Does anyone rewind partially exposed rolls in order to switch film?

I’ve done a it a couple times and it seems as though it works fine. I figure I’m losing a frame or two or I risk double exposing part/all of a frame so I just as one or two extra onto the exposure count.
I don’t have anything to retrieve the film if it goes all the way in the canister so I just try and listen and feel for it popping off the spool. So far so good but I’m sure I’ll ruin a roll at some point

I learned how to switch film a long time ago. I don't recall actually doing it other than as an exercise. If I thought I might need a different film, I carried a second body. Film switching does work, so if you need a different film and you don't have a second body, it is something good to know.

wattda said:

I used to do it when had 1 camera. My success rate was about %50 ,scratches loss of exposures, etc . Now that a roll of film is more expensive than some of the camera bodies I have, it doesn't make a lot of sense. Unless your camera breaks and you want to save the remainder of the roll.

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Incidentally, any idea why it would cause scratching? I wouldn’t think it a couple extra passes into and out of the canister would cause that but maybe I’m missing something