So, I have this lathe. Classic South Bend 10K (heavy 10) toolroom lathe. I got it used many years ago, and it has served me very well.
Used tools generally have some sort of idiosyncracies.
This is the back guide of the lathe carriage. Note that it is slightly tapered. Note the paint sort of worn off on the right side at the bottom. This is because for some reason, this guide would only fit behind the tailstock for about 2 inches of its length, and then would bind against the tailstock. About 2.5 inches of carriage motion which would normallly be available was not usable. While this has never actually stopped me from being able to do a job, it has on occasion made certain jobs very annoying. Unclear as to why the heck it was like this; my best guess is that somewhere in the distant past, someone at the machine shop I got this unit from had removed the original tailstock for some reason, and months later someone else stuck on one from a different model year, which was really *close* to completely compatible but not quite, and the annoyance was never quite enough for *them* to deal with it either.
Anyhow, finally...
Yep. Thats the lathe tailstock in the Bridgeport vise. 2 minutes of work, and problem finally dealt with. Carriage now has complete range of motion, as it should. Yay!