HO-Scale Atlas

The "offset-side" hopper car had a few advantages over the earlier "rib-side" type. The crease in the upper sides led to more structural strength without using heavier materials, and there was a greater rated capacity with the side panels riveted to the outside of the ribbing, instead of being on the inside. The efficiency was a boon to the coal merchants! The concept proved successful, and was used to build ever-larger hoppers until after WW II, when "rivet pull-through" rendered it impractical for modern rotary dumping. Today, although they are seen less frequently, offset-side hoppers remain an important part of railroad history.