I dropped my box in a sewer, while being pushed over a "grate" in a wheelchair. The box was recovered 3 weeks later and it still worked, but was warped. I used the following technique to make the cover flush again. I wet the box by wrapping it in a damp washcloth for a couple of hours.... then I clamped it and left it for a week. what is not in this image is the small square piece of wood (a piece of a "yardstick") that I had clamped in also, to back up the "logo side" of the box. *note the string has nothing to do with this repair... I was borrowing a mini clothesline I use to dry herb.