A jim crow or rail bender is a tool for bending rails, consisting of a U-shaped or V-shaped armature with a hefty screw rod in its axis. Deluxe models are outfitted with rollers for continuous bending.
Practice Railway rails are quite flexible and bend easily to radii of 400 m (440 yd) or more. The jim crow is needed to bend rails to tighter radii, especially near the ends.
References
External links http://www.catskillarchive.com/rrextra/tkwk03.Html (with illustration) Photograph Railway Object Name Thesaurus