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   Though longer boxcars were developed early in the last century, the forty-foot car remained the mainstay of the railroad industry well into the fifties.  Starting with the ARA 1924 designs of the twenties, boxcars gradually grew in height and capacity, culminating in cars with an inside height of 10’6”, such as Pullman Standard’s PS-1 boxcar.  As boxcars grew in size and complexity, the plain “XM” boxcars were replaced by more specialized equipment as listed below:


XAP (Later XP)- A boxcar equipped with permanent racks for stowing automobile parts.

XAR (Later XR)- A boxcar with side doors at least ten feet wide, and equpipped with permanent automobile stowing equipment.  It may be with or without end doors, and is often marked “Automobile”.

XF- A boxcar with an interior coating (usually epoxy) to prevent contamination of processed foods. 

XL (formerly XL)-  A boxcar equipped with side rails or other “Loader” devices designed to secure lading.

XM- A boxcar used for general service

XP (formerly XMP)- A boxcar specially equipped for a specific commodity, and not suitable for general service.  The commodity is usually noted in the Equipment Register

XI- A boxcar that is wholly or partially insulated, but not equipped with ventilation or refrigeration equipment.   This classification was eventually discontinued, and an insulated car would be indicated by adding an “I” to other classes: XMI, XLI etc.

XT-  A boxcar enclosing one or more tanks; it may or may not have doors.


  Construction of forty-foot boxcars ended in the late sixties.  During the seventies, as cash-starved railroads invested in specialized types of freight cars, a boxcar shortage ensued.  This was relieved in the late seventies by Railbox and a boom in colorful IPD (Incentive per-diem) short line boxcars.  By 1981, the IPD boom had turned to a bust and the nation was in an economic recession.  These events spelled the end for forty-foot boxcars; though a very few hung on for hauling contaminating commodities such as hides, fish meal or tankage.  In Canada, forty foot boxcars hung on for another decade or so longer, as they were needed to haul grain on branch lines with rail that was too light for large covered hoppers.  

B4 Red Caboose X29.jpg




  The ARA 1924 boxcar became the standard steel boxcar of the roaring twenties. Based on a Pennsylvania Railroad design, it is distinguished by a low profile (inside height of 8’7”), Creco three-panel doors and flat plate ends.  The largest fleet belonged to the Pennsy, whose fleet of over 30,000 cars was designated as X29’s.   This single class of cars exceeded the entire roster of many railroads, and these cars could be seen all over the country.  If you model the forties or fifties, a “circle keystone” X29 (Which Micro-Trains still hasn’t made!) should be in your collection.  As you can see from the chart below, these cars were popular with northeastern roads, presumably due to tight clearances.


   Red Caboose, Micro-Trains and Atlas have offered models of this car. The Red Caboose models are available with either flat ends or Dreadnaught ends, and either Creco or Youngstown doors.  Micro-Trains offers four variations depending on roof type (flat panel or Murphy), door (Creco or Youngstown) and handbrake.  Atlas offered a model year ago with Dreadnaught ends and Youngstown doors.  Except for the Linde Air Products car, none of the road names were appropriate for the model.


   With all these variations, I will assume the manufacturers have done their homework, and will outline only the exceptions below:

CANADIAN PACIFIC- These cars had radial roofs, Dreadnaught ends and five-foot Youngstown doors.

CHESAPEAKE & OHIO and PERE MARQUETTE- These cars had Dreadnaught ends and Youngstown doors.

ERIE- These cars were of similar dimensions, but had different roofs and ends.

HIGH POINT, THOMASVILLE & DENTON- I’m not sure if Red Caboose ever actually released this road name, but they were similar but higher cars.  After selling some to West India Fruit in 1949, the few remaining cars were not used in interchange.

LINDE AIR PRODUCTS- As class XT box-tank cars, the Equipment Registers didn’t provide much information.  Photos show they look similar to the model, but were higher cars with an inside height of 9’6”.

