N Scale Southern Pacific B-50-15 3d printed resin kit

Southern Pacific B-50-15 Boxcar Kit – N Scale

By Folsom Locomotive Works and Out of the Box Models

Bring a cornerstone of Southern Pacific’s transition-era freight roster to your layout with this highly detailed SP boxcar kit, representing the B-50-15 class— one of SP’s most numerous and widely traveled 40-foot boxcars, seen system-wide from the 1920s through the diesel era.

The original digital model for these cars was developed by Out of the Box Models, whose work laid the foundation for this project. Folsom Locomotive Works subsequently undertook a comprehensive redesign of the model, refining proportions, surface detail, and class-specific features to more closely match Southern Pacific prototypes. Following this work, FLW and Out of the Box Models reached an agreement allowing both manufacturers to offer the same underlying model, each through their respective sales channels.

Customers should note that this is the same model offered on the Out of the Box Models website (https://outoftheboxmodels.com/). Out of the Box Models offers the STL file for customers who wish to print the model themselves, while Folsom Locomotive Works supplies physically printed kits only and does not distribute STL files or other digital IP.

This kit is offered in two variants: wood side & steel side

B-50-15 with corrugated steel ends and simplified Viking Roof

Each class available with as-delivered wood sides or later steel-sheathed rebuilds
(Not all cars were rebuilt; many retained their original wood siding until retirement.)

The model accurately captures the structural differences between these variants, enabling era- and photo-specific modeling rather than a generic stand-in.

Both Out of the Box Models and Folsom Locomotive Works have produced high-quality, prototype-specific decal sets for these cars. Each manufacturer’s decals feature entirely different road numbers, allowing multiple cars to be rostered without duplication.

Designed for experienced modelers and kitbashers, this kit is ideal for those who enjoy hands-on assembly, detailing, and finishing—and for anyone seeking an accurate representation of one of Southern Pacific’s most ubiquitous boxcar classes in N scale.

Kit includes:

Detailed 3D-printed resin car body

Notes:

Decals not included (Sold Separately)

T-section Bettendorf trucks sold separately 

Paint not included

Resin parts are more delicate than injection-molded plastic — handle with care and avoid direct sunlight

© 2025 Folsom Locomotive Works.
Model geometry and design are original works.
Unauthorized reproduction, redistribution, or resale prohibited.