Re: SWING-MOTION TRUCKS

I never figured out swing motion trucks until I found this site by the
Society for the Preservation of Carter Railroad Resources. This truck does not have an equalizer, and has coil springs instead of leaf springs, but it's a great illustration of the swing motion.

You might also have a look at the 1895 Car Builder's Cyclopedia of American Practice available online from Google (search for the book title).

In particular, figures 4751 (caboose trucks with no equalizer, but a clear drawing of the bolster and hangers), figure 4806-8 for a passenger truck, and figure 4942 has a good cross section showing the hangers (as suspended from the bottom of the cross members like the Hartford model, instead of hooked over the top of the cross members like the EBT and Carter trucks).

Also, the spring hangers are not vertical but slightly canted, which not only raises the bolster when the car shifts sideways (in a curve), but also leans the car into the curve.

So, car bears on truck bolster, truck bolster bears on leaf springs, leaf springs on spring plank, spring plank on cross members via the hangers, cross members on sideframes, side frames on coil springs, coil springs on equalizer, equalizer on journal boxes, journal boxes on bearings, bearings on wheelsets, and (whew!) wheelsets on rail. Sounds like a song in there somewhere.

William Adams