BOX CARS 101

- A brief history of box car development from 1937

These notes are an adaptation of the handout distributed at the 2005 Convention and include the captions and links to most all the images I used in the convention's PowerPoint presentation. They illustrate changes to box car designs between 1937 and the early 2000s. Many of the box cars listed below are available commercially in HO and N scale, so the images will help to put them into the timeline context. A small number of photos used in the presentation don't have on-line photos available, so they've been removed. I'm not a freight car expert, but I based the presentation on reference material gathered over the last 15 years or so.

Definition, Classifications and Major Builders

A box car is defined as a car with enclosed sides and having a roof. Doors are placed in the sides, or sides and end. They are used for general service and especially for lading that must be protected from the weather.

Box car development from 1937 can be split into two broad periods: The American Association of Railroads (AAR) designates the most common box car types by the following classifications: Major manufacturers of box cars are/were:
Industry rationalisation has resulted in three main builders of North American box cars in the 2000s indicated by * above. Some of the above manufacturers left the railcar building business in the early 1980s, or were merged or absorbed into Trinity Industries.

Overview

Steel box car production was common place by the 1920s and the most common early representative was the PRR X29 class with more than 29,000 built between 1924-1934 and many thousand more clones. PRR modellers will tell you correctly that the X29 is the most under represented model during the steam era (and probably into the transition era too) Picture .

Freight car historian and modeller Ted Culotta advises in his book "The American Railway Association Standard Box Car of 1932" that this design was the basis for the taller AAR 1937 standard design which is where we begin.

By the late 1930s the North American box car fleet still comprised many composite wood and steel box cars and many had reached the ends of their life. Steel box cars based on the 1937 AAR standard design were being produced in significant numbers to replace these worn out cars when the US entered World War 2.

The standardised period of box car construction from the late 1930s to early 1960s used modular construction and common components such as roof, ends, doors and side panels which could be used on both 40' and 50' box cars. These cars were double sheathed - the outer and inner walls were attached to a steel frame, initially with rivets and then welded. During this period there were a number of developments with changes to end, roof and doors being the most visible.

Ends and roofs manufactured by the Standard Railway Equipment Manufacturing (later Stanray) were commonly used, but the company required the use of both their roof and ends - they wouldn't sell them separately. This annoyed the car builders with ACF pressing their own from 1950-54 on 5,200 of their box cars to try and break the SREM monopoly. Pullman-Standard decided to use their own parts and developed their PS-1 box car - some variants of this design are included below. Riveted PS-1 construction was limited and this car pioneered mass welded construction in the early/mid 1950s.

General American popularised the 50' box car over the smaller 40' version and highlighted the benefits of load restraining devices. The increasing use of 50' box cars offered greater load capacity and larger door openings allowed carriage of larger items and use of forklifts to speed loading and unloading. Increasing door openings required greater reinforcement of the openings by using either a deeper side sill or reinforcement plates at the side of the door openings. Several examples of this are illustrated.

Pullman-Standard introduced exterior post (or X post) construction which did away with double sheathing. The structural ribs were welded to the side sheets making a lighter structure that increased capacity. This design was gradually adopted by other builders during the 1960s and became the standard thereafter, apart from specialised cars such as RBLs which still required a double sheathed design to allow filling the walls with insulation (as well as the ends, roof and underfloor areas).

During the 1960's interior lengths started to grow to 60' and up to 86' for auto parts box cars. Interior heights grew from 10' 6" (Plate B cars with unrestricted access across North America) to 11' 0" for Plate C cars (some minor limitations) and beyond that for high capacity cars. Load carrying capacity increased from the previous standard of 50 tons to 70 tons, while high capacity cars went to 100 tons. Cushion underframes or end of car cushioning became more common. Some designs and damage free loading equipment were tailored to specific commodities. Non terminating ends (end sheets did not wrap around corner posts) were introduced by Pullman-Standard and became the industry standard in the 1970s.

A shortage of general purpose XM box cars in the early 1970s started another period of significant box car construction. The Interstate Commerce Commission introduced increased per diem rates (daily usage payment fees) for new cars and the "free running" Incentive Per Diem (IPD) period really got underway in the mid 1970s. Trailer Train subsidiary Railbox commenced operations and eventually would own a fleet of almost 25,000 box cars that operated on this basis. The US recession of the early 1980s finished the IPD period and many of the recently built cars were left unemployed and looking for new owners. Box car production reduced significantly and for the 10 year period between 1984 and 1994, box car production effectively ceased. Rail car industry contraction and rationalisation took place during this period with a number of manufacturers leaving the market. Plate C cars became the defacto standard during the late 1970s (max height of 15' 6" empty)

Box car production recommenced in 1994 with larger Plate E and F ( max height of 15' 9" and 17' 0" respectively) high capacity cars being the norm. Many of the cars built in the 1960s have reached or are approaching the end of their 40 year interchange life limits. Trinity Industries, Gunderson (Greenbrier) and National Steel Car are the major box car builders in the early 21st century. Samples of cars built in the last few years complete the presentation. Plate F sized cars with up to 110 ton capacities are the new standard.

