The earliest reference to conversion of XL box cars to maintenance of way and crew cars (or camp cars as they were called by the Pennsylvania Railroad) is 1937. Blueprints were issued for standard sets of cars. One set entitled "four car unit for living quarters" included a riding car, two sleeping cars and a kitchen/dining car. Another entitled "four car unit wreck train" included a tool car, cable car, riding/locker car, and commissary car. A third showed wire train cars: a riding car with cupola and pantograph and a tool/material car. These were far from the only variations as photos reveal many others. The details, especially smoke jacks and vents were added from available supplies, resulting in standard cars on which almost nothing was standard. The Westerfield models are based on the blueprints in most cases as the plans reveal the position of internal details making the location of ventilators more precise.
The Pennsy's fleet of H25 class hoppers were built between July 1919 and July 1923. In addition to the 3,000 built for the PRR, the Pennsy 2,287 of the same cars from private operators, including Emmons Coal Company, Bethlehem Steel Company, Pickens-Mather and Co., and Youngstown Sheet & Tube Co., bringing the total to 5,287. Other than 500 purchased from Emmons, all others were built by Cambria Steel in Johnstown, Pa.
The H25 differed subtly in appearance from the H21A, and was done so because of lessons learned from the H21, H22 and H24 class hopper cars. The cars were initially delivered with a "drop-door" arrangement, but by August 1928 conversions began to the more modern "saw tooth" arrangement. There were many more differences, particularly on the ends, which are discussed in John Teichmoeller's book, Pennsylvania Railroad Steel Open Top Hopper Cars.
The X26 series were 40' World War I composite box cars based on an AAR design.
Due to a variety of door and ladder combinations within subclasses, photographs should be referenced for accurate road numbers. Photos of models cannot be trusted for legitimate road numbers, but photos of completed models are included for illustration purposes.
In 1945, the Pennsylvania created a lightweight 50' boxcar unique in appearance, all welded and with slightly excess height, the X41 series. The use of sheet steel only .07" thick welded to vertical posts every 2' yeilded a car side with a mass of wrinkles. The interior height of 10'8" added to the massive appearance. The X41's were the PRR's last major home design.
The X43 series were 40' post-war steel box cars based on an AAR design.
With more than 42,000 cars built for the American railroads and 38,000 for the Canadian roads, the postwar AAR 40' boxcar was one of the most widely used freight cars. Many of these cars saw service into the 1980s. Like their 50' design, the AAR 40' box car was modular in concept and the primary aspects of the design standard were dimensions that must be conformed to. The side panels, ends, and roofs were nothing more than component parts that could be used interchangeably.
The 50 ton postwar AAR 40 foot boc car was on illustration of a standard car in a continuing series of AAR standard designs that began in 1932. THe original 1932 AAR had a standard inside height of 9'11" and the 1937 AAR standard box car had a 10'0" inside height. In October, 1947, the Committee on Car Construction revised the inside height from 10'0" to 10'6" because there had been little demand for the 10'0" height car. Standard features of the postwar AAR 40' box car were as follows:
The G35 was essentially a revised version of the G31. It shared car-body dimensions and ends (52'6" internal length). It differed in that there was a dip in the cross-bearers to allow passage of a continuous length stringer for more durability. Also, the top cord was constructed of two chanels welded flange to flange to form a box vs. the "Z"-angle found on the G31.