I just aquired some Intermountain cars of this nature and am trying to find out when they were first designed, I can find build dates but not design dates and like so many thing railroad related, designs can go back quite far with only a prototype built untill a company accually starts to produce them.
I think you're referring to the various AAR boxcars designs, first designed and produced in the 1920s, but with the 1932 AAR design being considered the definitive early version despite thousands of similar cars already produced.
A brief hist can be found here: http://www.atlasrr.com/HOFreight/ho1932boxcar1.htm
And here: http://steamerafreightcars.com/prototype/frtcars/1932aramain.html
Tony Thompson goes a little more in-depth here: http://modelingthesp.blogspot.com/2012/12/small-modeling-project-1932-ara-box-car.html
Mike Lehman
Urbana, IL
The term "12 PANEL BOXCARS" sorta threw me, as the 1923 ARA, 1932 AAR boxcar, the CPR "Minibox" and the AAR 1937, and "improved" 1937 cars are all 10-panel cars.
The first mention of 12-panel cars that a quick search yielded was in Ted Culotta's excellent "Steam Era Freight Cars Reference Manual", showing Southern Pacific and T&NO 12-panel cars based on the AAR Postwar 10'0" inside height box car design.Those cars were built in 1946, by both Pullman-Standard and Pressed Steel Car Co.It would appear, from this book, at least, that the majority of these post-war cars were of the 10-panel design, not the 12-panel variation
A search of those two firms might yield information on the origin of that particular version, and perhaps a list of the roads which actually used it.
Wayne
Since the OP mentioned I-M cars, I suspect these are GN prototypes...
Modeling BNSF and Milwaukee Road in SW Wisconsin
I know of the 1946 build date but ussually the design date is earlier, sometimes much earlier.
jrbernier Since the OP mentioned I-M cars, I suspect these are GN prototypes...
I agree, although most of the standard boxcar types were built with 12 panel sides none are offered as a standard car to be purchased, the existing rivit and or weld lines would have to be removed and new ones added.
The Intermountain car is a GN designed car made from 1948 to 1959 to replace the wood sheathed cars essentially used for grain service. 6,489 of these cars were produced in a myriad of paint schemes. Some were used in passenger service as express boxcars. As they were all designed and made at the GN St. Cloud shops I doubt the design predates the first car off the line by much.
I have built and painted a number of these cars in the various paint schemes they wore!
And I still have a couple of more to do!
Rick Jesionowski
Rule 1: This is my railroad.
Rule 2: I make the rules.
Rule 3: Illuminating discussion of prototype history, equipment and operating practices is always welcome, but in the event of visitor-perceived anacronisms, detail descrepancies or operating errors, consult RULE 1!
The ones I got are Intermountain 1948 build date, Southern Pacific, T&NO rivited sides.
Let me check my car builders cyclopedia. I'll get back to you.
Edit: I have the 1946 Car Builders Cyclopedia and the 1947 Model Railroader Cyclopedia (5th Edition). I will take a look at those two documents and see what I find...the car builders is rather large....
So far: Most cars from the 1946 Edition are 10 panel. There is 1 Chicago Great Western 40'6" car that has 18 panel sides (each one is about the width of the ladder on the side of the car). Pg 128 Fig 2.136 They are also discussed the Pullman Standard Freight Equipment section. The 18 "panel" design was apparently a weight reduction (appear to be welded not riveted) design to help railroads lower dead weight in trains. No mention was made of a 12 panel design in the 1946 Cyclopedia that I could find.
Nothing in 1947 Model Railroader Cyclopedia of use to you.
Unfortunately I dont have access to previous editions of the Car Builder's Cyclopedia.
If I had to be a guessing man, the car you mention was likely designed around the same time it was built. Further research on the Pullman-Standard Co. may yield results. You may also try asking the question on Cody's Office, if you cant find the info via this forum.
The earliest 40' box 6' door 12 panel cars I can find were built in 1939 by Pressed Steel for D&RGW (series 68000-68399). They built 2000 more later.
There were also cars built for SP, T&NO, and Santa Fe starting 1947,EJ&E and GN in 1948,and SP&S (1949).
The reason there was more panels was because there were more side posts. And the reason there were more side posts was that the side sheets were thinner. And the side sheets were thinner because they buyers wanted lighter weight cars.......
I didn't turn up any prototypes built earlier. There may have been. But going from a 10 panel side to a 12 panel side is not exactly the height of innovation, so it's not unlikely there was never thought there was a need to do a practice version.
There WERE prototypes built of other lightweight designs.
Ed
7j43k The earliest 40' box 6' door 12 panel cars I can find were built in 1939 by Pressed Steel for D&RGW (series 68000-68399). They built 2000 more later. There were also cars built for SP, T&NO, and Santa Fe starting 1947,EJ&E and GN in 1948,and SP&S (1949). The reason there was more panels was because there were more side posts. And the reason there were more side posts was that the side sheets were thinner. And the side sheets were thinner because they buyers wanted lighter weight cars....... I didn't turn up any prototypes built earlier. There may have been. But going from a 10 panel side to a 12 panel side is not exactly the height of innovation, so it's not unlikely there was never thought there was a need to do a practice version. There WERE prototypes built of other lightweight designs. Ed
7j43k...going from a 10 panel side to a 12 panel side is not exactly the height of innovation...
