"Using dry ice to repair dents in car bodies caused by hail is an old trick. The idea is to freeze the dented area and then to reheat it suddenly. The change in temperature causes the metal to contract and then expand in such a way that very often any dents "pop" right out as if they never existed in the first place. Occasionally you may wish to lightly rub the area with 0000-grit steel wool if the paint has cracked, but other than that dry ice and heat can be a "miracle cure" for hail stone dings.
Read more: How to Use Dry Ice to Repair Hail Damage"
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