’s mogul (#4) was huge in comparison.
Now another consideration was use. Most NG are low budget, small railroads. No need for giant locos. So just for the “cheap” factor I think they were smaller.
But I assume there are at least a few locos that might have been able to be ordered as NG or SG. I would like to know it would be interesting. As a side note many NG locos were converted to SG after the NG popularity waned.
Randy Lehrian Jr. said:
OK Joe, I’ll take a stab at this. I believe the answer is, it depends on size. Many builder catalogs had smaller locos that could be ordered either in standard or narrow gauge, and were basically the same things except for a wider or narrower frame beneath. This was fine on smaller locos that weren’t trying to maximize the available cross-sectional area they had to keep a locomotive inside for the sake of power. (think, How much can you stuff through that tunnel portal) So as companies were trying to develop massive hauling machines for the prosperous narrow gauge railroads that could afford them, they were forced to deviate from standard design practice. You didn’t have as much room to sink a large diameter boiler between taller narrow gauge drivers. Solution: outside framed locos. Where do you put the massive grate area required to feed air into the huge boiler? Solution: extend the fire box way into the cab and support it all on the trailing truck. What do you do with all the plumbing in the cab once the fire box is taking up the space? Solution: mount the injectors just ahead of the cab on the sides of the boilers. There are lots of other similar compromises that I don’t have time to think of right now I’m sure, so I’ll leave those for others to speak to. Interesting question. (http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-smile.gif)
Randy a case in point for your illustration minus the trailing truck.
CR&N #4 photo courtesy of Narrow Gauge Chaos/ Robert Pearson Collection
This locomotive has a giant fire box aft of the rear drivers and as such the boiler extends all the way to the rear of the cab. Notice the Eames brake injector out side the cab. This loco has a 60" boiler huge compared to what came before it. It was built by Baldwin in 1888 and is NG. being behind the drivers meant no restriction on width or depth caused by frame, drivers, or axle. Baldwin eventually used this design in SG big locos.
The D&RG Locos had fairly large boilers and looked “top heavy and squat” for that reason. Of course they were built with the outside frame and small drivers, so there was a lot more room above the drivers, and the firebox overhung to the rear of the driver frame.They were essentially Large Locos on small loco frames. I think the relatively larger NG Locos came a lot later than the engines mentioned above.
Andrew,
As an anomaly the D&RG has all kinds of interesting stuff due to their longevity. I would like to here from Dave on this. Also the EBT was another longer lived larger NG operation. Kevin Strong maybe able to tells us more.
You also note the outside frame and smaller drivers. I have noticed the that but never put two and two together. In SG there were some very top heavy looking locos due to getting those big fire boxes over the axles. With smaller drivers you can lower the center of gravity and have better clearance for the boiler but you would still have the axles to contend with. That would still make it top heavy looking. And since high speeds weren’t a concern I would think the small drivers would present no problem.
When I model I tend to be student of the subject and I looked at a lot of photos of locomotives and as many of the real thing as I could and one thing that stands out to me is how innovative people can be when they need to be. There are some pretry radical fire box designs to fit the limited space and get the most out of it.
CR&N #4 is quite a handsome loco Devon. She certainly caries a lot of Baldwin characteristics about her. I’m glad you up loaded that photo since what good is any thread without pictures? With that in mind I’ll share a few of the EBT’s locomotives that inspired some of my comment’s in my earlier post. (except about the out side framing, you won’t find that on the EBT )
First is #11 an 2-6-2 Prarie type built in 1908, total tractive effort was 16,00 lbs. She was the first Locomotive the railroad had that employed a trailing truck and allowed for the much larger fire box behind the drivers.
#11 was very well received and the design was scaled up adding one more set of driver for a 2-8-2 Mikado type that became very successful on the EBT. The design was so successful that they ordered 5 more for a total of 6 Mikados. Pictured below is #18 the largest built in 1920 with 30,600 lbs of tractive effort. Notice the massive fire box supported by that large trailing truck. I’ve been in the cab of on of these monsters, there’s only about a foot to stand in between the side of the boiler/firebox and cab side. Not much room at all and it must have been very hot in the summer!