PENNSYLVANIA- Both Micro-Trains and Red Caboose offered an X29 in the “Railway Express” scheme.  These cars were equipped for passenger service, and some lasted right up to the eve of Amtrak.  They are listed in a separate chart below with figures from Passenger Equipment Registers.  The “Buy war bonds” logo was applied to a few cars during World War II.  In 1950, some cars were painted in the “Merchandise” scheme for Pennsy’s LCL (Less-than-Carload) service; these would have remained primarily on-line, at least until the service was discontinued.

SEABOARD AIR LINE- Micro-Trains 120230 represents a series of ARA composite cars that had been rebuilt with steel sides; these cars had flat panel ends and Youngstown doors.  Micro-Trains 120250 is numbered for the slightly larger 1932 ARA boxcar, which is discussed separately below.

WEST INDIA FRUIT-  Though similar to the model, these were higher cars with an inside height of ten feet. 

Chart ARA 1924.jpg
B4 Broadway NYC boxcar.jpg




   It’s not surprising that the New York Central developed a different boxcar design than arch-rival Pennsylvania.  Though it’s a bit of a surprise that a model would come from a company named Broadway Limited!  The Central’s boxcars shared the same inside height (8’7”) as their Pennsy counterparts, but differed in details.  The New York Central cars featured four-panels on either side of the door, corrugated ends, and grab irons instead of end ladders.  The final lots delivered in 1927 featured Dreadnaught ends, and Broadway Limited offers both versions.  Though fine models, they are for post-war modelers only as they all feature the 1935 “System” logo.  Hopefully BLI is reading this and will eventually offer the pre-war schemes as well.  In addition, the Delaware, Lackawanna & Western owned similar cars, and the Northampton & Bath got second-hand cars from the NYC.


   The chart below lists cars both type ends separately; this wasn’t possible in later years as the series were combined in the Equipment Registers.  A “CE” in the bottom chart indicates that the total for cars with Dreadnaught ends is included in the top chart.

Chart NYC boxcars.jpg
B4 Atlas USRA rebuild.jpg




   The majority of USRA composite boxcars were later rebuilt with steel sheathing.   These conversions began in the thirties and continued into the fifties.  The primary characteristic of a rebuilt car is the recessed side sill along the bottom of the car.  Adding steel sheathing to the outside of the frame made the car several inches wider.  Other spotting features are the Murphy corrugated ends and grab irons instead of end ladders.


   Each railroad rebuilt their cars differently; often increasing the width or height, sometimes replacing the roof, ends or sides.  Some roads, particularly in the later years, essentially built an entire new car atop the USRA underframes, creating cars that differ from the model.


   Because the cars of each road are unique, it is difficult to produce a read-to-run model for each.  The Atlas model offers two types of ends, doors and underframes for a total of eight possible variations.  Though photos of rebuilt cars seem to be hard to come by, a general rule of thumb is that cars retaining the original inside height of nine feet bear the closest resemblance to the model.


  The “IH” column in the chart below lists the inside height of the prototype car.   The “NOTES” column indicates differences in the prototype as follows:

An asterisk indicates a car that is close to the model, D=dreadnaught ends, L= end ladders instead of grab irons, M=modified ends, R=different roof, 7= seven-foot doors, #= Merchandise car designated for on line use.

Chart USRA rebuilt boxcar.jpg
B4 1932 ARA.jpg




   The ARA 1932 boxcar was the next step in the evolution of the boxcar.  It was essentially a taller version of the 1924 car, raising the inside height from 8’6” to 9’4”.  Like its predecessor, the ARA 1932 car featured flat plate ends.  Because of the depression, it was not built in great numbers.


   The Atlas model is available with two different bodies, three different ends and three different roofs, so every road name should be an accurate representation.  The Roberval & Saquenay car is the only possible exception; it is listed as a “steel frame” car with an inside height of ten feet.   

chart ARA 1932 boxcars.jpg
B4 PRR roundroof.jpg




   The standard inside height for boxcars was nine feet, four inches in the early thirties. The Pennsylvania Railroad felt a need for higher capacity boxcars, particularly for automobile service.  They developed the X31 boxcar with an interior height of ten feet and rounded edges at the roof to reduce clearance problems.   These cars were constructed as both double-door cars (X31) and single-door cars (X31a), and were used by other railroads under Pennsy control. 