Every Picture Tells A Story

The following brief captions and image links illustrate how box cars have evolved since 1937 and demonstrate that not all box cars are the same. There were many other different designs which are not included. The various types of ends are illustrated, but roof types are not readily visible, although the descriptions indicate what the panels or pressings look like.

1937 AAR 40' box car - all steel construction with 4/5 (4 upper/5 lower pressings) dreadnaught end, Murphy rectangular panel roof, Youngstown 6' door, 10'0" internal height and 3700 cubic foot capacity. More than 100,000 built from 1937-1947. Picture

Modified 1937 AAR 40' box car - 5/5 dreadnaught end with 10'6" internal height and 4000 cubic foot capacity. Early cars had square corners like this one, later cars had rounded corners as illustrated in the following images. More than 45,000 built from 1939-1946. Picture

War emergency modified 1937 AAR 40' box car with 6 panel Superior door. Steel production was directed to the war effort, so wooden sides were used during the later years of World War 2. This is one of several designs. Picture

AAR 40' box car - 4/4 improved dreadnaught end and improved Youngstown door were introduced in 1945. More than 82,500 built from 1945-1957.Picture

AAR 40' box car - R(rib)/3/4 early improved dreadnaught end introduced in 1948 around the same time as the diagonal panel roof. More than 40,000 built from 1948-1957.Picture

ACF built 5,200 AAR 40' box cars with their own dartnaught end between 1950-1954. Picture

AAR 40' box car - R/3/4 late improved dreadnaught end introduced in 1955. More than 17,000 built from 1955-1961. Picture

AAR style 40' box car - this one with combination 7' plug and 8' sliding doors. Plug doors fit flush with the interior of the car. Overhanging eave roof was introduced in numbers from the mid 1950. Picture

To demonstrate the potential of 50' box cars, General American built 355 box cars like this one with Evans Products load restraining devices in 1950. Another batch of 250 followed in 1955. They popularised the 50' box car over the 40'. Picture

AAR 50' box car - this one with 8' single door. More than 30,000 built from 1950-1961. Same general components as AAR 40' box car. Picture

AAR 50' double door box car - this one with 15' door opening with 7' and 8' double sliding doors and 4970 cubic foot capacity. More than 45,000 built from 1950-1963. Picture

Pullman-Standard 40' PS-1 box car. More than 76,000 built from 1947-1967. 40' box car production effectively ceased in 1961 except for some specialised orders. Picture

Here's a specialised 1958 built 40' PS-1 fitted with roof hatches (AAR class LC) for loading kaolin clay powder for the paper and ceramic industries. LC box cars were mainly used in the South Eastern area of the USA. Picture

50' PS-1 box car - this 1955 one has a 15' door opening with 7' and 8' double sliding doors. More than 52,000 built from 1949-1972. The long production run saw the design modified to satisfy railroad and shipper requirements. Picture

The standard AAR 50' box car was superseded in the early 1960s. Manufacturers marketed their own designs with options for doors, loading equipment and cushioning to suit shipper requirements. This 50' PS-1 built in 1964 has 15' combination plug/sliding doors. Picture

Insulated box cars to protect temperature sensitive freight without refrigeration were developed in the early 1950s. The PS-1 design was modified and this 1966 built 50' PS-1 (AAR class RBL) features 20" hydraulic cushioning and 10'6" plug door. Full height ladders and running boards were outlawed on new cars in early 1966. Picture

This 1967 PS-1 50' box car (AAR class XL) has twin 8' plug doors, 20" sliding centre sill hydraulic cushioning and damage free loading equipment to protect its lading. Norfolk and Western had 1,000 cars in class B114. Picture

Pullman-Standard built a series of 50' box cars for the Southern Railway in 1960 which employed external post side construction (single sheathed) and non terminating ends for the first time. Picture

The simplicity of external post construction was embraced during the 1960s and by the mid 1970s had become the industry standard. Railroad car shops assembled this type of box car from 1961 with some of the first constructed by the Northern Pacific. Picture

Pullman-Standard perfected their non terminating end design in 1962 as railroads sought higher capacity box cars. This is an XL 70 ton car with 30" sliding centre sill hydraulic cushioning and 4954 cubic foot capacity. Picture

Another example of a railroad built exterior post box car is this 1964 built Pennsylvania X58B class 50' XL box car. Over 2,000 X58 class box cars were built between 1964-66. Picture

