Fixing/Replacing Conductor Ribbon Cable

I think this is the type of membrane keyboard where the metal is extremely thin. It's often not copper foil as you might expect, rather I think it's printed silver paste. Basically, it has no structural integrity of its own, relying on the plastic for that. If you rub away the surface of the metal, you quickly discover that the surface is all there is to it.

If your ribbon cable consists of two layers of plastic, with the tacks printed onto the inside surface of one, then you may have some success. Try to peel the two layers apart, and cut the non-track layer a few mm shorter.

Alternatively, you might try repairing the broken tracks with some wire glue.

Follow the instructions on Repair the Keyboard Membrane.:

There was an extended discussion on this in the home shop machinists forum a while back.

Answers ranged from "don't waste your time, replace the cable" to a half dozen ways to actually attempt to do so. My own take is that any repair is not going to be as reliable as outright replacement, but since/if you have nothing to lose, why not try?