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In 1958 and 59 the Alaska Railroad took delivery of 100 flat cars from Thrall Car MFG as described below. These cars in the Alaska Paint job were subject of an advertisement from Thrall. The side sills were unique in appearance as they had a gusset plate added over most of the car side from bolster to bolster.

Model starts with Proto 2000 Walthers standard 50 ton Flat. The number of stake pockets (15) is close as the prototype had 14 and length of deck at 53'2" is correct. The side sill needs some addition to match the appearance of the prototype. The existing side sill of the model will represent the gusset of the prototype. We will add a strip of .040X.060 styrene to the bottom edge of the sill offset to the inside to create the recessed portion of the side sill. This will run between the 2nd stake pocket in from each end and be offset approximately 1.5 to 2 scale inches in from the side of the original sill. See the detail photos below.

Notice that the side sill bottom offset is not present below the last two stake pockets but is rather flush with the side sill. These are all welded cars so the rivets on the side sill should be removed except for the stake pockets. With the addition of four strait hand grabs, Aline stirrup steps, cut levers and the brake wheel the car is ready for paint. I used mineral red and a mix of decals from Randy Thompson to finish the car along with miscellaneous yellow car data sets. Kadee 158 couplers and Barber S2 trucks finished the job.

These 50 ton cars had a long service life on the line. In 1984 there were 88 cars in service and 27 were equipped with metal stakes and chain binders for container service. By 2003 there were 84 in service and that number dropped to 61 by 2006. As of 2008 there were only eight of the 12800 series cars left and all were in MOW service.