No, you're right - a sander won't help with the stripping. Foolish to even try. But, it's going to get to the point where paint removal chemicals aren't helping much, and you'll need to clear the wood. You don't want to sand by hand because you risk putting waves in the flat surfaces. Then, when you put the new finish on, it'll look like a dingbat did it. You can use block sanders, and they not only work well but are absolutely necessary when you start applying the actual finish, but when you're tearing the thing down you don't want to work so hard.