When setting stones in thin rings that may bend, take a ball of shellac that will fit easily into the finger hole of the ring. Warm the ball of shellac and place it in the finger hole. Then place the ring with the ball, in a ring clamp and tighten the clamp. The warm shellac will spread through the ring supporting the thin top for setting. To remove, warm the shellac and push out. When cool place the ring in alcohol to remove the remaining shellac.