I assume you are familiar with StewMac's sanding stick for working frets?
This thing…
The sanding strips are troublesome when they get old. The glue fails on the fiberglass reinforcement strip. And then the barely used sanding strip gets tossed. I had enough, and like a lot of frustrated luthiers - I saved the strips in a baggie for reuse sometime in the future.
Now I am supergluing these strips back together so I can use up ALL the abrasive. Just takes a dot of glue, and a quick pinch until it cures. If the reinforcement tape fell off, you can still superglue the strip together by overlapping it. Works fine. Just don't locate the glued joint near the point of the sanding tool, or it will come apart.
Thusly...
https://imgur.com/T0iCGKb
https://imgur.com/ZQHThw4
And now back to work....