This is the Plate B clearance diagram for freight cars with unrestricted interchange access which was adopted in 1948 and the larger Plate C clearance diagram introduced in 1963. The larger Plates E and F were introduced in 1974. GNE_AAREquipmentDiagrams.htm

The automobile industry required specialised box cars to transport components with high capacity 60' and 86' cars being developed in the early 1960s. Greenville built this 60' XP auto parts car with 6000 cubic foot and 83 ton capacity in 1963. Some other types of auto parts box cars follow. Picture

This Thrall 86' XP hi-cube box car was built in 1964 with four Youngstown 10' plug doors per side. Car sizes increased with the introduction of the Plate C clearance diagram in 1963 - this car exceeded the dimensions and was restricted where it could travel when interchanged. Picture

This P-S 86' auto parts box car was built in 1967. Double door auto parts cars were much more common than quad door cars like the previous CNW car. 86' box cars had an internal height of 12'9" and 10000 cubic foot capacity. Picture

This is a 1969 built ACF 60' XL auto parts box car with 10' door and 6540 cubic foot capacity. It had a load limit of 83 tons. Auto parts box cars were pooled for each automobile manufacturer in the same manner as autoracks. Picture

Greenville built this 86' double door auto parts box car in the early 1970s. Picture

The final example of an auto parts box car is this 1978 Berwick Forge and Fabricating 60' car used in the Ford pool. Picture

The use of "waffle sides" which provided recesses for load restraining belt rails became more common in the late 1960s and into the 1970s. This 50' ACF XL waffle side box car was built in 1967 as one of 600 cars in SCL class X-5. Picture

P-S 40' appliance car. Only 122 were built for five railroads in 1967. These were close to the last 40' box cars built. 60' box cars were used for appliance service from the early 1970s. Picture

General American didn't build large numbers of box cars, but this 1968 built 50' XM box car with 20" end of car cushioning is typical of their later products. Note the relatively rare late 4/4 improved dreadnaught ends, rather than R/3/4. End of car cushioning tended to replace sliding sill and other cushioning types on cars built during and after the early-mid 1970s. Picture

ACF built this 50' XL box car in 1968. It was a 'Precision Design' series product, most of which are identified by the unique embossed panel design to the right of the door. Picture

National Steel Car of Canada built this 50' XM box car in 1969 for newsprint service. The internal height of many new box cars increased to 11' in the late 1960s. Picture

In the late 1960s and early 1970s, some old AAR 40' box cars were refurbished and/or stretched to increase life and/or capacity. This 60' RBL with 12' plug door shows its heritage after rebuilding by Chicago Freight Car Leasing in 1969. Picture

PCF delivered 7,000 RBL box cars to Southern Pacific and Cotton Belt from the late 1960s to mid 1970s. This car was one of 700 in the B-70-50 class delivered in 1970, but even the same class and order had differences such as doors - this one has Youngstown plug doors. Picture

This one has relatively rare Landis plug doors. Both cars featured a 14' door opening with 6' and 8' plug doors, Hydra Cushion underframes, DF-B loaders, 4836 cubic foot and 70 ton capacities Picture

US Railway Equipment produced a limited range of box car designs from 1969 to 1977. This 53' double door RBL box car was designed for their lease fleet, although some were purchased by railroads. This car was built in 1971 with an X panel roof. The X panel roof was introduced in the late 1960s. Early cars of this design used P-S built ends and roofs. Picture

Berwick Forge and Fabrication entered the box car manufacturing market in the late 1960s and built many thousands of box cars through to the early 1980s. This XM 50' box car with 10' plug doors was built in 1972. Picture

This US Railway Equipment design met with limited success - 1,077 were sold to the Penn Central and Western Pacific. This car was built in 1972 and is a member of PC class X72A. Picture

Several thousand Thrall 50'6" "All Door" (AAR class LU) box cars were built from the late 1960s to mid 1970s for the timber market. The four 12'6" plug doors gave an opening of 25' which simplified loading packaged timber. This car was built in 1972. Picture

Gunderson built this 60' XP box car for paper service in 1972. It featured double 8' plug doors, 20" end of car cushioning, 6200 cubic foot and 90 ton capacities. Picture

This is an example of how PS modified one of their designs in 1972 to produce a specialised box car for carrying 87 tons of steel can stock plate. Offset 12'6" doors to one end of the car made loading easier while four moveable bulkheads and end of car cushioning protected the load in transit. Picture

Gunderson/FMC built over 6,000 of these 5283 cubic foot double door box cars for SSW and parent SP in the early 1970s. This 1973 XM box car was similar to thousands of FMC double and single door box cars sold to railroads and leasing companies during the 1970s. Picture

