A few weeks ago the Washington Post ran an interesting (to me) piece on the history of "Jim Crow". It found that the term originated much earlier than Reconstruction, and that the term was in fact first applied to railroad coaches, and at the very beginning of the railroad era.

There were a series of conflicts, court cases, and legislative initiatives in the 1840s related to Jim Crow segregation in Massachusetts.

https://www.washingtonpost.com/news/magazine/wp/2019/02/20/feature/the-forgotten-northern-pre-civil-war-origins-of-jim-crow/?utm_term=.2d66532e8582

If you want to read more about Jim Crow as it relates to rail transportation, check out Right to Ride by Dr. Blair Kelley. It covers both railroad and streetcar segregation.

https://www.amazon.com/Right-Ride-Streetcar-Boycotts-Citizenship/dp/080787101X

Here in Australia (and probably elsewhere) a jim crow is a rail bender. They had to stop calling it a jim crow when US servicemen came here during WW2 and worked on the railways, to not cause any offence.

Certainly used in the UK as well for something similar. My late Father said that the tool they used to use to straighten bent trolley poles on the local trolleybus fleet was known as a "Jim Crow" as well - and that was post WW2.
Presumably the manufacturers trade name for the product?

Don't forget this one!

https://patents.google.com/patent/US2157153

A jim crow is the usual name of an old fashioned rail bender in the UK as well. I wonder about the origins of the name, both elements have connotations of force. The tool itself consists of a large half moon clamp with two arms to grip the rail and a large square thread worm screw to drive the bending head against the rail, driven by something like a six foot 2" diameter bar driven by as many men as can get a hold.

Jim = jimmy or jemmy, a well known burglars tool for forcing doors, occasionally found in the phrase, " to jimmy a locked drawer". Also, a jimmy, or "firemans friend" (fireman = stoker) is a nefarious device, sometimes a clamp, which fits across a blastpipe to sharpen the blast and therefore the steaming of a sickly engine. They were reckoned to put a strain on the tubes so woe betide you if the shed foreman catches you. Professionally made ones were advertised as "removable in seconds". Guess why.

Crow - crow bar. To crow over, in railway speak, to force something, often rails, over to a new alignment with bars.

At any rate, a device to force something extremely tough to do something it is not inclined to do.

That was a common term for capstans in the US at one time, as in use they broke the rope fibers and got covered with curly little hairs.

I first heard that term used in reference to the turret of a steam locomotive.