Maybe the issue in question then isn't the tape,
but that the drive is
out of alignment. When a floppy is out of alignment, it won't matter
if you put brand new disks in them, it won't work properly.
Eh?
If a floppy drive is out of alignment (this generally means 'radial
alignment'), it will read its own disks. You can take a bulk-erased disk,
format it, rite to it, and read it. What you can't do is use that disk in
a correctly-aligned drive, or use disks from a correctly aligned drive in
an incorrecetly aligned one.
In fact, if you are repairing a floppy drive, you get it working on a
blank disk first. That verifies that the drive is capable of working
correctly. Only then do you put an alignment disk in and do the
adjustments. If you put the alignment disk in from the start, there's a
chance you'll ruin the alignment disk (maybe the write circuit is
permanently enabled due to an electronic fault).
-tony