Generally speaking, narrow gauge “loading gauge” (overall size) is much less than that of standard gauge. The vast majority of narrow gauge equipment fell right around 8’ wide and 11 - 12’ tall. By contrast, standard gauge “loading gauge” is on the order of 10’ wide by 14’ - 15’ tall. Proportionally, however, you would find similarities between standard and narrow gauge equipment. There’s a Maryland & Pennsylvania standard gauge locomotive that looks all the world like the ET&WNC narrow gauge 10-wheeler. When Pressed Steel Co. designed the EBT’s steel hoppers, they took the plans for the standard gauge hoppers they were making and adapted them for the smaller size of the narrow gauge.
There are exceptions, of course. The D&RGW’s outside-frame locos were rather wide, with the Ks hitting in excess of 10’ at their widest. (The K-37s were built with the boiler, cab, and tender of a standard-gauge C-41.) The Uintah 2-6-6-2s and the White Pass Alcos likewise exceeded 10’ wide. But even with those wider locomotives, the rolling stock pulled behind stayed pretty much the same as it always had been. The locomotives pretty much just dwarfed it. As Andrew said, these came about in the 1920s or later, though, after most of the narrow gauge lines were either gone or not remotely close to being in a position to contemplate new equipment.
Later,
K
So if it’s true that, “the rolling stock pulled behind stayed pretty much the same as it always had been. The locomotives pretty much just dwarfed it.,” as Kevin says, then you can use a 1:20.3 loco with 1:22.5 rolling stock, ya?
But back to my question: Are the narrow gauge 10-wheelers that supposedly served as the prototype for Bachmann’s Annies, the same size as the standard-gauge Nevada loco shown on Ray Dunakin’s website? Just wondering…
On the EBT mikados I am wondering if they weren’t designed using much of the CR&N #4. After all the EBT must have liked the design because they had one built and bought the #4. The EBT #5 and #9. Now correct me if I am wrong but didn’t the mikados come after. I think Kevin told me that the mikado drivers are the same as well as I think they share the #4s fire box design but being bigger yet would need the trailing truck. Seems to me the mikado is just an evolution.
As time went on sure the NG locos got bigger but so where SG bigger.
Yes, but I don’t think in the context you’re thinking. Commercially-available 1:22.5 rolling stock (particularly freight equipment) do scale comparably to prototypes when measured with a 1:20.3 scale ruler. For example, the LGB box car (reasonably accurate in 1:22.5 for the Southern Pacific prototype on which its based, though a touch short if I recall) scales out almost spot on for a Chicago & Northwestern (narrow gauge) box car when measured in 1:20.3. Likewise, the old Delton/Aristo wood hopper cars (1:24) scale out well for early wood hoppers when measured in 1:20.3.
No, they wouldn’t be the same size. It would be roughly the same proportions, but it would be about 20% smaller. The standard gauge loco would be about 10’ wide and 14’ tall, whereas the narrow gauge loco would be about 8’ wide and 12’ tall. (Roughly. If I were home, I could get specific sizes.)
Later,
K
Also, it probably should be mentioned that any given wheel arrangement could be, and usually was, used on locos of different sizes even in the same gauge.
Ray Dunakin said:
Also, it probably should be mentioned that any given wheel arrangement could be, and usually was, used on locos of different sizes even in the same gauge.
Ray,
Thanks for mentioning that because it is very true. My loves are moguls, the 2-6-0 arraignment, (actually my true love are the American 4-4-0) and in moguls there is a wide range of sizes even in the 3’ gauge. In my own railroad the difference is huge.
This is the same type of locomotive as the CR&N #3. It is a baby compared to the CR&N #4.
It weighs 40,000 pounds on the drivers and the #4 weighs 74,000 pounds on the drivers. #3 boiler has a 38" diameter the #4 is 54" (I said 60" earlier I was mistaken) 40" drivers and 48" drivers respectively, 12" dia X 18" stroke cylinders vs 16X24, Total wheel base engine and tender is 35’ compared to 45’ of the #4. I don’t know the exact tractive effort of the #3 but the similar sized #1 was a little over 8,000 lbs compared to the #4s 14,000 pounds.
So there is considerable difference in same gauge same wheel arraignment locos.
Thanks for pointing that out Ray.