I took it as a bit of a fuzzy question about antecedents. If one is speaking of basic design, your observation that counting panels doesn't tell you much except a number was why I decided to just go with design features rather than worry too much about counting rivet lines. Certainly, if one wants to match a model to a prototype exactly, counting panels counts. But other than that there really is little that's substantially different engineering-wise with the postwar cars than the basic AAR design that came along more than a decade earlier.
Technologically, RRs went from a vast array of different boxcar designs, mostly relying on some variant of a heavy underframe, to what aircraft designers refer to as monocoque construction -- the structure of the box provides much of the strength in itself, rather than relying on a strong frame below for that. That's what made an improved tare weight to carrying capacity possible. Sure, there were a bunch of variants on the basic AAR design, but they all shared this common thematic aspect in order to enjoy the benefits of weight reduction it offered over previous designs.
In this sense, the widespread postwar adoption of welding in place of rivets as fasteners was probably a bigger deal than panel count was -- and even that was a variation on the basic prewar AAR design concept.
Bacicly I like to do resurch on my model railroad era and try to buy things that realy existed or could have, just a different decision was made by a certain company that changed things. A good example are the S4 diesels as the main identifing thing outside is the trucks and those were available when the S1 was built so in my mind an S4 is as good as an S1 for my layout and gives me a wider range of Diesels in which to bargin hunt.
mlehman...your observation that counting panels doesn't tell you much except a number...
But that wasn't my observation. In this case, the number informs you that the car was designed to have a lighter tare weight. Now, for a modeler, that might be completely unimportant. But modelers have a tendency to be interested in the "insides", too. The "whys".
Thus, if yer wondering why Intermountain offers 12 panel boxes, you have an answer to the question: "Why in holy hockypuck would anyone add a panel????" Now ya know.
7j43khave a lighter tare weight. Now, for a modeler, that might be completely unimportant. But modelers have a tendency to be interested in the "insides", too.
Granted, but I read the question as revolutionary vs evolutionary change, another way of looking at this as a more general question than one specific to the car mentioned that prompted it. Used to be in the trucking biz and things like the number of panels tended to be incremental. YThings get bigger and the most efficient package needs touching up, although the basic design features tend to be maintained because that's what the technolical and maintenance base supports. It takes a sharp pencil to make such gains, so not disputing their importance either.
One could also argue that the source of such incremental evolutionary gains was that the basic design developed before the 12-panel was a breakthrough over those huge, deep underframes that in turn replaced truss rods, to go back another technological increment. It's that gain of maybe 50% over the previous design that makes the new technology quickly ubiquitous.
Just wanted to bring that up because our focus on prototype exactitude sometimes leaves us without an equally clear idea of what the bigger picture is that such changes are embedded in. Both provide useful insights into why things are.
The 12 panel boxcar wasn't an incremental evolutionary gain. There were many 10 panel cars built afterwards. And it was one of the least revolutionary designs.
I believe the idea was to save VERY roughly about 2000 pounds of tare weight by using a thinner side sheet. And I believe those thinner side sheets were made of stronger, more expensive steel. So they got a car that could carry 2000 pounds more load, but cost more. The idea sold to about 3 railroads. Leaving a LOT of other railroads uninterested in the design. And they kept buying the 10 panel cars. In a way, it might have been an evolutionary dead-end.
There were other designs of lighter weight cars, though. Again, the railroad world didn't fall all over themselves buying them. But they did sell. And over time, cars DID get lighter. A LONG time.
While we (that may really be I) like to think of the intelligent and innovative railroaders, they were in the minority. Most railroaders were not wild and crazy guys. Which DOES make some sense. How would it have been if artists and TV writers had designed railroads? Customers most want reliability in their transportation. I think.
Ed,
I think this is more a philosophical difference than anything. Just to leave readers with some food for thought, there's a very good NMRA clinic that covers things up through World War One and just after: http://sld-nmra.ca/freight_car/ref_material/freight_car_evolution.pdf
Then the leap to all steel construction was made in the late 1920s and into the 30s, spread over a lengthier period than would otherwise would have been the case due to the slowed pace of new rolling stock acquisition because of the Great Depression...
In "Freight Cars of the 40s and 50s" Jeff Wison continues, after discussing the 1932 AAR design:
"Boxcar evolution through the next two decades was largely a matter of increasing height and width, along with refining designs for individual car components."
https://books.google.com/books?id=WpiZCgAAQBAJ&pg=PA23&lpg=PA23&dq=boxcar+evolution&source=bl&ots=m7XQP1un2v&sig=XDNOKOMZLhwdbozLELE6KQiUA3k&hl=en&sa=X&ved=0ahUKEwit77DM44XPAhWDFT4KHRXhDzU4ChDoAQhFMAc#v=onepage&q=boxcar%20evolution&f=false
I believe he eventually gets around to discussing the 12 panel cars as one of these refinements, but my free viewing cut off before I could read that far. Perhaps someone has the book and can tell us what was said?
And there are other sources for this. I make no claim to it being an original argument, just that it's something to consider if one asks about the antecdents to the 12 panel cars.
mlehmanI believe he eventually gets around to discussing the 12 panel cars as one of these refinements, but my free viewing cut off before I could read that far. Perhaps someone has the book and can tell us what was said?
It does not appear to say anything at all. The 12 panel 40' car appears to be just an interesting footnote in history.
The 50ft car began to grow in popularity in the 50s, and other cars sold better (PS-1).