Apple Tape Backup 40SC question

[Scott Quinn]

 I've been talking with someone (the gentleman in Canada who has the A/UX 1.0 media (medium? it's just one tape...))
about getting his drive operational again (gummed roller). We've gotten as far as replacing the capstan with a similarly-
sized piece of tubing, and now he's having problems with the tape coming off the reels (no problems on another DC2000
(I think) style drive) I'm at a loss (can't see the setup, either). Any ideas? I've gone over the loose bands problem with him,
and it isn't that.