The BX-11 was the first single sheathed box car on the Santa Fe. A variation of the ARA 1924 design, it had increased height. The ends and radial roof of the previous design (BX- 8/9/10, ARA double sheathed standard design with dreadnaught ends) were used on these box cars. Doors were Youngstown 5-7-6 rib design, and this class was equipped with Ajax power handbrakes. A unique feature of these cars were the lower cor- ner braces; rods fitted into screw fittings at floor and end, they formed what was for all purposes a truss rod.

Two thousand of the BX-11 were ordered from four builders in 1929 (see chart at end of instructions). Following the success of this design, 3,500 cars were ordered in 1930, classed as BX-12. The differences between the BX-11 and BX- 12 were slightly different Dahman two-level trucks (BX-11 used AT&SF 1151 whereas BX-12 used AT&SF 1228) and grab bar placement (BX-11 had straight grabs above attaching bolts where the BX-12 had drop grabs placed below).

The final order of 1,000 cars, classified BX-13, was placed in 1931. Differences included a peaked solid steel rivited de- sign roof, 12 panel design (radial roof design had 12 panels plus 2 halves), and doors with a 5-6-6 rib design.

In the 1940s, ATSF began replacing the roofs on the BX-11/12 to ones similar to the BX-13s, but at the same time raised the interior height to 10’0”.

Includes two of the artwork shown, and will letter two cars of different classes in one of each scheme (early or late). Intended models Westerfield Kits 4600, 4700 or 4800.