Try this one: Unwind the copper from an old heavy bass string, keeping the coils as close as possible as they unwind. Cut it to the proper length and insert into the stripped hole. Use two or three if needed. These act like a heli-coil insert used to repair stripped threads in metal. The screws will grab the copper and thread into the wood making a permanent repair. I've used these on grand leg screws that were stripped and they really hold! Mike Kurta
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