[Red to black]

Superglue is not very good for sticking the backtension band back on with, it tends to soak into the felt going hard and very rough causing excessive backtension, a better glue is something thicker and more flexible like a contact adhesive (Evostik impact in the UK).

This ^^^ adhesive worked ok on the earlier type bands that were copper coloured metal but could not be used on the later clear plastic type (they melt with that type of glue).

Back in the day we only glued them back on if we did not have the required band in stock, and even then it was only to check out the rest of the machine for any further problems before quoting the final repair bill, the band was ultimately replaced for new in any event should the estimate be accepted.

We often required the full maintenance kit for the (Panasonic) Machine in question to be fitted anyway for a reliable paid for guaranteed repair.

The above still stands though RE: type of glue used even if the repair is for yourself.