National Steel Car built these 52'8" XM box cars with two offset 9' Youngstown plug doors for timber service in 1974. National Steel Car has dominated Canadian freight car construction for many decades. Picture

600 ACF 5090 cubic foot XM general service box cars were the start of the Railbox fleet in 1974-75. A further 2,800 identical XAF10 class cars were delivered to Railbox in 1975-76. The Railbox fleet eventually totalled almost 25,000 box cars. Picture

P-S built over 7,000 of these 5077 and 5277 cubic foot full waffle side box cars for the Southern Railway in the early to mid 1970s. This 1974 produced car was typical, with double door versions also produced. Remove the waffles on this car and you have a standard P-S 5077 cubic foot box car - see the Norfolk Southern/Southern car listed four below. Picture

Southern Iron and Equipment Company was a small freight car manufacturer who had good success with this 5100 cubic foot Plate B 50' design. This car was built in 1974. Evans built a modified design after buying SIECO. Picture

Rebuilding box cars was sometimes cheaper than buying or leasing new ones. UP rebuilt this 50' XM box car in 1974 with bifurcated ends.Picture

This 1959 built PS-1 was extensively rebuilt in 1975. A 14' plug door replaced the original 8'6" sliding door, the door opening was strengthened, the car was insulated and cushioning was added. Picture

All the major car builders got a slice of the Railbox action. 1,000 P-S 5077 cubic foot Plate B box cars were built in 1975 as class XPF10. This is the same design as the Southern waffle side car above. Railbox moved to larger Plate C box cars in the late 1970s. Picture

This 1975 built car is another of the 7,000 RBLs built by PCF for the SP and SSW. 1,650 of the cars came with 14' plug doors. PCF was the last major car builder to switch to non terminating ends, probably because they specialised in building RBLs which required double sheathed construction to sandwich the insulation. Picture

This 50' FMC XM box car built in 1976 was typical of the many thousands of incentive per diem Plate B and C box cars built in the second half of the 1970s. They were colourful, leased to smaller Class 2 railroads and operated as free runners like the Railbox pool. Like all booms there was a bust - the recession that began in 1980-81 burst the bubble. Picture

PCF built this 5598 cubic foot 60' RBL in 1977 for the Colorado & Southern. Air cushioned bulkheads and end of car cushioning protect its load of Coors beer. PCF used their own ribbed design roof on RBLs. Picture

BFF built this 7373 cubic foot 60' XL box car as part of a 50 car order for the Union Pacific as class B-100-5 in 1977. 1970s appliance box cars were commonly around this size. Picture

The P-S 5344 cubic foot box car was leased by many Class 2 railroads in the late 1970s and is readily distinguished by the rounded corner where the roof meets the side sheets. This car was built in 1978. Picture

Paccar built this 52' XM 5335 cubic foot Plate C box car with 12' door in 1980 just before the bottom fell out of the 50' incentive per diem box car market. This design was available with single or double doors in Plate B and C versions. Picture

National Steel Car built this 50' car for newsprint service in 1980. These cars were only sold to Canadian railways and Canadian National's US subsidiary Grand Trunk Western. Picture

This ACF 60' Plate F 6384 cubic foot box car was built in 1979-80. It has 20" end of car cushioning and load dividers to protect loads of up to 100 tons. Picture

Paper hauling is big business and this 50' Plate F Trinity Industries design competes with similar designs from Gunderson and National Steel Car. This one was built in 1994. Picture

Gunderson designed this 50' 6269 cubic foot car for paper service - it evolved from a similar late 1980s design. This car was one of the first built in 1994 and production still continues. This car is leased from GE Capital, hence the simple paint scheme. Picture

Gunderson built this 60' high cube XL auto parts box car in 2000. This design is also used for high volume freight and features double 8' plug doors, 7598 cubic foot and 100 ton capacities with 15" end of car cushioning. Picture

TTX received 4,600 TBOX cars from the major builders in 2003-05. National Steel Car built this 60' 9" Plate F 107 ton capacity high cube box car in March 2003 for TTX pool service. Picture

TTX received 2,200 of these FBOX 50' Plate F high cube box cars from the major box car manufacturers in 2003-04 for pool service. This is an NSC built 6264 cubic foot car with 10' wide door, 8" end of car cushioning and 102 ton load capacity. Picture

References

e-mail Discussion Groups:
- Modern Freight Cars list
- Steam Era Freight Cars
- Freightcars list

Useful Internet sites for box cars and other prototype images include:
www.rr-fallenflags.org
www.railarc.org
www.trainweb.org/nwrp
www.krunk.org
www.railcarphotos.com
www.rrpicturearchives.net

John Gillies

gillies@webone.com.au