A Riveting Solution

Most of Union Pacific's 40 and 50-foot boxcars constructed during the 1930s-50s shared many similarities with adopted AAR standards, but there were some important differences. One of the unique features that Union Pacific modelers have long had to overlook, was the alternate center rivet (ACR) pattern on UP's boxcars. In an effort to reduce the light weight of their new, all-steel boxcars, UP used lighter side sheets, but this required an additional interior post to maintain side strength, and subsequently, an additional row of rivets was present between the seams on the car side. Further, many of the 50-foot automobile cars had yet another style of rivet pattern, commonly referred to as twin alternating rivets, or TAR. This row of rivets was located much closer to the seam, and was found on the A-50-14/-15/-17/-18 series of 50-foot auto cars. Although unusual,  the 40-foot A-50-19s, and the 50-foot B-50-44s had both ACR and TAR.

This photograph of the side sheets of B-50-54 108875, rebuilt from a B-50-39 in 1965, clearly illustrates the ACR rivet pattern. Hooper, NE, August 2010.

Although models of the AAR standard cars have long existed from Red Caboose, Intermountain, and Branchline Trains, the distinctive ACR pattern was overlooked until Marklin / Trix released a model of the B-50-24/-27s. Resin kits from Sunshine and Speedwitch were also available, with ACR, but for UP modelers, the development of Archer Fine Transfers decal sheets with rivet head detail correctly spaced for ACR, finally made it possible to realistically model a fleet of UP boxcars with the distinctive rivet pattern characteristic of UP's postwar freight car fleet.

This Blog

This blog is an attempt to share some information and process of my HO scale modeling efforts, and with any luck it will not become just another distraction.

My primary modeling interest is Union Pacific branch lines during the 1960s, with Northern Pacific a distant second. Although the intellectual aspect of prototype research, of both equipments and regional operations is a very enjoyable exercise, for years, I have over analyzed my modeling preferences. Much of this struggle is rooted in the amazing diversity of landscape and railroad action in the Pacific Northwest; it is a land of arid wheat deserts, logging branches, and industrial centers. As a native of eastern Washington, my interests lie primarily with wheat branches, with a secondary focus on produce, canned food, and timber traffic. Eventually I may model the UP and NP between between Walla Walla, Washington and Athena, Oregon, or if afforded a larger space, between Walla Walla and Dayton. But that's for the future . . . .

Some of the Union Pacific projects I have researched and am slowly modeling, include the rebuilding of auto and box cars into maintenance of way cars, as well as chip racks for hauling wood chips; rebuilt general service gondolas for log hauling (with and without sides). While the number of accurate, or easily improved freight car kits has grown substantially in recent years, many of the most interesting prototypes still require considerable work in order to build up a model fleet of unique, era appropriate equipment. Currently on my workbench are several Branchline 40-foot AAR boxcars, that require some modification to accurately model Union Pacific and Northern Pacific 40-foot boxcars. More will follow on those subjects.

I am very interested in unique, but important, prototype freight cars, and would welcome posts from other researchers and modelers who discuss their work. Drop me a line if you are working on an interesting project, the more info and techniques that can be shared, the better.

Happy research and modeling,

Marc