1842 Millholland 6 Wheel Boxcar

A model of the six wheel boxcar designed by James Millholland in 1842 for use on the Baltimore & Susquehanna Railroad. These tiny boxcars rode on six wheels and used planks of wood as "springs". The model was scaled from the 1840s patent drawing for the wooden springs, the dimensions in the drawing were checked against measurements of actual freight cars used on the B&S in the 1840s and found to match within an inch or two in overall dimensions.
This model will take 33" or 36" wheels on standard 26mm axles (33" being correct scale, but spoke wheels are easier to obtain in the 36" size).

The couplers on this car are designed to be coupled to each other with a simple piece of bent wire. Wire bent in a U shape can be inserted into the couplers from below, and the tops of the wire once protruding through the tops of the couples bent over to mimic pins of link and pin couplings. I recommend roll-tru wheels in the 33" size, or Gibson spoked wheels in the 36" size (10.5mm), both easily obtainable from online sources.