   Though no ready-to-run models are available in N-scale, cast resin kits of both versions are available from Fine N-scale.  The chart below lists the roads that originally owned X31 boxcars, as well as the short lines that picked them up second hand in later years.

Chart PRR X31 boxcars.jpg
B4 B&O wagontop.jpg




   During the depression, the Baltimore & Ohio tried a new method for constructing freight cars.  Their design consisted of constructing cars from “U” shaped panels that comprised the both the roof and sides.  This method, which reduced both construction cost and tare weight, produced a rounded profile that earned them the nickname “wagontop”.  Their official Baltimore & Ohio designation was class M-53.  Though originally equipped with flat panel doors, some received Youngstown doors in later years.


   Fox Valley Models offers a model of the M-53 in a variety of paint schemes and both types of doors.  The most common B&O schemes are listed in the chart below; including schemes used briefly in passenger service.  Fox Valley also produced several other schemes which I believe were one-of-a-kind or error schemes, and are not included in the chart below.  Fine N-scale also offers resin kits of the M-53 with both types of doors.

Chart B&O wagontop.jpg
B4 Hi-cube SD.jpg




   The adoption of tri-level auto rack flatcars prompted the railroad industry to begin raising height clearances on their main lines.  This led to the development of hi-cube boxcars, which were primarily used by the auto industry.  In the late sixties, forty-foot high-cube boxcars were developed for shipping household appliances.  While these cars had the same cubic capacity as a standard fifty-foot boxcar, they allowed for more efficient use of the space by providing more height for stacking appliances.  They were also compatible with older warehouses whose doors were spaced for forty-foot boxcars.


    Micro-Trains introduced an N-scale model of a Pullman Standard forty-foot hi-cube boxcar with 10’6” sliding doors in 2005.  The prototypes were sold to at least six railroads with two more acquiring them through merger.  In addition, five railroads rostered similar cars from other builders.  Total numbers were small, and paint schemes varied depending on the loading devices installed in the cars.  The chart below is a comprehensive listing of forty-foot hi-cube boxcars.  An asterisk in the ROAD column indicates car series that differ from the model as noted below.


ATCHISON, TOPEKA & SANTA FE- Santa Fe’s boxcars were built in two lots by Transco and featured nine-foot Youngstown doors with straight side sills.  The second lot carried a black DF logo in the upper right corner.


CHICAGO & NORTH WESTERN- CNW’s cars were built by Maxon and featured six-panel Superior doors.


ST. LOUIS SOUTHWESTERN and SOUTHERN PACIFIC- Espee and Cotton Belt rebuilt standard boxcars into hi-cubes in 1964-1965.  These rebuilds were about six inches lower than other hi-cubes, had Youngstown doors and a horizontal riveted seam where the roof was raised.  


UNION PACIFIC- Union Pacific’s first appliance cars were built from standard double-door cars by raising the roof but not the doors.  Since these cars bore so little resemblance to any N-scale model, they are not included in the chart below.  Micro-Trains 10100040 represents three groups of cars constructed in UP’s Omaha shops; they were equipped with Youngstown doors bracketed by triangular gussets.




   Bachmann introduced an N-scale model of a Union Pacific forty-foot BF-50-4 hi-cube boxcar with ten-foot plug doors in 1972.  The original release (catalog # 5125) was a nice release for its time, but looks a bit dated today. The second “Silver Series” release (catalog #71251) has much sharper printing, while the third release (catalog # 18254) features a consolidated stencil, an ACI placard and a wheel inspection dot which dates it to 1978 or later.  Only the Union Pacific owned plug-door cars, so most of the other road names offered by Bachmann are stand-ins for sliding door cars.



   Bachmann introduced an N-scale model of Southern Pacific’s B-70-36 boxcars in 1972.  The prototype was built by Pacific Car and Foundry in 1966, and featured six-panel ribbed sides with 10’6” Youngstown doors.  These cars were unique to the Southern Pacific and St. Louis Southwestern.   The original release included six roadnames, four of which never owned forty-foot hi-cubes of any kind (B&O, GN, PC, SCL).  Recent releases include three roadnames which are stand-ins for smoothside cars, but sadly, did not include Southern Pacific or Cotton Belt.

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